Two p-type small molecules BDTT-TR and TBFT-TR with benzo[1,2-b′:4,5-b′]dithiophene(BDT)and thieno[2,3-f]benzofuran(TBF)as central core units are synthesized and used as donors in all-small-molecule organic solar ce...Two p-type small molecules BDTT-TR and TBFT-TR with benzo[1,2-b′:4,5-b′]dithiophene(BDT)and thieno[2,3-f]benzofuran(TBF)as central core units are synthesized and used as donors in all-small-molecule organic solar cells(all-SMOSCs)with a narrow-bandgap small molecule Y6(2,2′-((2 Z,2′Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3’′:4’,5′]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1 H-indene-2,1-diylidene))dimalononitrile)as the acceptor.In comparison to BDTT-TR with centrosymmetric BDT as the central unit,TBFT-TR with asymmetric TBF as the central unit shows red-shifted absorption,higher charge-carrier mobility and better charge pathway in blend films.The power conversion efficiency(PCE)of the all-SMOSCs based on TBFT-TR:Y6 reaches 14.03%with a higher short-circuit current density of 24.59 m A cm-2 and a higher fill factor of72.78%compared to the BDTT-TR:Y6 system.The PCE of 14.03%is among the top efficiencies of all-SMOSCs reported in the literature to date.展开更多
基金the National Natural Science Foundation of China(21702154,51773157)the Fundamental Research Funds for the Central Universitiesthe Opening Project of Key Laboratory of Materials Processing and Mold and Beijing National Laboratory for Molecular Sciences(BNLMS201905)。
文摘Two p-type small molecules BDTT-TR and TBFT-TR with benzo[1,2-b′:4,5-b′]dithiophene(BDT)and thieno[2,3-f]benzofuran(TBF)as central core units are synthesized and used as donors in all-small-molecule organic solar cells(all-SMOSCs)with a narrow-bandgap small molecule Y6(2,2′-((2 Z,2′Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3’′:4’,5′]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1 H-indene-2,1-diylidene))dimalononitrile)as the acceptor.In comparison to BDTT-TR with centrosymmetric BDT as the central unit,TBFT-TR with asymmetric TBF as the central unit shows red-shifted absorption,higher charge-carrier mobility and better charge pathway in blend films.The power conversion efficiency(PCE)of the all-SMOSCs based on TBFT-TR:Y6 reaches 14.03%with a higher short-circuit current density of 24.59 m A cm-2 and a higher fill factor of72.78%compared to the BDTT-TR:Y6 system.The PCE of 14.03%is among the top efficiencies of all-SMOSCs reported in the literature to date.
