膨胀石墨负载纳米TiO_2光催化剂的制备及对甲基橙溶液的吸附与光降解

Preparation of TiO_2-coated exfoliated graphite photocatalyst and its adsorption and photodegradation of methyl orange solutions

以钛酸丁酯为钛源,膨胀石墨为载体,采用溶胶-凝胶法成功地制备了膨胀石墨(EG)负载TiO2光催化剂(TEG),采用X射线衍射分析(XRD)、扫描电镜(SEM)、比表面积等分析技术对样品进行表征,以甲基橙为目标降解物,考察了热处理温度、负载次数、目标降解物浓度等不同条件下催化剂的光催化性能。结果表明,氧化钛以纳米颗粒的形式附着在膨胀石墨薄片表面,具有疏松多孔蠕虫状结构的膨胀石墨为氧化钛提供高浓度的三维降解环境,负载2次在500℃下经过3h热处理得到的催化剂在紫外光激发下对甲基橙溶液表现出较高的光催化活性。

TiO2-coated exfoliated graphite photocatalyst was successfully prepared with trtrabutyltitanate as precursor and exfoliated graphite （EG） as carrier via sol-gel method. The resulting samples were characterized by XRD,SEM and BET surface area. The performances of photodegradation of the samples were examined with methyl orange （MO） as a contaminant,the activities of photocatalysis of the samples were investigated with different heat-treatment temperatures, different coating times,and various of initial MO concentrations. The experimental results showed that TiO2 deposited on the flakes of EG in the forms of nanocrystalline. The worm-like exfoliated graphite provided a three dimensional environment for photocatalytic reaction. The photocatalyst coated two times, calcinated at 500℃ for 3h showed high photocatalytic reactivity under UV light irradiation in photodegradation of highly concentrated MO solutions.