Facile fabrication of crack-free large-area 2D WO3 inverse opal films by a 'dynamic hard-template' strategy on ITO substrates

A 'dynamic hard-template' infiltration strategy for crack-free large-area synthesis of 2D WO3 inverse opal (IO) films on ITO substrates using a wide range of sizes of sacrificial PS spheres is reported. Thus prepared WO3 IO films were successfully used as an active electrode in the fabrication of an electrochromic device.