掺银二氧化钛的超声化学法制备与光催化性能研究

Ultrasonic Chemical Synthesis and Properties of Ag-doped Titanium Dioxide

采用超声化学法在制备纳米二氧化钛的过程中直接掺加金属离子 ,制备出掺有银的纳米二氧化钛 ,其晶型为金红石型 ,其中存在氯化银晶粒。采用XRD、TEM和SAED等测试手段对所制备的二氧化钛样品进行表征。样品为长柱状 ,粒度大小约为 3/ 12nm(W/L) ,晶粒间相互取向连生 ,聚集形成羽状枝蔓晶。以甲基橙和活性艳红作为探针分子研究样品的光催化性能 ,发现所制备的掺银二氧化钛可以明显地提高对活性艳红的光催化能力 ,而对甲基橙的催化性能提高不大。对超声波作用下纳米二氧化钛的形成机理进行了讨论。

A new ultrasonic chemical method to directly prepare Ag-doped nanocrystalline TiO 2 has been established. TiO 2 particles were synthesized by the hydrolysis of TiCl 4 under high-intensity ultrasonic irradiation at 70?℃ for 3?h. Characterization was accomplished using various different techniques, such as powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electronic diffraction (SAED) and so on. The TEM images showed that the particles of TiO 2 were columnar in shape and the average size was about 3/12?nm(W/L).The particles were linked together each other at the certain principle, forming the shape like dendrite crystal. The formation mechanism of TiO 2 crystal under high-intensity ultrasonic irradiation was also discussed. The crystal structure of products was depended upon the polymerized form of Ti 4+ in solution. The photo-catalytic activity of Ag-doped titanium dioxide samples was evaluated using the photo-oxidations of methyl orange and reactive brilliant red as test reactions.