Aryl amine substituted low energy gap carbazole polymers: preparation and photovoltaic properties
作者:David Mohamad、Richard G. Johnson、Dainius Janeliunas、Mindaugas Kirkus、Hunan Yi、David G. Lidzey、Ahmed Iraqi
DOI:10.1039/c0jm01335h
日期:——
The preparation of a series of donor/acceptor copolymers comprising alternating 2,7-linked 3,6-dimethyl-9-arylamino-carbazole units and 5,7-bis-(thiophen-2-yl)-2,3-diphenyl-thieno[3,4-b]pyrazine units is presented. The triarylamine substituents are attached to the carbazole repeat units either through the para- or meta-positions. The effect of the linkage position of triaryl amine substituents in this series of polymers as well as the effect of substitution of the phenyl groups at the 2,3-positions of 5,7-bis-(thiophen-2-yl)-2,3-diphenyl-thieno[3,4-b]pyrazine repeat units with alkoxy-substituents are investigated in this work. The polymers were characterized by NMR spectroscopy, UV-Vis absorption spectroscopy and fluorescence spectroscopy, and their molecular weights were estimated using gel permeation chromatography. Polymers P1–P4 absorb light up to 900 nm and have energy gaps ranging from 1.37 to 1.40 eV. Photovoltaic cells with ITO/PEDOT:PSS/P2:PC70BM(1/4, w/w)/Al showed an open circuit voltage of 0.60 V under white light illumination, power conversion efficiency of 0.67% and short circuit current of 3.6 mA cm−2.
本文介绍了一系列供体/受体共聚物的制备方法,这些共聚物由交替连接的 2,7 链 3,6 二甲基-9-芳基氨基咔唑单元和 5,7 双-(噻吩-2-基)-2,3-二苯基噻吩并[3,4-b]吡嗪单元组成。三芳基胺取代基通过对位或元位连接到咔唑重复单元上。本文研究了三芳基胺取代基在该系列聚合物中的连接位置的影响,以及用烷氧基取代 5,7-双(噻吩-2-基)-2,3-二苯基噻吩并[3,4-b]吡嗪重复单元 2,3 位上的苯基的影响。聚合物的表征采用核磁共振光谱、紫外可见吸收光谱和荧光光谱,分子量的估算采用凝胶渗透色谱法。聚合物 P1-P4 可吸收高达 900 纳米的光线,能量隙在 1.37 至 1.40 eV 之间。在白光照明下,ITO/PEDOT:PSS/P2:PC70BM(1/4, w/w)/Al光伏电池的开路电压为0.60 V,功率转换效率为0.67%,短路电流为3.6 mA cm-2。