Effects of adatoms and physisorbed molecules on the physical properties of antimonene

Abstract

A recent study predicted that a 2D single layer of antimony in buckled honeycomb as well as asymmetric washboard structures, named antimonene, is stable at high temperature and displays semiconducting properties. Based on first-principles, spin-polarized density functional calculations, we investigated chemisorption of selected adatoms and physisorption of molecules on two antimonene phases. Since adspecies-adspecies interaction is minimized by using large supercells, our results mimic the effects of isolated, single adatoms or molecules. We found that molecules such as H 2 , O 2 , and H 2 O neither form strong chemical bonds nor dissociate; they are physisorbed with a weak binding energy without affecting the properties of antimonene. The adatoms, such as H, Li, B, C, N, O, Al, In, Si, P, Cl, Ti, As, and Sb, are chemisorbed with significant binding energy, whereby the atomic and electronic structures are modified locally. Boron and carbon adatoms are implemented into buckled antimonene crystal leading to a local reconstruction of the crystal. Nitrogen gives rise to Stone-Wales type defects. The localized states originating from adatoms give rise to diversity of electronic structure. The lowest conduction and highest valence bands of antimonene in asymmetric washboard structures have very high curvature. Once combined with adatom states, these bands offer a variety of features. Specific adatoms lead to spin polarization, attain magnetic moments, and can attribute a half-metallic character to antimonene.

Two-dimensional pnictogens: A review of recent progresses and future research directions

“…Some adatoms give rise to spin polarization and attain magnetic moments. 233 The results show that the atmospheric gas molecules (N 2 , CO 2 , O 2 , and H 2 ) are weakly bound to antimonene, while the polluted gas adsorbates (NH 3 , SO 2 , NO, and NO 2 ) show relatively strong affinity toward antimonene with considerable adsorption energies and significant charge transfers. 234 Also, NO, NO 2 , H 2 O, O 2 , and NH 3 molecules act as a acceptor in antimonene, whereas H 2 behaves as a donor.…”

Strain engineering of antimonene by a first-principles study: Mechanical and electronic properties

“…25 This is in stark contrast to the poor stability of its predecessor -phosphorene. While great strides have been made towards understanding the optical characteristics, 33 doping possibilities, [34][35][36] functionalization-induced charge dynamics, 37,38 many-body physics 39 and quantum-confinement effects 40 of antimonene, there remain lots of mystery surrounding this new 2D material, especially with regard to its response to applied strains, temperature loads 3 and external electric fields.…”

A promising two-dimensional channel material: monolayer antimonide phosphorus

“…Thus, tuning the carrier mobility of phosphorene is feasible through general alloying strategy experimentally. Given the biotoxicity of As1−xPx (due to the presence of As) and the theoretical prediction that monolayer antimonene probably has a higher air stability than phosphorene and α-As1−xPx [33], we employ the Sb element to modulate the electronic properties of α-phosphorene.…”