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arXiv · 1911.13041

Intrinsically distinct hole and electron transport in conjugated polymers controlled by intra and intermolecular interactions

Giuseppina Pace·Ilaria Bargigia·Yong-Young Noh·Carlos Silva·Mario Caironi
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Abstract

It is still a matter of controversy whether the relative difference in hole and electron transport in solution-processed organic semiconductors is either due to intrinsic properties linked to chemical and solid-state structure or to extrinsic factors, as device architecture. We here isolate the intrinsic factors affecting either electron or hole transport within the same film microstructure of a model copolymer semiconductor. Relatively, holes predominantly bleach inter-chain interactions with H-type electronic coupling character, while electrons' relaxation more strongly involves intra-chain interactions with J-type character. Holes and electrons mobility correlates with the presence of a charge transfer state, while their ratio is a function of the relative content of intra- and inter-molecular interactions. Such fundamental observation, revealing the specific role of the ground-state intra- and inter-molecular coupling in selectively assisting charge transport, allows predicting a more favorable hole or electron transport already from screening the polymer film ground state optical properties.

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Giuseppina Pace, Ilaria Bargigia, Yong-Young Noh, Carlos Silva, Mario Caironi. 2019-11-29. Intrinsically distinct hole and electron transport in conjugated polymers controlled by intra and intermolecular interactions. https://doi.org/10.1038/s41467-019-13155-9

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