Abstract
The performance of conjugated polymer (CP)-based electronic devices relies on optimal charge carrier mobilities, which are determined by monomeric architecture, degree of polymerization, chain conformation, and the nano- and mesoscale morphologies. With regard to the latter, we discuss two effects that have received limited attention in the literature, yet important for device performance optimization: (1) the role of morphological disorder and of CP/substrate interactions on the in-plane and out-of-plane carrier transport in CPs; (2) the impact of morphological disorder on charge transfer at the CP/substrate interface. The emergence of film thickness-dependent carrier mobilities, varying over two orders of magnitude within a length scale of 200 nm, and band-bending phenomena, extending tens of nanometers within the CP, are associated with these effects. These findings suggest areas for further research in order to enable widespread applications of next-generation CP-based devices.
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Acknowledgments
This work was authored in part by Alliance for Sustainable Energy, LLC, the managed and operator of the National Renewable energy Laboratory for the U.S. Department of Energy (DOE) under contract No. DE-AC36-08G028308 (PFG). The views expressed in this article do not necessarily represent the views of the DOE or the U.S. Government.
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Research presented here was enabled in part by support from the Department of Energy, Energy Frontier Research Center, Award No. DE-SC0000957.
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Dong, B.X., Wenderott, J.K. & Green, P.F. Charge carrier transport in thin conjugated polymer films: influence of morphology and polymer/substrate interactions. Colloid Polym Sci 299, 439–456 (2021). https://doi.org/10.1007/s00396-020-04725-1
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DOI: https://doi.org/10.1007/s00396-020-04725-1