喷雾热解法制备非晶型TiO_(2)@Ag/AgBr复合光催化剂的性能

Performance of amorphous TiO_(2)@Ag/AgBr composite photocatalyst prepared by spray pyrolysis

以TiCl4为前体,通过喷雾热解法制备出非晶型TiO_(2);以AgNO_(3)为银源,采用水包油自组装法合成TiO_(2)@Ag/AgBr复合光催化剂。利用X射线衍射仪和X射线光电子能谱仪分析了样品的微观结构和价态,采用扫描电镜和透射电镜观察了样品的表面形貌,使用紫外可见漫反射光谱仪、荧光光谱仪和电化学阻抗谱对样品的光吸收范围和电子复合行为进行表征。通过在自然光照条件下降解甲基橙的实验研究了复合材料的光催化性能,并探讨了不同Ag/AgBr负载量对光催化性能的影响。结果表明:制备的TiO_(2)为直径小于500 nm的非晶型纳米级球形颗粒,Ag/AgBr均匀的负载在其表面。制备的TiO_(2)@Ag/AgBr复合光催化剂均表现出良好的光催化活性,其中最佳负载量的TiO_(2)@Ag/AgBr复合光催化剂对甲基橙降解效率可达到91%。

Amorphous titanium dioxide was prepared by spray pyrolysis using TiCl4 as the precursor,and the TiO_(2)@Ag/AgBr composite photocatalyst was synthesized by the oil-in-water self-assembly method with AgNO_(3) as the silver source.The microstructure and valence state of the samples were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy.The surface morphology of the samples was observed by scanning electron microscope and transmission electron microscope.The light absorption range and electronic recombination behavior of the samples were characterized by UV-Vis diffuse reflection spectrometer,fluorescence spectrophotometer,and electrochemical impedance spectroscopy.The photocatalytic performance was studied by degrading methyl orange under the natural light conditions,and the effect of Ag/AgBr loading capacity on the photocatalytic performance was discussed.The results show that,the prepared titanium dioxide is an amorphous nano-scale spherical particle with the diameter of less than 500 nm.Ag/AgBr is uniformly loaded on the TiO_(2) surface.The prepared TiO_(2)@Ag/AgBr composite photocatalysts all show the good photocatalytic activity.The degradation efficiency of methyl orange by the TiO_(2)@Ag/AgBr composite photocatalyst with the best loading capacity can reach 91%.