New low band gap 2-(4-(trifluoromethyl)phenyl)-1H-benzo[d]imidazole and benzo[1,2-c;4,5-c′]bis[1,2,5]thiadiazole based conjugated polymers for organic photovoltaics
作者:M. G. Murali、Arun D. Rao、Praveen C. Ramamurthy
DOI:10.1039/c4ra08214a
日期:——
Two new low band gap D–A structured conjugated polymers, PBDTTBI and PBDTBBT, based on 2-(4-(trifluoromethyl)phenyl)-1H-benzo[d]imidazole and benzo[1,2-c;4,5-c′]bis[1,2,5]thiadiazole acceptor units with benzo[1,2-b;3,4-b′]dithiophene as a donor unit have been designed and synthesized via a Stille coupling reaction. The incorporation of the benzo[1,2-c;4,5-c′]bis[1,2,5]thiadiazole unit into PBDTBBT
两个新的低带隙d-结构化共轭聚合物,PBDTTBI和PBDTBBT,基于2-(4-(三氟甲基)苯基)-1 ħ -苯并[ d ]咪唑基和苯并[1,2 Ç ; 4,5-通过Stille偶联反应设计并合成了以苯并[1,2- b ; 3,4- b ']二噻吩为供体的c '] bis [1,2,5]噻二唑受体单元。将苯并[1,2- c ; 4,5- c ']双[1,2,5]噻二唑单元并入PBDTBBT显着改变了聚合物的光学和电化学性能。对于PBDTTBI和PBDTBBT,从开始吸收边缘估计的光学带隙分别为〜1.88eV和〜1.1eV。观察到PBDTBBT表现出更强的HOMO能级(-4.06 eV),且具有强大的分子内电荷转移相互作用。使用ITO / PEDOT:PSS / PBDTBBT:PC 71 BM / Al构造的块状异质结太阳能电池表现出0.67%的最佳功率转换效率,短路电流密度为4.9 mA