Abstract
The determination of molecular conformation of oligomeric acceptors (OAs) and their impact on molecular packing are crucial for understanding the photovoltaic performance of resulting polymer solar cells (PSCs) but have not been well studied yet. Herein, we synthesized two dimeric acceptor materials, DIBP3F-Se and DIBP3F-S, which bridged two segments of Y6-derivatives by selenophene and thiophene, respectively. Theoretical simulation and experimental 1D and 2D NMR spectroscopic studies prove that both dimers exhibit O-shape conformation other than S- or U-shape counter-ones. Notably, this O-shaped conformation is likely governed by a distinctive "conformational lock" mechanism, arising from the intensified intramolecular π-π interaction between the two terminal groups of the dimers. PSCs based on DIBP3F-Se deliver a maximum efficiency of 18.09%, outperforming DIBP3F-S-based cells (16.11%) and ranking among the highest efficiencies for OA-based PSCs. This work demonstrates a facile method to obtain OA conformations and highlights the potential of dimeric acceptors for high-performance PSCs.
Original language | English (US) |
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Journal | Angewandte Chemie International Edition |
DOIs | |
State | Published - Jun 28 2023 |
Bibliographical note
KAUST Repository Item: Exported on 2023-07-07Acknowledged KAUST grant number(s): OSR-2018-CARF/CCF-3079, OSR-2019-CRG8-4095.3
Acknowledgements: We thank the Swedish Research Council (2016-06146, 2019-04683, 2020-05233), Swedish Research Council Formas, Knut and Alice Wallenberg Foundation (2017.0186, 2016.0059), Swedish Energy Agency (Grant number: P2021-90067) and STandUP for Energy collaboration. Computations/simulations were performed at Chalmers e-Commons (C3SE) and Swedish National Infrastructure for Computing (SNIC) at the National Supercomputer Centre (NSC) at Linköping University. J. W. acknowledges the support from the Chinese Scholarship Council. T.D.A., Z.H., C. C., X.C., F.H.I.,F.L., acknowledge support by the KAUST Office of Sponsored Research (OSR) under Awards No: OSR-2018-CARF/CCF-3079 and No: OSR-2019-CRG8-4095.3. H.Y.W. acknowledges the support from the National Research Foundation of Korea (2019R1A6A1A11044070). Support from Sino-Danish Center (SDC) for Education and Research is fully acknowledged. The 2D NMR measurements were performed at the Swedish NMR Center, in Gothenburg, Sweden. Grateful for the discussion with Prof. Reinhard Wimmer from Aalborg University on a conformational determination.
ASJC Scopus subject areas
- General Chemistry
- Catalysis