Non-conjugated electrochromic supercapacitors with atom-economic arylamine-based AB2-polyamides

Abstract

A highly atom-economic AB₂-type hyperbranched polyamide (HPA) derived from arylamine monomers was judiciously designed and prepared. This electroactive HPA was further end-capped with two different end-cappers to prepare HPA-B and HPA-TPA with intrinsic microporous structures, which exhibited improved counter-ion diffusivity in electrochemical processes. With the aid of the intrinsic microporous structure, HPA-TPA revealed outstanding characteristics such as three-stage color changes, the highest coloration efficiency (CE), and the shortest switching response times among the prepared redox-active polyamides. Electrochromic devices employing ECD-HPA-TPA in this study demonstrated remarkable performance, evidenced by their rapid coloration rate of 27.4% s⁻¹ and impressive switching stability. While evaluating and comparing the capacitive behavior of the HPA-TPA film, it showed 73.2 F g⁻¹ at 1.0 A g⁻¹ with nearly 60% transmittance contrast with only 220 nm thickness, and stability with 90.2% retention in a 300-cycle charge–discharge process. Furthermore, we compared its stability with polyamides derived from triphenylamine-based diamines to elucidate the effect on the reversibility during the charge–discharge process.