摘要：Two novel organic small molecule donor materials(FLU),TDPP and(DFLU)_(2)TDPP based on diketopyrrolopyrrole-fluorene were designed and synthesized *** D-D-π-A-π-D-D type molecule(DFLU)_(2)TDPP was constructed based on the D-π-A-π-D type molecule(FLU)_(2)TDPP by a backbone extension *** optical absorption,electrochemistry and photovoltaic properties of the two novel materials were investigated in ***(FLU)_(2)TDPP and(DFLU)_(2)TDPP show narrow energy gaps of1.71 and 1.64 eV,*** to(FLU)_(2)TDPP,the photovoltaic device based on(DFLU)_(2)TDPP/PC_(71)BM exhibited a higher power conversion efficiency of 2.27%due to its excellent optical absorption,narrow band gap and balanced carrier *** study indicates that skeleton extension strategy is an effective strategy to broaden the molecular absorption range and improve device performance.

摘要：通过Suzuki偶联反应成功合成了两种新型的小分子光伏给体材料BT-1和BT-2,其以5,6-正辛氧基苯并噻二唑为中心吸电子单元,分别以9-苯基-9H-咔唑或N,N-二甲基苯胺为末端给电子单元,以联二噻吩或噻吩为桥键.利用核磁和高分辨质谱对其进行了结构表征.通过紫外-可见吸收光谱和电化学循环伏安法及密度泛函和含时密度泛函理论对其性质进行了研究.结果表明,BT-1和BT-2在常规有机溶剂中具有良好的溶解性;具有较宽的紫外-可见光谱吸收范围;具有与受体材料PC61BM相匹配的HOMO和LUMO能级.其中,弱给电子单元9-苯基-9H-咔唑的引入有效降低了BT-1的HOMO能级,有助于获得较高的开路电压;强给电子单元N,N-二甲基苯胺的引入降低了BT-2的禁带宽度,有利于获得较大的短路电流.