复合型CoO／TiO2光催化剂降解亚甲基蓝动力学研究

以钛酸四丁酯为前驱体，采用溶胶凝胶法，制备了CoO掺杂的TiO2光催化剂。利用X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）、紫外可见漫反射（UV—visDRS）对催化剂进行了分析、表征。以中压汞灯为光源，研究了亚甲基蓝（MB）在CoO／TiO2微粒水悬浮液中的降解动力学。结果表明：所制备的催化剂活性组分主要是锐钛矿型的二氧化钛和CoO固溶体，粒径为25～30nm，分布均匀。亚甲基蓝的光催化降解动力学满足一级动力学，在一定的浓度范围内，反应速率常数随初始浓度增大而减少，适当的掺钴量可以有效地提高TiO2光催化活性，其最佳掺杂量重量百分比为0．25％。

Research on kinetics of photocatalytic degradation of methylene blue （MB） by using CoO/TiO2 as composite photocatalyst

TiO2 photocatalyst doped with CoO was synthesized by sol-gel method using tetrabutyl titanate as recursor. The obtained samples were analyzed and characterized by X-ray diffraction （XRD） , scanning electron microscopy （SEM） , transmission electron microscopy （TEM） and ultraviolet visible diffuse reflectance （UV-vis DRS）. The kinetic of degradation of methylene blue （MB） in CoO/TiO2aqueous suspension was studied by u- sing medium pressure mercury lamp as an illuminating source. The results indicated that active ingredients of the photocatalyst were constituted by the solid solution of anatase titania and CoO. The particle with a uniform size （about 25 - 30 nm） reached nanometer level. The kinetic of the degradation of MB was accorded with the first- order reaction kinetic model. The reaction rate constant decreased with increasing the initial concentrations within a certain concentration range. A suitable CoO doping content could enhance the photocatalytic activation, and the optimum amount was 0. 25% in this research.