Electrochromic properties of Au–WO3 nanocomposite thin-film electrode

We observed proton transfer phenomenon of WO3 in Au–WO3 nanocomposite thin-film electrode prepared by sputtering deposition method. The Au–WO3 nanocomposite electrode formed using both the Au and WO3 targets consisted of a nano-sized Au crystalline phases and a tungsten oxidative phase, indicating the formation of crystalline Au nanophases, as confirmed by X-ray diffraction analysis and X-ray photoelectron spectroscopy. In particular, due to Au metallic nanophases, the modified electrochromic and electrochemical properties of WO3 were observed. The Au–WO3 electrode showed a reverse optical modulation with respect to applied potential compared to that of WO3 electrode.