{040/110} Facet Isotype Heterojunctions with Monoclinic Scheelite BiVO₄

Controlling the phase, crystallinity, and microstructure and fabricating a facet isotype heterojunction with a proscribed reduction–oxidation facet exposure factor have a strong constructive effect toward photoexciton separation and migration. In this respect, here diverse synthetic courses such as calcination (BiVO 4 -C), hydrothermal treatment (BiVO 4 -H), and a reflux method (BiVO 4 -R) are introduced to fabricate various hierarchical morphologies of highly crystalline monoclinic scheelite bismuth vanadate (BiVO 4 ) with different redox facet exposure factors that have been well established by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy analysis. The analytical and experimental investigations revealed superior photocatalytic upshots of a BiVO 4 -R {040/110} facet isotype heterojunction toward levofloxacin (LVF) detoxification (71.2%, 120 min) and the water oxidation reaction (530.6 μmol, 120 min) relative to BiVO 4 -C (42.3%, 434.2 μmol) and BiVO 4 -H (60.4%, 494.8 μmol). Accordingly, the BiVO 4 -R {040/110} facet isotype heterojunction (145.6 μA/cm 2 ) expressed an enhanced photocurrent in comparison to pristine BiVO 4 -C (75.5 μA/cm 2 ) and BiVO 4 -H (113.1 μA/cm 2 ). The superior photocatalytic redox efficiency was attributed to well-exposed {040} reduction and {110} oxidation facets and a superior relative {040} facet exposure factor provoking an enhanced charge carrier separation over a BiVO 4 -R {040/110} facet isotype heterojunction. The spatial exciton separation over the BiVO 4 -R sample was well established by numerous analytical and experimental investigations. The effectual associations among physicochemical, photoelectrochemical properties, {040/110} facet isotype heterojunction, relative reduction–oxidation facet exposure factor, and photocatalytic performances of fabricated BiVO 4 microstructures were well established, and the upshots of this research were discussed finely. The research signifies an effectual direction for morphology and relative reduction–oxidation facet exposure factor controlled fabrication of facet isotype heterojunction based materials for superior photocatalysis and could be advantageous for supplementary research areas.