Electrochromic Behavior of Amorphous Copperphthalocyanine Thin Films

Abstract

Amorphous and polycrystalline copperphthalocyanine thin films were prepared by vacuum evaporation, and their electrochromic behavior and voltamogramms were examined in a liquid electrolyte. Amorphous films prepared at the substrate temperature of -130°C underwent three color transitions (from blue to violet, then to green and to blue again) corresponding to the three peaks on the voltamogramms in the lithium perchlorate solution. In contrast, the polycrystalline thin films prepared at the substrate temperature of 180°C did not exhibit color change.