Benzodithiophene-Based Poly(aryleneethynylene)s: Synthesis, Optical Properties, and Applications in Organic Solar Cells

The synthesis and characterization of building block of ethynylene-substituted benzo[1,2-b:4,5-b]dithiophene (BDT), and its application in the construction of poly(aryleneethynylene)s (PAEs) are described in this article. Alkoxy-substituted BDT and thiazolothiazole are selected as the other copolymerized units, and polymers of PEBBDT and PEBTTZ were synthesized by Pd-catalyzed Sonogashira coupling reaction. These polymers showed intense interchain - interaction and deep HOMO levels ( -5.50 eV). Bulk heterojunction solar cell fabricated using PEBBDT or PEBTTZ as electron donor and PC61BM as acceptor display power conversion efficiency of 0.85 and 2.40%, respectively, under the illumination of AM1.5G, 100 mW cm(-2). This study shows good prospect for the application of PAEs-type polymers in organic solar cell. (c) 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 208-215