Electrochemical polymerization, characterization and spectroelectrochemical studies of a N-substituted-2,5-dithienil-pyrrole bearing an aniline moiety for cross-linking (TPTBA)

Abstract

N-substituted-2,5-dithienil-pyrroles have demonstrated to be an interesting alternative for the preparation of π-conjugated polymers with good electrochromic properties. Herein the 4-(4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzyl)aniline (TPTBA) was chemically synthetized and its electrochemical behavior and polymerization was studied. The obtained film was characterized by electrochemical and spectroelectrochemical methods. Poly-TPTBA presents a quasi-symmetrical reversible redox system characteristic to well-ordered systems. This explained by the presence of the aniline moiety which can favor a cross-linking of the polymer backbone. Spectroelectrochemical studies reveal a moderate rapid electrochromic transition between both redox states, requiring 2 seconds to alternate between each color: 430 nm (discharged state) and 800 nm (charged state).