Syntheses and Electrochemical Characterization of Low Oxidation Potential Nitrogen Analogs of Pedot as Electrochromic Materials

Abstract

In this study, the electropolymerization of ethyl and methyl substituted asymmetrical nitrogen analogs of 3,4-ethylenedioxythiophene (OEt and OMe) were synthesized, characterized and their electrochemical properties were investigated. Both polymers (POEt and POMe) were synthesized electrochemically and characterized using spectroelectrochemical technique to determine optical changes of the resulting polymer films. Electrochemical studies demonstrated that these polymers exhibited a significantly low oxidation potential compared to their analogs reported in the literature. These polymers also provided a low optical bandgap with good optical contrasts. Furthermore, multi-electrochromic properties upon different applied potentials revealed that these polymers have potential applications in electrochromic devices. As a further characterization, their dual type electrochromic devices were constructed with poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) which is transmissive in its both redox states. Devices were characterized via electrochemical and spectroelectrochemical techniques.