Two-dimensional SiC/AlN based type-II van der Waals heterobilayer as a promising photocatalyst for overall water disassociation

Naim Ferdous; Md Sherajul Islam; Jeshurun Biney; Catherine Stampfl; Jeongwon Park

doi:10.1038/s41598-022-24663-y

Two-dimensional SiC/AlN based type-II van der Waals heterobilayer as a promising photocatalyst for overall water disassociation

Sci Rep. 2022 Nov 22;12(1):20106. doi: 10.1038/s41598-022-24663-y.

Authors

Naim Ferdous¹, Md Sherajul Islam^{2

3}, Jeshurun Biney¹, Catherine Stampfl⁴, Jeongwon Park^{1

5}

Affiliations

¹ Department of Electrical and Biomedical Engineering, University of Nevada, Reno, NV, 89557, USA.
² Department of Electrical and Biomedical Engineering, University of Nevada, Reno, NV, 89557, USA. sheraj_kuet@eee.kuet.ac.bd.
³ Department of Electrical and Electronic Engineering, Khulna University of Engineering and Technology, Khulna, 9203, Bangladesh. sheraj_kuet@eee.kuet.ac.bd.
⁴ School of Physics, The University of Sydney, Sydney, NSW, 2006, Australia.
⁵ School of Electrical Engineering and Computer Science, University of Ottawa, Ottawa, ON, K1N6N5, Canada.

Abstract

Two-dimensional (2D) van der Waals (vdW) heterostructures made by vertical assembling of two different layers have drawn immense attention in the photocatalytic water disassociation process. Herein, we suggest a novel 2D/2D vdW heterobilayer consisting of silicon carbide (SiC) and aluminum nitride (AlN) as an exciting photocatalyst for solar-to-hydrogen conversion reactions using first-principles calculations. Notably, the heterostructure presents an inherent type-II band orientation wherein the photogenic holes and electrons are spatially separated in the SiC layer and the AlN layer, respectively. Our results indicate that the SiC/AlN heterostructure occupies a suitable band-gap of 2.97 eV which straddles the kinetic overpotentials of the hydrogen production reaction and oxygen production reaction. Importantly, the built-in electric field at the interface created by substantial charge transfer prohibits carrier recombination and further improves the photocatalytic performance. The heterostructure has an ample absorption profile ranging from the ultraviolet to the near-infrared regime, while the intensity of the absorption reaches up to 2.16 × 10⁵ cm^-1. In addition, external strain modulates the optical absorption of the heterostructure effectively. This work provides an intriguing insight into the important features of the SiC/AlN heterostructure and renders useful information on the experimental design of a novel vdW heterostructure for solar energy-driven water disassociation with superior efficiency.