Anticorrosion Behaviours of the TiO{sub}2/WO{sub}3 Composite Photoelectrodes for 304 Stainless Steel

摘要

TiO{sub}2 is one kind of semiconductor-based photocatalyst. TiO{sub}2 shows relatively high reactivity and chemical stability under ultraviolet (UV) light. However TiO{sub}2 is a poor absorber of photons in visible light. In order to improve the absorption efficiency, the coatings of TiO{sub}2/WO{sub}3, WO{sub}3 and TiO{sub}2 on ITO were prepared by liquid phase deposition (LPD) and dip coating method, their microstructure, surface properties, photoelectrochemical properties are investigated in this paper. XRD results showed that the phases on the composite coatings are mainly anatase, rutile and WO{sub}3 respectively, the SEM results showed that the coatings of TiO{sub}2 and TiO{sub}2/WO{sub}3 are distributed evenly on the materials surface. The electrochemical experiment results showed that open circuit potential of TiO{sub}2 and TiO{sub}2/WO{sub}3 with presence of the UV light illumination were about -343 mV and -650 mV respectively, comparatively the rest potential of 304 stainless steel is about 48 mV, which means that the TiO{sub}2 or TiO{sub}2/WO{sub}3 coatings can protect 304 stainless steel from corrosion, and TiO{sub}2/WO{sub}3 coatings retained for a while anticorrosion even absence of UV light.