Electronic Structure Study of BiVO4 in Different Crystalline Phases via Density Functional Theory (DFT) Using the Quantum ESPRESSO Software: Comparison Between PBE and PBE+U Functionals

• Grant number: 26/14307-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2026
• End date: August 31, 2027
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Renato Vitalino Gonçalves
• Grantee: Luís Filipe Evangelista de Oliveira
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 24/00989-7 - Research Center of Molecular Engineering for Advanced Materials (CEMol), AP.CEPID

Abstract

Bismuth vanadate (BiVO4) stands out as one of the most promising materials for photoelectrocatalysis (PEC) applications, especially for the water oxidation reaction, which is the slowest and rate-limiting step in the overall water-splitting process. This material exhibits favorable properties, such as an appropriate band gap in the visible region, good chemical stability in aqueous media, and suitable energy band alignment for oxidation processes. However, its electronic properties are strongly dependent on the crystalline phase, which directly impacts its photoelectrocatalytic performance, making a detailed understanding of the relationship between crystal structure and electronic behavior essential. In this project, a theoretical study based on first-principles calculations is proposed, using Density Functional Theory (DFT) through the Quantum ESPRESSO software package, aiming to investigate the electronic structure of BiVO¿ in its main crystalline phases: monoclinic scheelite (ms), tetragonal scheelite (t-s), and tetragonal zircon (t-z). The band structure and density of states (DOS) will be analyzed, with emphasis on the contribution of the relevant electronic orbitals. The PBE and PBE+U exchange-correlation functionals will be employed, allowing the evaluation of the effects of the Hubbard correction on the description of the electronic states, especially those associated with the V 3d orbitals. It is expected that this study will provide a more accurate description of the band gap and improve the understanding of the electronic differences among the crystalline phases. The results will enable correlations between crystal structure and electronic properties, contributing to the fundamental understanding of the material and providing insights for optimizing its performance in solar energy conversion applications. (AU)