Jiang Xueding, Xu Weicheng, Yu Lian
School of Environmental and Chemical Engineering, Foshan University, Foshan 528000, China.
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
Nanomaterials (Basel). 2019 Mar 2;9(3):338. doi: 10.3390/nano9030338.
Ag nanoparticles loaded onto TiO₂ nanosheets with exposed {001} facets were synthesized by solvothermal hydrolysis and photoreduction deposition methods. The results suggested that Ag NPs were uniformly dispersed on the surface of anatase TiO₂ NSs with a metallic state. The Raman scattering and visible light absorption performances of Ag/TiO₂ NSs were enhanced by Ag NPs due to their surface plasmon resonance effect. Photocatalytic oxidation experiments for HCHO were carried out under visible light, and the enhanced photocatalytic activity of Ag/TiO₂ NSs can be attributed to the synergistic effects of the following factors: (1) the {001} facets, which possessed higher surface energy, showed higher photocatalytic activity; (2) the Ag NPs, the increased oxygen vacancies, and O₂ adsorption on {001} facets can trap photoelectrons, thus inhibiting the recombination of photoelectrons and holes; (3) the Ag NPs can extend the light response range of TiO₂ into visible light. The in situ FTIR results showed that higher mineralization efficiency of HCHO was achieved on Ag/TiO₂ NSs than on Ag/TiO₂ NPs. Additionally, the mechanism for HCHO photocatalytic oxidation was also discussed.
通过溶剂热水解和光还原沉积法合成了负载在具有暴露{001}面的TiO₂纳米片上的Ag纳米颗粒。结果表明，Ag NPs以金属态均匀分散在锐钛矿型TiO₂ NSs表面。由于Ag NPs的表面等离子体共振效应，Ag/TiO₂ NSs的拉曼散射和可见光吸收性能得到增强。在可见光下进行了HCHO的光催化氧化实验，Ag/TiO₂ NSs增强的光催化活性可归因于以下因素的协同作用：(1)具有较高表面能的{001}面表现出较高的光催化活性；(2)Ag NPs、增加的氧空位以及{001}面上的O₂吸附可以捕获光电子，从而抑制光电子和空穴的复合；(3)Ag NPs可以将TiO₂的光响应范围扩展到可见光。原位FTIR结果表明，Ag/TiO₂ NSs上HCHO的矿化效率高于Ag/TiO₂ NPs。此外，还讨论了HCHO光催化氧化的机理。
