Two-Dimensional Semiconducting Boron Monolayers

Abstract

The two-dimensional boron monolayers were reported to be metallic both in previous theoretical predictions and experimental observations. Unexpectedly, we have first found a family of boron monolayers with the novel semiconducting property as confirmed by the first-principles calculations with the quasi-particle GW approach. We demonstrate that the connected network of hexagonal vacancies dominates the gap opening for both the in-plane s+p and p orbitals, with which various semiconducting boron monolayers are designed to realize the band gap engineering for the potential applications in electronic devices. The semiconducting boron monolayers in our predictions are expected to be synthesized on the proper substrates, due to the similar stabilities to the ones observed experimentally.

Promising Thermoelectric Performance in Two-Dimensional Semiconducting Boron Monolayer

“…Figure 1B shows the Brillouin zone path, that is, Γ-Y-P 1 -Γ-N-P 1 . Based on Hu et al (Xu et al, 2017), the HSE06 band structure indicates that the β s 1 boron monolayer is an indirect semiconductor with a bandgap of 0.74 eV, and also, the phonon spectrum and molecular dynamics simulation confirm the thermal stability of this boron monolayer. In contrast to monolayer TMDCs with a large bandgap, the moderate bandgap of the boron monolayer may possess better electronic transport performance.…”

Semiconducting α′-boron sheet with high mobility and low all-boron contact resistance: a first-principles study

“…11,12 Derived from B 80 fullerene, 13 the triangular sheet with various hollow hexagons is more favorable for boron sheet, [14][15][16][17] resulting in various chemical and physical properties. Until now, most of 2D boron are concluded to be metallic, [14][15][16]18,19 whereas a few particular structures reveal semiconducting characteristic, 16,20 such as α′, 16 β 3 S , 20 antiferromagnetic borophenes (AFM-B), 21 and B 12-1 , 9 etc.…”

“…Furthermore, α′-boron is found to have high electron mobility (∼20 000 cm 2 V −1 s −1 ) because the conduction-band minimum (CBM) is dominated by a π bond, similar to graphene. Besides α′-boron, another semiconducting β 3 S -boron sheet predicted by Xu et al 20 with a triangle-lattice and higher energy is also considered as 2D FET channel, with relatively high carrier mobility as well. To choose appropriate contact electrodes which can form Ohmic contact with the above two semiconductors, in order to design the fully boron-sheet-based 2D FETs, the work functions of various metallic 2D boron phases are studied.…”

Low-temperature Liquid Exfoliation of Milligram-scale Single Crystalline Few-layer β12-Borophene Sheets as Efficient Electrocatalysts for Lithium–Sulfur Batteries

“…high-e cient adsorption, fast conversion of polysul des and long-term durability. As a typical 2D Dirac material consisted of the lightest solid element, 2D borophene with unique surface con guration and complex multicenter-two electron bonds has been earlier predicted as an ideal electrode material for Li-S batteries due to its native metallic conductivity 42 , large elastic modulus 43 , heavy anisotropy 44 , high Fermi velocity (6.6×10 5 m/s) 45 , excellent thermal and chemical stability 46 , large Li-ion surface mobility as well as strong bonding energy to polysul de clusters 47 . However, borophenebased Li-S cells have not yet been achieved for practical use so far owing to the absence of a facile route for the scalable production of 2D borophene nanomaterials.…”