In situ doping of carbon and sulfur from multifunctional agents to TiO2 nanospheres in water–acetone mixed solvent

Abstract

A novel strategy allowed the synthesis of carbon and sulfur codoped TiO2 nanospheres from multifunctional agents: Ti(SO4)2 as Ti source and sulfur donor, polyvinyl pyrrolidone (PVP) as surfactant and carbon donor. Ti(SO4)2 nanospheres precipitated in water–acetone mixed solvent. In situ doping of S to TiO2 was achieved when Ti(SO4)2 nanospheres transformed to TiO2 nanospheres during solvothermal process. PVP was firstly coated on the surface of the Ti(SO4)2 nanospheres and successively combined with the TiO2 nanospheres. PVP decomposed during the calcinations and carbon was further doped to the TiO2 nanospheres. The codoped TiO2 nanospheres had an average diameter of 70nm and highly porous structure. The final products exhibited significant red shift of the light absorption edge in comparison with that of the Degussa P25. These results demonstrated that doped TiO2 can be synthesized from reactants or surfactants containing doped elements without additional dopants.