Eu3＋、Si4＋共掺杂TiO2光催化剂的协同效应

采用溶胶-凝胶-浸渍法制备了Eu/Ti/Si纳米光催化剂, 并通过XRD、FT-IR、EPR等进行了表征.结果表明,掺入Eu3＋和Si4＋, 阻止了TiO2从锐钛矿晶型向金红石晶型的转变, 使TiO2的粒径减小, 且Eu3＋能够促进Si4＋进入TiO2的晶格中.以甲基橙为光催化反应模型化合物, 考察了光催化剂的活性.测定了甲基橙在不同光催化剂上的吸附常数,探讨了催化剂对甲基橙的吸附机理. Eu3＋和Si4＋的最佳掺入量分别为wEu=0.03％、wSiO2=39.06％,且Eu3＋和Si4＋同时掺入TiO2光催化剂产生协同效应.讨论了光催化活性与催化剂性质的关系.

Synergistic Effect of Eu3+ and Si4+ Co-doping on Photocatalytic Activity of Titanium Dioxide

Eu/Ti/Si composite photocatalysts were prepared by sol-gel-soaking process and characterized by XRD, FT-IR and EPR. It has been shown that the particle diameter of Eu/Ti/Si photocatalysts decreased, the crystal transformation of titania from anatase to rutile was prevented, and the incorporation of Si4＋ into the matrix of the TiO2 was promoted owing to the co-doping of Si4＋ and Eu3＋. As a model reaction, the photocatalytic degradation of methyl orange was investigated. The adsorption constants of methyl orange over catalysts were evaluated and the adsorption mechanism was also discussed. Optimal doping amounts for Si4＋ and Eu3＋ are wSiO2=39.06％ and wEu=0.03％ respectively, and the co-doping of them shows a synergistic effect for photocatalytic activity of titanium dioxide. Relation between photocatalytic activity and property of the photocatalyst was discussed.