水热法制备ZnTiO3/TiO2复合光催化剂及其光催化性能研究

The synthesis of ZnTiO3/TiO2 composite photocatalysts and their photocatalytic performances

摘要:

本文以层状钛酸盐K2Ti4O9为前驱体，将其通过质子交换和插层反应剥离成[Ti4O9]2ˉ纳米片，然后用3 mol/L HCl溶液和3 mol/L NaOH溶液将其调节成设定pH，再向上述溶液中加入一定质量的六次甲基四胺和锌盐，在水热条件下制备出高催化活性的ZnTiO3/TiO2复合光催化剂. 通过X-射线粉末衍射仪（XRD）和扫描电镜（SEM）表征了其结构和形貌，并在光照条件下，对不同条件下所制备的ZnTiO3/TiO2复合光催化剂进行了光催化降解亚甲基蓝性能研究. 研究结果表明，在pH = 7.0条件下制备的ZnTiO3/TiO2复合光催化剂展示了较高的光催化性能.

Abstract:

The ZnTiO3/TiO2 composite photocatalysts with high photocatalytic activity were synthesized by hydrothermal treatment of the [Ti4O9]2ˉ nanosheets after it was adjusted to a desired pH value with a 3 mol/L HCl solution and a 3 mol/L NaOH solution in the present of hexamethylenetetramine and Zn(NO3)2. The [Ti4O9]2ˉ nanosheets were prepared by using the layered tetratitanate K2Ti4O9 as the processor. First, the K2Ti4O9 sample was converted into a protonic tetratitanate H2Ti4O9 by exchanging K+ of K2Ti4O9. And then the H2Ti4O9 was mixed with the triethanolamine (TEAOH) to obtain the TEA+-intercalated tetratitanate compound. Finally, the TEA+-intercalated tetratitanate compound was dispersed in massive amounts of distilled water to obtain the [Ti4O9]2ˉ nanosheets. The structures and morphologies of the ZnTiO3/TiO2 composite photocatalysts were investigated by using X-ray diffraction (XRD) and scanning electron diffraction microscopy (SEM). Furthermore, the photocatalytic activities of the synthesized ZnTiO3/TiO2 composite photocatalysts were also characterized. The experimental results revealed that the ZnTiO3/TiO2 composite photocatalyst obtained at the value of pH = 7.0 exhibits the higher photocatalytic activity.