Electronic properties of two dimensional PtSSe/SrTiO3 Janus Van der Waals heterostructures

The structural stability and electronic properties of two dimensional PtSSe/SrTiO₃ Janus heterostructures were investigated using density functional theory calculations, considering both S and Se terminations into account. Ab-initio thermodynamics simulations revealed that the heterostructure formed with Se/Ti interface termination is more stable with an energy difference of 1.53 eV than the S/Ti termination. In contrast to the semiconducting nature of the free standing monolayers, electronic structure analysis revealed metallic behavior for the PtSSe/SrTiO₃ heterostructures. Possible charge transfer scenario is envisaged from SrTiO₃ to PtSSe, and type III (broken gap) band alignment is obtained for the heterostructure which is desirable for tunneling applications. The favorable energetic stability of these heterostructures indicate the possibility of realizing them in real-time experimental fabrication, and PtSSe/SrTiO₃ heterostructures can be promising for energy-efficient future-generation electronics.