Photoelectrochromic properties of NiO film deposited on an N-doped TiO2 photocatalytical layer

N-doped TiO2 film was synthesized on indium-tin oxide (ITO) conducting glass substrate by the hydrolysis method and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Then high porous NiO was deposited onto the TiO2-N-x(x) layer by chemical bath deposition (CBD) to prepare a double-layer TiO2-N-x(x)/NiO electrode. The photoelectrochromic properties of the TiO2-N-x(x)/NiO electrode were discussed through the results of UV-vis transmittance spectra, cyclic voltammogram and photocurrent transient measurements. It was found that the TiO2-N-x(x)/NiO electrode was sensitive to light and exhibited a noticeable photoelectrochromism. The NiO film changed its color from colorless to brown, and the transmittance varied from 86.8% to 14.5% at 500 nm after 1 h irradiation. (C) 2009 Elsevier Ltd. All rights reserved.