A First-Principles Study on the Adsorption of Small Molecules on Antimonene: Oxidation Tendency and Stability

TL;DR

This study uses first-principles calculations to explore how small molecules interact with antimonene, revealing its oxidation tendencies and stability, which are crucial for its potential applications in ambient conditions.

Contribution

It provides the first detailed analysis of molecule-antimonene interactions, highlighting oxidation risks and stability mechanisms distinct from phosphorene.

Findings

Oxygen molecules can easily split on antimonene, indicating oxidation susceptibility.

H2O acts as an acceptor, helping prevent further degradation of oxidized antimonene.

Oxygen has a stronger interaction with antimonene compared to phosphorene.

Abstract

Antimonene, a new group-VA 2D semiconducting material beyond phosphorene, was recently synthesized through various approaches and was shown to exhibit a good structural integrity in ambient conditions and various interesting properties. In this work, we perform systematical first-principles investigations on the interactions of antimonene with the small molecules CO, NO, NO2, H2O, O2, NH3 and H2. It is found that NO, NO2, H2O, O2, and NH3 serve as charge acceptors, while CO shows a negligible charge transfer. H2 acts as a charge donor to antimonene with the amount of charge transfer being ten times that of H2 on phosphorene. The interaction of the O2 molecule with antimonene is much stronger than that with phosphorene. Surprisingly, the kinetic barrier for the splitting of the O2 molecule on antimonene is low (~0.40 eV), suggesting that pristine antimonene may undergo oxidation in ambient conditions, especially at elevated temperatures. Fortunately, the acceptor role of H2O on antimonene, opposite to a donor role in phosphorene, helps to suppress further structural degradation of the oxidized antimonene by preventing the proton transfer between water molecules and oxygen species to form acids.