A bilateral cyano molecule serving as an effective additive enables high-efficiency and stable perovskite solar cells  

作　　者：Pengyun Liu Huimin Xiang Wei Wang Ran Ran Wei Zhou Zongping Shao 

机构地区：[1]WA School of Mines:Minerals,Energy and Chemical Engineering(WASM-MECE),Curtin University,Perth,WA 6845,Australia [2]College of Chemical Engineering,State Key Laboratory of Materials-Oriented Chemical Engineering,Nanjing Tech University,Nanjing 210009,Jiangsu,China

出　　处：《Journal of Energy Chemistry》2021年第11期243-251,I0006,共10页能源化学（英文版）

基　　金：This work was supported by the Australian Research Council Discovery Projects(DPI 50104365 and DPI 60104835);the National Natural Science Foundation of China(No.21908106 and 21878158);the Jiangsu Natural Science Foundation(No.BK20190682);the Program forjiangsu Specially-Appointed Professors,the Funding from State Key Laboratory of Materials-Oriented Chemical Engineering(No.ZK201808);a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).

摘　　要：The existence of defects in perovskite films is a major obstacle that prevents perovskite solar cells (PSCs) from high efficiency and long-term stability. A variety of additives have been introduced into perovskite films for reducing the number of defects. Lewis base-based additive engineering has been considered as an effective way to eliminate defects, especially the defects caused by the uncoordinated Pb^(2+). In this work, for the first time, a bilateral cyano molecule (succinonitrile, SN) which is a commonly used plasticizer in solid electrolyte of solid-state lithium batteries was selected as an additive to modify organic–inorganic hybrid perovskite films in PSCs. SN is featured with two cyano groups (–C≡N) distributing at both terminals of the carbon chain, providing two cross-linking points to interact with perovskites crystals via coordinating with uncoordinated Pb2+ and forming hydrogen bonds with –NH2 groups in perovskite. It was found that the addition of SN into perovskite precursor solution could effectively reduce defects, particularly inhibit the appearance of Pb0 and thus suppress trap-assisted nonradiative charge carrier recombination. As a result, the efficiency of CH_(3)NH_(3)PbI_(3)(Cl) (MAPbI_(3)(Cl))-based PSCs was improved from 18.4% to 20._(3)% with enhanced long-term stability at N2 and humid air atmosphere. This work provides a facile and effective strategy to enhance the PCE and stability of PSCs simultaneously, facilitating the commercialization of PSCs.

关 键 词：Perovskite solar cells Succinonitrile additive Cyano groups Defect engineering Suppressed charge recombination 

分 类 号：TM914.4[电气工程—电力电子与电力传动] TB383.2[一般工业技术—材料科学与工程]