Structural, electronic and polarization properties of 2D Janus MXY (M = Hf; X = S, Se; Y = Te) monolayers
In this work, the structural, electronic and polarization properties of 2D Janus MXY (M = Hf; X = S, Se; Y = Te) monolayers were calculated and analyzed via density functional theory calculations. Results indicate that both 2D HfSTe and HfSeTe possess metallic band structures, and that their structural parameters are close in values implying that a difference in the X atom configuration does not significantly impact the lattice constant. It is found that charge distribution asymmetry due to different atomic layer configurations resulted to a net dipole moment perpendicular to the surface, which is very sensitive to changes in the net charge transfer to the X and Y atoms. Such observation could be tapped in the design of 2D Janus monolayers with the desired controllability of properties that can be influenced by polarization.