Effects of processing additives in non-fullerene organic bulk heterojunction solar cells with efficiency >11%

作     者：Shenkun Xie Jianqiu Wang Rong Wang Dongyang Zhang Huiqiong Zhou Yuan Zhang Defeng Zhou 

作者机构：School of Chemistry and Life Science Changchun University of Technology HEEGER Beijing Research & Development Center School of Chemistry Beihang University CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology 

出 版 物：《Chinese Chemical Letters》 (中国化学快报（英文版）)

年 卷 期：2019年第30卷第1期

页      面：217-221页

核心收录：

学科分类：07[理学] 0703[理学-化学] 

基　　金：the National Natural Science Foundation of China (No. 21471022) the National Natural Science Foundation of China (No. 21674006) the Chinese Academy of Science (100 Top Young Scientists Program, No. QYZDB-SSW-SLH033) the National Key Research and Development Program of China (No. 2017YFA0206600) 

主　　题：Organic solar cell Solvent additive Morphology Recombination Non-fullerene 

摘      要：Here we investigate processing additive-dependent photovoltaic performance and charge recombination in organic bulk heterojunction(BHJ) solar cells based on a polymeric donor of PBDB-T blended with a non-fullerene acceptor m-ITIC. We find that PBDB-T:m-ITIC solar cells exhibit good compatibilities with the utilized additives(DIO, CN, DPE, and NMP) in optimal conditions, can have a high charge dissociation probability approaching 100%(with DIO), leading to ultimate efficiency 11%. Regardless of additives, we observe a dominant 1 st order monomolecular recombination with insignificant bi-molecular recombination or space-charge effects in these solar cells. Despite of impressive power conversion efficiency(PCE), it is of surprise that Shockley-Read-Hall recombination is identified to play a role in device operation. Thus, it points to the necessity to mitigate the influences of traps to further boost the efficiency in non-fullerene based organic solar cells.