Abstract
Conjugated polymers and molecular semiconductors are emerging as a viable semiconductor technology in industries such as displays, electronics, renewable energy, sensing and healthcare. A key enabling factor has been significant scientific progress in improving their charge transport properties and carrier mobilities, which has been made possible by a better understanding of the molecular structure–property relationships and the underpinning charge transport physics. Here we aim to present a coherent review of how we understand charge transport in these high-mobility van der Waals bonded semiconductors. Specific questions of interest include estimates for intrinsic limits to the carrier mobilities that might ultimately be achievable; a discussion of the coupling between charge and structural dynamics; the importance of molecular conformations and mesoscale structural features; how the transport physics of conjugated polymers and small molecule semiconductors are related; and how the incorporation of counterions in doped films—as used, for example, in bioelectronics and thermoelectric devices—affects the electronic structure and charge transport properties.
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Acknowledgements
S.F. acknowledges support by the German Research Foundation DFG (grant DR228/48-1). M.N. thanks the European Commission for a Marie Skłodowska-Curie Fellowship. A.S. acknowledges financial support from the National Science Foundation, Division of Materials Research, award 1808401. G.S. acknowledges postdoctoral fellowship support from the Leverhulme Trust (Early Career Fellowship supported by the Isaac Newton Trust). H.S. thanks the Engineering and Physical Sciences Research Council (EPSRC programme grant EP/M005143/1) and the European Research Council (ERC) (Synergy grant SC2 610115) for funding.
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Fratini, S., Nikolka, M., Salleo, A. et al. Charge transport in high-mobility conjugated polymers and molecular semiconductors. Nat. Mater. 19, 491–502 (2020). https://doi.org/10.1038/s41563-020-0647-2
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DOI: https://doi.org/10.1038/s41563-020-0647-2
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