Understanding of the Nearly Linear Tunable Open-Circuit Voltages in Ternary Organic Solar Cells Based on Two Non-fullerene Acceptors

• Published in: The journal of physical chemistry letters Vol. 12; no. 1; pp. 151 - 156
• Main Authors: Jia, Ziyan, Chen, Zeng, Chen, Xu, Bai, Lizhong, Zhu, Haiming, Yang, Yang Michael
• Format: Journal Article
• Language: English
• Published: United States 14.01.2021
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/acs.jpclett.0c03177

Although the power conversion efficiencies (PCEs) of the state-of-the-art organic solar cells (OSCs) have exceeded 17%, the organic photovoltaic devices still suffer from considerable voltage losses compared with the inorganic or perovskite solar cells. Therefore, the optimization of open-circuit voltage ( ) is of great significance for the improvement of the photovoltaic performance of OSCs. The origins of have been well-established in the binary system; however, the understanding of in non-fullerene acceptor (NFA)-based ternary OSCs is still lacking. Herein, we have developed a series of ternary organic photovoltaic devices, exhibiting nearly linear increased as the increase of ITIC third content. We found that both the effective charge-transfer (CT) states and the nonradiative recombination losses of the bulk-heterojunction (BHJ) are altered in the ternary blends, and they collectively contribute to the tunable . Our results provide a perspective for understanding the origin of in NFA-based ternary OSCs.