基于Cz-DPP不对称D-A结构新型有机小分子光伏材料的合成与性质

本文设计合成了一系列以咔唑(CZ)和吡咯并吡咯二酮(DPP)为基本结构单元的D-A结构的新型小分子材料,并对其进行了一系列的性能表征.合成的材料以咔唑作为给电子单元,吡咯并吡咯二酮作为吸电子单元,采用三键作为π桥,并引入4-氟苯基、4-氰基苯基和4-甲氧基苯基作为末端取代基团对材料进行修饰.其中材料CZBTDPPF和CZBTDPPO因分别具有1.85和1.79 eV的较窄带隙而分别获得了相对较高的的光电转化效率(1.97%和1.91%).由此可见,引入4-氟苯基和4-甲氧基苯基作为末端取代基团对于延长材料共轭结构、拓宽材料吸收从而实现材料光伏性能的提升具有重要的作用.

Synthesis and properties of novel organic photovoltaic materials with D-A asymmetric structure based on Cz-DPP

Four novel small molecules based on carbazole-diketopyrrolopyrrole have been designed,synthesized and characterized.The synthesized molecules have a carbazole acting as an electron donor unit(D),a diketopyrrolopyrrole acting as an electron acceptor unit(A)and a triple bond acting asπbridge.In addition,4-fluorophenyl,4-cyanophenyl and 4-methoxyphenyl act as the ending groups to modify molecules.Among them,the molecule CZBTDPPF and CZBTDPPO exhibit low band gaps of 1.85 and 1.79 eV,resulting in a relatively great PCE of 1.97%and 1.91%respectively.Above results demonstrate that,the introduction of fluorine atom and methoxy group as the ending group contributes to extend the conjugation structure,broaden the absorption range,which plays an important role in improving photovoltaic properties of materials.