The Potential Game-Changer:A Concept-to-Proof Study on D:A Heterojunction-Free Organic Photovoltaics  

作　　者：Lijian Zuo Sae Byeok Jo Xueliang Shi Francis Lin Alex Jen 

机构地区：[1]State Key Laboratory of Silicon and Advanced Semiconductor Materials,MOE Key Laboratory of Macromolecular Synthesis and Functionalization,Department of Polymer Science and Engineering,Zhejiang University,Hangzhou,Zhejiang,310058 China [2]Department of Materials Science and Engineering,University of Washington,Seattle,WA,USA [3]School of Chemical Engineering,Sungkyunkwan University (SKKU),Suwon,16419 Republic of Korea [4]School of Chemistry and Molecular Engineering,East China Normal University,Shanghai,200062 China [5]Department of Materials Science and Engineering,City University of Hong Kong,Kowloon,Hong Kong,China [6]Department of Chemistry,City University of Hong Kong,Kowloon,Hong Kong,China [7]Hong Kong Institute for Clean Energy,Hong Kong,China

出　　处：《Chinese Journal of Chemistry》2024年第3期252-258,共7页中国化学（英文版）

基　　金：supported by the National Key Research and Development Program of China(No.2022YFB4200600);the National Natural Science Foundation of China(Nos.52173185 and 52127806);the Fundamental Research Funds for the Central Universities(Nos.226-2022-00133 and 226-2022-00209);L.Z.thanks the research start-up fund from Zhejiang University.

摘　　要：Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.

关 键 词：Organic solar cells Spontaneous charge generation Ambipolar charge transport Charge recombination Perovskite-like organic semiconductor Schottky-junction structure Single component 

分 类 号：O63[理学—高分子化学]