Electrochromic Behavior of Manganese Oxides/Silver Thin Films from Electrochemical Deposition

MnOx thin films with silver additives were electrochemically deposited on an Indium Tin Oxide (ITO) substrate with silver acetate and potassium permanganate aqueous solution. The addition of Ag enhanced electrochromic behavior during cyclic voltammetry (CV). The morphology of the thin films was examined by using scanning electronic microscopy (SEM) and transmission electron microscopy (TEM). The chemical states of Mn and Ag ions on the surfaces of the thin films were examined using X-ray photoelectron spectroscopy (XPS). Spherical Ag2O and Ag nanoparticles were homogeneously dispersed on the thin films. The electrochemistry of the thin films was examined by cyclic voltammetry in a conventional three-electrode system and an electrochemically tested system. The electrochromic behavior of the films was demonstrated through the cyclic voltammetry (CV) process in the KNO3 electrolyte. The electrochromic behavior of the thin films depended on the redox reactions associated with the reaction between Ag and Ag2O coupled with Mn4+ ions and Mn3+ ions in the KNO3 electrolyte.