Introducing alkoxy groups as outer side chains and substituents ofπ-bridges obtains high-performance medium-bandgap polymerized small molecule acceptors  

作　　者：Yufei Gong Tianwei Zou Xiaojun Li Hongmei Zhuo Shucheng Qin Guangpei Sun Lei Meng Yongfang Li 

机构地区：[1]Beijing National Laboratory for Molecular Sciences,CAS Key Laboratory of Organic Solids,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China [2]School of Chemical Science,University of Chinese Academy of Sciences,Beijing 100049,China [3]Laboratory of Advanced Optoelectronic Materials,College of Chemistry,Chemical Engineering and Materials Science,Soochow University,Suzhou 215123,China

出　　处：《Science China Chemistry》2023年第10期2912-2920,共9页中国科学（化学英文版）

基　　金：supported by the National Key Research and Development Program of China(2019YFA0705900);the Ministry of Science and Technology,the National Natural Science Foundation of China(51820105003,21734008,52203248,61904181,52173188);the Key Research Program of the Chinese Academy of Sciences(XDPB13);the Basic and Applied Basic Research Major Program of Guangdong Province(2019B030302007)。

摘　　要：The medium-bandgap polymerized small molecule acceptors(PSMAs)have broad application scenarios.However,the effort in the molecular design of the high-performance medium-bandgap PSMAs is limited.In this article,we introduce alkoxy groups as outer side chains and as substituents of the thiopheneπ-bridges of the high-performance PSMA PY-IT to synthesize a mediumbandgap PSMA PO-TO.Due to the fact that the non-covalent interaction between the alkoxy groups and the terminal groups of the small molecule acceptor(SMA)unit can weaken the intramolecular charge transfer(ICT)effect,the bandgap of PO-TO is enlarged and its absorption is blue-shifted compared with PY-IT,while the absorbance of PO-TO solution and film is enhanced significantly compared with that of PY-IT.When blended PO-TO with the polymer donor PBQx-TF,the corresponding all-polymer solar cells(all-PSCs)exhibit an open-circuit voltage(V_(oc))exceeding 1.04 V with a power conversion efficiency(PCE)of 13.75%.Furthermore,PO-TO was used as the third component to fabricate ternary all-PSCs with PBQx-TF as the polymer donor and PY-IT as the main polymer acceptor,and the ternary all-PSCs based on PBQx-TF:PY-IT:PO-TO(1:1:0.2,w/w/w)demonstrated a high PCE of 17.71%with simultaneously improved V_(oc)of 0.940 V,short-circuit current density(J_(sc))of 24.60 m A cm^(-2)and fill factor(FF)of76.81%.In comparison,the binary all-PSCs based on PBQx-TF:PY-IT showed a PCE of 16.77%.This result indicates that introducing alkoxy groups is a promising strategy for synthesizing high-performance medium-bandgap PSMAs.

关 键 词：polymerized small molecule acceptors medium bandgap PSMAs all-polymer solar cells ternary all-PSCs alkoxy substituents 

分 类 号：TM914.4[电气工程—电力电子与电力传动] O631[理学—高分子化学]