Edge Stability of BN sheets and Its Application for Designing Hybrid BNC Structures

TL;DR

This study uses first-principles calculations to analyze the edge stability and stresses of BN nanoribbons, revealing how their properties can guide the design of hybrid BNC structures with potential electronic and spintronic applications.

Contribution

It provides new insights into the edge energies, stresses, and electronic properties of BN nanoribbons, enabling the design of hybrid BNC structures with tailored functionalities.

Findings

Armchair BN nanoribbons are more stable than zigzag ones.

Edge stresses differ between armchair (compressive) and zigzag (tensile) BN nanoribbons.

Hybrid BNC structures can exhibit unique electronic and magnetic properties.

Abstract

First-principles investigations on the edge energies and edge stresses of single-layer hexagonal boron-nitride (BN) are presented. The armchair edges of BN nanoribbons (BNNRs) are more stable in energy than zigzag ones. Armchair BNNRs are under compressive edge stress while zigzag BNNRs are under tensile edge stress. The intrinsic spin-polarization and edge saturation play important roles in modulating the edge stability of BNNRs. The edge energy difference between BN and graphene could be used to guide the design of the specific hybrid BNC structures: in an armchair BNC nanoribbon (BNCNR), BN domains are expected to grow outside of C domains, while the opposite occurs in a zigzag BNCNR. More importantly, armchair BNCNRs can reproduce unique electronic properties of armchair graphene nanoribbons (GNRs), which are expected to be robust against edge functionalization or disorder. Within certain C/BN ratio, zigzag BNCNRs may exhibit intrinsic half-metallicity without any external constraints. These unexpected electronic properties of BNCNRs may offer unique opportunities to develop nanoscale electronics and spintronics beyond individual graphene and BN. Generally, these principles for designing BNC could be extended to other hybrid nanostructures.