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Updated: Feb 3, 2026
08:23
Niobium Oxide Films Deposited by Reactive Sputtering: Effect of Oxygen Flow Rate
Published on: September 28, 2019
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Niobium Doping in BiVO4 : Interplay Between Effective Mass, Stability, and Pressure
Hori Pada Sarker1, Pratap M Rao2, Muhammad N Huda1
1Department of Physics, University of Texas at Arlington, Arlington, Texas, 76019, USA.
Summary
Niobium (Nb) doping in bismuth vanadate (BiVO4) enhances photocatalytic activity by altering electronic structure and effective mass. External pressure further improves photoconduction by inducing structural changes.
Area of Science:
- Materials Science
- Solid-State Physics
- Computational Chemistry
Background:
- Bismuth vanadate (BiVO4) is a promising photoanode material for water splitting.
- Understanding doping effects and external stimuli is crucial for optimizing BiVO4 performance.
Purpose of the Study:
- Investigate the impact of niobium (Nb) doping on BiVO4 electronic structure.
- Determine the effect of external pressure on Nb-doped BiVO4.
- Identify optimal doping strategies and conditions for enhanced photocatalysis.
Main Methods:
- Density Functional Theory (DFT) calculations.
- Analysis of chemical-potential landscape for phase stability.
- Study of electronic band structure and effective mass.
- Examination of local structural distortions.
Main Results:
- Nb doping, especially at V and Bi sites, is favorable and increases electron effective mass by 20% due to Nb 4d bands.
- Oxygen vacancies influence Nb dopability.
- External pressure modifies the stability zone and induces symmetrization of BiO8 polyhedra.
- Pressure-induced structural changes further reduce electron effective mass.
Conclusions:
- Nb doping significantly enhances catalytic activity of BiVO4 by modifying electronic properties.
- External pressure offers a route to further improve photoconduction in Nb-doped BiVO4.
- Simultaneous Nb substitution at V and Bi sites is most effective for performance enhancement.
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