Synthesis and photovoltaic performance of N-dioctylmethyl- 2,7-carbazole-alt-5,7-bis(thiophen-2-yl)-2,3-biphenylthieno[3,4-b] pyrazine copolymeric derivatives appending various donor units in phenyl moieties  

作　　者：Jianmin Li Hua Tan Fanyuan Meng Wenhong Peng Yafei Wang Yu Liu Weiguo Zhu 

机构地区：[1]Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, College of Chemistry, Xiangtan University

出　　处：《Science China Chemistry》2015年第2期301-308,共8页中国科学（化学英文版）

基　　金：supported by the major program for cultivation of the National Natural Science Foundation of China(91233112);the National Natural Science Foundation of China(21172187,50973093,51403178);the Innovation Group and Xiangtan Joint Project of the Hunan Natural Science Foundation(12JJ7002,12JJ8001);the Scientific Research Fund of Hunan Provincial Education Department(11CY023,12B123);the Open Fund of the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology,No.2014-skllmd-10);the Postgraduate Science Foundation for Innovation in Hunan Province(CX2014B257,CX2011B263)

摘　　要：A series of N-dioctylmethyl-2,7-carbazole-alt-5,7-bis（thiophen-2-yl）-2,3-biphenylthieno[3,4-b]pyrazine （PCz-3ThPz-Ph） co- polymeric derivatives appending various donor units in two phenyl rings, namely, PCz-3ThPz-PhTh, PCz-3ThPz-PhF1, PCz-3ThPz-PhCz, and PCz-3ThPz-PhTpa were synthesized and characterized. The effect of these appending donor units, e.g., thiophene （Th）, fluorene （F1）, carbazole （Cz）, and triarylamine （Tpa）, was investigated on dispersible, optical, electrochemical, and photovoltaic properties for their polymers. The copolymers of PCz-3ThPz-PhCz and PCz-3ThPz-PhTpa containing Cz or Tpa units exhibited higher short-circuit current density （Jsc） and power conversion efficiency （PCE） in their bulk heterojunction polymeric solar cells. The highest PCE of 1.66% and Jsc of 7.16 mA cm-2 were obtained in a device with the PCz-3ThPz-PhCz/PC61BM blend under AM 1.5 G irradiation （100 mW cm 2）; these values are 1.78 and 1.59 times higher than the corresponding values for the PCz-3ThPz-Ph-based device. When PC61BM was placed by PC71BM, the PCz-3ThPz-PhCz-based device displayed an enhanced PCE of 2.98% and a Jsc of 10.88 mA cm-2. This work demonstrated that appending additional hole-transporting units of Cz and Tpa into the side-chain of a polymer with a D-A backbone can significantly enhance the photovoltaic performance of their resultant polymers.A series of N-dioctylmethyl-2,7-carbazole-alt-5,7-bis(thiophen-2-yl)-2,3-biphenylthieno[3,4-b]pyrazine(PCz-3Th Pz-Ph)copolymeric derivatives appending various donor units in two phenyl rings,namely,PCz-3Th Pz-Ph Th,PCz-3Th Pz-Ph Fl,PCz-3Th Pz-Ph Cz,and PCz-3Th Pz-Ph Tpa were synthesized and characterized.The effect of these appending donor units,e.g.,thiophene(Th),fluorene(Fl),carbazole(Cz),and triarylamine(Tpa),was investigated on dispersible,optical,electrochemical,and photovoltaic properties for their polymers.The copolymers of PCz-3Th Pz-Ph Cz and PCz-3Th Pz-Ph Tpa containing Cz or Tpa units exhibited higher short-circuit current density(Jsc)and power conversion efficiency(PCE)in their bulk heterojunction polymeric solar cells.The highest PCE of 1.66%and Jsc of 7.16 m A cm 2 were obtained in a device with the PCz-3Th Pz-Ph Cz/PC61BM blend under AM 1.5 G irradiation(100 m W cm 2);these values are 1.78 and 1.59 times higher than the corresponding values for the PCz-3Th Pz-Ph-based device.When PC61BM was placed by PC71BM,the PCz-3Th Pz-Ph Cz-based device displayed an enhanced PCE of 2.98%and a Jsc of 10.88 m A cm 2.This work demonstrated that appending additional hole-transporting units of Cz and Tpa into the side-chain of a polymer with a D-A backbone can significantly enhance the photovoltaic performance of their resultant polymers.

关 键 词：conjugated polymers polymer solar cells thieno[3 4-b]pyrazine functionalization of polymers 

分 类 号：TM914.4[电气工程—电力电子与电力传动] O633.5[理学—高分子化学]