商用TiO2负载贵金属光催化剂的制备及其降解含染料废水的性能研究

Preparation of noble metal supported commercial TiO2 photocatalyst and its degradation performance for dye-containing wastewater

以商用TiO2(Macklin P25)为载体,采用聚乙烯吡咯烷酮(PVP)或聚乙烯醇(PVA)保护的还原法制备M/TiO2(M为Ag、Au、Pd或Pt,M理论质量分数均为0.5%)光催化剂,利用X射线粉末衍射、紫外-可见漫反射光谱、荧光光谱等分析手段对TiO2及M/TiO2的物化性质进行了表征,并对其在可见光照射下降解甲基橙(MO)的光催化活性进行评价。结果表明,Pt/TiO2具有优良的可见光驱动降解MO的光催化活性,这与其具有纯锐钛矿晶相、强可见光吸收性能、低带隙能(2.89eV)以及光生电子和空穴的低复合率有关。

With the commercial TiO2(Macklin P25)as the support,M/TiO2(M=Ag,Au,Pd or Pt,the theoretical M weight percentage was 0.5 wt%,respectively)photocatalysts were prepared using the polyvinyl pyrrolidone(PVP)or polyvinyl alcohol(PVA)-protected reduction methods.Physicochemical properties of the TiO2 and M/TiO2 samples were characterized by X-ray powder diffraction(XRD),ultraviolet visible diffuse reflection spectroscopy(UV-Vis DRS),photoluminescence(PL)spectrum analysis technology,and their photocatalytic activities were evaluated for the removal of methyl orange(MO)under visible-light illumination.It was found that the high visible-light-driven catalytic performance of the Pt/TiO2 sample was associated with its pure anatase crystal phase,strong visible light absorption performance,low bandgap energy(2.89 eV)as well as low recombination rate of photogenerated electrons and holes.