Characterization of natural sphalerite as a novel visible light-driven photocatalyst

Natural sphalerite (ZnS), as a visible light-induced photocatalyst, was characterized by X-ray diffractometry (XRD), electron microprobe analysis (EMPA), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS) and zeta-potential analysis. Its photoactivity was tested and compared with pure sphalerite by methyl orange (MO) photoreduction. The isomorphous substitution and other defect states in natural sphalerite altered the band structure and surface properties, resulting in different photoactivity. The results showed 98.74% MO was photoreduced by natural sphalerite after 2 h visible light irradiation. Our study indicated that natural sphalerite might be suggested as a new cost-effective and solar light-responsive photocatalyst. (c) 2008 Elsevier B.V. All rights reserved.