Borophene: A novel boron sheet with a hexagonal vacancy offering high sensitivity for hydrogen cyanide detection

Abstract

Elemental boron is electron-deficient and cannot form graphene-like structures. Instead, triangular boron lattices with hexagonal vacancies have been predicted to be stable. Recently, experimental and theoretical studies showed that the B36 sheet has a planar C6V structure with a central hexagonal hole, providing the first experimental evidence for the viability of atom-thin boron sheets with hexagonal vacancies, dubbed borophene. Herein, the sensitivity of the B36 borophene toward HCN molecule is theoretically investigated. The electronic properties of HCN/borophene adducts are strongly dependent on the molecular adsorption configuration. Owing to strong interactions between HCN and the B36 borophene, dramatic changes in the electronic properties of the sheet together with large HOMO-LUMO gap variations were observed. We found that the adsorption of HCN molecule can significantly influence the electronic structure of B36 borophene. Our results demonstrate that the B36 nanosheet is sensitive to the concentration (or pressure) of HCN gas. Our predictions can serve a guideline for further theoretical and experimental researches in investigating the electronic properties of the B36 borophene nanosheet.