In this work, a novel ionic liquid (IL) is demonstrated as an interface modification layer in photovoltaic devices to improve power conversion efficiency (PCE) in inverted organic solar cell (i-OSCs). As a result, the PTB7-Th:PC71BM-based devices using ZnO/IL as ETL layer exhibited over 15% PCE increment with enhanced short-circuit current density (Jsc) and fill factor (FF), compared with pure ZnO appliance in ETL. The ZnO layer modified with IL has a better electron extraction capability and lower work function, both of which contribute to better device performance.
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This work was supported by the National Natural Science Foundation of China (51803063, 51561135014), Guangdong Basic and Applied Basic Research Foundation (2019B151502060), and Guangdong Natural Science Foundation (2018A030313257), Program for Chang Jiang Scholars and Innovative Research Teams in Universities (No. IRT_17R40), leading talents of Guangdong province Program (No. 00201504), Science and Technology Program of Guangzhou (No. 2019050001), Guangdong Provincial Key Laboratory of Optical Information Materials and Technology (Grant No. 2017B030301007), MOE International Laboratory for Optical Information Technologies, and 111 Project.
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Zhang, X., Cui, M., Nian, L. et al. Ionic liquid-modified ZnO-based electron transport layer for inverted organic solar cells. J Mater Sci: Mater Electron (2020). https://doi.org/10.1007/s10854-020-03818-5