Open AccessReducing V OC loss via structure compatible and high lowest unoccupied molecular orbital nonfullerene acceptors for over 17%‐efficiency ternary organic photovoltaics
Author(s) -
Yan Cenqi,
Ma Ruijie,
Cai Guilong,
Liu Tao,
Zhu Jingshuai,
Wang Jiayu,
Li Yuhao,
Huang Jiaming,
Luo Zhenghui,
Xiao Yiqun,
Lu Xinhui,
Yang Tao,
Zhan Xiaowei,
Yan He,
Li Gang
Publication year - 2020
Publication title -
ecomat
Language(s) - English
Resource type - Journals
ISSN - 2567-3173
DOI - 10.1002/eom2.12061
Subject(s) - ternary operation , homo/lumo , organic solar cell , crystallinity , materials science , active layer , photovoltaics , open circuit voltage , optoelectronics , photovoltaic system , nanotechnology , layer (electronics) , chemistry , polymer , voltage , molecule , organic chemistry , physics , composite material , electrical engineering , computer science , engineering , programming language , thin film transistor , quantum mechanics
The ternary strategy is effectual to attain high‐performance organic photovoltaics (OPVs). Herein, device processing and performance of PM6:Y6:IT‐4F OPVs is improved, and ITIC‐Th with high‐lying lowest unoccupied molecular orbital is incorporated into PM6: Y6 blend. The PM6:Y6: ITIC‐Th device afforded an excellent PCE of 17.2%, surpassing PM6: Y6 device, and becoming one of the highest PCE. The resulting ITIC‐Th‐based ternary OSCs demonstrated low energy loss ( E loss ) of 0.53 to 0.54 eV, as compared to their binary counterparts with either high open‐circuit voltage ( V OC ) but large E loss , or less E loss but low V OC . The incorporation of ITIC‐Th and IT‐4F balanced the charge mobilities, and thereby retained and improved fill factors. Increased crystalline coherence length and smaller d‐spacing of π ‐ π peaks are also observed in ternary blends, indicating enhanced crystallinity and thus improved active‐layer morphology. These findings demonstrate the feasibility of exploring the exciting pool of nonfullerene acceptors to pursue new breakthroughs of OPVs.