光沉积法合成纳米金属Pd负载的MCM-TiO2及其光催化性质研究

用光沉积方法由PdCl₄^2-和Ti修饰的MCM-41合成了纳米钯团簇Pd/MCM-TiO₂,用XPS,N₂吸脱附等温线,UV-Vis和Raman光谱对其结构进行了表征.将该团簇用于苯酚的光降解和Cr(Ⅵ)还原为Cr(Ⅲ)的反应中,表现出较高的光催化活性.

Synthesis, Structure Characterization and Photoactivities of Nanosized Pd Clusters on Titania-modified MCM-41 by Photodeposition Method

Nanosized Pd clusters deposited on titania modified MCM-41 was synthesized by photodeposition method through PdCl₄^2- and titania modified MCM-41. The structure and optical properties of the as synthesized samples were investigated by XPS, N₂ adsorption/desorption isotherms, diffuse reflectance UV-Vis absorbance spectroscopy and Raman spectroscopy. Metallic palladium was efficiently photoreduced on the surface of titania in the mesopore from PdCl₄^2- according to the results of XPS. The adsorption revealed that titania and noble Pd clusters were uniformly distributed on the silica wall surfaces of MCM-41 support. The configuration of partial titania in Pd deposited titania modified MCM-41 changed from tetrahedral to octahedral from the results of adsorption in UV-Vis spectra and Raman spectra because of the interactions between the loaded Pd clusters and titania. The Pd deposited titania modified MCM-41 exhibited a high photocatalytic activity for the photodegradation of phenol and the photoreduction of Cr(Ⅵ) to Cr(Ⅲ).