Achieving 19.2% High‐Efficiency Ternary Organic Solar Cells Through Novel Sequential Processing Technique With Hydrocarbon Solvent

• DOI: 10.1002/sus2.70008
• Publication Date: 2025-04-09T03:49:56Z
• Authors: Liangxiang Zhu; Chuanlin Gao; Chaoyue Zhao; Guoping Zhang; Kangbo Sun; Shenbo Zhu; Yajie Wang; Lihong Wang; Peng You; Chen Xie; Qing Bai; Huawei Hu; Mingxia Qiu; Bin He; Yufei Wang; Shunpu Li; Guangye Zhang

ABSTRACT In organic solar cells (OSCs), typical methods for fabricating the ternary active layer are blend‐casting (BC) or two‐step sequential processing (SqP‐2T), where all three at least two components blended together, which affect crystallization/aggregation behavior of each other during solid‐film formation. Herein, we introduce first time a novel three‐step method, termed SqP‐3T, utilizes hydrocarbon solvents to prepare high‐quality layers. Compared SqP‐2T and BC techniques, SqP‐3T yields an with higher acceptor ratio on its upper surface exhibits longer crystal coherence length in out‐of‐plane direction (21.42 Å). These characteristics enhance charge transport collection. Additionally, devices demonstrate nearly twofold increase transient photovoltage decay constant (up 2.82 µs) that is related carrier lifetime certain extent, leading reduced recombination losses. Consequently, device achieves high fill factor (75.67%) short‐circuit current density (27.35 mA/cm 2 ), contributing power conversion efficiency 19.2%. results highlight potential multi‐step deposition process production multicomponent OSCs, could be adopted by more material systems future.