Anatase/Rutile Phase Control of Titanium Oxide Nanoparticles Synthesized from Potassium Titanium Oxalate by Homogeneous Precipitation and Hydrothermal Methods

Preparation conditions of titanium oxide (TiO2) powders were examined by the hydrolysis of titanium potassium oxalate (K2TiO(C2O4)2), through the homogeneous precipitation method (80oC for 24 h) and hydrothermal treatment (160 or 170oC for 1 h). According to the Rietveld analysis, almost a single phase of anatase TiO2 could be obtained by the hydrothermal treatment at 160oC for 1 h, followed by the heating at 900oC for 10 min in air. The molar ratio of anatase to rutile TiO2 was found to be controlled by optimizing the hydrothermal conditions in the solution and the heating conditions in air for the photocatalytic activity.