钛酸纳米管前驱体水热制备TiO_2:水热媒介对结晶度及光催化活性的影响

Hydrogen Titanate Nanotubes as Precursor to TiO_2 Preparation:Influence of Hydrothermal Media on Crystallinity and Photocatalytic Activity

以钛酸纳米管为先驱体,180℃24 h同一水热条件下,利用H2O、HNO3、KBF4以及HNO3+KBF4的4种水热媒介溶液,制备了高结晶度高光催化活性的TiO2,并研究了水热媒介对TiO2结晶度、表面羟基和光催化活性的影响。通过扫描电镜(SEM)、X射线衍射(XRD)、红外测试(FTIR)、X射线光电子能谱(XPS)、紫外可见漫反射吸收光谱(UV-Vis)进行了结构表征。光催化活性通过降解甲基橙溶液进行了评价。结果表明,与其他3种媒介相比,HNO3+KBF4溶液为水热媒介制备的锐钛矿晶型TiO2,结晶度高,表面羟基含量高,因此,呈现高的光催化活性。

TiO2 with high crystallinity and high photocatalytic activity was prepared in hydrothermal media of H2O,HNO3,KBF4 and HNO3 ＋ KBF4 solutions,respectively,under 180 ℃ for 24 h using hydrogen titanate nanotubes as the precursor.The influence of hydrothermal media on crystallinity,hydroxyl group content and photocatalytic activity of the obtained TiO2 was studied.The structures were characterized by SEM,XRD,FTIR,XPS,UV-Vis diffuse reflectance absorption spectroscopy（UV-Vis DRS）.The photocatalytic activity was evaluated by photocatalytic degradation of methyl orange.The results show that the anatase TiO2 prepared in HNO3＋KBF4 hydrothermal medium has higher crystallinity,more hydroxyl group thus higher photocatalytic activity comparing with that of anatase TiO2 obtained from other three hydrothermal media.