Cyclic voltammetric, chronocoulometric, and spectroelectrochemical studies of electropolymerized films based on (3,4-ethylenedioxythiophene)-substituted 3,6-dithiophen-2-yl-2,5-dihydropyrrole[3,4-c]pyrrole-1,4-dione

Abstract

A new compound with the core luminescent dye unit diketopyrrolopyrrole (DPP), namely 3,6-dithiophen-2-yl-2,5- dihydropyrrole[3,4-c]pyrrole-1,4-dione (DTDPP), attached to 3,4-ethylenedioxythiophene (EDOT) was synthesized. From this monomer, polymer films were prepared on glassy carbon and indium tin oxide surfaces using cyclic voltammetry. The films were characterized using cyclic voltammetry, chronocoulometry, and atomic force microscopy. The electropolymerization of the monomer exhibits reversible electrochemistry that transitions to quasireversible electrochemistry. During electropolymerization, the overpotential for the reduction process exceeds the overpotential for the oxidation process and cyclic voltammetric characterization of the films demonstrates that oxidation is more favored than reduction. Spectroelectrochemical measurements confirm that the polymer films demonstrate electrochromic behavior that correlates to the electrochemical observations during characterization of the films.