First-principles investigation on electronic properties and band alignment of group III monochalcogenides

Abstract

Using first-principles calculations, we investigated the electronic properties and band alignment of monolayered group III monochalcogenides. First, we calculated the structural and electronic properties of six group III monochalcogenides (GaS, GaSe, GaTe, InS, InSe, and InTe). We then investigated their band alignment and analysed the possibilities of forming type-I and type-II heterostructures by combining these compounds with recently developed two-dimensional (2D) semiconducting materials, as well as forming Schottky contacts by combining the compounds with 2D Dirac materials. We aim to provide solid theoretical support for the future application of group III monochalcogenides in nanoelectronics, photocatalysis, and photovoltaics.

Novel wide spectrum light absorber heterostructures based on hBN/In(Ga)Te

“…From our calculations, both InTe and GaTe monolayers have an indirect bandgap of E g = 1.38 eV and E g = 1.75 eV respectively, while hBN has a large direct bandgap of 4.63 eV. These results are in agreement with previous theoretical results obtained using the PBE functional [32,33,20,36]. As the PBE functional underestimates the band gap in semiconductors, hybrid functionals such is HSE must be used in order to obtain an accurate electronic properties.…”

“…Single layer group III monochalcogenides have been extensively researched recently [20,21,22,23]. As layered quasi 2D structures with weak interlayer binding forces, they are suitable for mechanical exfoliation to few layers or even monolayer.…”

Prediction of new phase 2DC2hgroup III monochalcogenides with direct bandgaps and highly anisotropic carrier mobilities

“…Structural prediction through artificial swarm intelligence computational structure searches on CALYPSO (Crystal structure AnaLYsis by Particle Swarm Optimization) 36 is applied systematically to the most discussed binary MXs in the III-VI family, namely InSe, InS, GaSe, and GaS. [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] Detailed information regarding this method can be found in the electronic supplementary information (ESI).…”

“…[1][2][3][4][5][6][7] In addition to the well-known graphene-like group IV semiconductors and group III-V binary compounds, [8][9][10] both experimental and theoretical investigations have expanded the 2D-semiconductor family by the discovery of monolayer group IV monochalcogenides, 11,12 transition metal dichalcogenides, 13,14 black phosphorus, 15,16 and group III monochalcogenides. [17][18][19][20][21][22] Nevertheless, the zero band gap in graphene, 11 low electron mobility in transition metal dichalcogenides, 13 and the structural instability of black phosphorus under moisture conditions greatly restrict their applications. 16 Therefore, novel 2D semiconductors with sizable band gaps, high carrier mobilities, and strong stability are in great request.…”

Fundamental Properties of Hydrogen-Functionalized GaSe Monolayer

“…On the other hand, with the development of graphene and graphene-based materials, − the metal chalcogenides group has gained rapidly growing interest. ,− The metal monochalcogenides labeled MX (M: metal; X: chalcogen atoms) − are one class of this group that has been synthesized and analyzed in both experimental and theoretical studies. ,,− As a typical member of the MX group, GaSe is an emergent candidate due to its excellent performance in nonlinear optics and the generation of electromagnetic waves. To enhance its optical properties, various elements including S, Te, Ag, and Al have been doped on GaSe crystal − suggesting the further optimum growth technique.…”