Modification of titanium dioxide by solution plasma

A solution plasma approach for modification of phase and morphology of titanium dioxide is explored as complementary to the standard sol-gel method. Titanium dioxide powders with different proportions of anatase and rutile phases were successfully synthesized by solution plasma treatment and the photocatalytic activities investigated by solar irradiation of methylene blue. The plasma can facilitate not only the phase transition from anatase to rutile structure but also decrease of particle size significantly through a thermal shocking effect, resulting in shifting of energy bandgap from 3.2 to 3.0 eV. Degradation of methylene blue in the titanium dioxide is evident and amounts up to 50% drop in absorbance. Therefore, the solution plasma method is a new promising economic method for titanium dioxide to facilitate the phase transition and decrease of grain size compared to the traditional sol-gel method.