First-principles screening upon Janus PtXY (X, Y = S, Se and Te) monolayer under applied biaxial strains and electric fields

In this paper, we using the first-principles theory systemically investigate the geometric and electronic properties of the PtXY (X, Y = S, Se and Te) monolayers under the applied biaxial strains and electric fields. The optimized morphologies, deformation charge density, band structure and orbital DOS are plotted and analyzed. Our findings indicate that the applied biaxial strains can largely impact the morphologies of the PtXY systems while the electric fields do not. Given the remarkable charge-transfer crossing the X and Y planes caused by applied biaxial strains and electric field, the electronic property as well as the bandgap of the PtXY systems are modulated largely. It is conclude that PtSSe monolayer is a proper tensile sensing material while the PtSTe and PtSeTe monolayers are potential compressive sensing candidate. Meanwhile, PtSSe and PtSTe systems have desirable linear sensitivity to the applied electric field in terms of electrical conductivity, while the PtSeTe monolayer is only linearly sensitive for the negative electric field. The I-V analysis reveals the resistance property of the PtXY monolayers under various voltages and is consistent with the BS analysis. Our work uncover the physicochemical properties of the PtXY monolayer for typical applications and give the guidance to unfold a new orientation to explore novel semiconductor devices.