树叶为模板网状TiO_2的制备及其光催化性能

Preparation and Photocatalytic Properties of Reticular TiO2 by Leaf Template Method

采用模板法与溶胶-凝胶法相结合的方法,以羽状网脉的洋槐树叶为模板制备出网状的二氧化钛光催化材料.利用红外光谱仪(FT-IR)、扫描电子显微镜(SEM)、能量色散型X射线光谱仪(EDX)、X射线衍射仪(XRD)对样品的表面形貌、成分和晶型进行表征,以甲基橙的脱色降解为模式反应,考察了宏观形貌对TiO2光催化性能的影响.结果表明:以树叶为模板制得的TiO2,呈网状结构,网孔直径约为5～10μm,且有少量直径约为2～3μm规则球形和直径约5μm管状的TiO2;当pH=3时,网状TiO2在3h内对甲基橙的降解率分别比粉末TiO2高37.2%,比商品粉末TiO2高44.6%,且重复使用4次后,降解率仍能保持在90%以上,明显优于粉末TiO2,同时为制备其它形貌的TiO2提供一种新思路.

Combining the template method and sol-gel method, the reticular TiO2 photocatalytic materials were prepared by using the pinnate vein leaves of Sophora japonica L. as the template. The surface morphology, components and crystal characterization of the samples obtained under different conditions were characterized by FT-IR, SEM, Energy Dispersive X-Ray Fluorescence Spectrometer （EDX） and X-ray diffractometry （XRD）. By the methyl orange （MO） degradation as a model reaction, the effect of the macroscopic morphology on the photocatalytic properties of TiO2 was investigated. The results indicated the prepared TiO2 was reticular and its diameter was 5～10 μm, and even there were a few regular spherical TiO2 with diameter 2～3 μm and microtubule TiO2 with diameter 5 μm. For pH=3, the MO degradation rate by the reticular TiO2 in 3 h was higher by 37.2%, 44.6% than that of TiO2 powder and commercial TiO2 powder, respectively. And the degradation rate could keep more than 90% when it was repeatedly used for 4 times. And this paper introduced a new idea to prepare various morphological TiO2.