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以碱-水热法在金属Ti片上原位生长了TiO2纳米结构(纳米花和纳米线)薄膜,并采用低温静电自组装方法将超细贵金属(金、铂、钯)纳米颗粒均匀沉积于多孔TiO2薄膜上.负载于Ti片上的贵金属/TiO2纳米结构薄膜具有一体化结构、多孔架构和高光催化活性.超高分辨率场发射扫描电子显微镜(FESEM)直接观察表明贵金属纳米颗粒在TiO2表面分布均匀,且颗粒之间相互分离,金、铂、钯纳米颗粒的平均粒径分别约为4.0、2.0和10.0nm.俄歇电子能谱(AES)纵深成分分析表明贵金属不仅沉积于薄膜表面,且大量分布于TiO2纳米结构薄膜内部,其深度超过580 nm.X射线光电子能谱(XPS)分析表明,经300°C下在空气中热处理后,纳米金仍保持金属态,纳米铂部分被氧化成PtOabs,而钯粒子则完全被氧化成氧化钯(PdO).以低温静电自组装法沉积贵金属,贵金属负载量可通过调节组装时间与溶胶pH值来控制.光催化降解甲基橙的结果表明,沉积的纳米金和铂能显著增加TiO2纳米结构薄膜的光催化活性,说明金和铂粒子可促进光生载流子的分离;但负载的PdO对TiO2薄膜的光催化性能增强几乎无作用.
TiO2 nanostructures (nanowires and nanowires) films were grown in situ on the Ti substrate by alkali-hydrothermal method. The ultrafine precious metal (Au, Pt, Pd) nanoparticles were uniformly deposited on the porous TiO2 thin film.The noble metal / TiO2 nanostructured film supported on Ti has an integrated structure, porous structure and high photocatalytic activity.The direct observation of ultra-high resolution field emission scanning electron microscopy (FESEM) shows that the noble metal nanoparticles are uniformly distributed on the surface of TiO2 , And the particles are separated from each other, and the average particle sizes of the gold, platinum and palladium nanoparticles are about 4.0, 2.0 and 10.0 nm, respectively. The AES analysis shows that the precious metal is not only deposited on the surface of the film, Which were distributed inside the TiO2 nanostructured films with a depth of more than 580 nm.X-ray photoelectron spectroscopy (XPS) analysis showed that after heat treatment in air at 300 ° C, the gold nanoparticles remained in the metal state and the platinum nanoparticles were partially oxidized into PtOabs , While the palladium particles are completely oxidized to PdO. The noble metal is deposited by cryogenic electrostatic self-assembly, and the noble metal loading can be controlled by adjusting the assembly time and the pH of the sol. Degradation of methyl orange results show that the deposition of gold and platinum can significantly increase the photocatalytic activity of TiO2 nanostructured film, indicating that gold and platinum particles can promote the separation of photo-generated carriers; but the photocatalytic activity of TiO2 film Performance enhancements have almost no effect.