Facile synthesis of nitrogen-doped titanium dioxide with enhanced photocatalytic properties

Abstract

TiO2 precursor was synthesized by sol-solvothermal method with tetrabutyl titanate as the titanium source. Then the nitrogen doping was conducted on using hydrazine hydrate as the nitrogen source by hydrothermal method. Compared with P25, the obtained TiO2 and N-doping TiO2 both exhibited excellent photocatalytic performance in degrading methyl orange dye, which were 1.85 and 1.86 times that of P25. The higher photocatalytic efficiencies of TiO2 and N-doped TiO2 are related to their smaller particle sizes (14.5 and 10 nm) and abundant pore structure. Furthermore, XPS results have demonstrate the substitutionary and interdoping of nitrogen in TiO2 lattice. Accordingly, nitrogen doping did not only maintain the crystal structure of anatase TiO2 along with changing the band gaps, but also induced the occurrence of oxygen vacancies and Ti3+ to reduce the recombination rate of electron-hole pairs. Therefore, N-doped TiO2 displayed the highest degradation rate of 99.7%.