The synthesis of nano-TiO2 powder by sol-gel method and the phase transformation

Nanosized TiO2 powder with anatase and rutile structures was synthesized by a sol-gel method using TiCl4 ethanol solution as a precursor. The grain size of TiO2 powder was about 63nm after the precursor was calcined at 600degreesC for 2 hours. The experimental techniques of XRD, TEM and Particle Distribution were used to characterize the synthesized specimens. Various special effects were investigated for their contribution to crystal structure and the size of TiO2 powder. The formation of anatase as well as the rutile phase of TiO2 was indicted from the XRD when the reaction temperature was above 30degreesC and when the sol was irradiated by infrared rays. However, an anatase TiO2 powder formed after the heat treatment of the dried gel in a temperature range from 300degreesC to 500degreesC. Under the vacuum drying and with the calcined time below 3hours, the anatase phase was gained. As well as with the increase of gelatinizing time, the anatase TiO2 powder was obtained.