Effects of V doping and calcination temperature on the phase evolution of Ti-V-O nanoparticles synthesized by coprecipitation method

Abstract

Ti-V-O nanoparticles were produced by coprecipitation process using TiCl4 and VOCl3 as starting materials. The precipitates were calcined into different phases of a mixture of Ti-V-O oxides. The effects of V content and calcination temperature (500∼700°C) on the phase transition of the mixture of crystalline Ti-V-O oxides were studied. Increasing V addition and calcination temperature promotes the transformation of Ti-V-O oxides from anatase to rutile phase. Based on TG/DTA analysis, the reduction from V5+ to V4+ was observed in the V-rich samples at 730°C. The V5+ may exist as the form of V2O5 homogeneously dispersed within crystalline of TiO2, while V4+ is possible in the octahedral lattice of TiO2. A significant portion of vanadium ions can be incorporated at 730°C into TiO2 lattice resulting in rutile Ti1−xVxO2 solid solution formation.