Improved reversibility of color changes in electrochromic Ni-Al layered double hydroxide films in presence of electroactive anions

► Electroactive anions in solution mediate complete reduction of oxidized Ni-Al-LDHs. ► Anions adsorbed in the LDH interlayer are effective as redox mediators. ► Their presence greatly improved reversibility of the color changes in LDHs films. ► The reversible color changes could be sustained over multiple potential scans. ► Makes Ni-Al-LDHs potentially useful for use in electrochromic devices.