Semiconducting phase in borophene: role of defect and strain

Abstract

Boron is an interesting element due to its chemical and structural complexity. Recent synthesis of borophene led scientists to study boron monolayer based materials for various applications. Using density functional theory (DFT) calculations, nineteen different phases of boron monolayer (with hexagonal hole-densities from 1/32 to 8/32) are studied to understand their origin of buckling, stability and planarity. Projected densities of states of various phases of borophene based systems with defect are plotted into in-plane (s+px+py) and out-of-plane (pz) orbitals to understand the role of σ and π-bands towards their geometry and stability. Interestingly, λ5-sheet shows semiconducting properties under uniaxial/biaxial tensile/compressive strains and the λ5-sheet shows excellent dynamical, thermal and mechanical properties and thus a promising semiconducting phase for electronic devices.