Abstract
This study presents a first-principles investigation of \(\hbox {SiO}_2\) / \(\hbox {MoS}_2\) and \(\hbox {SiO}_2\) / \(\hbox {WS}_2\) interfaces, examining how surface terminations, van der Waals (vdW) corrections, and functional choices impact structural stability and electronic properties. Using density functional theory with generalized gradient approximation (GGA; PBE, PBEsol, revPBE), meta-GGA (SCAN, \(\hbox {r}^2\) SCAN), and hybrid (PBE0) functionals, we assess the effect of vdW correction schemes (D2, D3, Tkatchenko-Scheffler) on interfacial energetics and separation. The results show that vdW corrections are essential for accurate GGA descriptions, while meta-GGAs yield similar accuracy even without them, enabling efficient modeling of \(\hbox {SiO}_2\) /2D heterostructures. Additionally, \(\hbox {SiO}_2\) surface morphology plays a significant role, with fully saturated interfaces showing lower energy and greater interlayer separations. In both \(\hbox {SiO}_2\) / \(\hbox {MoS}_2\) and \(\hbox {SiO}_2\) / \(\hbox {WS}_2\) systems, band gap predictions using PBE0 closely match the experimental values, underscoring the value of hybrid functionals for accurate electronic structure calculations.
Graphic Abstract
