Jump to main content
Jump to site search


Effects of native defects and Cerium impurity on monoclinic BiVO4 photocatalyst by PBE+U calculations

Abstract

In this article, we report periodic density functional theory (DFT) investigation on the formation of the native defects and Cerium doping in monoclinic BiVO4 (m-BiVO4) and their effect on the electronic structures, using the Perdew-Burke-Ernzerhof functionals corrected for on-site Coulombic interactions (PBE + U). From the point defect formation energies and transition levels, the Bivac (Bi vacancy), Vvac (V vacancy), Oint (O interstitial) and CeV (Ce doping on V site) defects in m-BiVO4 are identified as shallow acceptors. For Ce doping in m-BiVO4, substitution of Bi by Ce is energetically favorable in the single positively charged state (Ce_Bi_1+ ) under Bi/V-poor conditions, while substitution of V by Ce is in the single negatively charged state (Ce_V_1- ) under O-rich conditions. The calculated electronic structures suggest that Ce_Bi_1+ degrades the activity by an unoccupied deep level in the gap region, mainly composed of Ce 4f orbitals, which makes this defect as the photogenerated electron-hole recombination center, in good agreement with experimental results. For Ce_V_1- , no localized state exists within the calculated band gap. Its formation energy is all sensitive to the chemical potentials and Fermi energy, suggesting that the Bi/V-poor and O-rich conditions are desirable to eliminate the deep-level states and to improve photocatalysis. Our results provide insights into how to enhance the photocatalytic activity of m-BiVO4 for energy and environmental applications through rational design of defect controlled synthesis conditions.

Back to tab navigation

Supplementary files

Article information


Submitted
12 Apr 2020
Accepted
12 Oct 2020
First published
12 Oct 2020

Phys. Chem. Chem. Phys., 2020, Accepted Manuscript
Article type
Paper

Effects of native defects and Cerium impurity on monoclinic BiVO4 photocatalyst by PBE+U calculations

J. Zhang, X. Chen, M. Deng, H. Shen, H. Li and J. Ding, Phys. Chem. Chem. Phys., 2020, Accepted Manuscript , DOI: 10.1039/D0CP01983F

Social activity

Search articles by author

Spotlight

Advertisements