Synthesis, growth mechanism and photoelectrochemical properties of BiVO4 microcrystal electrodes

BiVO4 films were deposited on fluorine-doped tin oxide substrates by chemical bath deposition. The samples were characterized by an x-ray diffractometer, UV-Vis transmission spectra and a scanning electron microscope. The morphologies of the samples were adjusted by the deposition time, temperature, pH of solution and buffer solution. When the temperature and pH value of the solution were high, the polyhedron microcrystal of BiVO4 exposed fewer less planes on the surface and the films were more compact. On the basis of the experimental results, a possible growth mechanism was proposed. Moreover, the photoelectrochemical properties of the samples with different morphologies were investigated. The results suggested that the compact films with a smaller microcrystal exhibited better performance, which was helpful to understand the relationship between the morphologies of other microcrystal electrodes and their photoelectrochemical properties.