Visible-light-driven photocatalytic S- and C- codoped meso/nanoporous TiO2

Abstract

The first facile and efficient soft synthesis for fabricating S- and C- co-doped hierarchically meso/nanoporous TiO2 is hereby presented. The doping of sulfur is achieved through a counter strategy, in which the precursor of TiO2 is added to the sulfur hydrosol. The sulfur nanoparticles in the sulfur hydrosol serve as the seeds for the formation of bimodal meso/nanopores TiO2 upon calcination treatment. The prepared anatase TiO2 exhibited excellent thermal stability and photocatalytic activity. In comparison to commercial P25 TiO2, our S- and C- codoped meso/nanoporous anatase TiO2 exhibits remarkably enhanced visible light-driven photocatalytic activity on the decomposition of methylene blue (MB). The samples also showed excellent cyclic stability in the photocatalytic activity of degrading MB. The formation mechanism of these S-, C- codoped hierarchically meso/nanoporous TiO2 spheres is also discussed. The high photocatalytic activity in the visible light region is attributed to numerous oxygen vacancies, acidic sites on the surface of TiO2, and large specific surface area.