Conjugation expansion strategy enables highly stable all-polymer solar cells

查看全文 作　　者：Dingding [1,2,4]Qiu;Yanan [1,2]Shi;Yi [1,3]Li;Jianqi [1]Zhang;Kun [1,2]Lu;Zhixiang [1,2]Wei 机构地区：[1]CAS Key Laboratory of Nanosystem and Hierarchical Fabrication,CAS Center for Excellence in Nanoscience,National Center for Nanoscience and Technology,Beijing 100190,China;[2]University of Chinese Academy of Sciences,Beijing 100049,China;[3]Department of Chemistry,Molecular Dynamic Chemistry Center,Tianjin Key Laboratory of Molecular Optoelectronic Sciences,School of Science,Tianjin University,Tianjin 300354,China;[4]Sino-Danish Center for Education and Research,Sino-Danish College,University of Chinese Academy of Sciences,Beijing 100049,China 出　　处：《Chinese Chemical Letters》索引2023年第34卷第8期,共5页 基　　金：We acknowledge financial support provided by the National Natural Science Foundation of China(Nos.21822503 and 51973043);the and the CAS-CSIRO Joint Project of Chinese Academy of Sciences(No.121E32KYSB20190021). 摘　　要：The stability issue is one of the key factors hindering the commercial application of organic solar cells.All-polymer organic solar cell is one of the effective ways to solve the stability problem.In this work,we designed and synthesized two polymer donor materials PBDT and PDTBDT with different conjugation ranges,and demonstrated for the first time that extending the conjugation range of donor materials in all polymer solar cells can significantly improve device efficiency and stability.The experimental results of materials and devices show that PDTBDT with a larger conjugation range has stronger crystallinity and a more planar structure,which endows the active layer in its corresponding device with higher exciton dissociation probability,lower carrier recombination probability,more balanced charge transport properties and more favorable film morphology.As a result,the PDTBDT:PYF-T-o devices display an outstanding PCE of 13.38%,which is much higher than PBDT with smaller conjugation range based devices.Moreover,the PDTBDT:PYF-T-o device retains 0.86 of the initial PCE after over 500 h in the air atmosphere,exhibiting significantly improved stability.The improved stability is attributed to the enhanced moisture and air tolerance of active layer film thanks to the strong crystallinity of the donor material.These results demonstrate that the conjugation expansion strategy is one of the effective ways to obtain efficient and stable all-polymer organic solar cells. 关 键 词：Polymer donor Conjugation expansion All-polymer organic solar cells Stability CRYSTALLINITY