Optoelectronic and photocatalytic behaviour of a type-II GaAlS2/HfS2 heterostructure: Ab initio study

Disha Mehta; Yashasvi Naik; Nidhi Modi; P R Parmar; Pankajsinh B Thakor

doi:10.1088/1361-6528/ad43f3

Optoelectronic and photocatalytic behaviour of a type-II GaAlS2/HfS2 heterostructure: Ab initio study

Nanotechnology. 2024 Apr 26. doi: 10.1088/1361-6528/ad43f3. Online ahead of print.

Authors

Disha Mehta¹, Yashasvi Naik¹, Nidhi Modi², P R Parmar¹, Pankajsinh B Thakor³

Affiliations

¹ Department of Physics, Veer Narmad South Gujarat University Department of Physics, Udhna magdalla road, surat, Surat, Gujarat, 395007, INDIA.
² Department of Physics, Sir P.T. Sarvajanik Collage of Science, Surat 395001, Gujarat, India, Athawalines, Surat, 395001, INDIA.
³ Department of Physics, Veer Narmad South Gujarat University Department of Physics, Surat, Gujarat 395007, Surat, Gujarat, 395007, INDIA.

PMID: 38670075
DOI: 10.1088/1361-6528/ad43f3

Abstract

Theoretical examination based on first principle computation has been conducted for van der Waals heterostructure (vdwHS) GaAlS2/HfS2 including structural, optoelectronic and photocatalytic characteristics. From the adhesion energy calculation, the AB configuration of GaAlS2/HfS2 vdwHS is the most stable. A type-II GaAlS2/HfS2 vdwHS is a dynamically and thermally stable structure. The band edge position, projected band, and projected charge densities verify the type-II alignment of GaAlS2/HfS2 vdwHS. For GaAlS2/HfS2, GaAlS2 is acting as a donor and HfS2 is acting as an acceptor ensured by the charge density difference plot. The electron localized function validates the weak van der Waals interaction between GaAlS2 and HfS2. The GaAlS2/HfS2 vdwHS possess an indirect bandgap of 1.54 eV with notable absorption in the visible range. The findings assure that the GaAlS2/HfS2 vdwHS is an efficient photocatalyst for pH 4 to 8. The band alignment of GaAlS2/HfS2 is suitable for z-scheme charge transfer. The strain influenced band edge suggests that the GaAlS2/HfS2 vdwHS remains photocatalytic for strain -4% to +6% in both cases of uniaxial and biaxial strains.&#xD.

Keywords: GaAlS2/HfS2 heterostructure; Optoelectronic behaviour; Photocatalytic activity; Strain effect; Type-II band alignment; Z-scheme.