A tunable color palette of electrochromic materials achieved through an ingenious stacking of ordinary conducting polymers

Abstract

Obtaining a wide color gamut and controllable color switching of electrochromic polymers (ECPs) is crucial for advanced applications. In this study, we present a multicolor palette of ECPs based on thin and transparent films of three ordinary conducting polymers: polythiophene (red), polyaniline (green), and poly(3,4-ethylenedioxythiophene) (blue). We utilized the liquid/liquid interfacial route to produce the polymer films and achieved different color tones by stacking them in varying combinations and/or numbers of layers. Thirteen distinct colors, covering the fully visible spectrum, were prepared, and their electrochromic properties were demonstrated. Fine-tuning of the colors is possible by carefully selecting the stacked samples and applying voltage. Finally, we create a rainbow-like, multicolored electrode to showcase the potential of this technique in producing multifunctional and spatially controlled electrodes for advanced electrochromic technologies.