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.