Nitrogen-doped SiO2/TiO2 core/shell nanoparticles as highly efficient visible light photocatalyst

Nitrogen-doped SiO2/TiO2 core/shell nanoparticles with uniform diameter were fabricated using SiO2 template sol-gel method. Furthermore, the relationship between the temperate of calcination and photocatalytic efficiency was also investigated in the viewpoint of organic pollutant decomposition. The morphology and characteristics of nitrogen-doped SiO2/TiO2 core/shell nanoparticles were studied by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), X-ray powder diffraction (XRD), and specific surface area. The results demonstrated that nitrogen-doped TiO2 layer was successfully coated onto the SiO2 nanoparticles without aggregation. Nitrogen-doped SiO2/TiO2 core/shell nanoparticles exhibited highly efficient photocatalytic activity under visible light irradiation due to high nitrogen doping level and surface area. (C) 2009 Elsevier B.V. All rights reserved.