Session: General Catalysis:

Transition metal tungstates are promising low-cost semiconductor nanomaterials that are photocatalytically active. CoWO₄, NiWO₄, CuWO₄, and ZnWO₄ were synthesized under similar conditions and characterized by dynamic light scattering, transmission electron microscopy, X-ray diffraction, and X-ray fluorescence. Photocatalytic performance was tested in photodegradation of methylene blue in water at 375±5 nm. The rates of the photodegradation of the dye were quantified via UV-visible spectroscopy. Introduction of low or high concentrations of dopants affects the electronic structure of the semiconductors and photodegradation rate. We also show band structures calculated within VASP to investigate the electronic effects of doping and the nature of the valence band edge and conductance band edge. Calculations were performed under the PBEsol+U framework to reproduce the expected band structure with single point HSE06 calculations to validate our results when possible.

UV-Vis time series of methylene blue photodegradation

UV-Vis time series of methylene blue photodegradation

Density of States of NiCo(WO<sub>4</sub>) <sub>2</sub> calculated within PBEsol+U

Density of States of NiCo(WO₄) ₂ calculated within PBEsol+U

Tristan G Maxson

Ball State University

Appearances