High-Throughput First-Principles Design of van der Waals Stabilized Two-Dimensional Metals in Hexagonal Boron Nitride Sandwich Heterostructures.

Two-dimensional (2D) metals offer unique opportunities for exploring extreme electronic confinement and developing next-generation devices, yet their freestanding forms are often thermodynamically unstable. Here, we systematically explore a van der Waals (vdW) encapsulation strategy using hexagonal boron nitride (h-BN) to stabilize 2D metallic layers, constructing [h-BN]x/My/[h-BN]x sandwich heterostructures via high-throughput first-principles calculations. Starting from 34 bulk nonmagnetic metals, over 700 monolayer candidates were generated, narrowed to 107 after symmetry filtering. Lattice-matching produced 60 representative heterostructures, with 49 successfully converged upon structural optimization. Several (e.g., Cu and Au) showed thermodynamic stability confirmed by phonon dispersion and ab initio molecular dynamics (AIMD), along with excellent transport properties. This work establishes a compact computational database of vdW-stabilized 2D metals and theoretical guidance for designing ultrathin, high-conductivity materials for nanoelectronics.