Well-matched materials: Color palettes-like multicolor electrochromic displays

In order to fabricate a multicolor display, two viologen materials with distinct electrochromic properties and well-matched colored states were developed. Polyvinyl alcohol (PVA)-based electrochromic (EC) gels containing either 1,1 '-diheptyl-4,4 '-bipyridinium dibromide (DHV) or 1,1 '-bis(p-cyanophenyl)-4,4 '-bipyridinium (p-CV) demonstrate a spectrum of colors within a single device facilitated by introducing a double-sided ITO (dsITO). Each color can be controlled independently or simultaneously. By adjusting the voltage applied to the device, a variety of colors and patterns can be displayed due to similar colored voltages and different electrochromic characteristics.