Sm_2O_3掺杂TiO_2光催化剂的制备和性能

Preparation and Properties of Sm_2O_3-Doped TiO_2 Photocatalyst

采用溶胶 凝胶法制备了Sm2 O3 掺杂TiO2 光催化剂 ,通过X射线衍射、程序升温脱附和漫反射紫外 可见光谱等手段对催化剂进行了表征 ,并以苯酚为光催化降解反应模型化合物考察了光催化剂的活性 ,测定了苯酚在TiO2 和Sm2 O3 掺杂TiO2光催化剂上的吸附常数 .结果表明 ,Sm2 O3 掺杂TiO2 光催化剂具有较强的紫外光吸收性能 .Sm2 O3 掺杂使TiO2 粒径减小 ,比表面积增大 ,同时导致氧脱附温度提高及脱氧量增大 .Sm2 O3 掺杂有利于反应底物在催化剂表面的吸附 ,Sm2 O3 的最佳掺入量为Sm/Ti摩尔比 =0 8% .

The TiO 2 photocatalyst doped with Sm 2O 3 was prepared by the sol-gel method and characterized by means of X-ray diffraction, temperature-programmed desorption, and diffuse reflectance ultraviolet-visible spectroscopy. The Sm 2O 3-TiO 2 catalyst showed stronger absorption in the ultraviolet region than the pure TiO 2. After doping with Sm 2O 3, the particle diameter of the catalyst decreased, the specific surface area increased, and the desorption temperature and desorption amount of oxygen on the catalyst increased. Using phenol as the model compound of the photocatalytic degradation reaction, the activity of the prepared photocatalysts was investigated in suspension irradiated by a high-pressure mercury lamp. As a result, the addition of Sm 2O 3 to TiO 2 notably enhanced its photocatalytic activity. The adsorption constants of phenol on the Sm 2O 3-TiO 2 and the unmodified TiO 2 catalysts were evaluated, and the results showed that the adsorption of phenol on the Sm 2O 3-TiO 2 catalyst was improved. The optimum doping amount of Sm 2O 3 was obtained at a Sm/Ti molar ratio of 0.8%.