Facile synthesis of hierarchically structured BiVO4 oriented along (010) facets with different morphologies and their photocatalytic properties

Hierarchically structured BiVO4 oriented along (010) facets with different morphologies are synthesized by a template-free solvothermal process in glycerol (Gly)-water mixed solvent. The effects of the volume fraction of Gly aqueous solution on the crystal structure, growth degree of (010) facets, morphology and photocatalytic activity were investigated. It is found that the volume fraction of Gly aqueous solution has strong influence on the concentration of the reaction species in the self-assembly process, and consequently induces the different morphology, as well as the crystal growth of the as-prepared BiVO4 oriented along (010) facets. A possible formation mechanism is proposed on the basis of the characterization results of X-ray diffraction and scanning electron microscopy. The four-leaved primrose-like BiVO4 sample exhibits the best photocatalytic activity for the photodegradation of methylene blue (MB) solution under simulated sunlight irradiation. The enhanced photocatalytic activity can be attributed to the improved separation of photogenerated electrons and holes caused by both special morphology and preferential growth of (010) facets. (C) 2016 Elsevier B.V. All rights reserved.