Crystallization of Nano TiO_2 Prepared by Adsorption Phase Reaction Technique and Photo-degradation of Gaseous Toluene

The crystallization of nano TiO2 prepared by adsorption phase reaction technique and the influence of crystallization on photo-catalytic activity of TiO2 were explored. XRD was employed to study the change of crystalline form and gain size of TiO2 under different sintering temperatures and times. The results indicated that there was also pure anatase TiO2 in samples, even when the sintering temperature reached 900 ℃. With increase of sintering temperature, grain size of TiO2 was below 7 nm and changed little. Whereas the peak area of anatase TiO2 increased with sintering temperature and remained unchanged when temperature reached 700 ℃. However change of sintering time influenced little on crystalline form and grain size of TiO2, so its photo-catalytic activity also changed little with sintering time increasing. Photo-degradation of gaseous toluene indicated that the sample sintered under 700 ℃ had the highest photo-catalytic activity and its activity was better than P25.