Stabilization and Metallic to Semiconducting Transition in 2D Boron Sheet

Zhifen Luo

Xiaoli Fan Email

Yurong An 

Yan Hu

Fengxia Zhang

State Key Laboratory of Solidification Processing, Center for advanced lubrication and seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, 127 YouYi Western Road, Xi’an, Shaanxi 710072, China

Abstract

Bucked triangular,β12 and χ3 are the three lattices of atomic-thin boron sheet which have been realized experimental very recently. The three lattices all are metallic and dynamical unstable. By adopting the first-principles method based on the density functional theory, we predict the biaxial strain under which the β12 and χ3 boron sheets are stabilized. We also demonstrate the effectiveness of hydrogenation on stabilize the buckled triangular boron sheet. Additional, our calculations show that neither uniaxial nor biaxial strain stabilizes the buckled triangular boron sheet, and when the applied biaxial strain is larger than 14%, its anisotropic conductivity no longer exists. Moreover, the electronic band structures of the three boron sheets are controllable by modifying the hydrogen coverage. We find the Dirac cone in the fully hydrogenated buckled triangular boron sheet, and the metal-semiconducting transition in β12 and χ3 boron sheet caused by 100% and 50% hydrogenation. Our results reveal new electronic properties for the new class of 2D materials, borophene in the applications of electronics.

Stabilization and Metallic to Semiconducting Transition in 2D Boron Sheet