以棉花纤维为模板制备了银掺杂的TiO2中空纳米纤维光催化材料,利用热重分析(TG)、扫描电子显微镜(SEM)、X光电子能谱(XPS)、X射线衍射(XRD)、Zeta电位、紫外一可见光谱(UV-Vis)和傅立叶变换红外光谱(Fr-IR)等技术对该材料的形貌、晶体结构、银的状态等特性进行了表征.以亚甲基蓝(MB)的脱色降解为模型反应,考察了银掺杂的样品Ag/TiO2在不同光源下的光催化性能.结果表明,所制得的Ag/Ti02材料保留了棉花纤维的形貌,且表面带有大量的负电荷;该Ag/TiO2材料在太阳光条件下的光催化性能显著高于同条件下Ti02和同材料在紫外光条件下的,如Ag/Ti02在太阳光下1.5h可使MB溶液的脱色降解率在95%以上,在Ti02上2.5h时不足60%,低于Ag/Ti02上0.5h的结果;在紫外光条件下Ag/TiO2 3h时脱色降解率仅为35%.连续重复使用5次时Ag/Ti02仍能保证MB溶液的脱色降解率在90%以上;该纤维光催化材料易于离心分离去除、再利用.因此,以棉花为模板制备的Ag/Ti02中空纳米纤维催化材料是一种无能耗、无污染、高活性的绿色环保型光催化材料.
AgfFiO2 hollow nano-fiber photocatalytic material was successfully synthesized by using cotton fiber as the template. Thermogravimetric analysis (TG), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD), Zeta potential, UV-Vis and IR techniques were employed to characterize the morphology, phase structure and the state of silver. Using the decolorizing degradation of methylene blue (MB) as the model reaction, the photocatalytic property of the material Ag/TiO2 was investigated under different light sources. The results showed that the material not only copied the morphology of cotton fibers but also had negative charges on its surface. The sample showed much better photocatalytic property than pure TiO2 and its activity was higher under the sunlight than under UV irradiation. For example, on the surface of Ag/TiO2 hollow nano-fiber material, the decolorizing efficiency of MB solution was over 95% when irradiation time was 1.5 h under the sunlight while on TiO2, the efficiency was less than 60% when the time was 2.5 h, which was lower than the result of Ag/TiO2 when the time was 0.5 h. However, under UV irradiation, the efficiency was only 35% on the material Ag/TiO2 when the time was 3 h. Its photocatalytic activity didn't basically decrease and the efficiency was kept above 90% when it was repeatedly used for 5 times. The material was easily removed by centrifugal separation and used repeatedly. Therefore, Ag/TiO2 hollow nano-fiber material, synthesized by the template method, is no energy consumption, no pollution, good photocatalytic property and green environment-friendly catalytic material.