混晶型TiO_2/凹凸棒土纳米复合材料的光催化性能

Photocatalytic properties of mixed-phase TiO_2/attapulgite nanocomposites

以TiCl4和凹凸棒土（ATP）为原料制备了TiO2／ATP纳米复合材料，用XRD和TEM对所得样品进行了表征，并在紫外光下将此复合材料用于降解甲基橙。研究了溶液pH值、催化剂投料量、甲基橙初始质量浓度和反应时间等条件对甲基橙降解率的影响。XRD和TEM显示凹凸棒土的表面包裹着平均粒径约为10nm的混品型纳米二氧化钛。光催化实验结果表明，在pH值为1～4、纳米复合材料的投料量为1．0g／L、甲基橙初始质量浓度为0．01g，L和光催化反应时间为4h的情况下，甲基橙的降解率可达90％以上。

The TiO2/ATP nanocomposites were prepared by using attapulgite and TiCl4 as raw materials. The as-prepared samples were characterized by X-ray diffraction （XRD） and transmission electron microscopy （TEM）. The nanocomposites was also used for the photocatalytic degradation of methylorange under UV irradiation. The effects of pH value, dosage of nanocomposites, initial concentration of methyl orange and reaction time on photocatalytic degradation efficiency were investigated. XRD and TEM revealed that the surface of ATP is covered with mixed-phase titania particles, and the average size of nano-titania is about 10 nrn. The photocatalytie results show that the degradation rate of methyl orange can be maintained at more than 90%, when pH value is 1, the dosage of nanocomposites is 1 g/ L, initial concentration of methyl orange is 0.01g/L and reaction time is 4 hours.