Semiconducting Group 15 Monolayers: A Broad Range of Band Gaps and High Carrier Mobilities

Abstract

Optoelectronic applications require materials both responsive to objective photons and able to transfer carriers,so new two-dimensional (2D) semiconductors with appropriate band gaps and high mobilities are highly desired. Ab road range of band gaps and high mobilities of a2Dsemiconductor family,c omposed of monolayer of Group 15 elements (phosphorene,arsenene,antimonene,bismuthene) is presented. The calculated binding energies and phonon band dispersions of 2D Group 15 allotropes exhibit thermodynamic stability.T he energy band gaps of 2D semiconducting Group 15 monolayers cover awide range from 0.36 to 2.62 eV,which are crucial for broadband photoresponse.S ignificantly,p hosphorene,a rsenene,a nd bismuthene possess carrier mobilities as high as several thousand cm 2 V À1 s À1 .Combining such broad band gaps and superior carrier mobilities,2 DG roup 15 monolayers are promising candidates for nanoelectronics and optoelectronics.

Few‐layer Bismuthene: Sonochemical Exfoliation, Nonlinear Optics and Applications for Ultrafast Photonics with Enhanced Stability

“…[56] In our work, the Tauc plot of the spectrum indicates a fitted optical band gap of 1.028 eV for bismuthene in Figure 5 (b), which is slightly larger than the theoretically calculated energy band gaps of bismuthene. [18] In addition, the absorption peak at 0.795 eV corresponds with a 1559.18 nm wavelength in our experiments, which strongly suggests that few-layer bismuthene is indeed a promising optical material for the telecommunication band.…”

“…Recently, high stability of β-phase bismuthene has been theoretically predicted. [18] However, direct experimental evidence on the stability of β-phase bismuthene remains unexplored. Consequently, the stability of β-phase bismuthene in air must be verified.…”

Two-dimensional antimonene single crystals grown by van der Waals epitaxy

“…Monolayer β-phase antimonene consists of buckled hexagonal rings composed of Sb atoms connected through sp 3 bonding. Moreover, bulk antimony can be viewed as the ABC stacking of monolayer anitmonene10111314. Another common allotrope of antimony has the orthorhombic structure (α-phase), similar to that of black phosphorus displayed in Supplementary Fig.…”

“…In contrast to BP, another group-VA element composed 2D material, antimonene, was recently predicted to be of good stability, as well as extraordinary properties through first-principle calculations10111213. Zhang et al 10 further predicted that among several possible allotropes of monolayer antimonene, the rhombohedral phase, ususally viewed as ABC stacking of monolayer antimonene (β-phase), has the best stability.…”

“…They also predicted that the band structures of antimony would transfer from semimetal in the bulk form into semiconductor when thinned to one atomic layer. According to theoretical calculations, anitmonene presents high carrier mobility11, superior thermal conductivity14, strain induced band transition1015 and promising spintronic properties16. Despite the rapid progress of theoretical works about anitmonene mentioned above, reports of experimental studies on antimonene is still scarce171819.…”