中文摘要：

通过分步沉积法制备了不同Zr／Ti摩尔比的锶锆钛（SZT）复合氧化物催化剂，以X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）、紫外-可见（UV-Vis）漫反射光谱等表征手段考察不同Zr／Ti摩尔比下SZT催化剂的结构形态，以可见光下光催化降解亚甲基蓝为模型反应考察样品的光催化活性．结果表明：Zr／Ti摩尔比〈l时SZT催化剂发生Zr4＋与Ti4＋同质替换，引起晶格缺陷，光催化活性小幅提高Zr／Ti摩尔比≥1时SZT催化剂产生SrzrO3/TinO2n-1（n=4，9）的新晶相，TinO2n-1（n=4，9）的存在有利于光生电子-空穴的传导与分离，可大幅提高催化剂光催化活性，其中，SZT-5/5表现出最高的光催化活性，其～级反应速率常数达到0．2133min-1，是同等光照条件下纯SrTiO3样品（O.0158min-1）的13．5倍．

英文摘要：

A series of Sr-Zr-Ti （SZT） mixed oxide catalysts were prepared by a fractional-precipitation method. These photocatalysts were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM）, transmission electron microscope （TEM）, and ultraviolet visible （UV-Vis） diffuse reflectance absorption spectra. Photocatalytic degradation of methylene blue was investigated to determine the photoactivity of the catalyst. It was shown that with a Zr/Ti ratio〈l, the SZT mixed oxide catalysts showed improved photocatalytic activity. This was attributed to lattice defects creating active photocatalytic sites because of Zr4＋ doping. For Zr/Ti ratios〉l, the catalysts showed markedly improved photocatalytJc activity because of new crystalline phases of SrZrO3 and TinO2n-1 （n=4, 9） that facilitated splitting and conduction for electron/hole. Typical SZT samples （Zr/Ti=4） showed the highest photocatalytic activity, with first-order reaction rate constant 13.5 times that of a SrTiO~ sample.