# Two-dimensional boron on Pb (110) surface

## TL;DR

This study uses ab initio simulations to explore the formation and stability of 2D boron structures on Pb(110), revealing stable Dirac materials with notable mechanical properties.

## Contribution

It demonstrates the potential to form stable 2D boron structures with Dirac cones on Pb(110) surfaces, including a new graphene-like boron phase with high mechanical anisotropy.

## Key findings

- Discovery of stable Pmmn boron with Dirac cones
- Identification of a more stable P2_1/c boron structure
- Young's modulus comparable to graphene

## Abstract

We simulate boron on Pb(110) surface by using ab initio evolutionary methodology. Interestingly, the two-dimensional (2D) Dirac Pmmn boron can be formed because of good lattice matching. Unexpectedly, by increasing the thickness of 2D boron, a three-bonded graphene-like structure (P2_1/c boron) was revealed to possess double anisotropic Dirac cones. It is 20 meV/atom lower in energy than the Pmmn structure, indicating the most stable 2D boron with particular Dirac cones. The puckered structure of P2_1/c boron results in the peculiar Dirac cones, as well as substantial mechanical anisotropy. The calculated Young's modulus is 320 GPa.nm along zigzag direction, which is comparable with graphene.