TiO2-ZnO复合中空微球的制备及光催化性能

以Ti（SO₄）₂和Zn（NO₃）₂为原料，采用水热法制备TiO₂-ZnO复合中空微球光催化剂。通过FTIR、XRD、SEM、紫外可见漫反射光谱（UV-Vis DRS）、XPS及N₂吸附-脱附等方法对TiO₂-ZnO复合光催化剂的结构和性能进行表征，并以亚甲基蓝（MB）为目标降解物，评价TiO₂-ZnO复合中空微球光催化活性。结果表明，TiO₂-ZnO光催化剂具有中空微球结构，粒径为1~2 μm，比表面积为30.46 m2/g。TiO₂的加入可提高ZnO对光的吸收，有效降低电子空穴复合率。在高压Hg灯照射下，TiO₂-ZnO复合中空微球的光催化性能均高于纯ZnO，其中Zn（NO₃）₂与Ti（SO₄）₂摩尔比为1:0.7条件下制备的TiO₂-ZnO复合中空微球样品表现出较好的光催化活性，光照60 min，对MB的降解率可达95.8%，其光催化降解速率是纯ZnO的4.3倍。 

Preparation and photocatalytic properties of TiO2-ZnO composite hollow microspheres

The photocatalysts of TiO₂-ZnO composite hollow microspheres were obtained by using Ti(SO₄)₂ and Zn(NO₃)₂ as raw materials through hydrothermal method. The structures and properties of as-prepared TiO₂-ZnO samples were characterized by FTIR, XRD, SEM, UV-Vis diffuse reflection spectrum (UV-Vis DRS), XPS and N₂ adsorption-desorption analysis. Methylene blue (MB), as a photocatalytic degradation target, was used to evaluate the photocatalytic performance of the prepared photocatalysts. The results show that the prepared TiO₂-ZnO photocatalyst has a hollow microsphere structure with a particle size of 1-2 μm and a specific surface area of 30.46 m²/g. The light absorption ability of ZnO is improved by the addition of TiO₂ and reduces the electron hole recombination rate effectively. Under high pressure Hg lamp irradiation, the photocatalytic activity of TiO₂-ZnO composite hollow microspheres is higher than that of pure ZnO, and the TiO₂-ZnO sample with Zn(NO₃)₂:Ti(SO₄)2 molar ratio of 1:0.7 has the best photocatalytic activity among all the samples. The degradation rate of MB can reach 95.8% in 60 min, and the photocatalytic degradation rate of TiO₂-ZnO composite hollow microspheres is 4.3 times that of ZnO.