H_3PW_(12)O_(40)/TiO_2可见光下光催化降解孔雀石绿的研究

以钛酸四丁酯为原料,采用溶胶-凝胶法制备TiO2光催化剂,然后浸渍法制备出H3PW12O40/TiO2复合型光催化剂,并运用XRD、SEM、FT-IR和DRS对催化剂进行表征和分析.研究了可见光光照下H3PW12O40/TiO2对孔雀石绿降解的光催化活性,考察了浸渍量、催化剂用量、底物浓度、pH值对光催化降解率的影响.实验表明,在pH=5条件下,H3PW12O40/TiO2催化剂用量为0.3g.L-1,浓度为10mg·mL-1的孔雀石绿溶液在2L·min-1曝气、300W可见光下光照4h后光催化降解率为78%,比TiO2光催化活性提高了24%.

Photocatalytic degradation of malachite green by H3PW12O40/TiO2 under visible-light irradiation

A composite H3PW12O40/TiO2 photocatalyst was prepared by impregnating H3PW12O40 onto nanosized TiO2, which was prepared by a sol-gel method with tetrabutyl titanate. The composite photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR) and UV-Vis diffuse reflectance spectroscopy (DRS). The photocatalytic activity of the catalyst toward decomposing malachite green (MG) was studied under visible-light irradiation. The influences of several operating parameters, such as impregnation volume, the dosage of catalyst, initial dye concentration, and pH, on the photocatalytic degradation of MG were investigated. The degradation rate of MG with H3PW12O40/TiO2 was 78% after being treated for 4 h under 300 W visible-light irradiation at pH 5, with 2 L·min-1 aeration using 0.3 g·L-1 H3PW12O40/TiO2 as the photocatalyst, which was higher than that when using TiO2 photocatalyst alone.