Solution polarity modulated electrochromic devices with tunable colored states

Abstract

Electrochromic devices (ECDs) hold great promise for applications in displays and smart military camouflage. However, achieving different electrochromic colored states with compatible integration into a monolithic device remains a significant challenge. In this study, we realized effective color modulation of ECDs by tuning the solvent composition, leveraging the the effects of solvent polarity. The resulting ECDs exhibited tunable absorption peaks and color switching behaviors across various solvent systems. The ECDs achieved a high optical contrast of 74%, while maintaining a coloration efficiency of 41.6 cm²/C.