Electronic, optical, and thermoelectric properties of Janus In-based monochalcogenides

Tuan V Vu; Vo T T Vi; Huynh V Phuc; Chuong V Nguyen; N A Poklonski; C A Duque; D P Rai; Bui D Hoi; Nguyen N Hieu

doi:10.1088/1361-648X/abf381

Electronic, optical, and thermoelectric properties of Janus In-based monochalcogenides

J Phys Condens Matter. 2021 May 4;33(22). doi: 10.1088/1361-648X/abf381.

Authors

Tuan V Vu^{1

2}, Vo T T Vi³, Huynh V Phuc⁴, Chuong V Nguyen⁵, N A Poklonski⁶, C A Duque⁷, D P Rai⁸, Bui D Hoi³, Nguyen N Hieu^{9

10}

Affiliations

¹ Division of Computational Physics, Institute for Computational Science, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
² Faculty of Electrical & Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
³ Department of Physics, University of Education, Hue University, Hue 530000, Vietnam.
⁴ Division of Theoretical Physics, Dong Thap University, Cao Lanh 870000, Vietnam.
⁵ Department of Materials Science and Engineering, Le Quy Don Technical University, Ha Noi 100000, Vietnam.
⁶ Department of Physics, Belarusian State University, Minsk 220030, Belarus.
⁷ Instituto de Física, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia.
⁸ Physical Sciences Research Center (PSRC), Department of Physics, Pachhunga University College, Mizoram University, Aizawl 796001, India.
⁹ Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.
¹⁰ Faculty of Natural Sciences, Duy Tan University, Da Nang 550000, Vietnam.

PMID: 33784649
DOI: 10.1088/1361-648X/abf381

Abstract

Inspired by the successfully experimental synthesis of Janus structures recently, we systematically study the electronic, optical, and electronic transport properties of Janus monolayers In₂XY(X/Y= S, Se, Te withX≠Y) in the presence of a biaxial strain and electric field using density functional theory. Monolayers In₂XYare dynamically and thermally stable at room temperature. At equilibrium, both In₂STe and In₂SeTe are direct semiconductors while In₂SSe exhibits an indirect semiconducting behavior. The strain significantly alters the electronic structure of In₂XYand their photocatalytic activity. Besides, the indirect-direct gap transitions can be found due to applied strain. The effect of the electric field on optical properties of In₂XYis negligible. Meanwhile, the optical absorbance intensity of the Janus In₂XYmonolayers is remarkably increased by compressive strain. Also, In₂XYmonolayers exhibit very low lattice thermal conductivities resulting in a high figure of meritZT, which makes them potential candidates for room-temperature thermoelectric materials.

Keywords: Janus group-III monochalcogenides; electronic structure; first-principles calculations; low-thermal conductivity; photocatalytic activity.