Graphene oxide-derived carbon-doped SrTiO3 for highly efficient photocatalytic degradation of organic pollutants under visible light irradiation

SrTiO3 is a promising photocatalyst for water splitting, dye degradation, and CO2 or NOx reduction; however, its practical applications are greatly limited because of its poor visible light absorption ability. Herein, we demonstrate a novel approach to introduce carbon doping in SrTiO3 through heat treatment of graphene oxide (GO) with hydrothermally synthesized SrTiO3. During the heat treatment, the carbon species diffused and were doped into the SrTiO3 lattice, while the residual GO sheets rolled up to form carbon nanotubes (CNTs). The carbon-doped SrTiO3-coupled CNTs exhibited increased visible light absorption, facile charge separation, and high unpaired electron density, enabling their application as efficient photocatalysts to degrade azo dyes and phenolic compounds including methyl blue, methyl orange, rhodamine B, phenol, and bisphenol A under visible light irradiation. This study introduces a novel strategy for the synthesis of carbon-doped SrTiO3 for environmental remediation derived from heat treatment of GO.