室温水汽对Au/TiO2上光催化分解臭氧的影响

 采用沉积-沉淀法制备了Au/TiO2光催化剂,并用紫外-可见漫反射光谱和X射线光电子能谱对其进行了表征,详细考察了室温水汽的引入对Au/TiO2光催化分解臭氧活性的影响. 结果表明,同干燥状态时相比,室温引入水汽后催化剂活性较低,并且较快地达到了稳定值. 催化剂的O 1s和Au 4f的XPS分析结果表明,水汽的存在导致TiO2的表面结构发生变化,进而使金-载体之间的相互作用力减弱. 这是导致催化剂活性下降的主要原因.

Effect of Water Vapor at Room Temperature on Photocatalytic Decomposition of Gaseous Ozone over Au/TiO2

The Au/TiO_2 photocatalyst was prepared by the deposition-precipitation method and was characterized by UV-Vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The influence of water vapor at room temperature on the photocatalytic activity of Au/TiO_2 for ozone decomposition was studied. The results showed that the catalytic activity of Au/TiO_2 decreased significantly when water vapor was introduced into the dried feed gas. In addition, the ozone removal rate over Au/TiO_2 reached a steady value rapidly. The results of O 1s and Au 4f XPS showed that the surface structure of TiO_2 was changed, and the interaction between the gold and the support was weakened in the presence of water vapor, which was responsible for the decrease in the photocatalytic activity of the catalyst.