Zn^(2+)掺杂高岭石基纳米TiO_2光催化材料的表面特性研究

Research on Surface Characteristics of Zn^(2+) Doping Nano-TiO_2/Kolinite Photocatalytic Composite

基于高岭石表面是以Si-O键为主的亲水表面且具有巨大比表面积,易于复合光催化优异的TiO2膜。以高岭石为基材,溶胶-凝胶法制备了具有光催化活性的Zn2+掺杂TiO2/高岭石复合光材料。采用XRD、FTIR、Raman、XPS等技术对材料的晶体结构、分子结构、表面元素组成及化学态、纳米TiO2晶体膜的覆盖面积进行表征分析。结果表明:Ti-O与高岭石结构的Si-O发生化学键合,在高岭石表面形成Si-O-Ti键合的纳米TiO2晶体膜,占高岭石表面积的91.35%。掺杂的Zn2+只是在TiO2晶体表面复合氧化成红锌矿,而不能进入TiO2晶格。物理化学复合增加了基材高岭石表面晶体缺陷,有利于TiO2晶体表面光生载流子的增生和传输。

The excellent photocatalysis capability of crystal film of TiO2 was synthesized base on the Si-O bonds hydrophile surface and tremendous smooth specific area of kaolinite. The Zn^2＋ doped TiO2/kolinite photocatalyst was prepared using kaolinite as based materials by sol-gel method. The crystal andmolecular structures, composition and chemical state of surface elements and coveraged area of nano-TiO2 crystal film were characterized by XRD, FTIR, Raman and XPS techniques. The results showed that a nano-TiO2 crystal film was synthesized as the produced due to Ti-O bond to be chemical combination with the Si-O bond of the kaolinite structure. The superficial area of nano-TiO2 crystal film is 91.35% for thesurface area of kaolinite. Zn2~ dopped has been composited and oxidized into nano-TiO2 crystal film rather than interior of space lattice of TiO2. The physical enhanced carrier of crystal surface faultiness and in favor of multiplication and transmission of nano-TiO2 for substrates kaolinite. zincites on surtace of a chemistry recombination photoproduction charge