Solid‐state electrochromic cell with anodic iridium oxide film electrodes

A new solid‐state electrochromic cell has been fabricated using an anodic iridium oxide film (AIROF) display electrode. The cell has the symmetric sandwich structure AIROF‖Nafion‖AIROF, with the Nafion solid electrolyte opacified by an in situ precipitation technique. A symmetric square‐wave voltage of 1.5 V amplitude produces clearly perceivable color changes from pale to dark blue‐gray in ≈1 sec when viewed in diffuse reflection. Good open‐circuit optical memory is exhibited: (typical loss in attenuation of 8%/day).