Preparation of TiO₂ by Sol-gel Method and Its Photocatalytic Properties

As an environment-friendly catalyst,titanium dioxide(TiO₂) plays an important role in photocatalysis.In this paper,TiO₂ powder was prepared by sol-gel method without stirring,using butyl titanate(TBT) as the titanium source.The crystal structure,morphology and absorbance of the samples were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and ultraviolet-visible spectroscopy(UV-Vis),respectively.The results show that the phase of the samples changes from anatase to rutile with increase in calcination temperature,combined with the morphology variation.The sample roasted at 400℃ shows peanut-like morphology,and the irregular shapes appear at 500℃.The rutile phase begins to appear at 600℃.At the calcination temperature of 700℃,all the phases transfer into rutile with irregular morphology.Using methyl orange as the simulated wastewater,the degradation ability of the samples was investigated under ultraviolet irradiation.The best photocatalytic property can be obtained with the sample calcinated at 400℃,leading to 91% of degradation rate for methyl orange at 80 min of illumination.