Electrochromic properties of sputtered Ni oxide thin films in neutral KCl electrolytes

Thin films of Ni oxide, which is a promising anodic electrochromic material, were deposited by reactive RF sputtering at 40, 60, and 100 watts, and their electrochemical and electrochromic properties were examined using neutral KCl electrolytes. Higher charge capacity and higher optical modulation were obtained for a Ni oxide film deposited at low sputtering power and low deposition rate. Electrochromic coloration efficiencies of approximately 30 cm^2/C were obtained for all the Ni oxide films in KCl regardless of RF power value