TiO2-rGO制备及其对亚甲基蓝溶液的降解

本实验用改进的Hummers法制备氧化石墨烯(GO),通过溶胶-凝胶法制备得到TiO2-石墨烯复合材料(TiO2-rGO),研究了不同制备条件对复合材料光催化性能的影响。采用X射线衍射(XRD),拉曼光谱(Raman),比表面积(BET),扫描电镜(SEM),透射电镜(TEM)、紫外-可见(UV-Vis)吸收光谱和荧光光谱(PL)等测试手段对复合材料进行表征。结果表明,TiO2-rGO复合材料中的TiO2为锐钛相,且能均匀附着在石墨烯片层上,呈现层状堆积结构;与纯TiO2相比,复合材料具有较大的比表面积和更高的可见光响应。研究了该复合催化剂在紫外光下对亚甲基蓝以降解效果。当焙烧温度为450℃、TiO2/GO质量比为125:1时,制备得到的TiO2-rGO具有最优的光催化效果。

Preparation and application of TiO2-rGO in photocatalytic degradation of methylene blue solution

In this study,graphene oxide (GO) was prepared from natural flake graphite by the modified Hummers method. Graphene/TiO2 hybrid photocatalyst was successfully synthesized through a simple sol-gel method using TBOT (Ti(OC4H9)4) as Ti source. To study the effect of different preparation conditions on the photocatalytic properties of TiO2-graphene composite materials (TiO2-rGO), the prepared catalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, Brunauer-Emmett-Teller sorption (BET), scanning electron microscopy (SEM), transmission electron microscopy(TEM), UV-vis absorbance spectroscopy (UV-Vis) and fluorescence spectra (PL). The as-formed TiO2 was formed in anatase phase, and can be uniformly deposited on the graphene sheet, showing the layered structure of stacked. The composite material had a large specific surface area and higher visible response comparing to pure TiO2. The photocatalytic activity of the as-prepared products was evaluated by photocatalytic decolorization of methylene blue aqueous solution at ambient temperature under ultraviolet. The experimental results indicated that TiO2-rGO composite prepared with TiO2/GO mass ratio of 125:1 at calcination temperature of 450℃ had the greatest photocatalytic effect.