Journal Article electrochromic tungsten oxide Fabry-Pérot cavities Fabry‐Perot cavity Kallima inachus N-doped Research Support, Non-U.S. Gov't Review all solid state catalyst color variations different voltages electrocatalysts electrochemical deposition electrochromic battery electrochromic device electrochromic devices with dual-sided differential colorations electrochromic materials and devices electrochromism excellent cycling lifetimes fast response times high capacity ionic liquid MPII3 light-matter interactions low‐frequency sound manganese oxide molecular ferroelectrics multicolor multicolor properties