Two‐dimensional Janus group‐III ternary chalcogenide monolayer compounds B₂XY, Al₂XY, and BAlX₂ (X, Y = S, Se, Te) with high carrier mobilities

Abstract

First-principles approach based on density functional theory is employed in order to investigate the structural, electronic, and mechanical properties of the two-dimensional Janus group-III ternary chalcogenide monolayer (G3TCM) semiconductor series, B 2 XY, Al 2 XY, and BAlX 2 (X, Y = S, Se, Te; X ≠ Y). The effective masses, band gaps, and carrier mobilities of the entire series of Janus G3TCM compounds are evaluated to comprehensively examine their feasibility as an ingredient in nanoscale electronic device. All the G3TCM compounds proposed in this study are suggested to be realizable based on phonon calculations and estimated mechanical stability. The indirect bandgap of B 2 XY and Al 2 XY can be switched to direct bandgap in BAlX 2 by constructing Janus-type structure using group-III elements. The computationally obtained carrier mobilities according to the deformation potential theory indicated that B 2 SSe and BAlSe 2 have exceptional electron and hole carrier mobility of 2.02 Â 10 4 and 2.58 Â 10 5 cm 2 V À1 s À1 , respectively, at room temperature.

A theoretical study of novel orthorhombic group-IVB nitride halide monolayers for photocatalytic overall water splitting

“…For all monolayers, the carrier mobility can be up to 10 3 cm 2 V −1 s −1 , which is higher than those of PdTe 2 46 and Al 2 STe. 47 It indicates that all monolayers have the fast transport capability. Interestingly, the mobilities along the x direction are all higher than those along the y direction.…”

Ferro-piezoelectricity in emerging Janus monolayer BMX2 (M = Ga, In and X = S, Se): ab initio investigations

“…The Young's modulus ranges from 93.87 N m −1 (BInSe 2 ) to 118.80 N m −1 (BGaS 2 ), which are greater than those reported for BAlX 2 (X = S, Se, Te) chalcogenide compounds. 40 The gallium containing compounds have a greater Young's modulus than the indium containing ones. The dimensionless Poisson's ratio ( ν ) is an important metric in industrial production since it provides more direct information concerning adhesion strength than any other elastic constant.…”

Synergistic Effect of Fluorination and Molecular Orientational Order on the Dielectric Properties of Low-κ Liquid Crystal Polymer Films

“…All density functional theory (DFT) calculations were performed using a plane-wave basis Vienna ab initio simulation package (VASP) code. , The exchange–correlation potential was calculated by the Perdew–Burke–Ernzerhof functional. , The DFT-D3 van der Waals correction method proposed by Grimme, including the zero-damping function, was applied to include the dispersion force . Valence electron wave functions were expanded in a plane wave basis up to an energy cutoff of 400 eV.…”