载银TiO2/沸石催化剂的制备、表征以及光催化性能的研究

为获得高活性的负载型TiO2光催化剂，通过硝酸银溶液浸渍-紫外光照的方法获得载银的TiO2/沸石催化剂.银改 性的TiO2/沸石催化剂光催化性能较改性前大大提高.最佳硝酸银浸渍液浓度为10-3mol/L,此时该催化剂的光催化性能接 近纳米TiO2粉末（Degussa P25）,但进一步升高硝酸银浸渍液浓度，光催化性能又降低.实验通过X-射线衍射（XRD）和 透射电镜（TEM）对载银TiO2/沸石催化剂的表征,结果表明,金属银对电子的捕获使得电子-空穴对有效分离， 从而使银 改性光催化剂的活性提高.

Preparation, characterization and photocatalytic activity of silver-modified TiO2/zeolite catalysts

In order to obtain supported photocatalysts with high activity,silver-modified TiO_2/zeolite catalysts were prepared by AgNO_3 dipping followed by UV irradiation.The silver modified TiO_2/zeolite catalysts showed more enhanced photocatalytic efficiency than non-silver modified TiO_2/zeolite catalysts.The optimum silver nitrate concentration of the dipping solution was found to be 10~(-3) mol L~(-1),whose photodegradation efficiency approached that of titanium dioxide powder(Degussa,P25),but when the Ag~ concentrations increased further, the catalytic efficiency of the silver-modified catalysts decreased.Silvermodified catalysts were characterized by X-ray diffractometer(XRD) and transmission electron microscopy(TEM).The results indicate that the presence of metallic silver always produces an increase in catalytic activity,possibly because of the increase in the electron-hole pair separation efficiency induced by trapping of electrons by metallic silver.