Combined experimental and first principles look into (Ce, Mo) doped BiVO4

Abstract

Here we investigated the effects of Ce and Mo doping on hydrothermally synthesized bismuth vanadate BiVO4 nanoparticles (NPs). The existence of monoclinic scheelite and tetragonal zircon phases of NPs was validated from Rietveld refinement of the powdered X-ray diffraction, room temperature Raman, and Fourier-transform infrared spectroscopy. The co-doping of Bi and V sites with respective Ce and Mo dopants in a mixed tetragonal zircon and monoclinic scheelite phases of BiVO4 lattice was corroborated from high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. The photoluminescence measurements revealed enhancement of photo-generated carrier recombination in (Ce, Mo) co-doped BiVO4 NPs which may have hampered its photocatalytic efficiency in degrading the methylene blue dye. The simulations based on Hubbard U corrected density functional theory (DFT+U) suggest that Mo and Ce co-doping introduced deep impurity states which may have facilitated the photo-generated carrier recombination detrimental to photocatalytic performance. The UV-vis diffuse reflectance measurements provided evidence for the presence of these defect states. In summary, this work may have presented a comprehensive experimental analysis of (Ce, Mo) doped BiVO4 supported by DFT simulations.