Solvothermal synthesis and photocatalytic property of N doped TiO₂ powders

Abstract

Nano-N doped TiO2 powders were synthesised with solvothermal processes. Four kinds of starting compositions were used for solvothermal syntheses of N doped TiO2 powders. The powders were characterised with XRD, SEM and spectrophotometry. The powder synthesised with titanium sulphate and diethylenetriamine has the highest N content of 17·4 mol.-%. The N content in the powder depends on the starting composition, in which the mechanism is discussed. N doping narrows the band gap of the powder and introduces indirect band gap to the powders, which respectively extend the absorption edge to visible light region and longer wavelength. The experiment of photodegradation on the synthesised powders indicated that the degradation rate of methyl orange increased with the light adsorption edge of the powder and the N content in the powder.