Effect of Cu2+ doping on photocatalytic performance of liquid flame sprayed TiO2 coatings

Cu²⁺ was added to liquid feedstock to deposit ion doping TiO₂ photocatalytic coatings through liquid flame spraying. The coating microstructure was characterized by x-ray diffraction (XRD), transmission electron microscopy, and x-ray photoelectron spectroscopy (XPS). The photocatalytic performance of coatings was examined by photodegradation of acetaldehyde. The XRD analysis shows that the crystalline structure of coatings is not significantly influenced by Cu²⁺ doping. The photocatalytic activity of the TiO₂ coatings is enhanced by Cu²⁺ doping. It is found that a high concentration of Cu²⁺ doping decreases the activity. The XPS analysis shows that the adsorbed oxygen concentration is increased with the increase of Cu²⁺ dopant concentration and decreases with a further increase of dopant concentration. The enhancement of photocatalytic activity can be attributed to the adsorption ability of oxygen and other reactants on the surface of doping TiO₂ coatings. This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials Park, OH, 2006.