ZnO-SiO2的制备及其光催化降解罗丹明B

采用溶胶-凝胶法制备负载型ZnO-SiO2光催化材料,研究升温速率及负载量对ZnO结构、形貌及光催化活性的影响.通过X射线衍射、N2物理吸附-脱附、扫描电子显微镜、光致发光光谱和紫外-可见漫反射光谱等手段对催化剂进行表征,并以罗丹明B为模拟污染物,紫外光为光源,评价催化剂活性.结果表明,升温速率对ZnO-SiO2光催化剂结晶度和光催化活性影响显著.当ZnO与SiO2的质量比为1∶1时,ZnO-SiO2具有均匀、平滑的球形形貌,并且ZnO光催化活性明显改善.

Fabrication of ZnO-SiO2 and Its Photocatalytic Degradation of Rhodamine B

ZnO-SiO2 composite photocatalysts were prepared by a facile sol-gel process.The effect of heating rate and deposition process on structure, morphology and photocatalytic activity of ZnO-SiO2 was studied.Products were characterized by X-ray diffraction, N2 adsorption-desorption techniques, scanning electron microscopy, UV-Vis diffuse reflectance spectra and photoluminescence.Rhodamine B was used as model dye to evaluate the photocatalytic activity of ZnO-SiO2 composite photocatalysts.The results show that the heating rate has greatly impact on photocatalytic activity of ZnO-SiO2.Scanning electron microscopy images show uniform deposition of zinc oxide nanoparticles on the surface of silica spheres.When the weight ratio of ZnO to SiO2 is 1∶1, the highest photodegradation rate is found.