Tuning the optoelectronic properties of PtS2/PtSe2 heterostructure via strain engineering

• Published in: Journal of computational electronics 2024-12, Vol.23 (6), p.1413-1422
• Main Authors: Zhao, Yanshen, Yang, Lu, Liu, Huaidong, Sun, Shihang, Wei, Xingbin
• Format: Article
• Language: English
• Subjects: Compressive properties; Conduction bands; Density functional theory; Electric fields; Electrical Engineering; Electromagnetic absorption; Electrons; Energy; Energy gap; Engineering; First principles; Free energy; Graphene; Heat of formation; Heterostructures; Light reflection; Mathematical and Computational Engineering; Mathematical and Computational Physics; Mechanical Engineering; Optical and Electronic Materials; Optical reflection; Optoelectronics; Photocatalysis; Photoelectric effect; Photoelectricity; Tensile strain; Theoretical; Ultraviolet reflection
• ISSN: 1569-8025; 1572-8137
• DOI: 10.1007/s10825-024-02219-9

In this paper, based on the first-principles calculation method of density functional theory, the PtS 2 /PtSe 2 heterostructure with the lowest formation energy is selected from five different stacking modes. At the same time, the phonon spectrum of PtS 2 /PtSe 2 heterostructure has no imaginary frequency, so the structure is stable. After that, the changes of photoelectric properties of heterostructures under tensile and compressive strains were studied. It is concluded that the PtS 2 /PtSe 2 heterostructure is a semiconductor with indirect band gap and type II band arrangement. With the increase of tensile strain, the band gap value decreases from 0.927 to 0.565 eV, and the minimum value of the conduction band is transferred from the high symmetry point M point to the K point by 8% biaxial tensile strain. The biaxial tensile strain can effectively improve the dielectric constant of the PtS 2 /PtSe 2 heterostructure. When the strain reaches 8%, the dielectric constant is nearly twice as high as the intrinsic value and reaches 11.6, which improves the charge retention ability. The light absorption of PtS 2 /PtSe 2 heterostructure reaches 13.7 × 10 4  cm −1 under compressive strain, and the stability of light absorption is enhanced. The optical reflection ability of PtS 2 /PtSe 2 heterostructure is significantly enhanced under tensile strain, indicating that the biaxial strain has a regulatory effect on the absorption and reflection ability of light. The valley values of all systems near the ultraviolet region show a linear increase trend, which changes the transmittance of the heterostructure. These findings broaden the application of PtS 2 /PtSe 2 heterostructures in optoelectronic engineering.