可见光催化剂Ag_3VO_4的制备、表征及其光催化性能的研究

通过化学沉淀的方法来制备光催化剂Ag3VO4,用紫外-可见光谱、X射线衍射和荧光光谱对其进行表征.通过光催化还原Cr6＋和光催化氧化甲基橙的效率来评价该催化剂的活性.实验研究了不同的制备条件对Ag3VO4催化活性的影响.实验结果表明,在可见光下,在过量银条件下制备的Ag3VO4有较好的光催化氧化活性和光催化还原活性,且其紫外-可见吸收光谱有较大程度的红移,提高了对光的利用率.实验同时还研究了在过量银条件下制备出的Ag3VO4的稳定性和循环次数.同时对影响Ag3VO4的光催化活性的机理还进行了探讨.

The preparation characterization and activity evaluation of visible-light-driven photocatalyst Ag_3VO_4

The photocatalyst Ag3VO4 was prepared by the chemical precipitation method.The photocatalyst was characterized by X-ray powder diffraction（XRD）,UV-Vis diffuse reflectance spectroscopy（UV-Vis） and Photoluminescence（PL） emission spectra.The photocatalytic activity of the photocatalyst was evaluated by photocatalytic reduction of Cr2O2-7 and photocatalytic oxidation of Methyl Orange（MO）.The effect of different preparation conditions on the photocatalytic activity of Ag3VO4 was investigated.The results showed that the Ag3VO4 photocatalyst prepared in the presence of excess silver exhibited the excellent photocatalytic reduction activity of Cr2O2-7 and photocatalytic oxidation activity of Methyl Orange（MO） under visible light irradiation.And the photoabsorption wavelength range of the photocatalyst red shifts and the utilization of the total spectrum improves.As for the Ag3VO4 photocatalyst（Ag/V=6：1）,the stability and cycling runs are studied.The possible mechanisms of influence on the photocatalytic activity of the Ag3VO4 photocatalyst were also discussed.