The Electronic Properties and Friction Characteristics of GeSe/SnS Heterostructures Based on the DFT Theoretical Calculations

Constructing van der Waals (vdW) heterostructures offers a feasible approach for enhancing the electronic properties and obtaining superlubricity of various electromechanical devices. Here, the electronic and frictional properties of GeSe/SnS heterostructures were investigated through first-principle calculations based on density function theory. The GeSe/SnS bilayer with AC stacking configuration revealed a direct band structure with a gap value of about 0.95 eV and a standard typical type-II band alignment. Within the GeSe/SnS vdW heterostructure, AC stacking setup demonstrates a more uniform potential energy surface (PES) than AB stacking arrangement, verified by a lower friction barrier. The peak PES value of the GeSe/SnS heterostructure in AC stacking is merely 0.0016 eV. The weak vdW interaction between the adjacent layers in vdW heterostructure and smooth PES are responsible for reducing potential energy fluctuations and friction. The investigation on the friction characteristics of GeSe/SnS vdW heterostructure with AC stacking configuration provides valuable insights for understanding the atomic-scale friction behavior in two-dimensional (2D) materials.