Realizing Flexible Multicolored Electrochromism on Carbon Nanotubes through Thin-Film Interference

Carbon nanotubes (CNTs) have found widespread applications in the fields of mechanics, microelectronics, and optoelectronics. However, the attractive applications of CNTs in functional coatings and smart textiles are severely limited by their inherent black appearance. Herein, the rich coloration of CNTs is achieved by depositing tungsten oxide (WO3) of varying thicknesses onto the surface of CNT films, based on the thin-film interference effects. Additionally, by constructing inverted-type electrochromic devices, we achieved dynamic color modulation of the CNTs. These flexible electrochromic devices exhibit dynamic color modulation, robust mechanical flexibility, and electrochemical stability, demonstrating significant potential for applications in embedded wearable electronics, smart textiles, and functional coatings.