Materials Chemistry and Physics, Vol.160, 251-256, 2015
A novel p-n heterojunction BiOBr/ZnWO4: Preparation and its improved visible light photocatalytic activity
A novel BiOBr/ZnWO4 p-n heterojunction catalyst was fabricated for the first time via a facile deposition method. The morphology and structure of the catalyst were characterized by SEM, TEM, HR-TEM, EDS, XRD, UV-vis DRS and BET. The results show that ZnWO4 nanoparticles conjugated firmly with BiOBr nanoplates with the crystal structure of monoclinic ZnWO4 and tetragonal BiOBr. The photocatalytic performance of the catalysts was evaluated through decolorization of rhodamine-B (RhB) in aqueous solution under visible light irradiation(lambda > 420 am). BiOBr/ZnWO4 heterojunction catalyst shows much higher photocatalytic activity than that of BiOBr and ZnWO4. 30% BiOBr/ZnWO4 heterostructure exhibits the highest photocatalytic activity with almost complete removal of RhB in 16 min. Moreover, good recyclability was also obtained from the BiOBr/ZnWO4 heterojunction catalyst. The enhanced photocatalytic efficiency of the BiOBr/ZnWO4 heterostructures may be related to the formation of p-n heterojunction interface between BiOBr and ZnWO4 which reduced the recombination of electrons and holes. (C) 2015 Elsevier B.V. All rights reserved.
Keywords:Inorganic compounds;Heterostructures;Composite materials;Energy dispersive analysis of X-rays