Статья

Sub-picosecond charge-transfer at near-zero driving force in polymer:non-fullerene acceptor blends and bilayers

Yufei ZhongDepartment of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, SwitzerlandMartina Causa’Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, SwitzerlandGareth John MooreDepartment of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, SwitzerlandPhilipp KrauspeDepartment of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, SwitzerlandBo XiaoChinese Academy of Sciences (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. ChinaFlorian GüntherInstituto de Física de São Carlos (IFSC), Universidade de São Paulo (USP), Av. Trabalhador saocarlense, 400, CEP, 13560-970, São Carlos, BrazilJonas KublitskiDresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, GermanyRishi ShivhareDresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, GermanyJohannes BenduhnDresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, GermanyEyal Bar-OrInstitute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, GermanyS. MukherjeeMaterial Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USAKaila M. YallumDepartment of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, SwitzerlandJulien RéhaultDepartment of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, SwitzerlandStefan C. B. MannsfeldDresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, GermanyDieter NeherInstitute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, GermanyLee J. RichterMaterial Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USADean M. DeLongchampMaterial Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USAFrank OrtmannCenter for Advancing Electronics Dresden, Technische Universität Dresden, Helmholtzstr. 18, 01062, Dresden, GermanyKoen VandewalInstitute for Materials Research (IMO-IMOMEC), Hasselt University, Wetenschapspark 1, 3590, Diepenbeek, BelgiumErjun ZhouChinese Academy of Sciences (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China. [email protected]Natalie BanerjiDepartment of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland. [email protected]

2020en

ABI

Аннотация

Organic photovoltaics based on non-fullerene acceptors (NFAs) show record efficiency of 16 to 17% and increased photovoltage owing to the low driving force for interfacial charge-transfer. However, the low driving force potentially slows down charge generation, leading to a tradeoff between voltage and current. Here, we disentangle the intrinsic charge-transfer rates from morphology-dependent exciton diffusion for a series of polymer:NFA systems. Moreover, we establish the influence of the interfacial energetics on the electron and hole transfer rates separately. We demonstrate that charge-transfer timescales remain at a few hundred femtoseconds even at near-zero driving force, which is consistent with the rates predicted by Marcus theory in the normal region, at moderate electronic coupling and at low re-organization energy. Thus, in the design of highly efficient devices, the energy offset at the donor:acceptor interface can be minimized without jeopardizing the charge-transfer rate and without concerns about a current-voltage tradeoff.

Перевод пока недоступен

Идентификаторы

DOI: 10.1038/s41467-020-14549-w

Цитирования и источники

Цитирований: 2Использованных источников: 0

Показатели — AkademScholar