Methyl orange degradation over a novel Bi-based photocatalyst Bi3SbO7: Correlation of crystal structure to photocatalytic activity

Bi3SbO7 was synthesized by a solid state reaction method and the as-synthesized powder was characterized by X-ray diffraction (XRD) and UV-vis diffuse reflectance spectrum. The photocatalytic activity of Bi3SbO7 was evaluated by means of the degradation of methyl orange; the effects of photocatalyst concentration, pH and wavelength of irradiation upon photocatalytic performance were investigated. The photocatalytic character of Bi3SbO7 was discussed in terms of band structure and crystal structure. The results obtained reveal that Bi3SbO7 has an intrinsic optical band gap of 2.71 eV and can photocatalytically respond to light upto similar to 600 nm. Generally, Bi3SbO7 shows better photocatalytic activities than BiVO4 under both UV and visible light because of the lower packing factor and correspondingly higher structural openness of Bi3SbO7. (c) 2007 Elsevier Ltd. All rights reserved.