A novel quinoxaline-based donor-acceptor type electrochromic polymer

We synthesize a quinoxaline-based novel conjugated donor–acceptor random copolymer containing benzodithiophene and 2,5-difluorophenylenedithiophene units as electron donors (coded r-PQ) and investigate the electrochromic properties of the material. Despite its high molecular weight, r-PQ is highly soluble in organic solvents owing to the side chain of alkoxy at the meta-position of the phenyl ring. The r-PQ film exhibits excellent redox-promoted blue to transmissive-state color switching with high coloration efficiency (>250cm2/C) and a fast response time (<0.5s). These results suggest that our quinoxaline-based random copolymer could be a promising candidate as an organic electrochromic material.