n-Octyl substituted quinoxaline-based polymer donor enabling all-polymer solar cell with efficiency over 17%  

辛基取代喹喔啉聚合物给体使全聚合物有机太阳能电池的效率超过17%

作　　者：Ke Hu Can Zhu Shucheng Qin Wenbin Lai Jiaqi Du Lei Meng Zhanjun Zhang Yongfang Li 胡克;朱灿;秦书诚;赖文彬;杜家琦;孟磊;张占军;李永舫(School of Chemical Science,University of Chinese Academy of Sciences,Beijing 100049,China;Beijing National Laboratory for Molecular Sciences,CAS Key Laboratory of Organic Solids,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China;Laboratory of Advanced Optoelectronic Materials,Suzhou Key Laboratory of Novel Semiconductor-optoelectronics Materials and Devices,College of Chemistry,Chemical Engineering and Materials Science,Soochow University,Suzhou215123,China)

机构地区：[1]School of Chemical Science,University of Chinese Academy of Sciences,Beijing 100049,China [2]Beijing National Laboratory for Molecular Sciences,CAS Key Laboratory of Organic Solids,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China [3]Laboratory of Advanced Optoelectronic Materials,Suzhou Key Laboratory of Novel Semiconductor-optoelectronics Materials and Devices,College of Chemistry,Chemical Engineering and Materials Science,Soochow University,Suzhou215123,China

出　　处：《Science Bulletin》2022年第20期2096-2102,M0004,共8页科学通报（英文版）

基　　金：supported by the National Key Research and Development Program of China(2019YFA0705900);the National Natural Science Foundation of China(51820105003,21734008,61904181,and 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：Recently, the power conversion efficiencies(PCEs) of all-polymer solar cells(all-PSCs) have increased rapidly. To further increase the PCE of all-PSCs, it is necessary to create new donor polymers matching the polymer acceptors. In this paper, we synthesize a new quinoxaline-based polymer donor PBQ8 with n-octyl side chain on the quinoxaline unit, which possesses the same skeleton structure to the previously reported PBQ5(with isooctyl side chain). The effects of alkyl side chains on the physicochemical properties of the polymer donor were investigated. In comparison with PBQ5, PBQ8 exhibits stronger intermolecular interactions and better molecular packing. When blending with polymer acceptor PY-IT, the PBQ8:PY-IT based devices demonstrated a higher PCE value of 17.04%, which is one of the highest PCEs occurred in the all-PSCs. And the PBQ5:PY-IT(PCE 15.56%, Voc0.907 V, FF 69.72%, and Jsc24.60 m A cm^(-2)) is much lower. The PBQ8:PY-IT blend displayed more efficient exciton dissociation, better molecular stacking properties, preferable phase separation and higher mobility. These indicate that as an effective method, side chain engineering can improve the efficiency of the all-PSCs.本文设计并合成了一种新型喹喔啉类聚合物给体PBQ8,其在喹喔啉单元上具有正辛基侧链,与先前报道的PBQ5(异辛基侧链)具有相同的聚合物骨架结构.与PBQ5相比,PBQ8表现出更强的分子间相互作用和更好的分子堆积.当其与聚合物受体PY-IT共混时,基于PBQ8:PY-IT的全聚合物太阳能电池表现出远高于PBQ5:PY-IT器件效率,其能量转化效率为17.04%,这是目前全聚合物太阳能电池中的最高效率之一.结果表明,聚合物给体的侧链工程是进一步提高全聚合物太阳能电池光伏性能的有效途径.

关 键 词：All-polymer solar cells Side-chain engineering Difluoroquinoxaline A-unit Polymerized small molecule acceptors 

分 类 号：TB34[一般工业技术—材料科学与工程] TM914.4[电气工程—电力电子与电力传动]