1 Introduction

Increasingly, severe environmental pollution is one of the urgent problems to be solved in the world. To solve the environmental pollution problems, many traditional technologies have been adopted, such as incineration, biological method, stripping method, and activated carbon adsorption method. However, these methods will produce secondary pollution, which is more harmful to the environment. Semiconductor photocatalytic technology, as a green environmental technology, with its high efficiency and environmental friendliness, has been widely used. Semiconductor photocatalyst can absorb and utilize solar energy more effectively and is an active ecological purification material [1,2,3,4,5]. The photocatalysts, such as mixed transition metal oxides, titanate, niobate, and tantalite, can only absorb ultraviolet light,but ultraviolet radiation accounts for only 4% of the incident solar energy. To improve the conversion efficiency of solar energy [6,7,8], the basic approach is to develop and design visible-light-driven photocatalysts.

Recently, researchers are increasingly interested in low-cost and high-efficiency photocatalysts; Zinc ferrite (ZnFe2O4) with the spinel crystal structure and narrow Eg (1.9 eV) is an important research direction of the photocatalysts. It has a wide range of functional characteristics in practical applications, such as magnetism, visible light response, and excellent photochemical stability [9,10,11,12]. However, single ZnFe2O4 is widely restricted and ascribed to the quick rejoining of photoexcited charge carriers and natural agglomeration, which is limiting its practical application. Therefore, it is significant to develop a method to improve charge separation and photocatalytic activities of ZnFe2O4.

Construction of heterojunctions is a feasible and straightforward way to enhance photocatalytic performance of single photocatalysts, and the modified composite photocatalysts have excellent electronic properties and effective separation of photo-generated electron and hole pairs [13, 14]. Molybdenum disulfide (MoS2) is a graphene-type transition metal dichalcogenides compound with an ultrathin layered structure and a suitable energy bandgap [15, 16], which has significant potential applications in the field of nanoelectronics, optoelectronics, and flexible devices. Furthermore, MoS2 has the advantages of low cost, near-zero Gibbs free energy, excellent rich edge structure, and large surface area [17,18,19,20,21,22,23,24] and has been widely used in the study of photocatalysis.. The strategy of integrating ZnFe2O4 with MoS2 nanosheets was proposed, which can improve the light absorption ability of the composite photocatalysts because of the introduction of nanosheets structure of MoS2. Meanwhile, magnetic separation can effectively prevent the loss of the catalysts in the recovery process, and it is more environmentally friendly to show broad application potential.

In the study, high photocatalytic activity and easy recovery photocatalysts such MoS2/ZnFe2O4 heterostructure photocatalysts were synthesized by the hydrothermal method. The introduction of nanosheet structure of MoS2 and heterostructures formed by ZnFe2O4 and MoS2 can effectively improve light absorption ability, increase reactive sites, effectively inhibit recombination of the photo-generated electrons and holes, accelerate the photo-generated electrons transfer speed, and enhance photocatalytic performance of the photocatalysts.

2 Experimental

2.1 Material

(NH4)6Mo7O24·4H2O, thiourea, Fe(NO3)3·9H2O, Zn(NO3)2·6H2O, tartaric acid, and sodium hydroxide (NaOH) were purchased from Sinopharm Chemical Reagent Co., Ltd. All reagents were analytical grade and used without further purification in this research.

2.2 Preparation of MoS2

MoS2 were synthesized by the conventional hydrothermal method [25]. 0.8 g of (NH4)6Mo7O24·4H2O and 6.4 g of thiourea were dissolved in 80 mL of deionized water and stirred for 1 h. The homogeneous solution was transferred into PTEF-lined autoclave and maintained at 200 °C for 24 h. Then, the samples were obtained by centrifugation, washed with deionized water and ethanol, and dried in a vacuum oven at 60 °C.

2.3 2.3. Preparation of ZnFe2O4 [10]

20 mmol Fe(NO3)3·9H2O and 10 mmol Zn(NO3)2·6H2O were dissolved in 30 mL of deionized water and stirred for 30 min. After that, 60 mmol tartaric acid was added to solutions mentioned above and stirred for 30 min, 220 mmol NaOH was added and stirred for 30 min, the mixture solution was transferred into PTEF-lined autoclave and maintained at 180 °C for 24 h. Then, the samples were obtained by magnetic separation method, washed with deionized water and ethanol, and dried in a vacuum oven at 60 °C.

2.4 Preparation of MoS2/ZnFe2O4 photocatalysts

MoS2/ZnFe2O4 photocatalysts were synthesized by a facile hydrothermal method. The prepared ZnFe2O4 of certain quality was sonicated thoroughly in 80 mL deionized water for 1 h. 0.8 g of (NH4)6Mo7O24·4H2O and 6.4 g of thiourea were dissolved in 80 mL of deionized water and stirred for 1 h. The homogeneous solution was transferred into PTEF-lined autoclave and maintained at 200 °C for 24 h. Then, the samples were obtained by magnetic separation method, washed with deionized water and ethanol, and dried in a vacuum oven at 60 °C.

The quality of ZnFe2O4 added is controlled to be 1.44 g, 0.72 g, 0.29 g, and 0.144 g, and the obtained samples are accordingly marked as MoS2/ZnFe2O4-5%, MoS2/ZnFe2O4-10%, MoS2/ZnFe2O4-25%, and MoS2/ZnFe2O4-50%, respectively.

2.5 Instrumentation

The powder XRD patterns are collected on an X-ray diffractometer (SMART LAB, RIGAKU, Japan) with the scanning range of 2θ = 10°–70°. The scanning electron microscope (SEM) images were examined with S-8010 (HITACHI, Japan). The transmission electron microscope (TEM) micrographs were taken with an HT-7700 (HITACHI, Japan) operated at 100 kV. The surface chemical compositions were investigated by X-ray photoelectron spectroscopy (XPS) with an Omicron ESCALAB 250Xi (Thermo Fisher) probe spectrometer. Fourier transform-infrared (FT-IR) spectra were tested by Nicolet Model Nexus 470 FT-IR (Thermo Fisher, American). The UV–visible diffuse reflectance spectrum (UV–vis DRS) was recorded in a UV-3600 spectrophotometer (Shimadzu, Japan) and BaSO4 to test all the samples for reference. Photoluminescence (PL) spectra were obtained on F-7000 (Hitachi, Japan) fluorescence spectrophotometer. Measurement of the magnetic property of the prepared photocatalysts was tested by using a vibrating sample magnetometer (VSM, HH-15, China). The visible light irradiation was obtained from a 300 W xenon lamp (CEL-HXF300, Beijing China Education Au-light Co. Ltd., China) with a 420 nm cutoff filter. Electron spin resonance (ESR) was tested on an electron paramagnetic resonance spectrometer (A300-10/12, Bruker).

The electrochemical and photoelectrochemical properties were tested on an electrochemical system (CHI-660B, China). The photoelectric responses of the obtained photocatalysts were measured at 0.0 V with ITO as a working electrode, a platinum wire as a counter electrode, and a standard calomel electrode (SCE) as a reference electrode.

2.6 Photocatalytic activity experiments

The study evaluated the photocatalytic activity of MoS2, ZnFe2O4, and MoS2/ZnFe2O4 prepared in advance by degradation TC under visible light irradiation. 100 mg photocatalysts were added into 100 mL × 10 mg L−1 TC solution. Firstly, the study used ultrasonication to disperse the photocatalysts for 10 min, and after stirring for 2 h in the dark, the dynamic adsorption equilibrium was achieved between TC and photocatalysts. The solution after the reaction was extracted in a specified interval of time. TC concentration was measured by UV–vis spectroscopy at 275 nm, and the change in concentration was recorded as C/C0 (where C0 was the initial TC concentration, C was the concentration of time t). Other conditions remain unchanged, and TC were directly photolyzed without the photocatalysts in the reaction system.

3 Result and discussion

3.1 Material characterization

The XRD patterns of prepared MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalyst were shown in Fig. 1. In the figure, for the spectrum of MoS2, only four broad XRD peaks at 2θ = 14°, 33.3°, 39.6°, and 58.5° were found, respectively, indexing to the (002), (101), (103), and (110) crystal plane of MoS2 (JCPDS card No. 37-1492) [25], which revealed the formation of MoS2 in hydrothermal process. As shown in the figure, the original ZnFe2O4 shows (220), (311), (400), (422), (511), and (440) diffraction peaks on the crystal plane at 2θ values of 30.0°, 35.3°, 43.0°, 53.2°, 56.7°, and 62.2°, respectively, which were indexed to spinel-type ZnFe2O4 (JCPDS card No. 22-1012) [26]. MoS2/ZnFe2O4 photocatalysts show similar diffraction peaks to those of the original ZnFe2O4. The XRD patterns of the ZnFe2O4 did not change, while the loading amount of MoS2 increased from 5 to 50%, the diffraction peaks of MoS2 only exist in MoS2/ZnFe2O4-25% and MoS2/ZnFe2O4-50% photocatalysts, and no significant signal of MoS2 was discovered from the spectra of other MoS2/ZnFe2O4 photocatalysts, probably due to its low loading amount and high dispersion of MoS2 in the MoS2/ZnFe2O4 photocatalysts.

Fig. 1
figure 1

XRD patterns of the pure MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalysts

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The FT-IR spectra of pure MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalysts are seen in Fig. 2. Two main broad peaks in 900 and 450 cm−1 were ascribed to metal–oxygen (M–O), determiing the existence of spinel ferrite [27]. The maximum value seen between 600 and 500 cm−1 corresponds to the stretching vibration of the primary metal at A-site, Mtetra ↔ O, in comparison the minimum peak showed from 450 to 400 cm−1 ascribed to the stretching vibration of B-site metal, Mocta ↔ O. The MoS2 had two characteristic peaks at 1100 and 620 cm−1 in the FT-IR spectrum and the intensity of the two unique peaks of MoS2 weakened in the MoS2/ZnFe2O4 photocatalysts.

Fig. 2
figure 2

FT-IR spectra of the pure MoS2, ZnFe2O4, and MoS2/ZnFe2O4 25% photocatalysts

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The study determined the light absorption capacity of the photocatalysts by UV–vis DRS. Figure 3a displays the UV–vis DRS of the MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalysts. The MoS2 and MoS2/ZnFe2O4 photocatalysts exhibit higher light-absorbing property than ZnFe2O4 at wavelength from 600 to 800 nm, and the spectra of MoS2/ZnFe2O4 25% showed a slight red shift, since MoS2 as a thin layer structure was uniformly deposited on ZnFe2O4 to make the light transmit evenly, which is conducive to improving the light absorption of the photocatalysts. Figure 3b is the correlation curve of (αhν)2 versus hν to obtain the bandgap of the MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalysts. In line with Kubelka–Munk formula, the bandgap (Eg) of the MoS2, MoS2/ZnFe2O4 25%, and ZnFe2O4 photocatalysts were calculated to be 1.25 eV, 1.78 eV, and 1.97 eV, respectively. The electrons on the valence band (VB) are more easily excited for the smaller bandgap photocatalysts under visible light and jump to the conduction band (CB), which is conducive to the photocatalytic response. Consequently, MoS2/ZnFe2O4 photocatalysts can effectively utilize visible light and participate in photocatalytic reaction.

Fig. 3
figure 3

UV–vis DRS (a) and estimation of bandgap energy (b) of MoS2, ZnFe2O4, and MoS2/ZnFe2O4 25% photocatalysts

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The composition of MoS2/ZnFe2O4 and the chemical states of different elements were determined by XPS. As can be seen in Fig. 4, in line with the XPS observations, Mo, S, Zn, Fe, and O elements are detected in the MoS2/ZnFe2O4 photocatalysts (Fig. 4a). The high-resolution Mo 3d XPS spectrum (Fig. 4b) shows the binding energies peaks of Mo 3d5/2 and Mo 3d3/2 at 229.0 and 232.1 eV, respectively, which are assigned to Mo4+ in MoS2 [28,29,30]. The S 2p XPS spectrum (Fig. 4c) determines the existence of both monosulfide S2− (S 2p3/2 and S 2p1/2 at 161.7 and 162.8 eV, respectively), which are consistent with the previous literature reports on MoS2 [15, 28, 29]. The symmetric peaks at 1021.3 eV and 1044.4 eV are ascribed to Zn 2p3/2 and Zn 2p1/2, respectively (Fig. 4d), and the peaks at 712.7 eV and 725.4 eV are indexed to Fe 2p3/2 and Fe 2p1/2 (Fig. 4e) [1]. Furthermore, the peaks at 531.1 eV and 529.7 eV can belong to the binding energy of O 1s (Fig. 4f).

Fig. 4
figure 4

XPS spectra of the MoS2/ZnFe2O4 25% photocatalysts: a XPS survey, b Mo 3d, c S 1s, d Zn 2p, e Fe 2p, and f O 1s

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The morphology and size of the photocatalysts were studied by SEM. In Fig. 5a, the SEM image of MoS2 reveals that the MoS2 microspheres were composed of nanosheet with the dimension in the range of 300–400 nm assembled by densely packed petals. In Fig. 5b, it can be seen that the morphology of the ZnFe2O4 is particle shape and the particle size is uniform with an average diameter of 20 nm, and due to its strong magnetism, some ZnFe2O4 particles agglomerated. In Fig. 6a, some ZnFe2O4 particles evenly covered on the MoS2 nanosheets. The results of EDX measurement further confirm the coexistence of Zn, Fe, O, S, and Mo elements in the MoS2/ZnFe2O4 photocatalysts (Fig. 6b). The elemental mapping of the MoS2/ZnFe2O4 photocatalysts is shown in Fig. 7, which indicated the uniform distribution of elements in the MoS2/ZnFe2O4 photocatalysts.

Fig. 5
figure 5

SEM images of the ZnFe2O4 and MoS2

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Fig. 6
figure 6

SEM image and EDS spectra of the MoS2/ZnFe2O4 25% photocatalysts

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Fig. 7
figure 7

The element mapping images of the MoS2/ZnFe2O4 25% photocatalysts: a Layered image, b O, c S, d Fe, e Zn, and f Mo

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The fine microstructure of the photocatalysts were observed by TEM. Figure 8 exhibits the TEM images of the MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalysts. In Fig. 8a, the results show that ZnFe2O4 particles are spherical with an average diameter of 20 nm. In Fig. 8b, it can be seen that MoS2 is a flower-shaped structure composed of nanosheets. ZnFe2O4 were deposited on MoS2 nanosheets and heterogeneous structures were formed between ZnFe2O4 and MoS2. Therefore, the light absorption ability of the photocatalysts were improved because of the introduction of nanosheets structure of MoS2 and the photo-generated electrons by the ZnFe2O4 in the photocatalytic process can be moved to the MoS2 nanosheets, consequently, reducing the recombination of photo-generated carriers.

Fig. 8
figure 8

TEM images of the ZnFe2O4, MoS2, and MoS2/ZnFe2O4 25% photocatalysts

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Figure 9 shows the magnetic hysteresis loop of ZnFe2O4 and MoS2/ZnFe2O4 photocatalysts. The magnetization curves of the two photocatalysts are symmetrical, and no hysteresis is observed at the origin, indicating that the photocatalysts have superparamagnetism. The saturation magnetization (Ms) values of two photocatalysts were 11.48 and 4.05 emu g−1, respectively. Although the Ms value was relatively low, the MoS2/ZnFe2O4 photocatalysts could effectively realize magnetic separation and recovery revealed by the inset photograph of Fig. 8. Under the external magnetic field, the MoS2/ZnFe2O4 photocatalysts were rapidly attracted to the wall of the vial to get a transparent solution, to reduce the loss of photocatalysts, and improve the recovery efficiency.

Fig. 9
figure 9

Magnetic hysteresis loop of the ZnFe2O4 and MoS2/ZnFe2O4 25% photocatalysts

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To reveal the capture, migration, and transfer characteristics of electron–hole pairs, PL emission measurement was used to record the PL spectra of the photocatalysts [22]. Figure 10 displays the PL spectra of the MoS2, ZnFe2O4, and MoS2/ZnFe2O4 photocatalysts. The results that MoS2 and ZnFe2O4 showed very potent photoluminescence emissions centered at 470 nm, the photoluminescence have been quenched remarkably on MoS2/ZnFe2O4 photocatalysts, manifesting that the effective photo-generated carriers separation happened, which reveals that the recombination of photo-generated carriers is significantly suppressed, resulting in the increase of highly active species for TC degradation.

Fig. 10
figure 10

PL spectra of the ZnFe2O4, MoS2 and MoS2/ZnFe2O4 25% photocatalysts

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The photocurrent intensity for MoS2/ZnFe2O4 25% photocatalysts is nearly two times and eight times as high as those of ZnFe2O4 and MoS2 (Fig. 11a); the result shows that the separation efficiency of electron–hole pairs in MoS2/ZnFe2O4 25% photocatalysts is higher. Therefore, the photocurrent response further proves that heterostructures can improve the separation efficiency of the photo-generated carriers. At the same time, the EIS test was also used to study the process of the charge transfer resistance (Fig. 11b). The values of the radius of the Nyquist circle are consistent with charge transfer resistance [3]. In terms of arc radius, the MoS2/ZnFe2O4 25% photocatalysts show a considerably smaller radius than MoS2 and ZnFe2O4. These results coherently demonstrate that MoS2/ZnFe2O4 photocatalysts have better photoelectric properties which could improve the separation of the photo-generated carriers in the degradation process.

Fig. 11
figure 11

Transient photocurrent responses spectra (a), electrochemical impedance spectra (b) of the ZnFe2O4, MoS2, and MoS2/ZnFe2O4 25% photocatalysts

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3.2 Photocatalytic performance

The study evaluated the photocatalytic activity of the photocatalysts by TC photodegradation. Figure 12 shows the photocatalytic performance of different photocatalysts. Through the blank experiment, TC concentration remained stable for 180 min, demonstrating that the photolysis of TC was neglected without photocatalyst use. The photocatalytic degradation efficiency of TC was low when single MoS2 and ZnFe2O4 photocatalysts were used. The photocatalytic activity of MoS2/ZnFe2O4 photocatalysts is much higher than MoS2 and ZnFe2O4 photocatalysts. MoS2/ZnFe2O4-25% photocatalysts show the highest photocatalytic activity with degradation rate of 95%, and the result is consistent with the UV–vis DRS of MoS2/ZnFe2O4-25% photocatalysts, which has the highest light absorption capacity.

Fig. 12
figure 12

The degradation rate of MoS2/ZnFe2O4 photocatalysts with different composite proportions.

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3.3 Active species capture experiments

The main active species were studied through the active species capturing experiments in the photocatalytic process. For the sake of further study of the photocatalytic mechanism, it is necessary to define which active species play a significant role in the photodegradation process of TC. Scavengers of superoxide radicals (·O2−), photoexcited holes (h+), and hydroxyl radicals (·OH) were N2, disodium ethylenediaminetetraacetate (Na2-EDTA), and tertbutyl alcohol (tBuOH), respectively [31,32,33]. As shown in Fig. 13, the photocatalytic activity of the MoS2/ZnFe2O4 photocatalysts decreased when N2 was used, suggesting ·O2− were the main active species in the photocatalytic process. When EDTA and tBuOH were used, the photocatalytic activity of the MoS2/ZnFe2O4 photocatalysts decreased slightly, which showed that ·OH and h+ played a smaller role in TC photodegradation. Also, the active species were studied by ESR in the photodegradation process. As can be seen from Fig. 14, ESR signals are weak in the dark, however, it deserves to be mentioned that the six characteristic peaks of ·O2− can be seen in Fig. 14a, which reveals that the ·O2− can be generated in the photodegradation process of TC. The characteristic signals of DMPO-·OH have been observed under visible light irradiation (Fig. 14b), indicating that the ·OH cannot be generated in MoS2/ZnFe2O4 photocatalysts in the photodegradation process. In a word, the ESR results are consistent with the capture experiment of active species and the ·O2− and h+ exist in photodegradation system of MoS2/ZnFe2O4 photocatalysts.

Fig. 13
figure 13

Plots of photo-generated carriers trapping in the system of photocatalytic degradation of TC over MoS2/ZnFe2O4 25% photocatalysts

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Fig. 14
figure 14

ESR spectra of DMPO-·OH (a) and DMPO-·O2− (b) for MoS2/ZnFe2O4 25% photocatalysts

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3.4 Cycle experiments

Stability is a crucial problem to be considered for practical applications. Figure 15 displays the four-cycle experiment of TC photodegradation with MoS2/ZnFe2O4 25% photocatalysts under the same experimental conditions. The photocatalytic activity has no apparent decrease, showing that MoS2/ZnFe2O4 photocatalysts have better photodegradation stability. Figure 16 displays XRD images, SEM picture of MoS2/ZnFe2O4 photocatalysts after the reaction, diffraction peaks of MoS2 (JCPDS card No. 37-1492) [25] and spinel-type ZnFe2O4 (JCPDS card No. 22-1012) [26]., and morphology of MoS2/ZnFe2O4 photocatalysts showing no changes, and these results indicate that MoS2/ZnFe2O4 photocatalysts have excellent photodegradation stability.

Fig. 15
figure 15

The figure of four reaction cycles for photodegradation of TC under visible light irrigation with MoS2/ZnFe2O4 25% photocatalysts

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Fig. 16
figure 16

XRD pattern and SEM image of MoS2/ZnFe2O4 25% photocatalysts after the reaction

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3.5 Reaction mechanism

As illustrated in Fig. 17a, b (XPS valence band), the VB position of MoS2 and ZnFe2O4 are 0.55 eV and 0.47 eV, respectively. Thus, the CB of MoS2 and ZnFe2O4 are calculated to be − 0.70 eV and -1.50 eV, respectively.

Fig. 17
figure 17

XPS valence band spectra of ZnFe2O4 (a) and MoS2 (b)

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The reaction mechanisms of MoS2/ZnFe2O4 photocatalysts include the adsorption and photocatalytic degradation process. The adsorption capacity has a bearing on the specific surface area of MoS2/ZnFe2O4 photocatalysts, and photocatalytic degradation is considered to be a robust oxidation process of active species. Based on these data, the tentative mechanism of photocatalytic degradation was discussed in Fig. 18.

Fig. 18
figure 18

The mechanism of the photodegradation process on the MoS2/ZnFe2O4 photocatalysts

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In the photocatalytic degradation process of MoS2/ZnFe2O4 photocatalysts under visible light illumination, because of its response to visible light, MoS2 and ZnFe2O4 can effectively capture photons and induce electrons to excite from VB to CB. Due to the strong thermodynamic driving force generated by the energy difference between the CB of MoS2 (− 0.70 eV) and ZnFe2O4 (− 1.50 eV), the photo-generated electrons in the CB of ZnFe2O4 are easily transferred to the CB of MoS2 through the heterojunction structure, which effectively inhibit the recombination of electrons and holes in ZnFe2O4. Because the CB potential of MoS2 (− 0.70 eV) is more negative than the standard redox potential of O2/O2− (− 0.046 eV vs NHE), O2 on the MoS2 surface obtain an electron on CB of MoS2 to produce reactive ·O2− and hence oxidizes TC. The photo-generated holes were transferred from VB of MoS2 to the VB of ZnFe2O4 because the VB edge potential value of ZnFe2O4 and MoS2 is below the standard redox potential of ·OH/OH− (1.99 eV vs NHE); therefore, holes on VB of ZnFe2O4 cannot react with absorbed H2O to produce·OH which can directly oxidize TC to produce decomposition products [34]. The close contact interface between MoS2 and ZnFe2O4 can effectively inhibit the recombination of the photo-generated electrons and holes, accelerate the photo-generated electrons transfer speed, and enhance the photocatalytic performance of the photocatalysts.

$$ \begin{gathered} {\text{MoS}}_{{2}} /{\text{ZnFe}}_{{2}} {\text{O}}_{{4}} + {\text{ h}}\upsilon \to {\text{MoS}}_{{2}} /{\text{ZnFe}}_{{2}} {\text{O}}_{{4}} ({\text{e}}^{ - } + {\text{h}}^{ + } ) \hfill \\ {\text{O}}_{{2}} + {\text{ e}}^{ - } \to \cdot{\text{O}}_{{2}}^{ - } \hfill \\ \cdot{\text{O}}_{{2}}^{ - } + {\text{ h}}^{ + } + {\text{Tetracycline}} \to {\text{OX}}.{\text{ Prod}} \hfill \\ \end{gathered} $$

4 Conclusion

The study selected a simple hydrothermal method to synthesize the MoS2/ZnFe2O4 photocatalysts. The physical and chemical properties of the photocatalysts were characterized by various instruments. The photocatalysts have good visible light response ability and magnetic separation recovery capacity, exhibiting higher photocatalytic performance in the degradation of TC. The MoS2/ZnFe2O4 photocatalysts could be reused four times with no significant decrease in the photocatalytic activity. The reason for the high photocatalytic activity of MoS2/ZnFe2O4 photocatalysts is due to the introduction of nanosheets structure of MoS2 and the heterostructures formed by ZnFe2O4 and MoS2. Active species capturing experiments reveal that ·O2− was the main active species for the photodegradation of TC.