Abstract
Global deterioration of water, soil, and atmosphere by the release of toxic chemicals from the ongoing anthropogenic activities is becoming a serious problem throughout the world. This poses numerous issues relevant to ecosystem and human health that intensify the application challenges of conventional treatment technologies. Therefore, this review sheds the light on the recent progresses in nanotechnology and its vital role to encompass the imperative demand to monitor and treat the emerging hazardous wastes with lower cost, less energy, as well as higher efficiency. Essentially, the key aspects of this account are to briefly outline the advantages of nanotechnology over conventional treatment technologies and to relevantly highlight the treatment applications of some nanomaterials (e.g., carbon-based nanoparticles, antibacterial nanoparticles, and metal oxide nanoparticles) in the following environments: (1) air (treatment of greenhouse gases, volatile organic compounds, and bioaerosols via adsorption, photocatalytic degradation, thermal decomposition, and air filtration processes), (2) soil (application of nanomaterials as amendment agents for phytoremediation processes and utilization of stabilizers to enhance their performance), and (3) water (removal of organic pollutants, heavy metals, pathogens through adsorption, membrane processes, photocatalysis, and disinfection processes).
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
Introduction
The ongoing propagation of industrialization and urbanization processes involving transportation, manufacturing, construction, petroleum refining, mining, etc., deplete the natural resources as well as produce large amounts of hazardous wastes which cause air, water, and soil pollution and consequently threaten human public health and the environmental security. The generated wastes are released to the environment in different forms, for example atmospheric pollutants include toxic gases (nitrogen oxides, sulfur oxides, carbon oxides, ozone, etc.), suspended airborne particles, and volatile organic compounds (VOCs), while soil and water pollutants may comprise of organic substances (pesticides, insecticides, phenols, hydrocarbons, etc.), heavy metals (lead, cadmium, arsenic, mercury, etc.), as well as microbial pathogens. These environmental pollutants have a great potential to adversely influence the human health (Fereidoun et al. 2007; Kampa and Castanas 2008), since they can find their way into human body either through inhalation, ingestion, or absorption. In addition to that, some of these toxicants tend to accumulate in food chains, such as the bioaccumulation of heavy metals (Kumar et al. 2011; Smical et al. 2008; Yap et al. 2011) and persistent organic pollutants (POPs) (Bayen et al. 2005; Houde et al. 2008; Kelly et al. 2007) in biota and fishes, which poses major risks to human and wildlife. Therefore, there is an exigent demand for the improvement of sustainable, efficient, and low-cost technologies to monitor and properly treat toxic environmental pollutants.
One of the most promising approaches to revolutionize the environmental remediation techniques is “nanotechnology” which can be defined as a group of emerging technologies that work on nanometer scale (i.e., between 1 and 100 nm range) to produce materials, devices, and systems with fundamentally new properties and functions by controlling the size and the shape of matters (Mansoori and Soelaiman 2005; NSTC/NNI/NSET August 29 2003; Ramsden 2009). The global momentum of nanotechnology due to its potential applications that are covering many fields (e.g., medicine (Kiparissides and Kammona 2015; Müller et al. 2015; Usui et al. 2008), food industry (Duncan 2011; Shanthilal and Bhattacharya 2014), energy (Hussein 2015; Serrano et al. 2009; Zang 2011), pollution treatment (Brame et al. 2011; Karn et al. 2009)) is offering leapfrogging prospects in the improvement and transformation of conventional remediation technologies.
Different processes (including photocatalytic deposition (PD) deposition–precipitation (DP), chemical vapor decomposition (CVD), chemical solution decomposition (CSD), wet chemical method, sol–gel, ultrasonic irradiation, thermal and hydrothermal processes, etc.) (Khajeh et al. 2013) have been used to synthesize various types of nanomaterials that exhibit unique merits different from that of their bulk counterparts. The extraordinary properties such as thermal, optical, mechanical, electromagnetic, structural, and morphological properties (Loos 2015) provide the nanomaterials with advantageous features for many applications where they can be utilized as nanoadsorbents, nanosensors, nanomembrane, and disinfectants. Furthermore, many attempts were reported to synthesize more sophisticated nanostructure (e.g., nanorods, nanobelts, nanowires, nanofibers, etc.) in order to increase the versatility of nanomaterials and to overcome all the challenges that hinder their applications (Aguilar 2013). In view of the remarkable advances in nanotechnology and the urgent need to develop green, robust, and economic approaches for environmental remediation, this paper highlights the auspicious nanomaterial applications in air, soil, and water and provides a broader view on favorability of nanotechnology over the conventional technologies in wastewater treatment systems.
Air pollution
Air pollution is one of the world’s most significant problems, and it can be defined as the alteration in the natural composition of the atmosphere that is caused by the introduction of chemical, physical, or biological substances that are being emitted from anthropogenic, geogenic, or biogenic sources (Daly 2007). The poor air quality has an adverse impact on ecosystem (e.g., vegetation and living organisms) and on the human health by possibly causing various types of diseases which can be fatal, such as cancer, respiratory, and cardiovascular diseases. The World Health Organization (WHO) in 2014 reported that around seven million people died in 2012 due to air pollution exposure.
Outdoor air pollution
The most important outdoor air pollution problem is global warming that leads to many changes in the atmosphere, land, and water sources all over the world. Greenhouse gases (GHGs) are considered the direct contributors to the global warming. The main greenhouse gases are carbon dioxide, methane, nitrous oxide, and fluorinated gases. The problem of GHG emission is exacerbating by the growing human activities (Metz et al. 2007). The majority of the greenhouse gases have persistent long-term effects on climate due to their tendency to stay in the atmosphere for hundreds of years. Many of control and treatment technologies have been developed to eliminate and monitor the emission of these gases and to eliminate their risks on human and the environment. Nanotechnology is a well-enabled treatment technology to control and remediate air pollution in several ways by taking advantage of nanomaterial properties and applying them as adsorbents, catalysts, membranes, and sensors (Zhao 2009).
As can be noticed from Fig. 1, carbon dioxide represents 75 % of GHGs in the environment; thus, several techniques have been proposed to control its emission either by separation or capturing, such as filtration, absorption in liquids, adsorption on solids, or a combination of these processes (Cheung et al. 2013). The adsorption on nanomaterials is proved to be more efficient and cost-effective process due to the high surface area of nanomaterials that can significantly enhance the adsorption capacity, as well as the availability of nanomaterials and their ability to be regenerated. The solid adsorbents for capturing carbon dioxide can be divided into three classes: (1) the high temperature adsorbents (>400 °C), (2) the intermediate temperature adsorbents (200–400 °C), and (3) the low temperature adsorbents (<200 °C) (Upendar et al. 2012).
Calcium (Ca)-based nano-adsorbents are used to capture carbon dioxide at high temperature based on the reversible carbonation reaction of calcium oxides (CaO). The serious disadvantage of using the high temperature adsorbents lies in their ability to aggregate easily leading to a sintering problem during the carbonation/calcination cycles (Abanades and Alvarez 2003). As a result, surface coating of the Ca-based nano-adsorbents is used to prevent the aggregation of these adsorbents and consequently avoid the sintering problem. Wang et al. (2013c) reported that titanium dioxide (TiO2)-coated nano calcium carbonate can prevent the sintering of nano calcium carbonate and effectively capture carbon dioxide using the adsorption phase technique.
Moreover, the treated nanoparticles with alkali metals (Li, Na, K, Cs, Fr) showed the ability to capture carbon dioxide at high temperature, for instance nano-sized citric acid pretreatment rice husk ash (CRHA) lithium ortho-silicate based (CRHA-Li4SiO4) adsorbents exhibited a sintering-resistant character and captured carbon dioxide (CO2) at 700 °C (Wang et al. 2014a). Furthermore, the alkali nanotubes (e.g., potassium titanate (K-Ti-NT) and sodium titanate (Na-Ti-NT)) have been used to capture carbon dioxide at low temperature (below 200 °C) (Upendar et al. 2012). Another example of CO2 low temperature adsorbents is carbon-based materials (CNMs). They are used widely due to their high surface and high amenability to pore structure modification and surface functionalization (Upendar et al. 2012). Functionalized carbon nanotubes (CNTs) have been successfully used to capture CO2 and enhance the adsorption performance in the presence of moisture, which decline the adsorption capacity due to water molecules competing with CO2 for the active adsorption sites (Jänchen et al. 2007). Su et al. (2009) pointed out that functionalization of carbon nanotubes by 3-aminopropyl-triethoxysilane (CNTs-APTS) grafted the surface of CNTs with abundant amine groups that provide numerous chemical sites for CO2 adsorption which makes CNTs adsorb more CO2 gases at low temperature range (20–100 °C). In addition, it was suggested that there are two possible reasons for the increase of (CNTs-APTS) adsorption capacity in the presence of moisture and they are (1) CO2 gas may dissolve into the adsorbed water on the surface of (CNTs-APTS) and (2) the reaction between CO2 and surface amino groups forms carbonate ions which may undergo further reaction with CO2 and water to form bicarbonate (HCO3 −) (or the amino groups itself can also directly react with CO2 and H2O to form HCO3) (Su et al. 2009).
As another illustration of nanotechnology role in GHG treatment, many catalytic processes have been devoted for conversion or decomposition of methane (CH4) and nitrous oxides (NO x ). For instance, metallic nickel nanoparticles were employed as catalysts for thermal decomposition of methane to produce hydrogen (Wang and Lua 2012), and TiO2 coated with stainless steel web net was efficiently used for photocatalytic degradation of (CH4) (Merajin et al. 2013). On the other hand, titanate nanotubes (TNTs) and their derivatives have been widely reported for the photocatalytic oxidation of NO x . Many studies attempted to obtain the optimum parameters that effect the decay rate and the removal efficiency of NO x . For example, Nguyen and Bai (2015) have proved that the surface area, the amount of crystalline, and the remnant sodium content of TNTs increased by washing at pH 3–5 and accordingly increased the removal efficiency of both NO and NO2. Moreover, modified TiO2 with different loads of silver was used for the photocatalytic decomposition of (N2O) to nitrogen and oxygen (Obalová et al. 2013). The silver deposited on the surface of TiO2 provokes a decrease in the electron-hole recombination rate (Kočí et al. 2012).
In addition to GHGs, sulfur dioxide is one of the industrial emissions that is linked to different environmental problems and serious human health risks. Nanomaterials have been used to eliminate SO2 release to environment either by desulfurization of fossil fuel (Saleh et al. 2015) or by its removal directly from the emission source by various technologies, such as adsorption processes (Wu et al. 2011) and catalytic oxidations (Koutsopoulos et al. 2006; Rodriguez et al. 2010). Removal of SO2 occasionally leads to some changes in the morphology or characteristics of the used materials. For instance, during the application of activated carbon with deposited iron nanoparticles as adsorbent, formation of weakly acidic groups on the adsorbent surface was involved with the SO2 adsorption process which increases the surface acidity (Arcibar-Orozco et al. 2013). Moreover, it was proved that SO2 adsorption process can lead to clear changes in magnetism when using magnetic nanoparticles (MNPs). For example, SO2 adsorption on the surface of COFe2O4 MNPs leads to a decrease in their saturation and remnant magnetization by approximately 20 % and a decrease in their coercivity by approximately 9 % (Glover et al. 2012). Table 1 shows more examples of nanomaterials used to treat different types of air pollutants.
Indoor air pollution
Indoor air pollution has recently become a major concern due to its direct effects on human health (MR 2009; Solomon et al. 2008). Among the indoor air pollutants are VOCs which are believed to be the main cause of increasing childhood asthma, atopic hypersensitivity, as well as other series of symptoms, such as headache, nausea, coryza, pharyngitis, emphysema, and lung cancer (Lee et al. 2010a, b). Therefore, it is strongly required to progress an effective method to control and eradicate the emission of these VOCs (Hauptmann et al. 2004).
The most abundant airborne carbonyl chemical is formaldehyde (HCHO), which is a well-known precursor in manufacturing of more complex materials, such as phenol-formaldehyde and urea-formaldehyde resins, that are broadly used as wood-binding products and insulating foam. Several methods are used for the removal of formaldehyde, including decomposition by which photocatalysts and physical adsorption by porous materials are used, as well as chemical adsorption which is considered one of the effective methods where the re-emission is excluded due to strong chemical bonding (Nuasaen et al. 2014). However, HCHO imposes great challenges for its removal. For example, conventional photochemical methods using photocatalysts are not appropriate for the indoor removal of HCHO because of the requirement of UV light irradiations and the risk of harmful ozone formation (Miyawaki et al. 2012). Moreover, hydrocarbon compounds could generate carcinogenic by-products through chains of secondary photochemical reactions (Miyawaki et al. 2012).
As a result, many attempts have been carried out to improve the removal of formaldehyde, for example, Lee et al. (2010a, b) produced electrospun polyacrylonitrile (PAN)-based carbon nanofiber (CNF) membrane with tailored microporosity and abundant nitrogen-containing functional groups as vastly effective adsorption sites. A notable amount of formaldehyde was adsorbed onto the PAN-activated carbon nanofiber (ACNF) pore surface even at a low concentration. However, air humidity reduced the life time of the nanofiber membrane to half. As a result, manganese oxide (MnO x ) catalysts were deposited on the PAN-ACNFs. The combination of MnO x with PAN-ACNF afforded a superior formaldehyde removal performance in dry and extremely humid conditions by applying a two-stage removal process, comprised of the adsorption of formaldehyde in the PAN-ACNF micropores followed by the oxidative decomposition by MnO x nanoparticles without any irradiation of UV light (Miyawaki et al. 2012).
An additional example on indoor air pollutants that have received social and scientific attentions is bioaerosols (aerosols of biological origin such as viruses, bacteria, and fungi) which can rapidly spread with airflow and can cause numerous diseases, including infections and allergies (Stark et al. 2003). Air filtration technology using antimicrobial materials such as silver nanoparticles, copper nanoparticles, CNTs, and natural products is considered the most applied and effective technique to remove bioaerosols through ventilation processes. Several studies have exposed that silver nanoparticles can successfully remove bacterial bioaerosols during the air filtration process. Several factors affect the antimicrobial activity of silver nanoparticles such as bacterial species, concentration, relative humidity (RH), size distribution, and exposure time of the silver nanoparticles (Lee 2008a; Lee et al. 2010a). In a like manner, the inactivation efficiency of CNTs is dependent on the loading concentration and membrane pore size, and it is low for single-walled carbon nanotubes (SWCNTs) compared to that of multi-walled carbon nanotubes (MWCNTs) (Jung et al. 2011).
Despite the efforts to improve indoor air quality (IAQ), the human exposure to nanomaterial-based filters in indoor environments may lead to variety of adverse health effects, including peribronchial inflammation and necrosis, skin irritation, and mucosal inflammation (Lam et al. 2004; Warheit et al. 2007). In comparison to some antimicrobial materials such as silver, carbon nanotubes, and metal oxides, the antimicrobial natural products are typically considered less toxic to human and have recently been used to improve the IAQ. For example, essential oils extracted from natural products show acceptable reduction rates in bacterial inactivation; therefore, they have been applied to ventilation systems of indoor-contaminated environments (e.g., an antimicrobial filter coated with tea tree oil inactivates 99 % of bacterial aerosol on its surface within 2–8 min) (Pibiri et al. 2006; Pyankov et al. 2008). Some of natural nanoparticles (e.g., Sophora flavescens) have been deposited on the filter media surface using an aerosol process, yet they lost their spherical shape and coalesced on fiber filters under humid conditions (Hwang et al. 2012). In consequence, the electro-spraying method, driven by high-intensity electric fields, is used to generate the natural product nanoparticles in order to increase their morphological stability and eventually increase the produced filter efficiency for bioaerosol removal (Jung et al. 2013). Thus, the implementation of filters generated from electro-spraying natural products can be a promising new technology to control air quality.
Soil pollution
Soil contamination is caused by the existence of hazardous compounds in the natural soil environment. The common soil pollutants are heavy metals which can be presented naturally in soil but scarcely at toxic levels, and their main sources in contaminated soil are mining, manufacturing, landfill sites, particularly those that are accepting industrial wastes (e.g., paint residues, batteries, electrical wastes, etc.), and municipal or industrial sludge. Heavy metals can be considered one of the challenging soil pollutants because they are non-degradable substances, and they will stay in the contaminated environment once they are introduced to it; the only exceptions are mercury and selenium, since they can be transformed and volatilized by microorganisms. When large areas of soil are polluted, treatments can be done in situ (on-site) or ex situ (removed and treated off-site); however, the traditional treatment methods for contaminated soil are cost-prohibitive and extremely difficult (Natural Resources Conservation Service 2000). As a result, the best way to protect the environment is by preventing the contamination of heavy metals or by hindering the spreading of heavy metals in soil by immobilization technique (Ma et al. 1993).
Due to the fact that activity of heavy metals in soil is governed by sorption–desorption reactions with other constituents of soil (Singh et al. 2001), wide range of amendment agents have been used to manipulate the bioavailability of heavy metals and to impede their diffusion in soil by inducing various sorption processes: adsorption to mineral surfaces, formation of stable complexes with organic ligands, surface precipitation, and ion exchange (Kumpiene et al. 2008). There are two types of amendment agents (Robinson et al. 2009): (1) mobilizing agents, which increase the bioavailability and mobility of heavy metals and enhance their removal through plant intake and soil washing (i.e., phytoextraction process), and (2) immobilizing amendment agents that decrease the bioavailability and mobility of heavy metals and reduce their transfer to food chain by preventing their leaching to the groundwater (i.e., phytostabilization) (Fig. 2). Both phytoextraction and phytostabilization processes are part of phytoremediation technique that is employed to manage contaminated soils (Bolan et al. 2014).
In recent years, nanoscale particles have gained a great interest for heavy metal immobilization in soil and groundwater. Two essential requirements should be met when using nanoparticles as amendment agents including the following (An and Zhao 2012): (1) they must be deliverable to the contaminated zones and, (2) when removing the external injection pressure, the delivered nanoparticles should remain within the confined domain (i.e., under natural groundwater conditions), where the delivered nanoparticles will work as an immobile sink for capturing soluble metals. However, the rapid tendency of nanoparticles to aggregate into micro- to millimeter scale aggregates results in losing their distinctive characteristics such as high specific surface area and soil deliverability. For the purpose of overcoming these problems, organic polymers such as starch (He and Zhao 2005) and carboxymethyl cellulose (CMC) (He and Zhao 2007) are often attached on the nanoparticles as stabilizers in order to prevent nanoparticle agglomeration through steric and/or electrostatic stabilization mechanisms and to improve the physical stability and mobility in soil and greater specific surface area. Liang and Zhao (2014) investigated the effectiveness of starch-stabilized magnetite nanoparticles for in situ enhanced sorption and immobilization of arsenate As(V); the results indicated that water-leachable As(V) was greatly reduced as well as the toxicity characteristic leaching procedure (TCLP) leachability of As(V) was decreased.
Phosphate compounds can be used as effective agents for in situ immobilization of heavy metals in contaminated soils, as demonstrated by immobilization of lead (Pb) where phosphate was commonly applied to soil either in its soluble forms such as phosphoric acid or solid forms such as synthetic apatite, natural phosphate rocks, and even fishbone (with apatite being the effective composition) (Yang et al. 2001). Therefore, a new type of apatite nanoparticles was synthesized using CMC as a stabilizer in order to increase the dispersion rate of phosphate and immobilize lead in soil. It was suggested that the carboxyl and hydroxyl groups in cellulose molecules played an important role in inhibiting further agglomeration of nanoparticles; moreover, in producing a stable lead phosphate compound, that is widely recognized as pyromorphite (Liu and Zhao 2013).
Zerovalent iron (ZVI) nanoparticles are also used widely for in situ reductive immobilization of heavy metals in soil. The main drawback of ZVI nanoparticles that are prepared using traditional methods is their ability to agglomerate rapidly or react quickly with the surrounding media (e.g., dissolved oxygen or water), resulting in losing in their reactivity and mobility in soil. The agglomerated ZVI particles are often in the range of micron scale; therefore, they are not transportable or deliverable in soils, and thus, they are not applicable for in situ treatments. Accordingly, various ZVI particle-stabilizing strategies have been reported including modification of nZVI with several types of organic coatings, such as starch (Reyhanitabar et al. 2012), polyvinylpyrrolidone (PVP), (Fang et al. 2011a) and sodium CMC (He and Zhao 2007). Cetylpyridinium chloride has also been used to control ZVI nanoparticle agglomeration (Chen et al. 2004). Another problem that is limiting the engineering applications of iron-based materials is the cost factor due to the large amount of chemical reagents such as ferrous sulfate and ferrous chloride that are consumed during the material conventional preparation technologies (Fang et al. 2011b). With intention to reduce the cost, Wang et al. (2014c) successfully prepared CMC-stabilized nanoscale zerovalent iron from steel pickling waste liquor to remove Cr(VI) from contaminated soil, and the results revealed that TCLP leachability of Cr(VI) reduced by 100 %. Moreover, Table 2 displays some of used nanomaterials to remove different types of soil contaminants.
However, the immobilization technique to remediate the contaminated soil imposes many problems. Firstly, despite of both soluble and solid phosphates being reported as highly effective for heavy metal in situ stabilization on the laboratory scale, adding large amounts (e.g., 3 % PO3 −4 dosage) of very soluble phosphoric acid or phosphate salts into the subsurface is limited not only by the cost of materials but also by the secondary contamination problems that arise due to the high solubility of phosphate which may lead to the contamination of groundwater and surface waters in the affected area by excessive nutrient input (eutrophication) (Park et al. 2011). Secondly, Xu and Zhao (2007) stated that the CMC stabilizer is vulnerable to hydrolysis and, once it decomposes, its particle-stabilizing ability ceases and the fine residual precipitates end up in the soil phase. Finally, Wang et al. (2014b) investigated the ecotoxicity of the immobilized chromium by CMC-stabilized ZVI nanoparticles prepared from steel pickling waste. The results suggested that such remediation exerted an inhibitory effect on plant growth, which might be related to specific physicochemical properties of nZVI. There are several possible mechanisms by which fresh nZVI could enhance Fe uptake into plants; one possibility is that they penetrate the seed coat and are assimilated by the seed embryo (Wang et al. 2014b). Another expected way for nZVI to enter the plant is via root epidermal cells by endocytosis (Slomberg and Schoenfisch 2012). Moreover, it was confirmed that carbon nanotubes are also able to penetrate the seed coat while supporting and allowing water uptake inside the seeds (Khodakovskaya et al. 2009).
Water pollution
One of the major challenges that is facing the globe is providing a convenient access to clean and affordable water that can keep up with rapidly growing demands. Population growth, global climate change, and water pollution are the highest challenges that increase the struggles faced by water supply systems. In both developing and industrialized countries, water scarcity is exacerbated by human activities that play the greatest role in contaminating the natural water resources by releasing energy, chemicals, and other pollutants that deteriorate the water quality for other users. In addition, nature itself can be one of the contamination sources such as water storm runoff, animal wastes, etc. The United States Environmental Protection Agency (EPA) classifies water pollution into the following six categories: (1) plant nutrients, (2) biodegradable waste, (3) heat, (4) sediment, (5) hazardous and toxic chemicals, and (6) radioactive pollutants. Thus, water pollutants include organic pollutants, pathogens, industrial discharge containing heavy metals and different anions, etc. (Goyal et al. 2013) that are added to the water and cannot be naturally broken down and they tend to change the properties of the water body.
Essentially, the wastewater treatment involves physical, chemical, and biological technologies and it usually occurs in four stages: (1) preliminary, (2) primary, (3) secondary, and (4) tertiary advanced treatment. The technologies that are generally used for water purification are coagulation and flocculation, sedimentation, dissolved air flotation, filtration, steam distillation, ion exchange, deionization, reverse osmosis, and disinfection (Shon et al. 2007). Materials usually used in these technologies are sediment filters, activated carbon, coagulants, ion exchangers, ceramics, activated alumina, organic polymers, and many hybrid materials (Hotze and Lowry 2011). However, the conventional water treatment procedures might be costly and could release secondary toxic contaminants into the environment (Gaya and Abdullah 2008a).
Nanotechnology enables extremely efficient, flexible, and multifunctional processes that can provide a promising route, in order to retrofit aging infrastructure and to develop high performance, inexpensive treatment solutions which depend less on large infrastructures (Qu et al. 2013b). The current advancements in nanotechnology spot the light on great opportunities to develop the next generation of water supply systems and expose the possibilities to expand the water supplies by affording new and cost-effective treatment capabilities that can overcome the major challenges faced by the current treatment technologies (Qu et al. 2013a).
Adsorption
Compared to the limited active site surface area and low efficiency of the conventional adsorbents, the nano-adsorbents offer a considerable advancement with their high adsorption kinetics as demonstrated by their extremely high specific surface area and associated sorption sites, short intraparticle diffusion distance, and tunable pore size and surface chemistry (Qu et al. 2013a) that provide useful features for effective adsorption. Their great adsorption capacity is mainly because of their high specific area and the highly active adsorption sites that are created by high surface energy and size-dependent surface structure at the nanoscale (Auffan et al. 2008). The nanoadsorbents are effectively used in the removal of organic compounds, and metal ions and their selectivity toward particular pollutants can be increased by functionalization.
Nanoscale metal oxides, such as titanium dioxides, iron oxides, zinc oxides, alumina, etc., have been explored as low-cost, effective adsorbent for water treatment offering a more cost-efficient remediation technology due to their size and adsorption efficiency (Engates and Shipley 2011; Zhang 2003). The adsorption is chiefly controlled by forming a complex with the surface of nanoscale metal oxides and undergoing one electron oxidation reaction under visible irradiation (Peng et al. 2012a). Among the nanoscale metal oxides, the magnetic nanoparticles have drawn a considerable concern because of their potential application (Xin et al. 2012) and their exhibition of interesting magnetic properties (e.g., super paramagnetism, strong magnetic response under low applied magnetic fields (Fig. 3) (Kilianová et al. 2013). Table 3 shows the applications of nanoscale metal oxides as adsorbents.
Not to mention that CNTs, including single-walled CNTs and MWCNTs, have lately drawn significant attention because of their mechanical, electrical, optical, physical, and chemical properties (Koziol et al. 2007). Since CNT discovery by Iijima in 1991 (Iijima 1991), they have been recognized as alternates for activated carbon as they exhibit remarkable adsorption competency for gas and liquid phases, such as organic vapors, inorganic pollutants, and several heavy metal ions (Luo et al. 2013a) due to their binding sites that are more available than those on activated carbon (Ji et al. 2009).
In comparison to other carbon-based adsorbents, CNTS is the super organic adsorbent for environmental remediation; they behave as flexible porous materials toward the organic pollutants. CNTs have shown remarkable adsorption capability and high removal efficiency for various organic pollutants (Table 4), including organic dyes (e.g., cationic, azoic, reactive, basic and acid dyes, etc.) (Bazrafshan et al. 2012; Gao et al. 2013; Geyikçi 2013; Gong et al. 2009; Gupta et al. 2013; Madrakian et al. 2011; Moradi 2013), pharmaceuticals (e.g., cephalexin, tetracycline (TC), olaquindox, carbamazepine, etc.) (Cai and Larese-Casanova 2014; Jafari and Aghamiri 2011; Zhang et al. 2011a, b), pesticides (Chen et al. 2011a; Deng et al. 2012), phenolic compounds (Abdel-Ghani et al. 2014; Chen et al. 2009b; Lin and Xing 2008; Pacholczyk et al. 2011; Sheng et al. 2010b), and other toxic organics. Apul and Karanfil (2015) and Yu et al. (2014) reported the adsorption of many different types of organic compounds on carbon nanotubes. The dominate adsorption mechanisms by which CNTs adsorb organic compounds consist mainly of physical processes and are affected by the properties of the compound of interest (Pan and Xing 2008). Lin and Xing (2008) and Ren et al. (2011) stated that the aromatic compounds have relatively higher sorption affinity toward CNTs than non-aromatics. Furthermore, organic compounds which have −COOH, −OH, and −NH2 functional groups could also form hydrogen bond with the graphitic surface of CNTs (Yang et al. 2008). In short, during organic compound–CNT interactions, different mechanisms may take place simultaneously such as hydrophobic interactions, π–π bonding, electrostatic interactions, and covalent and hydrogen bonding (Gupta et al. 2013; Pan and Xing 2008; Yang and Xing 2010).
On the other hand, CNTs have shown great capabilities for the adsorption of heavy metals from natural waters and wastewater streams and that is of great environmental relevance due to the high toxicity and non-biodegradability of compounds which are generally considered as carcinogenic (Luo et al. 2013a). Many researches have investigated the mechanisms of heavy metal ion adsorption on CNTs which appear to be very complicated and attributable to physical adsorption, electrostatic attraction, precipitation, and chemical interaction between the heavy metal ions and the surface functional groups of CNTs (e.g., carboxyl, hydroxyl, lactones, and phenol) (Ren et al. 2011), whereas the chemical interaction between the heavy metal ions and the surface functional groups of CNTs is the main adsorption mechanism and that reflects that the sorption of metal ions onto CNTs is chemisorption process rather than physisorption process and strongly depends upon CNT surface total acidity (Lu et al. 2006; Lu and Liu 2006; Rao et al. 2007). The adsorption of the heavy metals might be influenced by the presence of some organic compounds, for instance, the adsorption of copper(II) is significantly influenced by humic acid (HA), fulvic acid (FA), and hydroxylated and carboxylated fullerenes (Sheng et al. 2010a; Wang et al. 2013a). The order of binding of heavy metal ions by CNTs is widely studied. Stafiej and Pyrzynska (2007) reported the adsorption characteristics of certain divalent metal ions (i.e., Cu, Co, Cd, Zn, Mn, and Pb) by MWCNTs and found that the affinity of metal ions for MWCNTs followed the order Cu(II) > Pb(II) > Co(II) > Zn(II) > Mn(II). Meanwhile, Li et al. (2003a) studied the competitive adsorption of Pb(II), Cu(II), and Cd(II) ions by oxidized MWCNTs and found that the adsorption capacities of MWCNTs for the three metal ions were in the following sequence: Pb(II) > Cu(II) > Cd(II). Table 5 represents carbon nanotube as heavy metal adsorbent.
The main drawback of CNTs is the poor dispersion in the aqueous phase that significantly hinders the application of CNTs because of the hydrophobicity of their graphitic surface and the strong intermolecular van der Waals interaction between tubes, which can lead to the formation of loose bundles/aggregates (Fig. 4) that contain interstitial spaces and grooves which are reported to be high adsorption energy sites for organic molecules (Pan et al. 2008), and despite of that, it was suggested that those aggregates reduce the effective surface area of CNTs (Vuković et al. 2010a). In order to overcome this drawback and enhance the CNT performance, it can be functionalized in different ways, for example formation of chemical bonds between the modifier and CNT surfaces or physical adsorption of the modifying species to the surface of CNTs and all the ways lead to the addition of functional groups on the surface of the CNTs improving their efficiency, selectivity, and sensitivity (Ghaedi and Kokhdan 2012; Han et al. 2006; Liu et al. 2008; Perez-Aguilar et al. 2011; Tasis et al. 2006; Wildgoose et al. 2006). The acid treatment produces carboxylic and hydroxylic group (COOH, OH, C=O, and OSO3H) on the external surface of the CNTs (Vuković et al. 2010a) as shown in Fig. 5. The hydrophilic groups (i.e., carboxylic groups) can be introduced onto the sidewall of CNTs, as a result improving the solubility and dispersion of CNTs in aqueous solutions (Liu et al. 1998). Functionalization of CNTs via oxidizing and reducing chemicals such as HNO3, KMnO4, H2O2, NaClO, H2SO4, KOH, and NaOH has been widely reported (Li et al. 2010; 2003b; Raymundo-Piñero et al. 2005).
Another essential point is the separation of CNTs from the treated medium that may cause considerable inconvenience in their practical application. In order to cope with this problem, magnetic CNTs have been prepared by association of CNTs with magnetic nanoparticles and they can be well dispersed in the water as well as can be simply manipulated by external weak magnetic field that permits their easy separation from water (Peng et al. 2005; Qu et al. 2008). Thus, it was demonstrated that combining the magnetic properties of the iron oxides with the adsorption properties of CNTs is an effective and rapid method for the separation of the magnetic adsorbents from aqueous solutions (Gong et al. 2009; Gupta et al. 2011; Lu et al. 2011). Despite of that, the magnetic phase can be leached out in acidic media because they are placed within the pores which do not protect them from contact with solution. Bystrzejewski and Pyrzyńska (2011) pointed out that carbon-encapsulated magnetic nanoparticles (CEMNPs) are free of this disadvantage, because they comprise of uniform spherical nano-crystallites firmly covered by tight carbon coatings. The role of the coatings is to protect the encapsulated nanoparticles from agglomeration and corrosion and to provide a scaffold for introducing surface acidic groups that are important to bind the metal ions (Bystrzejewski et al. 2009; Pyrzyńska and Bystrzejewski 2010).
Membrane processes
Membrane process has been proven to be an effective way for water remediation because of its high separation efficiency, easy operation where no chemical addition or thermal input is required, and it does not lead to secondary pollution as well as no regeneration of spent media is required (Balamurugan et al. 2011; Buonomenna 2013; Pendergast and Hoek 2011). The performance of the membrane system is basically influenced by the membrane material, which affords an inherent tradeoff between membrane selectivity and permeability. The common membrane materials applied for water treatment are polymers, for instance cellulose acetate (CA), polyacrylonitrile (PAN), and polyamide (PA) (Yang et al. 2009a). Based on the pore size and filtration application, the membrane process can be classified as microfiltration (MF) for suspended solids, protozoa, and bacteria removal, ultrafiltration (UF) for virus and colloid removal, nanofiltration (NF) for hardness, heavy metals, and dissolved organic matter removal, and for desalination, water reuse, and ultrapure water production (reverse osmosis (RO) and forward osmosis (FO)) (Balamurugan et al. 2011; Bernardo et al. 2009; Ulbricht 2006).
Over the past decade, nanotechnology has led to new water treatment membranes by incorporation of nanomaterials into membranes either by blending or surface grafting for producing membranes with desirable structure and new functionality such as high permeability, catalytic reactivity, contaminant degradation, and self-cleaning (Pendergast and Hoek 2011), moreover, controlling membrane fouling due to nanoparticles functional groups and their hydrophilic properties (Vatanpour et al. 2012).
Nanofibrous membranes
Polymer or composite nanofibrous membranes can be generated using electrospinning method which is versatile and efficient technique to compose ultra-fine fibers using various materials (e.g., polymers, ceramics, or even metals) with diameters in the range of 20–2000 nm (Cloete 2010; Li and Xia 2004; Li et al. 2013; Yang et al. 2009a). Electrospun nanofibrous membranes have large specific surface area (Balamurugan et al. 2011), fine tunable pore size (Ramakrishna et al. 2006), as well as high water flux that attracted both industry and academic researchers to study their application for MF and UF (Gopal et al. 2006, 2007). The researches revealed that nanofiber membranes can sufficiently remove micron size particles from aqueous solutions at high rejection rate and without a significant fouling; therefore, the membrane could be successfully recovered upon cleaning (Ramakrishna et al. 2006).
The electrospun nanofibers can be simply manipulated for particular application and used as affinity membrane to remove heavy metals and organic pollutants during filtration by the introduction of certain functional groups (Li and Xia 2004; Li et al. 2013; Qu et al. 2013a). The nanofibers are functionalized by covalently attaching ligands onto the surface, for example, using cibacron blue to functionalize cellulose nanofiber membranes for albumin purification (Ma et al. 2005), functionalization of polymer nanofibers membranes with a ceramic nanomaterials such as hydrated alumina/alumina hydroxide and iron oxide for removal of heavy metal ions by adsorption/chemisorption and electrostatic attraction mechanisms (Ramakrishna et al. 2006), and introduction of cyclodextrin into a poly(methyl methacrylate) nanofiber membrane to enhance their affinity for organic waste removal (KAUR et al. 2006).
Nanocomposite membranes
Although the membrane separation technology plays a remarkable role in water and wastewater treatment, membrane fouling is still the main shortcoming that reduces the lifetime of the membrane and limits its application due to the increasing of energy consumption, operating costs, and difficulty of process operation (Balta et al. 2012). The membrane fouling can be classified into organic fouling and biological fouling and both are responsible for the flux decline in the membrane processes (Meng et al. 2009). The main reason of membrane organic fouling is the abundance of natural organic matters (NOM) in water that are adsorbed and deposited on the surface of the membrane leads to the blockage of the pores forming a cake layer on the surface (Lee et al. 2004; Meng et al. 2009). Next, the leading cause of the biological fouling is the adhesion of bacteria to the membrane surface producing a sticky biofilm composed of polysaccharide, organic chemicals, and a complex community of microbial cells resulting in biofouling which is considered a serious problem due to the ability of bacteria to reproduce at the surface of the membrane, forming biofilms and producing an additional fouling which is difficult to be removed (Bjørkøy and Fiksdal 2009; Ciston et al. 2009; Herzberg and Elimelech 2007; Sawada et al. 2012; Wang et al. 2005). With regards to the causes of both organic and biological membrane fouling and their severe consequences, it is important to improve the antifouling and antibacterial properties of the membranes.
The fouling of the membranes is affected by their morphology, charge, as well as the hydrophobicity of the membranes (Gray et al. 2008; Sun et al. 2009; Weis et al. 2005). Many studies have proven that the membrane shows stronger resistance to substance adsorption when increasing its surface hydrophilicity; therefore, modifying the membrane hydrophobicity can be an effective technique to improve its organic antifouling (Arahman et al. 2009; Rahimpour and Madaeni 2007; Wang et al. 2006).
Many efforts have been devoted to study a number of modification methods in order to improve the hydrophilicity and reduce membrane fouling, involving coating (Razmjou et al. 2011b), grafting (Rahimpour 2011), and blending with hydrophilic metal oxide nanoparticles which is proven to be an effective method to obtain nanocomposite membranes without complicated operation process (Yu et al. 2013). The blending of metal oxide nanoparticles includes alumina (Maximous et al. 2010b; Yan et al. 2006), zirconium dioxide (Bottino et al. 2002; Maximous et al. 2010a; Pang et al. 2014), silica (Bottino et al. 2001; Jin et al. 2012; Shen et al. 2011; Yu et al. 2013), zeolites (Pendergast et al. 2010), and titanium dioxide (Rahimpour et al. 2008; Razmjou et al. 2011a, 2012). It was highlighted that the addition of metal oxides nanoparticles does not affect the membrane structure, while it obviously enhances the performance of the membrane (Shen et al. 2011) as well as its thermal stability (Ebert et al. 2004; Pendergast et al. 2010). Additionally, functionalized MWCNTs were successfully blended with polymer membranes. The membrane, permeability, hydrophilicity, and fouling resistance were significantly improved by the functional groups on MWCNTs which are embedded in membrane nanocomposite (Choi et al. 2006b; Daraei et al. 2013).
Another prerequisite argument is preventing the development of biofilms on membrane surface; thus, many antimicrobial nanoparticles have been studied to endow the membrane with a self-antimicrobial property. For example, silver nanoparticles (nano-Ag) have been exploited to inactivate viruses (De Gusseme et al. 2011), mitigate the bacterial growth, and inhibit biofilm formation (Mauter et al. 2011; Zodrow et al. 2009) not only by being coated or grafted on the surface of the membranes but also by being blended in the membrane fabrication process (Zodrow et al. 2009). Ag-nanocomposite membranes showed significant antibacterial properties toward Escherichia coli (Zodrow et al. 2009) (Obalová et al. 2013), with antibacterial efficiency about 99.999 % (Sawada et al. 2012). Another nanomaterial integrated into membranes as antimicrobial agent is SWCNTs. The antibacterial activity of SWCNTs-nanocomposites was investigated, and the results exposed that high bacterial inactivation (>90 %) was attained by the SWCNTs-nanocomposites reducing the growth of biofilms on the surface of the membranes (Ahmed et al. 2011).
It is important to point out that photocatalytic nanoparticles, namely TiO2 which has drawn a significant attention due to its stability and promising applications as photocatalysis (Cao et al. 2006), have been used to develop photocatalytic nanocomposite membranes (reactive membranes) with higher hydrophilicity (Li et al. 2014b), improved fouling resistance, and thermal stability (Wu et al. 2008) coupled with their ability to combine their function of physical separation and the reactivity of a catalyst toward pollutants degradation (Bae and Tak 2005; Choi et al. 2006a; Kim et al. 2003). In addition to that, metallic/bi-metallic nanoparticles precisely nano zerovalent iron (nZVI) which serves as electron donor and catalyst (Qu et al. 2013a; Wang et al. 2013b) have also been integrated into membranes for reductive dechlorination of contaminants mainly chlorinated organic compounds (COCs) (Wu and Ritchie 2008; Wu et al. 2005). Finally, although nanoparticles are very effective for environmental remediation and enhancement of the performance of membrane process, they tend to leach out and aggregate especially if they were grafted on the membrane without surface protection and that might complicate the operation and decrease the contaminant degradation. Consequently, many studies have investigated the possibilities to employ mediation (Li et al. 2014b) or solid supports (Wang et al. 2008b) for immobilization of the nanoparticles in order to overcome the aforementioned shortcomings.
Osmotic membranes
Both RO and FO exploit semi-permeable membrane for water purification and desalination processes, and their performances are defined by their salt rejection and energy consumption not to mention their antifouling property. RO membranes are easy to be designed and operated as well as they can produce high quality clean water (Greenlee et al. 2009; Tarboush et al. 2008) by employing a high hydraulic pressure to force the water through the semi-permeable membrane (Liu et al. 2011). RO membranes with an active layer on the top are called thin film composite (TFC) (Fathizadeh et al. 2011). The standard material for this active layer is polyamide (Tiraferri et al. 2011), and it employs the diffusion mechanism to separate the water from the pollutants (Paul 2004).
The primary disadvantages of RO membranes are high energy consumption (Liu et al. 2011) and irreversible membrane fouling (Chung et al. 2012); in addition to that, the polyamide tends to degrade in the presence of the chemical oxidants that are used for mitigation of the microbial growth (Tiraferri et al. 2011). Consequently, many attempts have been proposed utilizing nanoparticles to functionalize the active layer to improve TFC membrane application. Modification methods include incorporation of nanomaterial into the active layer of TFC (Lee et al. 2011) to evolve new polyamide-nanoparticle (NP) membranes which are called thin film nanocomposite (TFN) membranes with increased fouling resistance, higher permeability, and improved salt rejection (Fathizadeh et al. 2011). Figure 6 shows the difference between TFC and TFN. The most prominent nanoparticles being researched for integration into the active layer are nano-zeolites that proved to maintain the solute rejection and resulted in thicker, more permeable, and hydrophilic negatively charged active layer (Jeong et al. 2007; Lind et al. 2009). Also, TiO2 increased the water flux and led to organic degradation and microbial inactivation upon ultraviolet (UV) irradiation due to its photocatalytic attributes (Chin et al. 2006). Finally, silver nanoparticle-TFN membranes exhibited an obvious antibiofouling influence on Pseudomonas (Lee et al. 2007), while unaligned SWCNTs were covalently bound to the TFC membrane surface and inactivated 60 % of E. coli bacteria attached to the membrane within 1 h of contact time resulting in moderate biological antifouling membrane (Tiraferri et al. 2011).
Comparing to conventional RO membrane, FO membrane is considered less prone to fouling (Ge et al. 2010; Holloway et al. 2007; Niksefat et al. 2014) and does not consume energy (Cornelissen et al. 2008) for it is exploiting the osmotic pressure gradient as the driving force for the separation process and draws water from a low osmotic pressure solution, referred to as “feed” to a high osmotic pressure one, often referred to as “draw solute” (Buonomenna 2013; Liu et al. 2011). However, the product of FO membranes (the diluted draw solution) usually requires a second separation step (Chung et al. 2012) to generate pure water either by applying RO or thermal treatment and both have high-cost and energy-intensive operations. To address this challenge, it is recommended to have a high osmolality draw solution that can be separated easily from water (Ge et al. 2010) as well as applying a low-cost separation technology. Recently, nanoparticles have been discovered as a new draw solution and used to develop a novel draw solution recovery system. For instance, hydrophilic coated magnetic nanoparticles have been explored as new, easily separable, and reusable draw solution with high osmotic pressure that improved FO membrane performance (Ge et al. 2010). Moreover, magnetic nanoparticles have been applied to recover draw solutes without any intensive energy input where their negatively charged surface facilitated the recovery process through coagulation (Liu et al. 2011).
In the light of FO process disadvantages, it is important to mention that the main obstacle of FO application is the accumulation of the rejected feed solutes in the support layer resulting in what is known as internal concentration polarization (ICP) (Loeb et al. 1997; Tang et al. 2010). This phenomenon causes an intense loss in the osmotic driving force (McCutcheon and Elimelech 2008), and since it occurs in the support layer, it cannot be removed by increasing the flow rate turbulence (Zhao et al. 2012a). With the intention to minimize the ICP problem, it was suggested that the fabrication of appropriate FO membranes with small structure parameter for the support layer had improved the membrane behavior (Liu et al. 2011). In recent times, developments of nanotechnology have led to fabrication of novel groups of FO membranes inspired by the thin film nanocomposite reverse osmosis (TFN-RO) membranes. The nanostructured FO membranes, synthesized with metal oxide nanoparticles or carbon nanotubes, demonstrated considerably enhanced membrane properties like selectivity, permeability, and stability in different separation processes (Amini et al. 2013). After all, nanotechnology has contributed in eco-sustainable membrane processes for wastewater treatment, producing pure drinking water without any wastes.
Disinfection and pathogen control
Disinfection process is applied to inactivate various types of microbial pathogens including viruses, bacteria, protozoa, and other microorganisms that often found in water from sewage discharges or runoff from animal feedlots into the water bodies. Although the current conventional disinfectants such as chlorine, chloramines, ozone, chlorine dioxide, and chlorine gas (Savage and Diallo 2005) can effectively control the microbial growth, they have short-lived reactivity and can be problematic due to formation of toxic disinfection by-products (DBPs) (Li et al. 2008b). These DBPs are formed by the reaction between the aforesaid conventional oxidizing disinfectants with various constituents (e.g., NOMs) in water (Hossain et al. 2014). More than 600 DBPs have been acknowledged all over the world (Richardson et al. 2007) and most of which are considered carcinogenic. This dilemma is aggravated when high dosages of the oxidizing disinfectant are required to kill highly resistant pathogens such as Cryptosporidium and Giardia (Li et al. 2008b). These limitations provoke an urgent need to balance the risks of microbial pathogens and formation of toxic DBPs. Therefore, it is important to provide an innovative alternative technique that can effectively prevent DBP formation and improve the reliability of disinfection by using harmless, non-corrosive, water-soluble disinfectants (Rutala et al. 2008).
The rapid development of nanotechnology has encouraged a significant concern in studying the antimicrobial characteristics of several nanomaterials (NMs) and applying them for water disinfection processes. These NMs have shown a promising approach to be utilized as alternatives for conventional disinfectants (Li et al. 2008b) as well as to be associated with other existing technologies to enhance the disinfection efficacy such as photo-excitation due to the ability of the NMs to be excited under solar light illumination (Hossain et al. 2014). Accordingly, many NPs have suggested to control the microbial growth and inactivate different types of microorganisms in water, such as metal and metal oxide nanoparticles (Dizaj et al. 2014; Vargas-Reus et al. 2012) (e.g., TiO2 (Dimitroula et al. 2012; Mayer et al. 2014), magnesium oxide (MgO) (Jin and He 2011), zinc oxide (ZnO) (Gordon et al. 2011), nanosilver (nAg) (Kaegi et al. 2011), nZVI (Crane and Scott 2012; Lee et al. 2008a, b)), carbon nanotubes (Ahmed et al. 2013; Vecitis et al. 2011), chitosan (Badawy et al. 2005; Chirkov 2002; Kong et al. 2010; Qi et al. 2004), and fullerene NPs (nC60) (Aquino et al. 2010; Dizaj et al. 2015; Lyon et al. 2008).
The abovementioned nanoparticles have shown good antimicrobial properties without strong oxidation, employing diverse mechanisms to disinfect water. Several antimicrobial mechanisms have been proposed for various nanoscale metal oxides, for instance, it was confirmed that the surface of zerovalent iron nanoparticles (ZVIn) corrode and create more metal oxides that could inactivate waterborne viruses by carrying out two critical mechanisms: irreversible adsorption and inactivation of viruses by direct contact (You et al. 2005). Another example on nanoscale metal oxides is ZnO that demonstrated as a strong antibacterial effect on different types of bacteria (Adams et al. 2006; Aruoja et al. 2009; Sawai and Yoshikawa 2004). The main antibacterial mechanism of ZnO is the photocatalytic generation of hydrogen peroxide (H2O2) from ZnO surface (Sawai and Yoshikawa 2004; Yamamoto 2001) followed by cell envelop penetration and accumulation of ZnO nanoparticles in membranes and cytoplasm of bacteria leading to bactericidal cell damage and inactivation or inhabitation of bacterial growth (Brayner et al. 2006; Huang et al. 2008; Jones et al. 2008). Additionally, it was verified that due to the photoreactivity and visible light response of TiO2, it can inactivate microorganisms under UV/solar irradiation by generating hydroxyl radical (OH•), superoxide radical (O2 •−), and hydrogen peroxide H2O2 as reactive oxygen species (ROS) (Cho et al. 2005; Li et al. 2008b). Besides, it was concluded that the photocatalytic inactivation of bacteria (Page et al. 2007; Pratap Reddy et al. 2007) and viruses (Kim et al. 2006) was improved by doping TiO2 with silver; thus, (Ag/TiO2) shows a great potential as a photocatalytic material. By the same token, the antimicrobial mechanism of the widely used silver nanoparticles stems from the release of silver ions (Ag+) which accounts for the biological response even at low concentration (Xiu et al. 2011, 2012). Silver ions inactivate the respiratory enzymes of bacteria by binding to thiol group in proteins (Liau et al. 1997) and result in production of ROS. In addition to that, Ag+ interacts with DNA preventing its replication and forming structural changes in the cell envelope (Matsumura et al. 2003; Qu et al. 2013a).
On the other hand, the cytotoxicity of carbon-based nanomaterials (CBNs) (e.g., CNTs, fullerene, etc.) to bacteria in aqueous solution is a complex function of solution chemistry, transport behavior, and physiochemical properties of the nanomaterials (Kang et al. 2009). The antibacterial activity of CNTs starts with an initial contact between the bacteria and CNTs followed either by physical perturbation of cell membrane or by disruption of particular microbial process through oxidizing of vital cellular structure/component (Vecitis et al. 2010) and both cases lead to bacterial cell death. One of the main factors governing the antibacterial activity of CNTs is their size (diameter) (Liu et al. 2009). Therefore, the small-diameter, short-length SWCNTs with surface groups of −OH and −COOH demonstrate the strongest antibacterial activity (Arias and Yang 2009; Kang et al. 2007; Yang et al. 2010a). Figure 7 shows the antibacterial effects of SWCNTs on E. coli bacteria. Another illustration for CNM antibacterial mechanism is fullerene NP (nC60) mechanism to kill bacteria which is mostly assigned to its ability to produce ROS resulting in various types of cell damage including DNA damage, lipid peroxidation, protein oxidation, as well as interruption of cellular respiration (Fang et al. 2007; Lyon and Alvarez 2008). Fullerene mechanism requires a direct contact between the nanoparticles and bacteria cells which makes it different from previously reported mechanisms of nanomaterial that involve ROS generation (metal oxides) or release of toxic elements (silver nanoparticles). Finally, chitosan, derived from shells of shrimp and other sea crustaceans (Shahidi and Synowiecki 1991), at its nanoscale has long been noted for its antimicrobial activity. The main proposed antimicrobial mechanism for chitosan is that the positively charged chitosan particles interact with negatively charged bacteria increasing the permeability of cell membranes and eventually leak the cell substances (Holappa et al. 2006; Qi et al. 2004). In short, nanomaterial had proven to be good disinfecting agents for water treatment systems by employing diverse antibacterial mechanisms (Fig. 8) as well as they successfully overcome the limitations that hindered the viability of conventional disinfection (Mahendra et al. 2014).
Photocatalysis
The main problems that are affecting the water treatment competence are removing of non-biodegradable organic pollutants which are resistant to conventional treatment methods, as well as killing waterborne pathogens without the formation of harmful DBPs from disinfection process. Addressing these problems calls for an imperative need to develop an innovative, low-cost, and eco-friendly technology that can destroy these pollutants with less energy consumption and less chemical utilization. Therefore, research activities have focused on advanced oxidation processes (AOPs) as alternative robust methods that are capable of oxidizing and mineralizing wide range of organic chemicals (Comninellis et al. 2008) due to their highly potent and strongly oxidizing radicals (Gaya and Abdullah 2008b).
Photocatalysis, a well-known AOP, has been established as an efficient method to enhance the biodegradability of persistent organic contaminants and to remove the current and emerging microbial pathogens. Photocatalytic oxidation comprises a class of reactions which use a catalyst activated by solar, chemical, or other forms of energy (Augugliaro et al. 2006; Bahnemann 2004; Kudo et al. 2003) and relies on generation of strong reactive radical species such as H2O2, O2 •–, O3 (Pera-Titus et al. 2004), and mostly hydroxyl radical (OH•) (Huang et al. 2000), which is a strong oxidizing agent that non-selectively destroys all organic molecules in water (Wang and Xu 2012).
The main source for the generation of (OH•) is the conventional oxidants H2O2 and O3 (Karci 2014). Different methods have been reported to photolyze these oxidants, facilitating compliance with the specific treatment requirements and improve the versatility of AOPs (Malato et al. 2009). Methods are based on UV (Goi and Trapido 2002) and combination of UV light and oxidants (H2O2, O2 •–, O3, etc.) (Karci 2014; Malato et al. 2009). In addition to those methods that involve catalysts, homogeneous photocatalysis method which is based on the addition of H2O2 to dissolved iron salts can be classified into two types of reaction: Fenton reaction that does not involve any light irradiation and photo-Fenton reaction that reacts up to a light wavelength of 600 nm (Chong et al. 2010). Moreover, heterogeneous photocatalysis methods use wide-band gap semiconductors in contact with water (e.g., TiO2 (Fujishima et al. 2008; Gaya and Abdullah 2008b; Wang and Jing 2014), tungsten trioxide (WO3) (Liu et al. 2013a; Zhao et al. 2012b), ZnO (Kaur and Singhal 2014; Yassıtepe et al. 2008), tin dioxide (SnO2) (Al-Hamdi et al. 2015; Jana et al. 2014), cadmium sulfide (CdS) (Chronopoulos et al. 2014; Upadhyay et al. 2012), etc.), and they are photoexcited by light in the presence of oxygen (Malato et al. 2013). Table 6 shows different methods that are used to produce hydroxyl radicals.
Both homogeneous (photo-Fenton) and heterogeneous photocatalysis methods are considered of great interests because they can either use UV light (Pera-Titus et al. 2004) or solar light (Malato et al. 2013; Maldonado et al. 2007) for irradiation. Although photo-Fenton photocatalysis has higher reactivity than heterogeneous photocatalysis, its operation is complex and expensive due to pH rectification that is required to control the formation of photoactive iron complexes (De Laat et al. 2004). Accordingly, heterogeneous photocatalysis proved to be a promising water treatment technology for elimination of persistent organic pollutants as well as for water sterilization.
Among the abovementioned semiconductors, TiO2 has drawn a special attention in the water treatment research including photodegradation of numerous organic pollutants, photoreduction of inorganic contaminants, and inactivation of microorganisms (Chong 2010; Kurniawan and Sillanpää 2011), due to its environmentally benign merits such as low toxicity, high photoconductivity, chemical stability, as well as its low cost and commercial availability (Choi et al. 2014; Fujishima et al. 2000; Xiao et al. 2015). The photocatalysis mechanism of (TiO2) that relies on the formation of active oxygen species such as hydroxyl radicals, superoxide, hydrogen peroxide, singlet oxygen, etc. may participate in organic pollutant photodegradation or disinfection process (Fujishima et al. 2008). The mechanism consists of several steps (Berger et al. 2006; Chong 2010; Fujishima et al. 2000; Fujishima et al. 2008; Gaya and Abdullah 2008b; Krishna et al. 2006; Mayer et al. 2014) starting with photoexcitation in order to induce series of reductive and oxidative reaction on the surface of (TiO2) photocatalyst through irradiation by an adequate wavelength (usually with photon energy (hv) greater than or equal to the band gap energy). Since the band gap of (TiO2) is about 3.0 eV, wavelengths shorter than ∼400 nm can excite the lone electron from the valance band to the empty conduction band in femtoseconds resulting in the generation of electron-hole pair. Super oxide radical anions (•O2 −) and hydroxyl radicals (OH•) are then generated through reaction between photogenerated electrons and molecular oxygen and between photogenerated holes and water, respectively. Hydroxyl radicals are considered the major species responsible for decomposition of organic pollutants (Zhang et al. 2009) into water and carbon dioxide. Figure 9 represents the mechanism steps of TiO2 photocatalysis.
However, several disadvantages of nanocrystalline TiO2 powders in water system have been identified, such as agglomeration, difficult recovery, and short activity which could restrain its application in wastewater treatment (Baolong et al. 2003; Xi and Geissen 2001). For the purpose of overcoming the mentioned drawbacks and developing highly active catalyst to be exploited for large scale applications, the morphological, crystallographic, and electronic properties of TiO2 material should be controlled through alternative synthesis procedures (Choi et al. 2010). The most common investigated methods to prepare TiO2 are sol–gel method (Caratto et al. 2012), which is used to fabricate highly pure with a relatively low temperature nanosized titanium dioxide and hydrothermal method (Jing et al. 2011), that works in synthesizing high crystalline titanium dioxide with controlled size and shape. Thereupon, three main approaches that are aimed to modify titanium dioxide (Xiao et al. 2015) have been highlighted in Table 7. Development of TiO2 composites codoped with two or more of nonmetals such as S, N, F, and C (Banerjee et al. 2014; Fagan et al. 2016; Likodimos et al. 2013) is considered one of the promising strategies that have been suggested to reduce the band gap and improve the visible light (VIS) responsive photocatalytic activity. For instance, N-F-codoped TiO2 under VIS has successfully been used for photocatalytic degradation of bisphenol A (BPA) due to its high surface area-to-volume ratio, enrichment of surface oxygen vacancies by F- and N-doping, improved surface acidity by F-doping, as well as enhancement of VIS absorption by N-doping (He et al. 2016). Moreover, carbon-doped TiO2 composites under VIS have been used for the degradation of some occurring algal toxins in water (e.g., cyanotoxins, microcystin-LR (MC-LR), and cylindrospermopsin (CYN)), and the resulting intermediate products from the toxins degradation process were attributed to a peroxide that was formed through the action of O2 •− (Fotiou et al. 2016). In short, photocatalytic process of nonmetal doped TiO2 has shown large potential as a renewable water treatment process and it is considered a more eco-friendly approach compared to the photocatalytic process of metal-doped TiO2, for the latter is vulnerable to photocorrosion and potential metal problems (Zhang et al. 2014).
Sensing and monitoring systems
A major challenge for environmental remediation management is monitoring the emission of toxic substance (i.e., organic and inorganic pollutants, pathogens, and hazardous atmospheric pollutants), coupled with accurately assessing the extent and composition of these contaminants. Therefore, various analytical techniques have been employed in environmental pollution detection and monitoring, for instance surface plasmon resonance (SPR) (Homola 2006; Salah et al. 2014; Shankaran et al. 2007), high-performance liquid chromatography (HPLC) (Shintani 2014), gas chromatography–mass spectrometry (GC-MS) (Tranchida et al. 2015), supercritical fluid chromatography (SFC) (Ishibashi et al. 2015), capillary electrophoresis (CE) (Sánchez-Hernández et al. 2014), flow injection analysis (FIA) (Gerez et al. 2014), etc. Nevertheless, these techniques are inappropriate for routine environmental detection because of their high cost and time consumption in addition to their complicated requirements (Su et al. 2012).
The growing advances in nanoscience and nanotechnology are having a remarkable influence on the field of environmental monitoring and sensing, where a large number of nanoparticles have been introduced for detection and remediation of wide range of contaminants (Andreescu et al. 2009; Theron et al. 2008, 2010) in both gaseous and aqueous mediums. Many investigations have been carried out to develop high selectivity and sensitivity nanosensors for monitoring different types of gases in the ambient air (Zhou et al. 2015) in order to prevent potential explosion or poisoning, particularly for odorless, colorless, and tasteless hazardous gases such as hydrogen (Baik et al. 2009; Lupan et al. 2008) and for poisonous and irritant gases such as nitrogen dioxide (NO2) (Beheshtian et al. 2012; Young et al. 2005). Similarly, the application of nanomaterial-based sensors is widely studied for water quality monitoring by detection of organism fecal pollution (Savichtcheva and Okabe 2006) such as fecal coliforms, total coliforms, E. coli, enterococci bacteriophages, and disease-causing viruses and parasites (Theron et al. 2010) and detection of different types of trace contaminants (such as pesticides, phenolic compounds, inorganic anions, heavy metals) (Govindhan et al. 2014).
As any other chemical sensors, nanoparticle-based sensors usually consist of two components: the receptor, which enhances the detection sensitivity, and the transducer, a chemical or physical sense component (nanomaterial), that works with electrochemical, thermal, optical, and other detection principles (Su et al. 2012). The operating mechanism involves a charge transfer that occurs between pollutant molecules and the receptors, resulting in an electrical and/or optical signal that is related to the molecule type and number (Di Francia et al. 2009). Not to mention that in the case of bio-nanosensors, recognitions agents (e.g., antibodies (Kalele et al. 2006; Volkert and Haes 2014), carbohydrates (Chen et al. 2011b; Haseley 2002), aptamers (Li et al. 2009; So et al. 2005), and antimicrobial peptidesis (AMPs) (Arcidiacono et al. 2008; Cui et al. 2012b)) are presented as a third components and specifically provide the selectivity by interacting with antigens or other epitopes on the pathogens surface (Vikesland and Wigginton 2010). Moreover, to obtain nanosensors with high sensitivity and fast response time, nanostructures such as nanorods, nanobelts, and nanowires were functionalized (Kanade et al. 2007). For instance, tungsten oxide nanowires (WO3-NWs) were functionalized with palladium for hydrogen gas detection (Chávez et al. 2013) and with copper oxide for high-performance hydrogen sulfide sensor (Park et al. 2014).
As a matter of fact, nanomaterial-based sensors have shown great potential in the chemical and biological detection researches due to their physical, chemical, optical, catalytic, magnetic, and electronic properties as well as their high selectivity and sensitivity (Qu et al. 2013a; Wang et al. 2010a). Some examples of widely used nanomaterials in sensors technology include quantum dots (QDs) which can be benefited from their fluorescence properties to detect heavy metals, toxic gases, cyanotoxins, and pathogens (Feng et al. 2014) (Hahn et al. 2005; Koneswaran and Narayanaswamy 2009; Li et al. 2008a; Ma et al. 2009; Wu et al. 2010). Metal nanoparticles such as silver and gold nanoparticles rely on the changes in their color for pollutant detection (McFarland and Van Duyne 2003; Saha et al. 2012). Furthermore, CNMs are facilitating the electron transfer between electrodes and electro-active species (Su et al. 2012), and they have been employed for monitoring of different pollutants and toxins. For instance, SWCNT and MWCNT were effectively used to develop electrochemical systems for monitoring of MC-LR in water below its WHO provisional concentration limit (Han et al. 2013; Wang et al. 2009). The specificity of MWCNT biosensor was improved by adding monoclonal antibodies specific to MC-LR in the incubation solutions, and the performance of MWCNT array biosensor was enhanced by electrochemical functionalization of MWCNT in alkaline solution to enrich its surface with oxygen containing functional groups that permit the immobilization of MC-LR onto MWCNT array electrodes (Han et al. 2013).
Conclusion
The exacerbated human activities are convulsing the ecosystem balance by feeding the environment with large amounts of anthropogenic hazardous toxicants that pollute soil, water, and atmosphere and consequently threaten human public health. As an attempt to adopt a compatible treatment technology for cleaning up all the wastes that are left behind the industrial revolution, this account simply compared the application of propitious nanotechnology to conventional technologies in environmental remediation. Moreover, this paper highlighted the hurdles that limit the application of nanomaterials and suppress the advantages of their unrivaled merits; such hurdles include conditions of surrounding environment (e.g., humidity, temperature, acidity, etc.), particle agglomeration, and separation difficulties. It has been shown that nanotechnology exhibits remarkable features for advanced, robust, and multifunctional treatment processes that can enhance pollution monitoring, treatment performance, as well as overcome all the aforementioned barriers. In brief, nanotechnology has the potential to improve the environmental remediation system by preventing the formation of secondary by-products, decomposing some of toxic pollutants by zero waste operations, and prohibiting further soil contamination by converting the pollutants from labile to non-labile phases. Finally, nanotechnology will pave the way for versatile and vibrant systems which involve the cutting edge techniques in sensing and monitoring of varieties of harmful chemicals and toxins in different environmental media.
References
Abanades JC, Alvarez D (2003) Conversion limits in the reaction of CO2 with lime. Energy Fuel 17:308–315
Abbasizadeh S, Keshtkar AR, Mousavian MA (2014) Sorption of heavy metal ions from aqueous solution by a novel cast PVA/TiO2 nanohybrid adsorbent functionalized with amine groups. J Ind Eng Chem 20:1656–1664. doi:10.1016/j.jiec.2013.08.013
Abdel Salam M, Burk RC (2008) Thermodynamics of pentachlorophenol adsorption from aqueous solutions by oxidized multi-walled carbon nanotubes. Appl Surf Sci 255:1975–1981. doi:10.1016/j.apsusc.2008.06.168
Abdel-Ghani NT, El-Chaghaby GA, Helal FS (2014) Individual and competitive adsorption of phenol and nickel onto multiwalled carbon nanotubes. J Adv Res. doi:10.1016/j.jare.2014.06.001
Adams LK, Lyon DY, Alvarez PJJ (2006) Comparative eco-toxicity of nanoscale TiO2, SiO2, and ZnO water suspensions. Water Res 40:3527–3532. doi:10.1016/j.watres.2006.08.004
Aguilar ZP (2013) Chapter 2—types of nanomaterials and corresponding methods of synthesis. In: Aguilar ZP (ed) Nanomaterials for medical applications. Elsevier, pp 33–82. doi:10.1016/B978-0-12-385089-8.00002-9
Ahmed F, Santos CM, Vergara RAMV, Tria MCR, Advincula R, Rodrigues DF (2011) Antimicrobial applications of electroactive PVK-SWNT nanocomposites. Environ Sci Technol 46:1804–1810. doi:10.1021/es202374e
Ahmed F, Santos CM, Mangadlao J, Advincula R, Rodrigues DF (2013) Antimicrobial PVK:SWNT nanocomposite coated membrane for water purification: performance and toxicity testing. Water Res 47:3966–3975. doi:10.1016/j.watres.2012.10.055
Ai L, Zhang C, Liao F, Wang Y, Li M, Meng L, Jiang J (2011) Removal of methylene blue from aqueous solution with magnetite loaded multi-wall carbon nanotube: kinetic, isotherm and mechanism analysis. J Hazard Mater 198:282–290. doi:10.1016/j.jhazmat.2011.10.041
Al-Hamdi AM, Sillanpää M, Dutta J (2015) Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation. J Alloys Compd 618:366–371. doi:10.1016/j.jallcom.2014.08.120
Amini M, Jahanshahi M, Rahimpour A (2013) Synthesis of novel thin film nanocomposite (TFN) forward osmosis membranes using functionalized multi-walled carbon nanotubes. J Membr Sci 435:233–241. doi:10.1016/j.memsci.2013.01.041
An B, Zhao D (2012) Immobilization of As(III) in soil and groundwater using a new class of polysaccharide stabilized Fe–Mn oxide nanoparticles. J Hazard Mater 211–212:332–341. doi:10.1016/j.jhazmat.2011.10.062
Andreescu S, Njagi J, Ispas C, Ravalli MT (2009) JEM spotlight: applications of advanced nanomaterials for environmental monitoring. J Environ Monit 11:27–40
Apul OG, Karanfil T (2015) Adsorption of synthetic organic contaminants by carbon nanotubes: a critical review. Water Res 68:34–55. doi:10.1016/j.watres.2014.09.032
Aquino A, Chan J, Giolma K, Loh M (2010) The effect of a fullerene water suspension on the growth, cell viability, and membrane integrity of Escherichia coli B23. J Exp Microbiol Immunol 14:13–20
Arahman N, Maruyama T, Sotani T, Matsuyama H (2009) Fouling reduction of a poly(ether sulfone) hollow-fiber membrane with a hydrophilic surfactant prepared via non-solvent-induced phase separation. J Appl Polym Sci 111:1653–1658. doi:10.1002/app.29149
Arcibar-Orozco JA, Rangel-Mendez JR, Bandosz TJ (2013) Reactive adsorption of SO2 on activated carbons with deposited iron nanoparticles. J Hazard Mater 246–247:300–309. doi:10.1016/j.jhazmat.2012.12.001
Arcidiacono S, Pivarnik P, Mello CM, Senecal A (2008) Cy5 labeled antimicrobial peptides for enhanced detection of Escherichia coli O157: H7. Biosens Bioelectron 23:1721–1727
Arias LR, Yang L (2009) Inactivation of bacterial pathogens by carbon nanotubes in suspensions. Langmuir 25:3003–3012. doi:10.1021/la802769m
Aruoja V, Dubourguier H-C, Kasemets K, Kahru A (2009) Toxicity of nanoparticles of CuO, ZnO and TiO2 to microalgae Pseudokirchneriella subcapitata. Sci Total Environ 407:1461–1468. doi:10.1016/j.scitotenv.2008.10.053
Auffan M et al (2008) Enhanced adsorption of arsenic onto maghemites nanoparticles: As(III) as a probe of the surface structure and heterogeneity. Langmuir 24:3215–3222. doi:10.1021/la702998x
Augugliaro V, Litter M, Palmisano L, Soria J (2006) The combination of heterogeneous photocatalysis with chemical and physical operations: a tool for improving the photoprocess performance. J Photochem Photobiol C: Photochem Rev 7:127–144
Badawy ME, Rabea EI, Rogge TM, Stevens CV, Steurbaut W, Höfte M, Smagghe G (2005) Fungicidal and insecticidal activity of O-acyl chitosan derivatives. Polym Bull 54:279–289
Bae T-H, Tak T-M (2005) Effect of TiO2 nanoparticles on fouling mitigation of ultrafiltration membranes for activated sludge filtration. J Membr Sci 249:1–8. doi:10.1016/j.memsci.2004.09.008
Bahnemann D (2004) Photocatalytic water treatment: solar energy applications. Sol Energy 77:445–459
Baik JM, Kim MH, Larson C, Yavuz CT, Stucky GD, Wodtke AM, Moskovits M (2009) Pd-sensitized single vanadium oxide nanowires: highly responsive hydrogen sensing based on the metal-insulator transition. Nano Lett 9:3980–3984. doi:10.1021/nl902020t
Balamurugan R, Sundarrajan S, Ramakrishna S (2011) Recent trends in nanofibrous membranes and their suitability for air and water filtrations. Membranes 1:232–248
Balta S, Sotto A, Luis P, Benea L, Van der Bruggen B, Kim J (2012) A new outlook on membrane enhancement with nanoparticles: the alternative of ZnO. J Membr Sci 389:155–161. doi:10.1016/j.memsci.2011.10.025
Baltrusaitis J, Jayaweera PM, Grassian VH (2011) Sulfur dioxide adsorption on TiO2 nanoparticles: influence of particle size, coadsorbates, sample pretreatment, and light on surface speciation and surface coverage. J Phys Chem C 115:492–500. doi:10.1021/jp108759b
Banerjee S, Pillai SC, Falaras P, O’Shea KE, Byrne JA, Dionysiou DD (2014) New insights into the mechanism of visible light photocatalysis. J Phys Chem Lett 5:2543–2554. doi:10.1021/jz501030x
Baolong Z, Baishun C, Keyu S, Shangjin H, Xiaodong L, Zongjie D, Kelian Y (2003) Preparation and characterization of nanocrystal grain TiO2 porous microspheres. Appl Catal B Environ 40:253–258. doi:10.1016/S0926-3373(02)00083-8
Bayen S, Wurl O, Karuppiah S, Sivasothi N, Lee HK, Obbard JP (2005) Persistent organic pollutants in mangrove food webs in Singapore. Chemosphere 61:303–313
Bazrafshan E, Mostafapour FK, Hosseini AR, Raksh Khorshid A, Mahvi AH (2012) Decolorisation of reactive red 120 dye by using single-walled carbon nanotubes in aqueous solutions. J Chem 2013:8. doi:10.1155/2013/938374
Beheshtian J, Baei MT, Bagheri Z, Peyghan AA (2012) AIN nanotube as a potential electronic sensor for nitrogen dioxide. Microelectron J 43:452–455. doi:10.1016/j.mejo.2012.04.002
Berger T, Diwald O, Knözinger E, Sterrer M, Yates JT Jr (2006) UV induced local heating effects in TiO2 nanocrystals. Phys Chem Chem Phys 8:1822–1826
Bernardo P, Drioli E, Golemme G (2009) Membrane gas separation: a review/state of the art. Ind Eng Chem Res 48:4638–4663
Bjørkøy A, Fiksdal L (2009) Characterization of biofouling on hollow fiber membranes using confocal laser scanning microscopy and image analysis. Desalination 245:474–484. doi:10.1016/j.desal.2009.02.011
Bolan N et al (2014) Remediation of heavy metal(loid)s contaminated soils—to mobilize or to immobilize? J Hazard Mater 266:141–166. doi:10.1016/j.jhazmat.2013.12.018
Bottino A, Capannelli G, D’Asti V, Piaggio P (2001) Preparation and properties of novel organic–inorganic porous membranes. Sep Purif Technol 22–23:269–275. doi:10.1016/S1383-5866(00)00127-1
Bottino A, Capannelli G, Comite A (2002) Preparation and characterization of novel porous PVDF-ZrO2 composite membranes. Desalination 146:35–40. doi:10.1016/S0011-9164(02)00469-1
Brame J, Li Q, Alvarez PJJ (2011) Nanotechnology-enabled water treatment and reuse: emerging opportunities and challenges for developing countries. Trends Food Sci Technol 22:618–624. doi:10.1016/j.tifs.2011.01.004
Brayner R, Ferrari-Iliou R, Brivois N, Djediat S, Benedetti MF, Fiévet F (2006) Toxicological impact studies based on Escherichia coli bacteria in ultrafine ZnO nanoparticles colloidal medium. Nano Lett 6:866–870. doi:10.1021/nl052326h
Buonomenna MG (2013) Membrane processes for a sustainable industrial growth. RSC Advances 3:5694–5740. doi:10.1039/C2RA22580H
Bystrzejewski M, Pyrzyńska K (2011) Kinetics of copper ions sorption onto activated carbon, carbon nanotubes and carbon-encapsulated magnetic nanoparticles. Colloids Surf A Physicochem Eng Asp 377:402–408. doi:10.1016/j.colsurfa.2011.01.041
Bystrzejewski M, Pyrzyńska K, Huczko A, Lange H (2009) Carbon-encapsulated magnetic nanoparticles as separable and mobile sorbents of heavy metal ions from aqueous solutions. Carbon 47:1201–1204. doi:10.1016/j.carbon.2009.01.007
Cai N, Larese-Casanova P (2014) Sorption of carbamazepine by commercial graphene oxides: a comparative study with granular activated carbon and multiwalled carbon nanotubes. J Colloid Interface Sci 426:152–161. doi:10.1016/j.jcis.2014.03.038
Cao X, Ma J, Shi X, Ren Z (2006) Effect of TiO2 nanoparticle size on the performance of PVDF membrane. Appl Surf Sci 253:2003–2010. doi:10.1016/j.apsusc.2006.03.090
Caratto V, Setti L, Campodonico S, Carnasciali M, Botter R, Ferretti M (2012) Synthesis and characterization of nitrogen-doped TiO2 nanoparticles prepared by sol–gel method. J Sol-Gel Sci Technol 63:16–22
Celebioglu A, Sen HS, Durgun E, Uyar T (2016) Molecular entrapment of volatile organic compounds (VOCs) by electrospun cyclodextrin nanofibers. Chemosphere 144:736–744. doi:10.1016/j.chemosphere.2015.09.029
Chang C-F, Chang C-Y, Hsu T-L (2011) Removal of fluoride from aqueous solution with the superparamagnetic zirconia material. Desalination 279:375–382. doi:10.1016/j.desal.2011.06.039
Chávez F et al (2013) Sensing performance of palladium-functionalized WO3 nanowires by a drop-casting method. Appl Surf Sci 275:28–35. doi:10.1016/j.apsusc.2013.01.145
Chen S-S, Hsu H-D, Li C-W (2004) A new method to produce nanoscale iron for nitrate removal. J Nanoparticle Res 6:639–647
Chen C, Hu J, Shao D, Li J, Wang X (2009a) Adsorption behavior of multiwall carbon nanotube/iron oxide magnetic composites for Ni(II) and Sr(II). J Hazard Mater 164:923–928. doi:10.1016/j.jhazmat.2008.08.089
Chen G-C et al (2009b) Adsorption of 2,4,6-trichlorophenol by multi-walled carbon nanotubes as affected by Cu(II). Water Res 43:2409–2418. doi:10.1016/j.watres.2009.03.002
Chen G-C, Shan X-Q, Pei Z-G, Wang H, Zheng L-R, Zhang J, Xie Y-N (2011a) Adsorption of diuron and dichlobenil on multiwalled carbon nanotubes as affected by lead. J Hazard Mater 188:156–163. doi:10.1016/j.jhazmat.2011.01.095
Chen Y et al (2011b) Electronic detection of lectins using carbohydrate-functionalized nanostructures: graphene versus carbon nanotubes. ACS Nano 6:760–770
Chen Z, Pierre D, He H, Tan S, Pham-Huy C, Hong H, Huang J (2011c) Adsorption behavior of epirubicin hydrochloride on carboxylated carbon nanotubes. Int J Pharm 405:153–161. doi:10.1016/j.ijpharm.2010.11.034
Cheung O, Bacsik Z, Liu Q, Mace A, Hedin N (2013) Adsorption kinetics for CO2 on highly selective zeolites NaKA and nano-NaKA. Appl Energy 112:1326–1336. doi:10.1016/j.apenergy.2013.01.017
Chin SS, Chiang K, Fane AG (2006) The stability of polymeric membranes in a TiO2 photocatalysis process. J Membr Sci 275:202–211. doi:10.1016/j.memsci.2005.09.033
Chirkov S (2002) The antiviral activity of chitosan (review). Appl Biochem Microbiol 38:1–8
Cho M, Chung H, Choi W, Yoon J (2005) Different inactivation behaviors of MS-2 phage and Escherichia coli in TiO2 photocatalytic disinfection. Appl Environ Microbiol 71:270–275
Cho H-H, Huang H, Schwab K (2011) Effects of solution chemistry on the adsorption of ibuprofen and triclosan onto carbon nanotubes. Langmuir 27:12960–12967. doi:10.1021/la202459g
Choi H, Stathatos E, Dionysiou DD (2006a) Sol–gel preparation of mesoporous photocatalytic TiO2 films and TiO2/Al2O3 composite membranes for environmental applications. Appl Catal B Environ 63:60–67. doi:10.1016/j.apcatb.2005.09.012
Choi J-H, Jegal J, Kim W-N (2006b) Fabrication and characterization of multi-walled carbon nanotubes/polymer blend membranes. J Membr Sci 284:406–415. doi:10.1016/j.memsci.2006.08.013
Choi H, Al-Abed SR, Dionysiou DD, Stathatos E, Lianos P (2010) Chapter 8 TiO2-based advanced oxidation nanotechnologies for water purification and reuse. In: Isabel CE, Andrea IS (eds) Sustainability science and engineering, vol 2. Elsevier, pp 229–254. doi:10.1016/S1871-2711(09)00208-6
Choi H, Zakersalehi A, Al-Abed SR, Han C, Dionysiou DD (2014) Chapter 8—nanostructured titanium oxide film- and membrane-based photocatalysis for water treatment. In: Savage ASSD (ed) Nanotechnology applications for clean water, 2nd edn. William Andrew Publishing, Oxford, pp 123–132. doi:10.1016/B978-1-4557-3116-9.00008-1
Chong MNJB, Chow CWK, Saint C (2010) Recent developments in photocatalytic water treatment technology: a review. Water Res 44:2997–3027. doi:10.1016/j.watres.2010.02.039
Chowdhury SR, Yanful EK (2013) Kinetics of cadmium(II) uptake by mixed maghemite-magnetite nanoparticles. J Environ Manag 129:642–651. doi:10.1016/j.jenvman.2013.08.028
Chronopoulos D, Karousis N, Zhao S, Wang Q, Shinohara H, Tagmatarchis N (2014) Photocatalytic application of nanosized CdS immobilized onto functionalized MWCNTs. Dalton Trans 43:7429–7434
Chrysochoou M, Johnston CP, Dahal G (2012) A comparative evaluation of hexavalent chromium treatment in contaminated soil by calcium polysulfide and green-tea nanoscale zero-valent iron. J Hazard Mater 201–202:33–42. doi:10.1016/j.jhazmat.2011.11.003
Chung T-S, Li X, Ong RC, Ge Q, Wang H, Han G (2012) Emerging forward osmosis (FO) technologies and challenges ahead for clean water and clean energy applications. Curr Opin Chem Eng 1:246–257
Ciston S, Lueptow RM, Gray KA (2009) Controlling biofilm growth using reactive ceramic ultrafiltration membranes. J Membr Sci 342:263–268. doi:10.1016/j.memsci.2009.06.049
Cloete TE (2010) Nanotechnology in water treatment applications. Horizon Scientific Press, New York
Comninellis C, Kapalka A, Malato S, Parsons SA, Poulios I, Mantzavinos D (2008) Advanced oxidation processes for water treatment: advances and trends for R&D. J Chem Technol Biotechnol 83:769–776
Cong Y, Zhang J, Chen F, Anpo M (2007) Synthesis and characterization of nitrogen-doped TiO2 nanophotocatalyst with high visible light activity. J Phys Chem C 111:6976–6982
Cornelissen E, Harmsen D, De Korte K, Ruiken C, Qin J-J, Oo H, Wessels L (2008) Membrane fouling and process performance of forward osmosis membranes on activated sludge. J Membr Sci 319:158–168
Crane RA, Scott TB (2012) Nanoscale zero-valent iron: future prospects for an emerging water treatment technology. J Hazard Mater 211:112–125. doi:10.1016/j.jhazmat.2011.11.073
Cui Y, Liu L, Li B, Zhou X, Xu N (2010) Fabrication of tunable core–shell structured TiO2 mesoporous microspheres using linear polymer polyethylene glycol as templates. J Phys Chem C 114:2434–2439
Cui Y, Kim SN, Naik RR, McAlpine MC (2012a) Biomimetic peptide nanosensors. Acc Chem Res 45:696–704
Cui H, Li Q, Gao S, Shang JK (2012b) Strong adsorption of arsenic species by amorphous zirconium oxide nanoparticles. J Ind Eng Chem 18:1418–1427. doi:10.1016/j.jiec.2012.01.045
Daly AaPZ (2007) An introduction to air pollution—definitions, classifications, and history. In: Zannetti P, Al-Ajmi D, Al-Rashied S (ed) Ambient air pollution. The Arab School for Science and Technology (ASST) (http://www.arabschool.org.sy) and The EnviroComp Institute (http://www.envirocomp.org/)
Daraei P, Madaeni SS, Ghaemi N, Khadivi MA, Astinchap B, Moradian R (2013) Enhancing antifouling capability of PES membrane via mixing with various types of polymer modified multi-walled carbon nanotube. J Membr Sci 444:184–191. doi:10.1016/j.memsci.2013.05.020
De Gusseme B et al (2011) Virus disinfection in water by biogenic silver immobilized in polyvinylidene fluoride membranes. Water Res 45:1856–1864. doi:10.1016/j.watres.2010.11.046
De Laat J, Le GT, Legube B (2004) A comparative study of the effects of chloride, sulfate and nitrate ions on the rates of decomposition of H2O2 and organic compounds by Fe (II)/H2O2 and Fe (III)/H2O2. Chemosphere 55:715–723
Deng J, Shao Y, Gao N, Deng Y, Tan C, Zhou S, Hu X (2012) Multiwalled carbon nanotubes as adsorbents for removal of herbicide diuron from aqueous solution. Chem Eng J 193–194:339–347. doi:10.1016/j.cej.2012.04.051
Di Francia G, Alfano B, La Ferrara V (2009) Conductometric gas nanosensors. J Sens. doi:10.1155/2009/659275
Dimitroula H, Daskalaki VM, Frontistis Z, Kondarides DI, Panagiotopoulou P, Xekoukoulotakis NP, Mantzavinos D (2012) Solar photocatalysis for the abatement of emerging micro-contaminants in wastewater: synthesis, characterization and testing of various TiO2 samples. Appl Catal B Environ 117:283–291. doi:10.1016/j.apcatb.2012.01.024
Dizaj SM, Lotfipour F, Barzegar-Jalali M, Zarrintan MH, Adibkia K (2014) Antimicrobial activity of the metals and metal oxide nanoparticles. Mater Sci Eng C 44:278–284. doi:10.1016/j.msec.2014.08.031
Dizaj SM, Mennati A, Jafari S, Khezri K, Adibkia K (2015) Antimicrobial activity of carbon-based nanoparticles. Adv Pharm Bull 5–19
Dong F, Zhao W, Wu Z (2008) Characterization and photocatalytic activities of C, N and S co-doped TiO2 with 1D nanostructure prepared by the nano-confinement effect. Nanotechnology 19:365607
Duncan TV (2011) Applications of nanotechnology in food packaging and food safety: barrier materials, antimicrobials and sensors. J Colloid Interface Sci 363:1–24
Ebert K, Fritsch D, Koll J, Tjahjawiguna C (2004) Influence of inorganic fillers on the compaction behaviour of porous polymer based membranes. J Membr Sci 233:71–78. doi:10.1016/j.memsci.2003.12.012
El-Temsah YS, Joner EJ (2013) Effects of nano-sized zero-valent iron (nZVI) on DDT degradation in soil and its toxicity to collembola and ostracods. Chemosphere 92:131–137. doi:10.1016/j.chemosphere.2013.02.039
Engates K, Shipley H (2011) Adsorption of Pb, Cd, Cu, Zn, and Ni to titanium dioxide nanoparticles: effect of particle size, solid concentration, and exhaustion. Environ Sci Pollut Res 18:386–395. doi:10.1007/s11356-010-0382-3
Fagan R, McCormack DE, Dionysiou DD, Pillai SC (2016) A review of solar and visible light active TiO2 photocatalysis for treating bacteria, cyanotoxins and contaminants of emerging concern. Mater Sci Semicond Process 42(Part1):2–14. doi:10.1016/j.mssp.2015.07.052
Fang J, Lyon DY, Wiesner MR, Dong J, Alvarez (2007) Effect of a fullerene water suspension on bacterial phospholipids and membrane phase behavior. Environ Sci Technol 41:2636–2642. doi:10.1021/es062181w
Fang Z, Qiu X, Chen J, Qiu X (2011a) Debromination of polybrominated diphenyl ethers by Ni/Fe bimetallic nanoparticles: influencing factors, kinetics, and mechanism. J Hazard Mater 185:958–969
Fang Z, Qiu X, Chen J, Qiu X (2011b) Degradation of the polybrominated diphenyl ethers by nanoscale zero-valent metallic particles prepared from steel pickling waste liquor. Desalination 267:34–41
Fathizadeh M, Aroujalian A, Raisi A (2011) Effect of added NaX nano-zeolite into polyamide as a top thin layer of membrane on water flux and salt rejection in a reverse osmosis process. J Membr Sci 375:88–95. doi:10.1016/j.memsci.2011.03.017
Feng L, Cao M, Ma X, Zhu Y, Hu C (2012) Superparamagnetic high-surface-area Fe3O4 nanoparticles as adsorbents for arsenic removal. J Hazard Mater 217–218:439–446. doi:10.1016/j.jhazmat.2012.03.073
Feng L, Zhu A, Wang H, Shi H (2014) A nanosensor based on quantum-dot haptens for rapid, on-site immunoassay of cyanotoxin in environmental water. Biosens Bioelectron 53:1–4. doi:10.1016/j.bios.2013.09.018
Fereidoun H, Nourddin MS, Rreza NA, Mohsen A, Ahmad R, Pouria H (2007) The effect of long-term exposure to particulate pollution on the lung function of Teheranian and Zanjanian students Pakistan. J Physiol 3:1–5
Fotiou T, Triantis TM, Kaloudis T, O’Shea KE, Dionysiou DD, Hiskia A (2016) Assessment of the roles of reactive oxygen species in the UV and visible light photocatalytic degradation of cyanotoxins and water taste and odor compounds using C–TiO2. Water Res 90:52–61. doi:10.1016/j.watres.2015.12.006
Fujishima A, Rao TN, Tryk DA (2000) Titanium dioxide photocatalysis. J Photochem Photobiol C: Photochem Rev 1:1–21. doi:10.1016/S1389-5567(00)00002-2
Fujishima A, Zhang X, Tryk DA (2008) TiO2 photocatalysis and related surface phenomena. Surf Sci Rep 63:515–582. doi:10.1016/j.surfrep.2008.10.001
Gao H, Zhao S, Cheng X, Wang X, Zheng L (2013) Removal of anionic azo dyes from aqueous solution using magnetic polymer multi-wall carbon nanotube nanocomposite as adsorbent. Chem Eng J 223:84–90. doi:10.1016/j.cej.2013.03.004
Gaya UI, Abdullah AH (2008a) Heterogeneous photocatalytic degradation of organic contaminants over titanium dioxide: a review of fundamentals, progress and problems. J Photochem Photobiol C: Photochem Rev 9:1–12
Gaya UI, Abdullah AH (2008b) Heterogeneous photocatalytic degradation of organic contaminants over titanium dioxide: a review of fundamentals, progress and problems. J Photochem Photobiol C: Photochem Rev 9:1–12. doi:10.1016/j.jphotochemrev.2007.12.003
Ge Q, Su J, Chung T-S, Amy G (2010) Hydrophilic superparamagnetic nanoparticles: synthesis, characterization, and performance in forward osmosis processes. Ind Eng Chem Res 50:382–388. doi:10.1021/ie101013w
Ge F, Li M-M, Ye H, Zhao B-X (2012) Effective removal of heavy metal ions Cd2+, Zn2+, Pb2+, Cu2+ from aqueous solution by polymer-modified magnetic nanoparticles. J Hazard Mater 211–212:366–372. doi:10.1016/j.jhazmat.2011.12.013
Gerez V, Rondano K, Pasquali C (2014) A simple manifold flow injection analysis for determining phosphorus in the presence of arsenate. J Water Chem Technol 36:19–24
Geyikçi F (2013) Adsorption of acid blue 161 (AB 161) dye from water by multi-walled carbon nanotubes. Fullerenes Nanotubes Carbon Nanostruct 21:579–593. doi:10.1080/1536383X.2011.643428
Ghaedi M, Kokhdan SN (2012) Oxidized multiwalled carbon nanotubes for the removal of methyl red (MR): kinetics and equilibrium study. Desalin Water Treat 49:317–325. doi:10.1080/19443994.2012.719355
Ghaedi M, Hassanzadeh A, Kokhdan SN (2011) Multiwalled carbon nanotubes as adsorbents for the kinetic and equilibrium study of the removal of alizarin red S and morin. J Chem Eng Data 56:2511–2520. doi:10.1021/je2000414
Ghenaatian HR, Baei MT, Hashemian S (2013) Zn12O12 nano-cage as a promising adsorbent for CS2 capture. Superlattice Microst 58:198–204. doi:10.1016/j.spmi.2013.03.006
Glover TG, Sabo D, Vaughan LA, Rossin JA, Zhang ZJ (2012) Adsorption of sulfur dioxide by CoFe2O4 spinel ferrite nanoparticles and corresponding changes in magnetism. Langmuir 28:5695–5702. doi:10.1021/la3003417
Goi A, Trapido M (2002) Hydrogen peroxide photolysis, Fenton reagent and photo-Fenton for the degradation of nitrophenols: a comparative study. Chemosphere 46:913–922
Gong J-L et al (2009) Removal of cationic dyes from aqueous solution using magnetic multi-wall carbon nanotube nanocomposite as adsorbent. J Hazard Mater 164:1517–1522. doi:10.1016/j.jhazmat.2008.09.072
Gopal R, Kaur S, Ma Z, Chan C, Ramakrishna S, Matsuura T (2006) Electrospun nanofibrous filtration membrane. J Membr Sci 281:581–586
Gopal R, Kaur S, Feng CY, Chan C, Ramakrishna S, Tabe S, Matsuura T (2007) Electrospun nanofibrous polysulfone membranes as pre-filters: particulate removal. J Membr Sci 289:210–219
Gordon T, Perlstein B, Houbara O, Felner I, Banin E, Margel S (2011) Synthesis and characterization of zinc/iron oxide composite nanoparticles and their antibacterial properties. Colloids Surf A Physicochem Eng Asp 374:1–8. doi:10.1016/j.colsurfa.2010.10.015
Govindhan M, Adhikari B-R, Chen A (2014) Nanomaterials-based electrochemical detection of chemical contaminants. RSC Adv 4:63741–63760. doi:10.1039/C4RA10399H
Goyal D, Durga G, Mishra A (2013) CHAPTER 7 Nanomaterials for water remediation. In: Green materials for sustainable water remediation and treatment. The Royal Society of Chemistry, pp 135–154. doi:10.1039/9781849735001-00135
Gray SR, Ritchie CB, Tran T, Bolto BA, Greenwood P, Busetti F, Allpike B (2008) Effect of membrane character and solution chemistry on microfiltration performance. Water Res 42:743–753. doi:10.1016/j.watres.2007.08.005
Greenlee LF, Lawler DF, Freeman BD, Marrot B, Moulin P (2009) Reverse osmosis desalination: water sources, technology, and today’s challenges. Water Res 43:2317–2348. doi:10.1016/j.watres.2009.03.010
Gupta VK, Agarwal S, Saleh TA (2011) Chromium removal by combining the magnetic properties of iron oxide with adsorption properties of carbon nanotubes. Water Res 45:2207–2212. doi:10.1016/j.watres.2011.01.012
Gupta VK, Kumar R, Nayak A, Saleh TA, Barakat MA (2013) Adsorptive removal of dyes from aqueous solution onto carbon nanotubes: a review. Adv Colloid Interf Sci 193–194:24–34. doi:10.1016/j.cis.2013.03.003
Hahn MA, Tabb JS, Krauss TD (2005) Detection of single bacterial pathogens with semiconductor quantum dots. Anal Chem 77:4861–4869
Han R, Zou W, Li H, Li Y, Shi J (2006) Copper(II) and lead(II) removal from aqueous solution in fixed-bed columns by manganese oxide coated zeolite. J Hazard Mater 137:934–942. doi:10.1016/j.jhazmat.2006.03.016
Han C et al (2013) A multiwalled‐carbon‐nanotube‐based biosensor for monitoring microcystin‐LR in sources of drinking water supplies. Adv Funct Mater 23:1807–1816
Hao Y-M, Man C, Hu Z-B (2010) Effective removal of Cu (II) ions from aqueous solution by amino-functionalized magnetic nanoparticles. J Hazard Mater 184:392–399. doi:10.1016/j.jhazmat.2010.08.048
Haseley SR (2002) Carbohydrate recognition: a nascent technology for the detection of bioanalytes. Anal Chim Acta 457:39–45
Hauptmann MLJ, Stewart PA, Hayes RB, Blair A (2004) Mortality from solid cancers among workers in formaldehyde industries. Am J Epidemiol 15:1117–1130
He F, Zhao D (2005) Preparation and characterization of a new class of starch-stabilized bimetallic nanoparticles for degradation of chlorinated hydrocarbons in water. Environ Sci Technol 39:3314–3320
He F, Zhao D (2007) Manipulating the size and dispersibility of zerovalent iron nanoparticles by use of carboxymethyl cellulose stabilizers. Environ Sci Technol 41:6216–6221
He M, Shi H, Zhao X, Yu Y, Qu B (2013) Immobilization of Pb and Cd in contaminated soil using nano-crystallite hydroxyapatite. Procedia Environ Sci 18:657–665. doi:10.1016/j.proenv.2013.04.090
He X, Aker WG, Pelaez M, Lin Y, Dionysiou DD, Hwang H-m (2016) Assessment of nitrogen–fluorine-codoped TiO2 under visible light for degradation of BPA: implication for field remediation. J Photochem Photobiol A Chem 314:81–92. doi:10.1016/j.jphotochem.2015.08.014
Herzberg M, Elimelech M (2007) Biofouling of reverse osmosis membranes: role of biofilm-enhanced osmotic pressure. J Membr Sci 295:11–20. doi:10.1016/j.memsci.2007.02.024
Holappa J et al (2006) Antimicrobial activity of chitosan N-betainates. Carbohydr Polym 65:114–118. doi:10.1016/j.carbpol.2005.11.041
Holloway RW, Childress AE, Dennett KE, Cath TY (2007) Forward osmosis for concentration of anaerobic digester centrate. Water Res 41:4005–4014. doi:10.1016/j.watres.2007.05.054
Homola J (2006) Surface plasmon resonance (SPR) sensors pp 45–67. Springer, London
Hossain F, Perales-Perez OJ, Hwang S, Román F (2014) Antimicrobial nanomaterials as water disinfectant: applications, limitations and future perspectives. Sci Total Environ 466–467:1047–1059. doi:10.1016/j.scitotenv.2013.08.009
Hotze M, Lowry G (2011) Nanotechnology for sustainable water treatment. In: Sustainable water. The Royal Society of Chemistry, pp 138–164. doi:10.1039/9781849732253-00138
Houde M et al (2008) Influence of lake characteristics on the biomagnification of persistent organic pollutants in lake trout food webs. Environ Toxicol Chem 27:2169–2178. doi:10.1897/08-071.1
Hu J, Shipley HJ (2012) Evaluation of desorption of Pb (II), Cu (II) and Zn (II) from titanium dioxide nanoparticles. Sci Total Environ 431:209–220. doi:10.1016/j.scitotenv.2012.05.039
Huang Z, Maness P-C, Blake DM, Wolfrum EJ, Smolinski SL, Jacoby WA (2000) Bactericidal mode of titanium dioxide photocatalysis. J Photochem Photobiol A Chem 130:163–170
Huang Z et al (2008) Toxicological effect of ZnO nanoparticles based on bacteria. Langmuir 24:4140–4144. doi:10.1021/la7035949
Huang J, Cao Y, Liu Z, Deng Z, Tang F, Wang W (2012) Efficient removal of heavy metal ions from water system by titanate nanoflowers. Chem Eng J 180:75–80. doi:10.1016/j.cej.2011.11.005
Hussain M, Ceccarelli R, Marchisio DL, Fino D, Russo N, Geobaldo F (2010) Synthesis, characterization, and photocatalytic application of novel TiO2 nanoparticles. Chem Eng J 157:45–51. doi:10.1016/j.cej.2009.10.043
Hussein AK (2015) Applications of nanotechnology in renewable energies—a comprehensive overview and understanding. Renew Sust Energ Rev 42:460–476. doi:10.1016/j.rser.2014.10.027
Hwang GB, Lee JE, Nho CW, Lee BU, Lee SJ, Jung JH, Bae G-N (2012) Short-term effect of humid airflow on antimicrobial air filters using Sophora flavescens nanoparticles. Sci Total Environ 421–422:273–279. doi:10.1016/j.scitotenv.2012.01.060
Iijima S (1991) Helical microtubules of graphitic carbon. Nature 354:56–58
Ishibashi M, Izumi Y, Sakai M, Ando T, Fukusaki E, Bamba T (2015) High-Throughput simultaneous analysis of pesticides by supercritical fluid chromatography coupled with high-resolution mass spectrometry. J Agric Food Chem 63:4457–4463. doi:10.1021/jf5056248
Jafari M, Aghamiri S (2011) Evaluation of carbon nanotubes as solid-phase extraction sorbent for the removal of cephalexin from aqueous solution. Desalin Water Treat 28:55–58
Jana S, Mitra BC, Bera P, Sikdar M, Mondal A (2014) Photocatalytic activity of galvanically synthesized nanostructure SnO2 thin films. J Alloys Compd 602:42–48. doi:10.1016/j.jallcom.2014.02.182
Jänchen J, Möhlmann DTF, Stach H (2007) Water and carbon dioxide sorption properties of natural zeolites and clay minerals at martian surface temperature and pressure conditions. In: Ruren Xu ZGJC, Wenfu Y (eds) Studies in surface science and catalysis, vol 170. Elsevier, New York, pp 2116–2121. doi:10.1016/S0167-2991(07)81108-6
Jeong B-H et al (2007) Interfacial polymerization of thin film nanocomposites: a new concept for reverse osmosis membranes. J Membr Sci 294:1–7. doi:10.1016/j.memsci.2007.02.025
Ji L, Chen W, Duan L, Zhu D (2009) Mechanisms for strong adsorption of tetracycline to carbon nanotubes: a comparative study using activated carbon and graphite as adsorbents. Environ Sci Technol 43:2322–2327. doi:10.1021/es803268b
Ji L, Chen W, Bi J, Zheng S, Xu Z, Zhu D, Alvarez PJ (2010) Adsorption of tetracycline on single-walled and multi-walled carbon nanotubes as affected by aqueous solution chemistry. Environ Toxicol Chem 29:2713–2719. doi:10.1002/etc.350
Jiang D, Zhang S, Zhao H (2007) Photocatalytic degradation characteristics of different organic compounds at TiO2 nanoporous film electrodes with mixed anatase/rutile phases. Environ Sci Technol 41:303–308
Jin T, He Y (2011) Antibacterial activities of magnesium oxide (MgO) nanoparticles against foodborne pathogens. J Nanoparticle Res 13:6877–6885. doi:10.1007/s11051-011-0595-5
Jin LM, Yu SL, Shi WX, Yi XS, Sun N, Ge YL, Ma C (2012) Synthesis of a novel composite nanofiltration membrane incorporated SiO2 nanoparticles for oily wastewater desalination. Polymer 53:5295–5303. doi:10.1016/j.polymer.2012.09.014
Jing Y, Li L, Zhang Q, Lu P, Liu P, Lü X (2011) Photocatalytic ozonation of dimethyl phthalate with TiO 2 prepared by a hydrothermal method. J Hazard Mater 189:40–47
Jones N, Ray B, Ranjit KT, Manna AC (2008) Antibacterial activity of ZnO nanoparticle suspensions on a broad spectrum of microorganisms. FEMS Microbiol Lett 279:71–76. doi:10.1111/j.1574-6968.2007.01012.x
Joo JB, Lee I, Dahl M, Moon GD, Zaera F, Yin Y (2013) Controllable synthesis of mesoporous TiO2 hollow shells: toward an efficient photocatalyst. Adv Funct Mater 23:4246–4254
Jung JHHG, Lee JE, Bae GN (2011) Preparation of airborne Ag/CNT hybrid nanoparticles using an aerosol process and their application to antimicrobial air filtration. Langmuir 27:10256–10264
Jung JH, Lee JE, Bae G-N (2013) Use of electrosprayed Sophora flavescens natural-product nanoparticles for antimicrobial air filtration. J Aerosol Sci 57:185–193. doi:10.1016/j.jaerosci.2012.09.004
Kaegi R, Voegelin A, Sinnet B, Zuleeg S, Hagendorfer H, Burkhardt M, Siegrist H (2011) Behavior of metallic silver nanoparticles in a pilot wastewater treatment plant. Environ Sci Technol 45:3902–3908. doi:10.1021/es1041892
Kalele SA, Kundu AA, Gosavi SW, Deobagkar DN, Deobagkar DD, Kulkarni SK (2006) Rapid detection of escherichia coli by using antibody‐conjugated silver nanoshells. Small 2:335–338
Kampa M, Castanas E (2008) Human health effects of air pollution. Environ Pollut 151:362–367. doi:10.1016/j.envpol.2007.06.012
Kanade K, Kale B, Baeg J-O, Lee SM, Lee CW, Moon S-J, Chang H (2007) Self-assembled aligned Cu doped ZnO nanoparticles for photocatalytic hydrogen production under visible light irradiation. Mater Chem Phys 102:98–104
Kang S, Pinault M, Pfefferle LD, Elimelech M (2007) Single-walled carbon nanotubes exhibit strong antimicrobial activity. Langmuir 23:8670–8673. doi:10.1021/la701067r
Kang S, Mauter MS, Elimelech M (2009) Microbial cytotoxicity of carbon-based nanomaterials: implications for river water and wastewater effluent. Environ Sci Technol 43:2648–2653. doi:10.1021/es8031506
Karci A (2014) Degradation of chlorophenols and alkylphenol ethoxylates, two representative textile chemicals, in water by advanced oxidation processes: the state of the art on transformation products and toxicity. Chemosphere 99:1–18. doi:10.1016/j.chemosphere.2013.10.034
Karn B, Kuiken T, Otto M (2009) Nanotechnology and in situ remediation: a review of the benefits and potential risks. Environ Health Perspect 117:1823–1831
Kaur J, Singhal S (2014) Facile synthesis of ZnO and transition metal doped ZnO nanoparticles for the photocatalytic degradation of Methyl Orange. Ceram Int 40:7417–7424
Kaur S, Kotaki M, Ma Z, Gopal R, Ramakrishna S, Sc N (2006) Oligosaccharide functionalized nanofibrous membrane. Int J Nanosci 05:1–11. doi:10.1142/S0219581X06004206
Kelly BC, Ikonomou MG, Blair JD, Morin AE, Gobas FAPC (2007) Food web-specific biomagnification of persistent organic pollutants. Science 317:236–239. doi:10.1126/science.1138275
Khajeh M, Laurent S, Dastafkan K (2013) Nanoadsorbents: classification, preparation, and applications (with emphasis on aqueous media). Chem Rev 113:7728–7768
Khan TA, Nazir M, Ali I, Kumar A (2013) Removal of Chromium(VI) from aqueous solution using guar gum–nano zinc oxide biocomposite adsorbent. Arab J Chem. doi:10.1016/j.arabjc.2013.08.019
Khodakovskaya M, Dervishi E, Mahmood M, Xu Y, Li Z, Watanabe F, Biris AS (2009) Carbon nanotubes are able to penetrate plant seed coat and dramatically affect seed germination and plant growth. ACS Nano 3:3221–3227
Kilianová M et al (2013) Remarkable efficiency of ultrafine superparamagnetic iron(III) oxide nanoparticles toward arsenate removal from aqueous environment. Chemosphere 93:2690–2697. doi:10.1016/j.chemosphere.2013.08.071
Kim SH, Kwak S-Y, Sohn B-H, Park TH (2003) Design of TiO2 nanoparticle self-assembled aromatic polyamide thin-film-composite (TFC) membrane as an approach to solve biofouling problem. J Membr Sci 211:157–165. doi:10.1016/S0376-7388(02)00418-0
Kim S, Hwang S-J, Choi W (2005) Visible light active platinum-ion-doped TiO2 photocatalyst. J Phys Chem B 109:24260–24267
Kim J, Cho I, Kim I, Kim C, Heo NH, Suh S (2006) Manufacturing of anti-viral inorganic materials from colloidal silver and titanium oxide. Rev Roum Chim 51:1121
Kiparissides C, Kammona O (2015) Nanotechnology advances in diagnostics, drug delivery, and regenerative medicine. The nano-micro interface: bridging the micro and nano worlds 8:311–340. books.google.com
Kočí K, Krejčíková S, Šolcová O, Obalová L (2012) Photocatalytic decomposition of N2O on Ag-TiO2. Catal Today 191:134–137. doi:10.1016/j.cattod.2012.01.021
Komvokis VG, Marti M, Delimitis A, Vasalos IA, Triantafyllidis KS (2011) Catalytic decomposition of N2O over highly active supported Ru nanoparticles (≤3 nm) prepared by chemical reduction with ethylene glycol. Appl Catal B Environ 103:62–71. doi:10.1016/j.apcatb.2011.01.009
Koneswaran M, Narayanaswamy R (2009) l-Cysteine-capped ZnS quantum dots based fluorescence sensor for Cu2+ ion. Sensors Actuators B Chem 139:104–109. doi:10.1016/j.snb.2008.09.028
Kong M, Chen XG, Xing K, Park HJ (2010) Antimicrobial properties of chitosan and mode of action: a state of the art review. Int J Food Microbiol 144:51–63. doi:10.1016/j.ijfoodmicro.2010.09.012
Kosa SA, Al-Zhrani G, Abdel Salam M (2012) Removal of heavy metals from aqueous solutions by multi-walled carbon nanotubes modified with 8-hydroxyquinoline. Chem Eng J 181–182:159–168. doi:10.1016/j.cej.2011.11.044
Koutsopoulos S, Johannessen T, Eriksen KM, Fehrmann R (2006) Titania-supported Pt and Pt–Pd nanoparticle catalysts for the oxidation of sulfur dioxide. J Catal 238:206–213
Koziol K, Vilatela J, Moisala A, Motta M, Cunniff P, Sennett M, Windle A (2007) High-performance carbon nanotube fiber. Science 318:1892–1895. doi:10.1126/science.1147635
Krishna V, Noguchi N, Koopman B, Moudgil B (2006) Enhancement of titanium dioxide photocatalysis by water-soluble fullerenes. J Colloid Interface Sci 304:166–171. doi:10.1016/j.jcis.2006.08.041
Kudo T, Nakamura Y, Ruike A (2003) Development of rectangular column structured titanium oxide photocatalysts anchored on silica sheets by a wet process. Res Chem Intermed 29:631–639
Kumar B, Mukherjee D, Kumar S, Mishra M, Prakash D, Singh S, Sharma C (2011) Bioaccumulation of heavy metals in muscle tissue of fishes from selected aquaculture ponds in east Kolkata wetlands. Ann Biol Res 2:125–134
Kumpiene J, Lagerkvist A, Maurice C (2008) Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments—a review. Waste Manag 28:215–225. doi:10.1016/j.wasman.2006.12.012
Kuo C-Y, Wu C-H, Wu J-Y (2008) Adsorption of direct dyes from aqueous solutions by carbon nanotubes: determination of equilibrium, kinetics and thermodynamics parameters. J Colloid Interface Sci 327:308–315. doi:10.1016/j.jcis.2008.08.038
Kurniawan TASM, Sillanpää M (2011) Nanoadsorbents for remediation of aquatic environment: local and practical solutions for global water pollution problems. Crit Rev Environ Sci Technol 42:1233–1295
Lam CWJJ, McCluskey R, Hunter RL (2004) Pulmonary toxicity of single-wall carbon nanotubes in mice 7 and 90 days after intratracheal instillation. Toxicol Sci 77:126–134
Lee N, Amy G, Croué J-P, Buisson H (2004) Identification and understanding of fouling in low-pressure membrane (MF/UF) filtration by natural organic matter (NOM). Water Res 38:4511–4523. doi:10.1016/j.watres.2004.08.013
Lee SY, Kim HJ, Patel R, Im SJ, Kim JH, Min BR (2007) Silver nanoparticles immobilized on thin film composite polyamide membrane: characterization, nanofiltration, antifouling properties. Polym Adv Technol 18:562–568. doi:10.1002/pat.918
Lee BUYS, Ji JH, Bae GN (2008a) Inactivation of S. epidermidis, B. subtilis, and E. coli bacteria bioaerosols deposited on a filter utilizing airborne silver nanoparticles. J Microbiol Biotechnol 18:176–182
Lee C, Kim JY, Lee WI, Nelson KL, Yoon J, Sedlak DL (2008b) Bactericidal effect of zero-valent iron nanoparticles on Escherichia coli. Environ Sci Technol 42:4927–4933. doi:10.1021/es800408u
Lee BUYS, Jung JH, Bae GN (2010a) Effect of relative humidity and variation of particle number size distribution on the inactivation effectiveness of airborne silver nanoparticles against bacteria bioaerosols deposited on a filter. J Aerosol Sci 41:447–456
Lee KJ, Shiratori N, Lee GH, Miyawaki J, Mochida I, Yoon S-H, Jang J (2010b) Activated carbon nanofiber produced from electrospun polyacrylonitrile nanofiber as a highly efficient formaldehyde adsorbent. Carbon 48:4248–4255. doi:10.1016/j.carbon.2010.07.034
Lee KP, Arnot TC, Mattia D (2011) A review of reverse osmosis membrane materials for desalination—development to date and future potential. J Membr Sci 370:1–22
Li D, Xia Y (2004) Electrospinning of nanofibers: reinventing the wheel? Adv Mater 16:1151–1170. doi:10.1002/adma.200400719
Li Y-H et al (2003a) Competitive adsorption of Pb2+, Cu2+ and Cd2+ ions from aqueous solutions by multiwalled carbon nanotubes. Carbon 41:2787–2792. doi:10.1016/S0008-6223(03)00392-0
Li Y-H, Wang S, Luan Z, Ding J, Xu C, Wu D (2003b) Adsorption of cadmium(II) from aqueous solution by surface oxidized carbon nanotubes. Carbon 41:1057–1062. doi:10.1016/S0008-6223(02)00440-2
Li H, Zhang Y, Wang X, Gao Z (2008a) A luminescent nanosensor for Hg (II) based on functionalized CdSe/ZnS quantum dots. Microchim Acta 160:119–123
Li Q, Mahendra S, Lyon DY, Brunet L, Liga MV, Li D, Alvarez PJJ (2008b) Antimicrobial nanomaterials for water disinfection and microbial control: potential applications and implications. Water Res 42:4591–4602. doi:10.1016/j.watres.2008.08.015
Li T, Shi L, Wang E, Dong S (2009) Multifunctional G‐quadruplex aptamers and their application to protein detection. Chem Eur J 15:1036–1042
Li J-h, Hong R-y, Luo G-h, Zheng Y, Li H-z, Wei D-g (2010) An easy approach to encapsulating Fe3O4 nanoparticles in multiwalled carbon nanotubes. New Carbon Mater 25:192–198. doi:10.1016/S1872-5805(09)60026-3
Li X et al (2013) Efficient adsorption of gold ions from aqueous systems with thioamide-group chelating nanofiber membranes. Chem Eng J 229:420–428. doi:10.1016/j.cej.2013.06.022
Li H, Zhang D, Han X, Xing B (2014a) Adsorption of antibiotic ciprofloxacin on carbon nanotubes: pH dependence and thermodynamics. Chemosphere 95:150–155
Li X et al (2014b) Self-assembly of TiO2 nanoparticles around the pores of PES ultrafiltration membrane for mitigating organic fouling. J Membr Sci 467:226–235. doi:10.1016/j.memsci.2014.05.036
Liang Q, Zhao D (2014) Immobilization of arsenate in a sandy loam soil using starch-stabilized magnetite nanoparticles. J Hazard Mater 271:16–23. doi:10.1016/j.jhazmat.2014.01.055
Liau SY, Read DC, Pugh WJ, Furr JR, Russell AD (1997) Interaction of silver nitrate with readily identifiable groups: relationship to the antibacterial action of silver ions. Lett Appl Microbiol 25:279–283. doi:10.1046/j.1472-765X.1997.00219.x
Likodimos V et al (2013) Anion-doped TiO2 nanocatalysts for water purification under visible light. Ind Eng Chem Res 52:13957–13964. doi:10.1021/ie3034575
Lin D, Xing B (2008) Adsorption of phenolic compounds by carbon nanotubes: role of aromaticity and substitution of hydroxyl groups. Environ Sci Technol 42:7254–7259. doi:10.1021/es801297u
Lin Y-H, Tseng T-K, Chu H (2014) Photo-catalytic degradation of dimethyl disulfide on S and metal-ions co-doped TiO2 under visible-light irradiation. Appl Catal A Gen 469:221–228. doi:10.1016/j.apcata.2013.10.006
Lind ML, Ghosh AK, Jawor A, Huang X, Hou W, Yang Y, Hoek EMV (2009) Influence of zeolite crystal size on zeolite-polyamide thin film nanocomposite membranes. Langmuir 25:10139–10145. doi:10.1021/la900938x
Lithoxoos GP, Labropoulos A, Peristeras LD, Kanellopoulos N, Samios J, Economou IG (2010) Adsorption of N2, CH4, CO and CO2 gases in single walled carbon nanotubes: a combined experimental and Monte Carlo molecular simulation study. J Supercrit Fluids 55:510–523. doi:10.1016/j.supflu.2010.09.017
Liu R, Zhao D (2007a) In situ immobilization of Cu(II) in soils using a new class of iron phosphate nanoparticles. Chemosphere 68:1867–1876. doi:10.1016/j.chemosphere.2007.03.010
Liu R, Zhao D (2007b) Reducing leachability and bioaccessibility of lead in soils using a new class of stabilized iron phosphate nanoparticles. Water Res 41:2491–2502. doi:10.1016/j.watres.2007.03.026
Liu R, Zhao D (2013) Synthesis and characterization of a new class of stabilized apatite nanoparticles and applying the particles to in situ Pb immobilization in a fire-range soil. Chemosphere 91:594–601. doi:10.1016/j.chemosphere.2012.12.034
Liu J, Rinzler AG, Dai HJ, Hafner JH, Bradley RK, Boul PJ, Lu A (1998) Fullerene pipes. Science 280:1253–1256
Liu X, Su DS, Schlögl R (2008) Oxidative dehydrogenation of 1-butene to butadiene over carbon nanotube catalysts. Carbon 46:547–549. doi:10.1016/j.carbon.2007.12.014
Liu S et al (2009) Sharper and faster “Nano darts” kill more bacteria: a study of antibacterial activity of individually dispersed pristine single-walled carbon nanotube. ACS Nano 3:3891–3902. doi:10.1021/nn901252r
Liu Z, Bai H, Lee J, Sun DD (2011) A low-energy forward osmosis process to produce drinking water. Energy Environ Sci 4:2582–2585
Liu G et al (2013a) Enhancement of visible-light-driven O-2 evolution from water oxidation on WO3 treated with hydrogen. J Catal 307:148–152. doi:10.1016/j.jcat.2013.06.024
Liu W, Wang T, Borthwick AGL, Wang Y, Yin X, Li X, Ni J (2013b) Adsorption of Pb2+, Cd2+, Cu2+ and Cr3+ onto titanate nanotubes: competition and effect of inorganic ions. Sci Total Environ 456–457:171–180. doi:10.1016/j.scitotenv.2013.03.082
Liu Y, Wang Z, Wang W, Huang W (2014) Engineering highly active TiO2 photocatalysts via the surface-phase junction strategy employing a titanate nanotube precursor. J Catal 310:16–23. doi:10.1016/j.jcat.2013.03.024
Loeb S, Titelman L, Korngold E, Freiman J (1997) Effect of porous support fabric on osmosis through a Loeb-Sourirajan type asymmetric membrane. J Membr Sci 129:243–249
Loos M (2015) Chapter 1—nanoscience and nanotechnology. In: Loos M (ed) Carbon nanotube reinforced composites. William Andrew Publishing, Oxford, pp 1–36. doi:10.1016/B978-1-4557-3195-4.00001-1
Lu C, Chiu H (2006) Adsorption of zinc(II) from water with purified carbon nanotubes. Chem Eng Sci 61:1138–1145. doi:10.1016/j.ces.2005.08.007
Lu C, Liu C (2006) Removal of nickel(II) from aqueous solution by carbon nanotubes. J Chem Technol Biotechnol 81:1932–1940. doi:10.1002/jctb.1626
Lu C, Chiu H, Liu C (2006) Removal of zinc(II) from aqueous solution by purified carbon nanotubes: kinetics and equilibrium studies. Ind Eng Chem Res 45:2850–2855. doi:10.1021/ie051206h
Lu SS, Chen L, Dong YH, Chen YX (2011) Adsorption of Eu(III) on iron oxide/multiwalled carbon nanotube magnetic composites. J Radioanal Nucl Chem 288:587–593
Lunge S, Singh S, Sinha A (2014) Magnetic iron oxide (Fe3O4) nanoparticles from tea waste for arsenic removal. J Magn Magn Mater 356:21–31. doi:10.1016/j.jmmm.2013.12.008
Luo C, Wei R, Guo D, Zhang S, Yan S (2013a) Adsorption behavior of MnO2 functionalized multi-walled carbon nanotubes for the removal of cadmium from aqueous solutions. Chem Eng J 225:406–415. doi:10.1016/j.cej.2013.03.128
Luo X, Wang C, Wang L, Deng F, Luo S, Tu X, Au C (2013b) Nanocomposites of graphene oxide-hydrated zirconium oxide for simultaneous removal of As(III) and As(V) from water. Chem Eng J 220:98–106. doi:10.1016/j.cej.2013.01.017
Lupan O, Chai G, Chow L (2008) Novel hydrogen gas sensor based on single ZnO nanorod. Microelectron Eng 85:2220–2225. doi:10.1016/j.mee.2008.06.021
Lv X, Xu J, Jiang G, Xu X (2011) Removal of chromium(VI) from wastewater by nanoscale zero-valent iron particles supported on multiwalled carbon nanotubes. Chemosphere 85:1204–1209. doi:10.1016/j.chemosphere.2011.09.005
Lyon DY, Alvarez PJJ (2008) Fullerene water suspension (nC60) exerts antibacterial effects via ROS-independent protein oxidation. Environ Sci Technol 42:8127–8132. doi:10.1021/es801869m
Lyon DY, Brunet L, Hinkal GW, Wiesner MR, Alvarez PJ (2008) Antibacterial activity of fullerene water suspensions (nC60) is not due to ROS-mediated damage. Nano Lett 8:1539–1543
Ma QY, Traina SJ, Logan TJ, Ryan JA (1993) In situ Pb immobilization by apatite. Environ Sci Technol 27:1803
Ma Z, Kotaki M, Ramakrishna S (2005) Electrospun cellulose nanofiber as affinity membrane. J Membr Sci 265:115–123. doi:10.1016/j.memsci.2005.04.044
Ma Q, Cui H, Su X (2009) Highly sensitive gaseous formaldehyde sensor with CdTe quantum dots multilayer films. Biosens Bioelectron 25:839–844. doi:10.1016/j.bios.2009.08.038
Machado FM, Bergmann CP, Fernandes THM, Lima EC, Royer B, Calvete T, Fagan SB (2011) Adsorption of Reactive Red M-2BE dye from water solutions by multi-walled carbon nanotubes and activated carbon. J Hazard Mater 192:1122–1131. doi:10.1016/j.jhazmat.2011.06.020
Machado FM et al (2012) Adsorption of reactive blue 4 dye from water solutions by carbon nanotubes: experiment and theory. Phys Chem Chem Phys 14:11139–11153. doi:10.1039/C2CP41475A
Madrakian T, Afkhami A, Ahmadi M, Bagheri H (2011) Removal of some cationic dyes from aqueous solutions using magnetic-modified multi-walled carbon nanotubes. J Hazard Mater 196:109–114. doi:10.1016/j.jhazmat.2011.08.078
Madrakian T, Afkhami A, Ahmadi M (2013) Simple in situ functionalizing magnetite nanoparticles by reactive blue-19 and their application to the effective removal of Pb2+ ions from water samples. Chemosphere 90:542–547. doi:10.1016/j.chemosphere.2012.08.025
Maggini L et al (2013) Magnetic poly(vinylpyridine)-coated carbon nanotubes: an efficient supramolecular tool for wastewater purification. ChemSusChem 6:367–373. doi:10.1002/cssc.201200413
Mahapatra A, Mishra BG, Hota G (2013) Electrospun Fe2O3–Al2O3 nanocomposite fibers as efficient adsorbent for removal of heavy metal ions from aqueous solution. J Hazard Mater 258–259:116–123. doi:10.1016/j.jhazmat.2013.04.045
Mahendra S, Li Q, Lyon DY, Brunet L, Alvarez PJJ (2014) Chapter 20—nanotechnology-enabled water disinfection and microbial control: merits and limitations. In: Street A, Sustich R, Duncan J, Savage N (eds) Nanotechnology applications for clean water, 2nd edn. William Andrew Publishing, Oxford, pp 319–327. doi:10.1016/B978-1-4557-3116-9.00020-2
Malato S, Fernandez-Ibanez P, Maldonado MI, Blanco J, Gernjak W (2009) Decontamination and disinfection of water by solar photocatalysis: recent overview and trends. Catal Today 147:1–59. doi:10.1016/j.cattod.2009.06.018
Malato S, Fernández-Ibáñez P, Maldonado MI, Oller I (2013) Chapter 15—solar photocatalytic processes: water decontamination and disinfection. In: Suib SL (ed) New and future developments in catalysis. Elsevier, Amsterdam, pp 371–393. doi:10.1016/B978-0-444-53872-7.00017-0
Maldonado M, Passarinho P, Oller I, Gernjak W, Fernández P, Blanco J, Malato S (2007) Photocatalytic degradation of EU priority substances: a comparison between TiO 2 and Fenton plus photo-Fenton in a solar pilot plant. J Photochem Photobiol A Chem 185:354–363
Mansoori GA, Soelaiman TF (2005) Nanotechnology—an introduction for the standards community. J ASTM Int 2:1–21
Matsumura Y, Yoshikata K, Kunisaki S-i, Tsuchido T (2003) Mode of bactericidal action of silver zeolite and its comparison with that of silver nitrate. Appl Environ Microbiol 69:4278–4281
Mauter MS, Wang Y, Okemgbo KC, Osuji CO, Giannelis EP, Elimelech M (2011) Antifouling ultrafiltration membranes via post-fabrication grafting of biocidal nanomaterials. ACS Appl Mater Interfaces 3:2861–2868. doi:10.1021/am200522v
Maximous N, Nakhla G, Wan W, Wong K (2010a) Performance of a novel ZrO2/PES membrane for wastewater filtration. J Membr Sci 352:222–230. doi:10.1016/j.memsci.2010.02.021
Maximous N, Nakhla G, Wong K, Wan W (2010b) Optimization of Al2O3/PES membranes for wastewater filtration. Sep Purif Technol 73:294–301. doi:10.1016/j.seppur.2010.04.016
Mayer BK, Daugherty E, Abbaszadegan M (2014) Disinfection byproduct formation resulting from settled, filtered, and finished water treated by titanium dioxide photocatalysis. Chemosphere 117:72–78. doi:10.1016/j.chemosphere.2014.05.073
McCutcheon JR, Elimelech M (2008) Influence of membrane support layer hydrophobicity on water flux in osmotically driven membrane processes. J Membr Sci 318:458–466
McFarland AD, Van Duyne RP (2003) Single silver nanoparticles as real-time optical sensors with zeptomole sensitivity. Nano Lett 3:1057–1062
Meng F, Chae S-R, Drews A, Kraume M, Shin H-S, Yang F (2009) Recent advances in membrane bioreactors (MBRs): membrane fouling and membrane material. Water Res 43:1489–1512. doi:10.1016/j.watres.2008.12.044
Merajin MT, Sharifnia S, Hosseini SN, Yazdanpour N (2013) Photocatalytic conversion of greenhouse gases (CO2 and CH4) to high value products using TiO2 nanoparticles supported on stainless steel webnet. J Taiwan Inst Chem Eng 44:239–246. doi:10.1016/j.jtice.2012.11.007
Metz B, Davidson OR, Bosch PR, Dave R, Meyer LA (eds) (2007) The fourth assessment report of the Intergovernmental Panel on Climate Change. Cambridge University Press, United Kingdom and New York, NY, USA
Miyawaki J, Lee G-H, Yeh J, Shiratori N, Shimohara T, Mochida I, Yoon S-H (2012) Development of carbon-supported hybrid catalyst for clean removal of formaldehyde indoors. Catal Today 185:278–283. doi:10.1016/j.cattod.2011.09.036
Monárrez-Cordero B, Amézaga-Madrid P, Antúnez-Flores W, Leyva-Porras C, Pizá-Ruiz P, Miki-Yoshida M (2014) Highly efficient removal of arsenic metal ions with high superficial area hollow magnetite nanoparticles synthetized by AACVD method. J Alloys Compd 586(Supplement 1):S520–S525. doi:10.1016/j.jallcom.2012.12.073
Moon GD, Joo JB, Dahl M, Jung H, Yin Y (2014) Nitridation and layered assembly of hollow TiO2 shells for electrochemical energy storage. Adv Funct Mater 24:848–856
Moradi O (2013) Adsorption behavior of basic red 46 by single-walled carbon nanotubes surfaces. Fullerenes, Nanotubes, Carbon Nanostruct 21:286–301
Mr A, Dimitroulopouloub C (2009) Personal exposure of children to air pollution. Atmos Environ 43:128–141
Mubarak NM, Alicia RF, Abdullah EC, Sahu JN, Haslija ABA, Tan J (2013) Statistical optimization and kinetic studies on removal of Zn2+ using functionalized carbon nanotubes and magnetic biochar. J Environ Chem Eng 1:486–495. doi:10.1016/j.jece.2013.06.011
Müller B, Zumbuehl A, Walter MA, Pfohl T, Cattin PC, Huwyler J, Hieber SE (2015) Translational medicine: nanoscience and nanotechnology to improve patient care. The nano-micro interface: bridging the micro and nano worlds 289–310. books.google.com
Nassar NN (2010) Rapid removal and recovery of Pb(II) from wastewater by magnetic nanoadsorbents. J Hazard Mater 184:538–546. doi:10.1016/j.jhazmat.2010.08.069
Natural Resources Conservation Service N (2000) Heavy metal soil contamination. Soil Quality Institute, United States Department of Agriculture. www.nrcs.usda.gov
Nguyen NH, Bai H (2015) Effect of washing pH on the properties of titanate nanotubes and its activity for photocatalytic oxidation of NO and NO2. Appl Surf Sci 355:672–680. doi:10.1016/j.apsusc.2015.07.118
Niksefat N, Jahanshahi M, Rahimpour A (2014) The effect of SiO2 nanoparticles on morphology and performance of thin film composite membranes for forward osmosis application. Desalination 343:140–146. doi:10.1016/j.desal.2014.03.031
NSTC/NNI/NSET (2003) National nanotechnology initiative: research and development supporting the next industrial revolution. www.nano.gov
Nuasaen S, Opaprakasit P, Tangboriboonrat P (2014) Hollow latex particles functionalized with chitosan for the removal of formaldehyde from indoor air. Carbohydr Polym 101:179–187. doi:10.1016/j.carbpol.2013.09.059
Obalová L, Reli M, Lang J, Matějka V, Kukutschová J, Lacný Z, Kočí K (2013) Photocatalytic decomposition of nitrous oxide using TiO2 and Ag-TiO2 nanocomposite thin films. Catal Today 209:170–175. doi:10.1016/j.cattod.2012.11.012
Ohama Y, Van Gemert D (2011) Application of titanium dioxide photocatalysis to construction materials: state-of-the-art report of the RILEM Technical Committee 194-TDP vol 5. Springer Science & Business Media
Pacholczyk A et al (2011) Phenol adsorption on closed carbon nanotubes. J Colloid Interface Sci 361:288–292. doi:10.1016/j.jcis.2011.05.032
Page K, Palgrave RG, Parkin IP, Wilson M, Savin SLP, Chadwick AV (2007) Titania and silver-titania composite films on glass-potent antimicrobial coatings. J Mater Chem 17:95–104. doi:10.1039/B611740F
Pan B, Xing B (2008) Adsorption mechanisms of organic chemicals on carbon nanotubes. Environ Sci Technol 42:9005–9013. doi:10.1021/es801777n
Pan B, Lin D, Mashayekhi H, Xing B (2008) Adsorption and hysteresis of bisphenol A and 17α-ethinyl estradiol on carbon nanomaterials. Environ Sci Technol 42:5480–5485. doi:10.1021/es8001184
Pan L, Zou J-J, Wang S, Huang Z-F, Yu A, Wang L, Zhang X (2013) Quantum dot self-decorated TiO2 nanosheets. Chem Commun 49:6593–6595
Pan L, Wang S, Zou J-J, Huang Z-F, Wang L, Zhang X (2014) Ti3+-defected and V-doped TiO2 quantum dots loaded on MCM-41. Chem Commun 50:988–990. doi:10.1039/c3cc47752e
Pang R, Li X, Li J, Lu Z, Sun X, Wang L (2014) Preparation and characterization of ZrO2/PES hybrid ultrafiltration membrane with uniform ZrO2 nanoparticles. Desalination 332:60–66. doi:10.1016/j.desal.2013.10.024
Park JH, Bolan N, Megharaj M, Naidu R (2011) Comparative value of phosphate sources on the immobilization of lead, and leaching of lead and phosphorus in lead contaminated soils. Sci Total Environ 409:853–860
Park S, Park S, Jung J, Hong T, Lee S, Kim HW, Lee C (2014) H2S gas sensing properties of CuO-functionalized WO3 nanowires. Ceram Int 40:11051–11056. doi:10.1016/j.ceramint.2014.03.120
Paul D (2004) Reformulation of the solution-diffusion theory of reverse osmosis. J Membr Sci 241:371–386
Pendergast MM, Hoek EM (2011) A review of water treatment membrane nanotechnologies. Energ Environ Sci 4:1946–1971
Pendergast MTM, Nygaard JM, Ghosh AK, Hoek EMV (2010) Using nanocomposite materials technology to understand and control reverse osmosis membrane compaction. Desalination 261:255–263. doi:10.1016/j.desal.2010.06.008
Peng X, Li Y, Luan Z, Di Z, Wang H, Tian B, Jia Z (2003) Adsorption of 1,2-dichlorobenzene from water to carbon nanotubes. Chem Phys Lett 376:154–158. doi:10.1016/S0009-2614(03)00960-6
Peng X, Luan Z, Di Z, Zhang Z, Zhu C (2005) Carbon nanotubes-iron oxides magnetic composites as adsorbent for removal of Pb(II) and Cu(II) from water. Carbon 43:880–883. doi:10.1016/j.carbon.2004.11.009
Peng H, Feng S, Zhang X, Li Y, Zhang X (2012a) Adsorption of norfloxacin onto titanium oxide: effect of drug carrier and dissolved humic acid. Sci Total Environ 438:66–71. doi:10.1016/j.scitotenv.2012.08.045
Peng H, Pan B, Wu M, Liu R, Zhang D, Wu D, Xing B (2012b) Adsorption of ofloxacin on carbon nanotubes: solubility, pH and cosolvent effects. J Hazard Mater 211–212:342–348. doi:10.1016/j.jhazmat.2011.12.063
Pera-Titus M, García-Molina V, Baños MA, Giménez J, Esplugas S (2004) Degradation of chlorophenols by means of advanced oxidation processes: a general review. Appl Catal B Environ 47:219–256
Perez-Aguilar NV, Diaz-Flores PE, Rangel-Mendez JR (2011) The adsorption kinetics of cadmium by three different types of carbon nanotubes. J Colloid Interface Sci 364:279–287. doi:10.1016/j.jcis.2011.08.024
Pibiri MCGA, Vahekeni N, Roulet CA (2006) Indoor air purification and ventilation systems sanitation with essential oils. Int J Aromather 16:149–153
Poursaberi T, Hassanisadi M, Torkestani K, Zare M (2012) Development of zirconium (IV)-metalloporphyrin grafted Fe3O4 nanoparticles for efficient fluoride removal. Chem Eng J 189–190:117–125. doi:10.1016/j.cej.2012.02.039
Pratap Reddy M, Venugopal A, Subrahmanyam M (2007) Hydroxyapatite-supported Ag–TiO2 as Escherichia coli disinfection photocatalyst. Water Res 41:379–386. doi:10.1016/j.watres.2006.09.018
Pu Y-C, Ling Y, Chang K-D, Liu C-M, Zhang JZ, Hsu Y-J, Li Y (2014) Surface passivation of TiO2 nanowires using a facile precursor-treatment approach for photoelectrochemical water oxidation. J Phys Chem C 118:15086–15094
Pyankov OVAI, Huang R, Mullins BJ (2008) Removal of biological aerosols by oil coated filters. Clean Soil Air Water 36:609–614
Pyrzyńska K, Bystrzejewski M (2010) Comparative study of heavy metal ions sorption onto activated carbon, carbon nanotubes, and carbon-encapsulated magnetic nanoparticles. Colloids Surf A Physicochem Eng Asp 362:102–109. doi:10.1016/j.colsurfa.2010.03.047
Qi L, Xu Z, Jiang X, Hu C, Zou X (2004) Preparation and antibacterial activity of chitosan nanoparticles. Carbohydr Res 339:2693–2700. doi:10.1016/j.carres.2004.09.007
Qu S, Huang F, Yu S, Chen G, Kong J (2008) Magnetic removal of dyes from aqueous solution using multi-walled carbon nanotubes filled with Fe2O3 particles. J Hazard Mater 160:643–647. doi:10.1016/j.jhazmat.2008.03.037
Qu X, Alvarez PJJ, Li Q (2013a) Applications of nanotechnology in water and wastewater treatment. Water Res 47:3931–3946. doi:10.1016/j.watres.2012.09.058
Qu X, Brame J, Li Q, Alvarez PJJ (2013b) Nanotechnology for a safe and sustainable water supply: enabling integrated water treatment and reuse. Acc Chem Res 46:834–843. doi:10.1021/ar300029v
Rafiq Z, Nazir R, Durre S, Shah MR, Ali S (2014) Utilization of magnesium and zinc oxide nano-adsorbents as potential materials for treatment of copper electroplating industry wastewater. J Environ Chem Eng 2:642–651. doi:10.1016/j.jece.2013.11.004
Rahimpour A (2011) UV photo-grafting of hydrophilic monomers onto the surface of nano-porous PES membranes for improving surface properties. Desalination 265:93–101. doi:10.1016/j.desal.2010.07.037
Rahimpour A, Madaeni SS (2007) Polyethersulfone (PES)/cellulose acetate phthalate (CAP) blend ultrafiltration membranes: preparation, morphology, performance and antifouling properties. J Membr Sci 305:299–312. doi:10.1016/j.memsci.2007.08.030
Rahimpour A, Madaeni SS, Taheri AH, Mansourpanah Y (2008) Coupling TiO2 nanoparticles with UV irradiation for modification of polyethersulfone ultrafiltration membranes. J Membr Sci 313:158–169. doi:10.1016/j.memsci.2007.12.075
Ramakrishna S, Fujihara K, Teo W-E, Yong T, Ma Z, Ramaseshan R (2006) Electrospun nanofibers: solving global issues. Mater Today 9:40–50. doi:10.1016/S1369-7021(06)71389-X
Ramsden J (2009) Essentials of nanotechnology. BookBoon. books.google.com
Rao GP, Lu C, Su F (2007) Sorption of divalent metal ions from aqueous solution by carbon nanotubes: a review. Sep Purif Technol 58:224–231. doi:10.1016/j.seppur.2006.12.006
Raymundo-Piñero E, Azaïs P, Cacciaguerra T, Cazorla-Amorós D, Linares-Solano A, Béguin F (2005) KOH and NaOH activation mechanisms of multiwalled carbon nanotubes with different structural organisation. Carbon 43:786–795. doi:10.1016/j.carbon.2004.11.005
Razmjou A, Mansouri J, Chen V (2011a) The effects of mechanical and chemical modification of TiO2 nanoparticles on the surface chemistry, structure and fouling performance of PES ultrafiltration membranes. J Membr Sci 378:73–84. doi:10.1016/j.memsci.2010.10.019
Razmjou A, Mansouri J, Chen V, Lim M, Amal R (2011b) Titania nanocomposite polyethersulfone ultrafiltration membranes fabricated using a low temperature hydrothermal coating process. J Membr Sci 380:98–113. doi:10.1016/j.memsci.2011.06.035
Razmjou A, Resosudarmo A, Holmes RL, Li H, Mansouri J, Chen V (2012) The effect of modified TiO2 nanoparticles on the polyethersulfone ultrafiltration hollow fiber membranes. Desalination 287:271–280. doi:10.1016/j.desal.2011.11.025
Recillas S, García A, González E, Casals E, Puntes V, Sánchez A, Font X (2011) Use of CeO2, TiO2 and Fe3O4 nanoparticles for the removal of lead from water: toxicity of nanoparticles and derived compounds. Desalination 277:213–220. doi:10.1016/j.desal.2011.04.036
Ren X, Chen C, Nagatsu M, Wang X (2011) Carbon nanotubes as adsorbents in environmental pollution management: a review. Chem Eng J 170:395–410. doi:10.1016/j.cej.2010.08.045
Reyhanitabar LA, Khataee A, Oustan S (2012) Application of stabilized Fe0 nanoparticles for remediation of Cr (VI)-spiked soil. Eur J Soil Sci 63:724–732
Richardson SD, Plewa MJ, Wagner ED, Schoeny R, DeMarini DM (2007) Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: a review and roadmap for research. Mutat Res Rev Mutat Res 636:178–242
Robinson BH, Bañuelos G, Conesa HM, Evangelou MWH, Schulin R (2009) The phytomanagement of trace elements in soil. Crit Rev Plant Sci 28:240–266
Rodriguez JA, Liu P, Pérez M, Liu G, Hrbek J (2010) Destruction of SO2 on Au and Cu nanoparticles dispersed on MgO(100) and CeO2(111). J Phys Chem A 114:3802–3810. doi:10.1021/jp905761s
Roy P, Berger S, Schmuki P (2011) TiO2 nanotubes: synthesis and applications. Angew Chem Int Ed 50:2904–2939
Rutala WA, Weber DJ, Control CfD (2008) Guideline for disinfection and sterilization in healthcare facilities, 2008. Centers for Disease Control (US). http://www.cdc.gov/hicpac/pdf/guidelines/Disinfection_Nov_2008.pdf
Saha K, Agasti SS, Kim C, Li X, Rotello VM (2012) Gold nanoparticles in chemical and biological sensing. Chem Rev 112:2739–2779. doi:10.1021/cr2001178
Salah NH, Jenkins D, Handy R (2014) Graphene and its influence in the improvement of surface plasmon resonance (SPR) based sensors: a review. ijirae.com
Salam MA (2013) Coating carbon nanotubes with crystalline manganese dioxide nanoparticles and their application for lead ions removal from model and real water. Colloids Surf A Physicochem Eng Asp 419:69–79. doi:10.1016/j.colsurfa.2012.11.064
Salam MA, Makki MSI, Abdelaal MYA (2011) Preparation and characterization of multi-walled carbon nanotubes/chitosan nanocomposite and its application for the removal of heavy metals from aqueous solution. J Alloys Compd 509:2582–2587. doi:10.1016/j.jallcom.2010.11.094
Saleh TA, Gupta VK (2012) Photo-catalyzed degradation of hazardous dye methyl orange by use of a composite catalyst consisting of multi-walled carbon nanotubes and titanium dioxide. J Colloid Interface Sci 371:101–106. doi:10.1016/j.jcis.2011.12.038
Saleh TA, Shuaib TD, Danmaliki GI, Al-Daous MA (2015) Carbon-based nanomaterials for desulfurization: classification, preparation, and evaluation. Applying nanotechnology to the desulfurization process in petroleum engineering, pp 154. books.google.com
Sánchez-Hernández L, Hernández-Domínguez D, Bernal J, Neusüß C, Martín MT, Bernal JL (2014) Capillary electrophoresis–mass spectrometry as a new approach to analyze neonicotinoid insecticides. J Chromatogr A 1359:317–324
Sathish M, Viswanath R, Gopinath CS (2009) N, S-Co-doped TiO2 nanophotocatalyst: synthesis, electronic structure and photocatalysis. J Nanosci Nanotechnol 9:423–432
Savage N, Diallo MS (2005) Nanomaterials and water purification: opportunities and challenges. J Nanoparticle Res 7:331–342
Savichtcheva O, Okabe S (2006) Alternative indicators of fecal pollution: relations with pathogens and conventional indicators, current methodologies for direct pathogen monitoring and future application perspectives. Water Res 40:2463–2476
Sawada I, Fachrul R, Ito T, Ohmukai Y, Maruyama T, Matsuyama H (2012) Development of a hydrophilic polymer membrane containing silver nanoparticles with both organic antifouling and antibacterial properties. J Membr Sci 387–388:1–6. doi:10.1016/j.memsci.2011.06.020
Sawai J, Yoshikawa T (2004) Quantitative evaluation of antifungal activity of metallic oxide powders (MgO, CaO and ZnO) by an indirect conductimetric assay. J Appl Microbiol 96:803–809. doi:10.1111/j.1365-2672.2004.02234.x
Sawant SY, Somani RS, Bajaj HC, Sharma SS (2012) A dechlorination pathway for synthesis of horn shaped carbon nanotubes and its adsorption properties for CO2, CH4, CO and N2. J Hazard Mater 227–228:317–326. doi:10.1016/j.jhazmat.2012.05.062
Scanlon DO et al (2013) Band alignment of rutile and anatase TiO2. Nat Mater 12:798–801
Serrano E, Rus G, García-Martínez J (2009) Nanotechnology for sustainable energy. Renew Sust Energ Rev 13:2373–2384. doi:10.1016/j.rser.2009.06.003
Shahidi F, Synowiecki J (1991) Isolation and characterization of nutrients and value-added products from snow crab (Chionoecetes opilio) and shrimp (Pandalus borealis) processing discards. J Agric Food Chem 39:1527–1532
Shankaran DR, Gobi KV, Miura N (2007) Recent advancements in surface plasmon resonance immunosensors for detection of small molecules of biomedical, food and environmental interest. Sensors Actuators B Chem 121:158–177
Shanthilal J, Bhattacharya S (2014) Nanoparticles and nanotechnology in food. In: Conventional and advanced food processing technologies. Wiley, pp 567–94. doi:10.1002/9781118406281.ch23
Sheela T, Nayaka YA (2012) Kinetics and thermodynamics of cadmium and lead ions adsorption on NiO nanoparticles. Chem Eng J 191:123–131. doi:10.1016/j.cej.2012.02.080
Shen J-n, Ruan H-m, Wu L-g, Gao C-j (2011) Preparation and characterization of PES–SiO2 organic–inorganic composite ultrafiltration membrane for raw water pretreatment. Chem Eng J 168:1272–1278. doi:10.1016/j.cej.2011.02.039
Sheng G, Li J, Shao D, Hu J, Chen C, Chen Y, Wang X (2010a) Adsorption of copper(II) on multiwalled carbon nanotubes in the absence and presence of humic or fulvic acids. J Hazard Mater 178:333–340. doi:10.1016/j.jhazmat.2010.01.084
Sheng GD, Shao DD, Ren XM, Wang XQ, Li JX, Chen YX, Wang XK (2010b) Kinetics and thermodynamics of adsorption of ionizable aromatic compounds from aqueous solutions by as-prepared and oxidized multiwalled carbon nanotubes. J Hazard Mater 178:505–516. doi:10.1016/j.jhazmat.2010.01.110
Shintani H (2014) Toxic compounds analysis with high performance liquid chromatography detected by electro chemical detector (ECD). Int J Clin Pharmacol Toxicol 3:121–127
Shon HK, Vigneswaran S, Kandasamy J, Cho J (2007) Characteristics of effluent organic matter in wastewater. In: Water and wastewater treatment technologies. EOLSS and UNESCO
Singh SP, Ma LQ, Harris WG (2001) Heavy metal interactions with phosphatic clay: sorption and desorption behaviour. J Environ Qual 30:1961
Singh M, Thanh DN, Ulbrich P, Strnadová N, Štěpánek F (2010) Synthesis, characterization and study of arsenate adsorption from aqueous solution by α- and δ-phase manganese dioxide nanoadsorbents. J Solid State Chem 183:2979–2986. doi:10.1016/j.jssc.2010.09.023
Singh J, Mukherjee A, Sengupta SK, Im J, Peterson GW, Whitten JE (2012) Sulfur dioxide and nitrogen dioxide adsorption on zinc oxide and zirconium hydroxide nanoparticles and the effect on photoluminescence. Appl Surf Sci 258:5778–5785. doi:10.1016/j.apsusc.2012.02.093
Slomberg DL, Schoenfisch MH (2012) Silica nanoparticle phytotoxicity to Arabidopsis thaliana. Environ Sci Technol 46:10247–10254
Smical A-I, Hotea V, Oros V, Juhasz J, Pop E (2008) Studies on transfer and bioaccumulation of heavy metals from soil into lettuce. Environ Eng Manag J 7:609–615
So H-M et al (2005) Single-walled carbon nanotube biosensors using aptamers as molecular recognition elements. J Am Chem Soc 127:11906–11907
Solomon SJ, Schade G, Kuttippurath J, Ladstätter-Weissenmayer A, Burrows J (2008) VOC concentrations in an indoor workplace environment of a university building. Indoor Built Environ 17:260–268
Song K, Kim W, Suh C-Y, Shin D, Ko K-S, Ha K (2013) Magnetic iron oxide nanoparticles prepared by electrical wire explosion for arsenic removal. Powder Technol 246:572–574. doi:10.1016/j.powtec.2013.06.023
Srisitthiratkul C, Pongsorrarith V, Intasanta N (2011) The potential use of nanosilver-decorated titanium dioxide nanofibers for toxin decomposition with antimicrobial and self-cleaning properties. Appl Surf Sci 257:8850–8856. doi:10.1016/j.apsusc.2011.04.083
Stafiej A, Pyrzynska K (2007) Adsorption of heavy metal ions with carbon nanotubes. Sep Purif Technol 58:49–52. doi:10.1016/j.seppur.2007.07.008
Stark PCBH, Ryan LM, Milton DK, Gold DR (2003) Fungal levels in the home and lower respiratory tract illnesses in the first year of life. Am J Respir Crit Care Med 7:168–232
Su F, Lu C, Cnen W, Bai H, Hwang JF (2009) Capture of CO2 from flue gas via multiwalled carbon nanotubes. Sci Total Environ 407:3017–3023. doi:10.1016/j.scitotenv.2009.01.007
Su F, Lu C, Hu S (2010) Adsorption of benzene, toluene, ethylbenzene and p-xylene by NaOCl-oxidized carbon nanotubes. Colloids Surf A Physicochem Eng Asp 353:83–91. doi:10.1016/j.colsurfa.2009.10.025
Su S, Wu W, Gao J, Lu J, Fan C (2012) Nanomaterials-based sensors for applications in environmental monitoring. J Mater Chem 22:18101–18110
Su Y, Cui H, Li Q, Gao S, Shang JK (2013) Strong adsorption of phosphate by amorphous zirconium oxide nanoparticles. Water Res 47:5018–5026. doi:10.1016/j.watres.2013.05.044
Sun M, Su Y, Mu C, Jiang Z (2009) Improved antifouling property of PES ultrafiltration membranes using additive of silica−PVP nanocomposite. Ind Eng Chem Res 49:790–796. doi:10.1021/ie900560e
Sun K, Zhang Z, Gao B, Wang Z, Xu D, Jin J, Liu X (2012a) Adsorption of diuron, fluridone and norflurazon on single-walled and multi-walled carbon nanotubes. Sci Total Environ 439:1–7. doi:10.1016/j.scitotenv.2012.08.022
Sun W, Li Q, Gao S, Shang JK (2012b) Exceptional arsenic adsorption performance of hydrous cerium oxide nanoparticles: part B. Integration with silica monoliths and dynamic treatment. Chem Eng J 185–186:136–143. doi:10.1016/j.cej.2012.01.060
Suri RP, Thornton HM, Muruganandham M (2012) Disinfection of water using Pt-and Ag-doped TiO2 photocatalysts. Environ Technol 33:1651–1659
Tan KA, Morad N, Teng TT, Norli I, Panneerselvam P (2012) Removal of cationic dye by magnetic nanoparticle (Fe3O4) impregnated onto activated maize cob powder and kinetic study of dye waste adsorption. APCBEE Procedia 1:83–89. doi:10.1016/j.apcbee.2012.03.015
Tang CY, She Q, Lay WC, Wang R, Fane AG (2010) Coupled effects of internal concentration polarization and fouling on flux behavior of forward osmosis membranes during humic acid filtration. J Membr Sci 354:123–133
Tang W-W et al (2012) Simultaneous adsorption of atrazine and Cu (II) from wastewater by magnetic multi-walled carbon nanotube. Chem Eng J 211–212:470–478. doi:10.1016/j.cej.2012.09.102
Tarboush BJA, Rana D, Matsuura T, Arafat HA, Narbaitz RM (2008) Preparation of thin-film-composite polyamide membranes for desalination using novel hydrophilic surface modifying macromolecules. J Membr Sci 325:166–175. doi:10.1016/j.memsci.2008.07.037
Tasis D, Tagmatarchis N, Bianco A, Prato M (2006) Chemistry of carbon nanotubes. Chem Rev 106:1105–1136. doi:10.1021/cr050569o
Theron J, Walker J, Cloete T (2008) Nanotechnology and water treatment: applications and emerging opportunities. Crit Rev Microbiol 34:43–69
Theron J, Eugene Cloete T, de Kwaadsteniet M (2010) Current molecular and emerging nanobiotechnology approaches for the detection of microbial pathogens. Crit Rev Microbiol 36:318–339
Tiraferri A, Vecitis CD, Elimelech M (2011) Covalent binding of single-walled carbon nanotubes to polyamide membranes for antimicrobial surface properties. ACS Appl Mater Interfaces 3:2869–2877. doi:10.1021/am200536p
Tranchida PQ, Franchina FA, Dugo P, Mondello L (2015) Comprehensive two‐dimensional gas chromatography‐mass spectrometry: recent evolution and current trends. Mass Spectrom Rev
Ulbricht M (2006) Advanced functional polymer membranes. Polymer 47:2217–2262
Upadhyay RK, Sharma M, Singh DK, Amritphale SS, Chandra N (2012) Photo degradation of synthetic dyes using cadmium sulfide nanoparticles synthesized in the presence of different capping agents. Sep Purif Technol 88:39–45. doi:10.1016/j.seppur.2011.11.040
Upendar K, Sri Hari Kumar A, Lingaiah N, Rama Rao KS, Sai Prasad PS (2012) Low-temperature CO2 adsorption on alkali metal titanate nanotubes. Int J Greenhouse Gas Control 10:191–198. doi:10.1016/j.ijggc.2012.06.008
Usui Y et al (2008) Carbon nanotubes with high bone-tissue compatibility and bone-formation acceleration effects. Small 4:240–246. doi:10.1002/smll.200700670
Vargas-Reus MA, Memarzadeh K, Huang J, Ren GG, Allaker RP (2012) Antimicrobial activity of nanoparticulate metal oxides against peri-implantitis pathogens. Int J Antimicrob Agents 40:135–139. doi:10.1016/j.ijantimicag.2012.04.012
Vatanpour V, Madaeni SS, Khataee AR, Salehi E, Zinadini S, Monfared HA (2012) TiO2 embedded mixed matrix PES nanocomposite membranes: influence of different sizes and types of nanoparticles on antifouling and performance. Desalination 292:19–29. doi:10.1016/j.desal.2012.02.006
Vecitis CD, Zodrow KR, Kang S, Elimelech M (2010) Electronic-structure-dependent bacterial cytotoxicity of single-walled carbon nanotubes. ACS Nano 4:5471–5479. doi:10.1021/nn101558x
Vecitis CD, Schnoor MH, Rahaman MS, Schiffman JD, Elimelech M (2011) Electrochemical multiwalled carbon nanotube filter for viral and bacterial removal and inactivation. Environ Sci Technol 45:3672–3679. doi:10.1021/es2000062
Venkata Ramana DK, Yu JS, Seshaiah K (2013) Silver nanoparticles deposited multiwalled carbon nanotubes for removal of Cu(II) and Cd(II) from water: surface, kinetic, equilibrium, and thermal adsorption properties. Chem Eng J 223:806–815. doi:10.1016/j.cej.2013.03.001
Venkatesham V, Madhu GM, Satyanarayana SV, Preetham HS (2013) Adsorption of lead on gel combustion derived nano ZnO. Proc Eng 51:308–313. doi:10.1016/j.proeng.2013.01.041
Vikesland PJ, Wigginton KR (2010) Nanomaterial enabled biosensors for pathogen monitoring—a review. Environ Sci Technol 44:3656–3669
Volkert AA, Haes AJ (2014) Advancements in nanosensors using plastic antibodies. Analyst 139:21–31. doi:10.1039/C3AN01725G
Vuković GD, Marinković AD, Čolić M, Ristić MĐ, Aleksić R, Perić-Grujić AA, Uskoković PS (2010a) Removal of cadmium from aqueous solutions by oxidized and ethylenediamine-functionalized multi-walled carbon nanotubes. Chem Eng J 157:238–248. doi:10.1016/j.cej.2009.11.026
Vuković GD, Tomić SZ, Marinković AD, Radmilović V, Uskoković PS, Čolić M (2010b) The response of peritoneal macrophages to dapsone covalently attached on the surface of carbon nanotubes. Carbon 48:3066–3078. doi:10.1016/j.carbon.2010.04.043
Vuković GD, Marinković AD, Škapin SD, Ristić MĐ, Aleksić R, Perić-Grujić AA, Uskoković PS (2011) Removal of lead from water by amino modified multi-walled carbon nanotubes. Chem Eng J 173:855–865. doi:10.1016/j.cej.2011.08.036
Wang A, Jing H (2014) Tunable catalytic activities and selectivities of metal ion doped TiO2 nanoparticles—oxidation of organic compounds. Dalton Trans 43:1011–1018
Wang HY, Lua AC (2012) Development of metallic nickel nanoparticle catalyst for the decomposition of methane into hydrogen and carbon nanofibers. J Phys Chem C 116:26765–26775. doi:10.1021/jp306519t
Wang JL, Xu LJ (2012) Advanced oxidation processes for wastewater treatment: formation of hydroxyl radical and application. Crit Rev Environ Sci Technol 42:251–325
Wang S, Guillen G, Hoek EMV (2005) Direct observation of microbial adhesion to membranes. Environ Sci Technol 39:6461–6469. doi:10.1021/es050188s
Wang Y-Q, Su Y-L, Sun Q, Ma X-L, Jiang Z-Y (2006) Generation of anti-biofouling ultrafiltration membrane surface by blending novel branched amphiphilic polymers with polyethersulfone. J Membr Sci 286:228–236. doi:10.1016/j.memsci.2006.09.040
Wang H, Zhou A, Peng F, Yu H, Yang J (2007a) Mechanism study on adsorption of acidified multiwalled carbon nanotubes to Pb(II). J Colloid Interface Sci 316:277–283. doi:10.1016/j.jcis.2007.07.075
Wang HJ, Zhou AL, Peng F, Yu H, Chen LF (2007b) Adsorption characteristic of acidified carbon nanotubes for heavy metal Pb(II) in aqueous solution. Mater Sci Eng A 466:201–206. doi:10.1016/j.msea.2007.02.097
Wang S-G, Gong W-X, Liu X-W, Yao Y-W, Gao B-Y, Yue Q-Y (2007c) Removal of lead(II) from aqueous solution by adsorption onto manganese oxide-coated carbon nanotubes. Sep Purif Technol 58:17–23. doi:10.1016/j.seppur.2007.07.006
Wang WD, Serp P, Kalck P, Silva CG, Faria JL (2008a) Preparation and characterization of nanostructured MWCNT-TiO2 composite materials for photocatalytic water treatment applications. Mater Res Bull 43:958–967. doi:10.1016/j.materresbull.2007.04.032
Wang X, Chen C, Liu H, Ma J (2008b) Preparation and characterization of PAA/PVDF membrane-immobilized Pd/Fe nanoparticles for dechlorination of trichloroacetic acid. Water Res 42:4656–4664. doi:10.1016/j.watres.2008.08.005
Wang L et al (2009) Simple, rapid, sensitive, and versatile SWNT–paper sensor for environmental toxin detection competitive with ELISA. Nano Lett 9:4147–4152. doi:10.1021/nl902368r
Wang L, Ma W, Xu L, Chen W, Zhu Y, Xu C, Kotov NA (2010a) Nanoparticle-based environmental sensors. Mater Sci Eng R Rep 70:265–274. doi:10.1016/j.mser.2010.06.012
Wang Z, Yu X, Pan B, Xing B (2010b) Norfloxacin sorption and its thermodynamics on surface-modified carbon nanotubes. Environ Sci Technol 44:978–984. doi:10.1021/es902775u
Wang J et al (2013a) Adsorption of Cu(II) on oxidized multi-walled carbon nanotubes in the presence of hydroxylated and carboxylated fullerenes. PLoS ONE 8, e72475. doi:10.1371/journal.pone.0072475
Wang X, Yang J, Zhu M, Li F (2013b) Characterization and regeneration of Pd/Fe nanoparticles immobilized in modified PVDF membrane. J Taiwan Inst Chem Eng 44:386–392. doi:10.1016/j.jtice.2012.12.007
Wang Y, Zhu Y, Wu S (2013c) A new nano CaO-based CO2 adsorbent prepared using an adsorption phase technique. Chem Eng J 218:39–45. doi:10.1016/j.cej.2012.11.095
Wang K, Zhao P, Guo X, Li Y, Han D, Chao Y (2014a) Enhancement of reactivity in Li4SiO4-based sorbents from the nano-sized rice husk ash for high-temperature CO2 capture. Energy Convers Manag 81:447–454. doi:10.1016/j.enconman.2014.02.054
Wang Y, Fang Z, Kang Y, Tsang EP (2014b) Immobilization and phytotoxicity of chromium in contaminated soil remediated by CMC-stabilized nZVI. J Hazard Mater. doi:10.1016/j.jhazmat.2014.04.056
Wang Y, Fang Z, Liang B, Tsang EP (2014c) Remediation of hexavalent chromium contaminated soil by stabilized nanoscale zero-valent iron prepared from steel pickling waste liquor. Chem Eng J 247:283–290. doi:10.1016/j.cej.2014.03.011
Warheit DBWT, Reeda KL, Frerichs S, Sayes CM (2007) Pulmonary toxicity study in rats with three forms of ultrafine-TiO2 particles: differential responses related to surface properties. Toxicology 230:90–104
Weis A, Bird MR, Nyström M, Wright C (2005) The influence of morphology, hydrophobicity and charge upon the long-term performance of ultrafiltration membranes fouled with spent sulphite liquor. Desalination 175:73–85. doi:10.1016/j.desal.2004.09.024
Wildgoose GG, Banks CE, Leventis HC, Compton RG (2006) Chemically modified carbon nanotubes for use in electroanalysis. Microchim Acta 152:187–214. doi:10.1007/s00604-005-0449-x
Williams G, Seger B, Kamat PV (2008) TiO2-graphene nanocomposites. UV-assisted photocatalytic reduction of graphene oxide. ACS Nano 2:1487–1491. doi:10.1021/nn800251f
Woan K, Pyrgiotakis G, Sigmund W (2009) Photocatalytic carbon‐nanotube–TiO2 composites. Adv Mater 21:2233–2239
Wu L, Ritchie SMC (2008) Enhanced dechlorination of trichloroethylene by membrane-supported Pd-coated iron nanoparticles. Environ Prog 27:218–224. doi:10.1002/ep.10277
Wu L, Shamsuzzoha M, Ritchie SMC (2005) Preparation of cellulose acetate supported zero-valent iron nanoparticles for the dechlorination of trichloroethylene in water. J Nanoparticle Res 7:469–476. doi:10.1007/s11051-005-4271-5
Wu G, Gan S, Cui L, Xu Y (2008) Preparation and characterization of PES/TiO2 composite membranes. Appl Surf Sci 254:7080–7086. doi:10.1016/j.apsusc.2008.05.221
Wu C-S, Khaing Oo MK, Fan X (2010) Highly sensitive multiplexed heavy metal detection using quantum-dot-labeled DNAzymes. ACS Nano 4:5897–5904. doi:10.1021/nn1021988
Wu C-M, Baltrusaitis J, Gillan EG, Grassian VH (2011) Sulfur dioxide adsorption on ZnO nanoparticles and nanorods. J Phys Chem C 115:10164–10172
Wu HB, Hng HH, Lou XWD (2012) Direct synthesis of anatase TiO2 nanowires with enhanced photocatalytic activity. Adv Mater 24:2567–2571
Xi W, Geissen S-u (2001) Separation of titanium dioxide from photocatalytically treated water by cross-flow microfiltration. Water Res 35:1256–1262
Xiao J, Xie Y, Cao H (2015) Organic pollutants removal in wastewater by heterogeneous photocatalytic ozonation. Chemosphere 121:1–17. doi:10.1016/j.chemosphere.2014.10.072
Xie Y, Fang Z, Cheng W, Tsang PE, Zhao D (2014) Remediation of polybrominated diphenyl ethers in soil using Ni/Fe bimetallic nanoparticles: influencing factors, kinetics and mechanism. Sci Total Environ 485–486:363–370. doi:10.1016/j.scitotenv.2014.03.039
Xin X et al (2012) Highly efficient removal of heavy metal ions by amine-functionalized mesoporous Fe3O4 nanoparticles. Chem Eng J 184:132–140. doi:10.1016/j.cej.2012.01.016
Xing Z, Asiri AM, Obaid AY, Sun X, Ge X (2014) Carbon nanofiber-templated mesoporous TiO2 nanotubes as a high-capacity anode material for lithium-ion batteries. RSC Adv 4:9061–9063
Xiong Z, He F, Zhao DY, Barnett MO (2009) Immobilization of mercury in sediment using stabilized iron sulfide nanoparticles. Water Res 43:5171–5179
Xiu Z-M, Ma J, Alvarez PJJ (2011) Differential effect of common ligands and molecular oxygen on antimicrobial activity of silver nanoparticles versus silver ions. Environ Sci Technol 45:9003–9008. doi:10.1021/es201918f
Xiu Z-m, Zhang Q-b, Puppala HL, Colvin VL, Alvarez PJJ (2012) Negligible particle-specific antibacterial activity of silver nanoparticles. Nano Lett 12:4271–4275. doi:10.1021/nl301934w
Xu Y, Zhao D (2007) Reductive immobilization of chromate in water and soil using stabilized iron nanoparticles. Water Res 41:2101–2108. doi:10.1016/j.watres.2007.02.037
Xu D, Tan X, Chen C, Wang X (2008) Removal of Pb(II) from aqueous solution by oxidized multiwalled carbon nanotubes. J Hazard Mater 154:407–416. doi:10.1016/j.jhazmat.2007.10.059
Xu Y-j, Rosa A, Liu X, Su D-s (2011) Characterization and use of functionalized carbon nanotubes for the adsorption of heavy metal anions. New Carbon Mater 26:57–62. doi:10.1016/S1872-5805(11)60066-8
Yamamoto O (2001) Influence of particle size on the antibacterial activity of zinc oxide. Int J Inorg Mater 3:643–646. doi:10.1016/S1466-6049(01)00197-0
Yan L, Li YS, Xiang CB, Xianda S (2006) Effect of nano-sized Al2O3-particle addition on PVDF ultrafiltration membrane performance. J Membr Sci 276:162–167. doi:10.1016/j.memsci.2005.09.044
Yan XM, Shi BY, Lu JJ, Feng CH, Wang DS, Tang HX (2008) Adsorption and desorption of atrazine on carbon nanotubes. J Colloid Interface Sci 321:30–38. doi:10.1016/j.jcis.2008.01.047
Yang GCC, Chang Y-I (2011) Integration of emulsified nanoiron injection with the electrokinetic process for remediation of trichloroethylene in saturated soil. Sep Purif Technol 79:278–284. doi:10.1016/j.seppur.2011.03.004
Yang K, Xing B (2009) Adsorption of fulvic acid by carbon nanotubes from water. Environ Pollut 157:1095–1100. doi:10.1016/j.envpol.2008.11.007
Yang K, Xing B (2010) Adsorption of organic compounds by carbon nanomaterials in aqueous phase: Polanyi theory and its application. Chem Rev 110:5989–6008. doi:10.1021/cr100059s
Yang J, Mosby DE, Casteel SW, Blanchar RW (2001) Lead immobilization using phosphoric acid in a smelter-contaminated urban soil. Environ Sci Technol 35:3553–3559
Yang K, Wu W, Jing Q, Zhu L (2008) Aqueous adsorption of aniline, phenol, and their substitutes by multi-walled carbon nanotubes. Environ Sci Technol 42:7931–7936. doi:10.1021/es801463v
Yang H-L, Lin JC-T, Huang C (2009a) Application of nanosilver surface modification to RO membrane and spacer for mitigating biofouling in seawater desalination. Water Res 43:3777–3786. doi:10.1016/j.watres.2009.06.002
Yang HG et al (2009b) Solvothermal synthesis and photoreactivity of anatase TiO2 nanosheets with dominant {001} facets. J Am Chem Soc 131:4078–4083. doi:10.1021/ja808790p
Yang C, Mamouni J, Tang Y, Yang L (2010a) Antimicrobial activity of single-walled carbon nanotubes: length effect. Langmuir 26:16013–16019. doi:10.1021/la103110g
Yang K, Wu W, Jing Q, Jiang W, Xing B (2010b) Competitive adsorption of naphthalene with 2,4-dichlorophenol and 4-chloroaniline on multiwalled carbon nanotubes. Environ Sci Technol 44:3021–3027. doi:10.1021/es100018a
Yang N, Liu Y, Wen H, Tang Z, Zhao H, Li Y, Wang D (2013a) Photocatalytic properties of graphdiyne and graphene modified TiO2: from theory to experiment. ACS Nano 7:1504–1512
Yang W, Ding P, Zhou L, Yu J, Chen X, Jiao F (2013b) Preparation of diamine modified mesoporous silica on multi-walled carbon nanotubes for the adsorption of heavy metals in aqueous solution. Appl Surf Sci 282:38–45. doi:10.1016/j.apsusc.2013.05.028
Yang X, Shen Z, Zhang B, Yang J, Hong W-X, Zhuang Z, Liu J (2013c) Silica nanoparticles capture atmospheric lead: implications in the treatment of environmental heavy metal pollution. Chemosphere 90:653–656. doi:10.1016/j.chemosphere.2012.09.033
Yao Y, Bing H, Feifei X, Xiaofeng C (2011) Equilibrium and kinetic studies of methyl orange adsorption on multiwalled carbon nanotubes. Chem Eng J 170:82–89. doi:10.1016/j.cej.2011.03.031
Yap CK, Azmizan A, Hanif M (2011) Biomonitoring of trace metals (Fe, Cu, and Ni) in the mangrove area of Peninsular Malaysia using different soft tissues of flat tree oyster Isognomon alatus. Water Air Soil Pollut 218:19–36
Yassıtepe E, Yatmaz HC, Öztürk C, Öztürk K, Duran C (2008) Photocatalytic efficiency of ZnO plates in degradation of azo dye solutions. J Photochem Photobiol A Chem 198:1–6. doi:10.1016/j.jphotochem.2008.02.007
Yildiz O, Bradford PD (2013) Aligned carbon nanotube sheet high efficiency particulate air filters. Carbon 64:295–304. doi:10.1016/j.carbon.2013.07.066
You Y, Han J, Chiu PC, Jin Y (2005) Removal and inactivation of waterborne viruses using zerovalent iron. Environ Sci Technol 39:9263–9269. doi:10.1021/es050829j
Young P, Lu YJ, Terrill R, Li J (2005) High-sensitivity NO2 detection with carbon nanotube-gold nanoparticle composite films. J Nanosci Nanotechnol 5:1509–1513. doi:10.1166/jnn.2005.323
Yu H, Zhang X, Zhang Y, Liu J, Zhang H (2013) Development of a hydrophilic PES ultrafiltration membrane containing SiO2@N-Halamine nanoparticles with both organic antifouling and antibacterial properties. Desalination 326:69–76. doi:10.1016/j.desal.2013.07.018
Yu J-G et al (2014) Aqueous adsorption and removal of organic contaminants by carbon nanotubes. Sci Total Environ 482–483:241–251. doi:10.1016/j.scitotenv.2014.02.129
Zang L (2011) Energy efficiency and renewable energy through nanotechnology. Springer, London
Zhang W-x (2003) Nanoscale iron particles for environmental remediation: an overview. J Nanoparticle Res 5:323–332. doi:10.1023/A:1025520116015
Zhang D, Qiu R, Song L, Eric B, Mo Y, Huang X (2009) Role of oxygen active species in the photocatalytic degradation of phenol using polymer sensitized TiO2 under visible light irradiation. J Hazard Mater 163:843–847. doi:10.1016/j.jhazmat.2008.07.036
Zhang D, Pan B, Zhang H, Ning P, Xing B (2010) Contribution of different sulfamethoxazole species to their overall adsorption on functionalized carbon nanotubes. Environ Sci Technol 44:3806–3811. doi:10.1021/es903851q
Zhang L, Song X, Liu X, Yang L, Pan F, Lv J (2011a) Studies on the removal of tetracycline by multi-walled carbon nanotubes. Chem Eng J 178:26–33. doi:10.1016/j.cej.2011.09.127
Zhang L, Xu T, Liu X, Zhang Y, Jin H (2011b) Adsorption behavior of multi-walled carbon nanotubes for the removal of olaquindox from aqueous solutions. J Hazard Mater 197:389–396. doi:10.1016/j.jhazmat.2011.09.100
Zhang X, Qu Z, Li X, Zhao Q, Wang Y, Quan X (2011c) Low temperature CO oxidation over Ag/SBA-15 nanocomposites prepared via in-situ “pH-adjusting” method. Catal Commun 16:11–14. doi:10.1016/j.catcom.2011.08.030
Zhang C, Sui J, Li J, Tang Y, Cai W (2012) Efficient removal of heavy metal ions by thiol-functionalized superparamagnetic carbon nanotubes. Chem Eng J 210:45–52. doi:10.1016/j.cej.2012.08.062
Zhang G et al (2014) Visible light-sensitized S, N and C co-doped polymorphic TiO2 for photocatalytic destruction of microcystin-LR. Appl Catal B Environ 144:614–621. doi:10.1016/j.apcatb.2013.07.058
Zhao J (2009) Turning to Nanotechnology for Pollution Control: Applications of Nanoparticles. Dartmouth undergraduate journal of science
Zhao L et al (2010a) Synthesis, characterization and adsorptive performance of MgFe2O4 nanospheres for SO2 removal. J Hazard Mater 184:704–709. doi:10.1016/j.jhazmat.2010.08.096
Zhao X, Wang J, Wu F, Wang T, Cai Y, Shi Y, Jiang G (2010b) Removal of fluoride from aqueous media by Fe3O4@Al(OH)3 magnetic nanoparticles. J Hazard Mater 173:102–109. doi:10.1016/j.jhazmat.2009.08.054
Zhao S, Zou L, Tang CY, Mulcahy D (2012a) Recent developments in forward osmosis: opportunities and challenges. J Membr Sci 396:1–21
Zhao W, Wang Z, Shen X, Li J, Xu C, Gan Z (2012b) Hydrogen generation via photoelectrocatalytic water splitting using a tungsten trioxide catalyst under visible light irradiation. Int J Hydrog Energy 37:908–915. doi:10.1016/j.ijhydene.2011.03.161
Zhou R, Hu G, Yu R, Pan C, Wang ZL (2015) Piezotronic effect enhanced detection of flammable/toxic gases by ZnO micro/nanowire sensors. Nano Energy. doi:10.1016/j.nanoen.2015.01.036
Zodrow K, Brunet L, Mahendra S, Li D, Zhang A, Li Q, Alvarez PJJ (2009) Polysulfone ultrafiltration membranes impregnated with silver nanoparticles show improved biofouling resistance and virus removal. Water Res 43:715–723. doi:10.1016/j.watres.2008.11.014
Acknowledgments
The authors would like to express their thanks to the University of Malaya UMRG for their support.
Author information
Authors and Affiliations
Corresponding author
Additional information
Responsible editor: Philippe Garrigues
Rights and permissions
About this article
Cite this article
Ibrahim, R.K., Hayyan, M., AlSaadi, M.A. et al. Environmental application of nanotechnology: air, soil, and water. Environ Sci Pollut Res 23, 13754–13788 (2016). https://doi.org/10.1007/s11356-016-6457-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11356-016-6457-z