Issue 19, 2022

Exploring the effect of partial B-site Al3+–Mg2+ dual substitution on optoelectronic, surface, and photocatalytic properties of BaTaO2N

Abstract

BaTaO2N is appraised to be one of the few promising 600 nm-class photocatalysts for solar water splitting. However, the presence of structural defects and low charge separation limits its photocatalytic activity. Compared with mono substitution, dual substitution can be more effective in engineering the structural defects and improving the photocatalytic activity if foreign ions are suitably selected. In this work, we involve a dual-substitution approach to partially substitute Al3+ and/or Mg2+ for Ta5+ in BaTaO2N. By maintaining the maximum concentration of Al3+–Mg2+ dual substitution at 5%, the effect of the Al3+–Mg2+ cosubstituent ratio on the optoelectronic, surface, and photocatalytic properties of BaTaO2N is investigated. The Al3+–Mg2+ dual substitution leads to the shift of optical absorption edge toward shorter wavelengths, increasing the optical bandgap energy of BaTaO2N. This effect is more pronounced in the samples with a higher concentration of Mg2+ due to the replacement of N3− by a large number of O2− to compensate charge balance. The initial reaction rates for the evolution of O2 and H2 reveal the improvement in the photocatalytic activity of BaTaO2N due to the partial Al3+–Mg2+ dual substitution. Higher O2 evolution is observed in the samples with a higher concentration of Mg2+, while the H2 evolution rate significantly relies on the increased concentration of Al3+. According to the density functional theory (DFT) calculations, the effective masses of electrons become slightly lower than that of pristine BaTaO2N after partial Al3+–Mg2+ (co)substitution, while a contrary tendency is observed for the effective masses of holes. The calculated positions of the valence band maximum and conduction band minimum are aligned with respect to the normal hydrogen electrode (NHE), and partial Al3+–Mg2+ (co)substituted BaTaO2N photocatalysts can be promising candidates for visible-light-induced water splitting.

Graphical abstract: Exploring the effect of partial B-site Al3+–Mg2+ dual substitution on optoelectronic, surface, and photocatalytic properties of BaTaO2N

Supplementary files

Article information

Article type
Paper
Submitted
30 5 2022
Accepted
03 8 2022
First published
03 8 2022
This article is Open Access
Creative Commons BY-NC license

Mater. Adv., 2022,3, 7348-7359

Exploring the effect of partial B-site Al3+–Mg2+ dual substitution on optoelectronic, surface, and photocatalytic properties of BaTaO2N

M. Hojamberdiev, R. Vargas, Z. C. Kadirova, K. Teshima and M. Lerch, Mater. Adv., 2022, 3, 7348 DOI: 10.1039/D2MA00611A

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements