Poor stability of spiro-OMe TAD hole transport materials(HTMs)with dopant is a major obstacle for the commercialization of perovskite solar cells(pero-SCs).Herein,we demonstrate a series of quinoxaline-based D-A copol...Poor stability of spiro-OMe TAD hole transport materials(HTMs)with dopant is a major obstacle for the commercialization of perovskite solar cells(pero-SCs).Herein,we demonstrate a series of quinoxaline-based D-A copolymers PBQ5,PBQ6 and PBQ10 as the dopant-free polymer HTMs for high performance pero-SCs.The D-A copolymers are composed of fluorothienyl benzodithiophene(BDTT)as D-unit,difluoroquinoxaline(DFQ)with different side chains as A-unit,and thiophene asπ-bridge,where the side chains on the DFQ unit are bi-alkyl for PBQ5,bi-alkyl-fluorothienyl for PBQ6,and alkoxyl for PBQ10.All the three copolymers are adopted as the dopant-free HTM in the pero-SCs.The planar n-i-p structured pero-SCs based on(FAPb I_(3))_(0.98)(MAPb Br_(3))_(0.02)with PBQ6 HTM demonstrated the high power conversion efficiency(PCE)of 22.6%with Vocof1.13 V and FF of 80.8%,which is benefitted from the suitable energy level and high hole mobility of PBQ6.The PCE of 22.6%is the highest efficiency reported in the n-i-p structured pero-SCs based on dopant-free D-A copolymer HTM.In addition,the peroSCs show significantly enhanced ambient,thermal and light-soaking stability compared with the devices with traditional spiroOMe TAD HTM.展开更多
基金supported by the National Key Research and Development Program of China(2019YFA0705900)the National Natural Science Foundation of China(51820105003,21734008,61904181)the Guangdong Major Project of Basic and Applied Basic Research(2019B030302007)。
文摘Poor stability of spiro-OMe TAD hole transport materials(HTMs)with dopant is a major obstacle for the commercialization of perovskite solar cells(pero-SCs).Herein,we demonstrate a series of quinoxaline-based D-A copolymers PBQ5,PBQ6 and PBQ10 as the dopant-free polymer HTMs for high performance pero-SCs.The D-A copolymers are composed of fluorothienyl benzodithiophene(BDTT)as D-unit,difluoroquinoxaline(DFQ)with different side chains as A-unit,and thiophene asπ-bridge,where the side chains on the DFQ unit are bi-alkyl for PBQ5,bi-alkyl-fluorothienyl for PBQ6,and alkoxyl for PBQ10.All the three copolymers are adopted as the dopant-free HTM in the pero-SCs.The planar n-i-p structured pero-SCs based on(FAPb I_(3))_(0.98)(MAPb Br_(3))_(0.02)with PBQ6 HTM demonstrated the high power conversion efficiency(PCE)of 22.6%with Vocof1.13 V and FF of 80.8%,which is benefitted from the suitable energy level and high hole mobility of PBQ6.The PCE of 22.6%is the highest efficiency reported in the n-i-p structured pero-SCs based on dopant-free D-A copolymer HTM.In addition,the peroSCs show significantly enhanced ambient,thermal and light-soaking stability compared with the devices with traditional spiroOMe TAD HTM.