Chlorination of benzyl group on the terminal unit of A_(2)-A_1-D-A_1-A_(2) type nonfullerene acceptor for high-voltage organic solar cells  

作　　者：Jinge Zhu Ailing Tang Leyi Tang Peiqing Cong Chao Li Qing Guo Zongtao Wang Xiaoru Xu Jiang Wu Erjun Zhou 

机构地区：[1]School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China [2]National Center for Nanoscience and Technology,Beijing 100190,China [3]Zhongyuan Critical Metals Laboratory,Zhengzhou University,Zhengzhou 450001,China [4]Henan Institute of Advanced Technology,Zhengzhou University,Zhengzhou 450003,China

出　　处：《Chinese Chemical Letters》2025年第1期312-317,共6页中国化学快报(英文版)

基　　金：support from the National Natural Science Foundation of China(Nos.52373176,52073067)。

摘　　要：Benzotriazole(BTA)-based A_(2)-A_1-D-A_1-A_(2)type wide-bandgap(WBG)non-fullerene acceptors(NFAs)have shown promising potential in indoor photovoltaic,and in-depth investigation of their structure-property relationship is of great significance.Herein,we explored the chlorination effect of the side chain on the terminals.We introduced Cl atoms into the benzyl side chains in parent BTA5 to synthesize two NFAs,BTA5-Cl with mono-chlorinated benzyl groups and BTA5-2Cl containing bi-chlorinated benzyl groups.We chose D18-Cl with deep-energy levels and strong crystallinity to pair with these three acceptors,affording high photovoltage and photocurrent.With the stepwise chlorination,the open-circuit voltage(V_(OC))values decrease from 1.28,1.22,to 1.20 V,while the corresponding power conversion efficiencies(PCEs)improve from 5.07%,9.15%,to 10.96%.Compared with BTA5-based OSCs,introducing Cl atoms downshifts the energy levels and slightly increases the non-radiative energy loss(0.14<0.17<0.19 e V),resulting in a sequential decrease in VO C.However,more chlorine atom replacements produce more effective exciton dissociation,higher charge transfer,and balanced carrier mobility in the blend films,ultimately achieving better PCEs.This work indicates that chlorination of the benzyl group on the terminals can improve the device's performance,implying good application potential in indoor photovoltaics.

关 键 词：High open-circuit voltage BENZOTRIAZOLE Non-fullerene acceptor Terminal engineering CHLORINATION 

分 类 号：TM914.4[电气工程—电力电子与电力传动] TB322[一般工业技术—材料科学与工程]