Ex Situ Method for Photoreduction of the Cadmium Ion from Terbium-Loaded Bismuth Vanadium Oxide.

The photoreduction of Cd (II) to Cd (0) was performed using BiVO, which was tremendously enhanced by Tb-doped BiVO. The relationship between charge carrier isolation and light harvesting was studied in depth in this research, and a promising technique for fabricating effective photocatalysts for heavy metals was discovered. Lattice disorder effects due to size variance between V and Tb cations in BiVO nanomaterials substituted with an invariable Tb cation at different concentrations ( = 15, 20, and 25%). BiVO and 15% Tb/BiVO evidenced a coexistence of monoclinic (α-phase) with a symmetry, while 25% Tb/BiVO was tetragonal (γ-phase) with an 4/ symmetry. Raman scattering experiments elucidated the changes in BiVO lattice corresponding to oxygen motion, suggesting significant destabilization of the VO tetrahedra after addition of Tb. The SEM micrograph depicted a disparity in the microstructure with reduced grain size in 25% Tb/BiVO samples. However, the TEM micrographs of 25% Tb/BiVO nanomaterials revealed that crystallite sizes of 25-35 nm were obtained, presenting a single tetragonal phase, highly homogeneous in nature. Impedance spectroscopy was used to study the conductivity of these compounds in the temperature range of 300 °C. At 300 °C, the compounds with = 25% showed a conductivity of 15.92 S cm. The conductivity values were found to be comparable with the highest values reported in the literature for similar compounds.