Mechanical and Chemical Stability of Monolayer Black Phosphorous Studied by Density Functional Theory Simulations

• Published in: Journal of physical chemistry. C 2018-10, Vol.122 (39), p.22366-22373
• Main Authors: Eslamibidgoli, Mohammad Javad, Eikerling, Michael H
• Format: Article
• Language: English
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.8b04344

Simulations based on electronic density functional theory have been employed to study the  stability of phosphorene under mechanical stress as well as oxidative conditions. To understand the mechanical response, biaxial strain was applied along zigzag and armchair directions, and the potential energy surface was generated. Poisson’s ratio and Young’s modulus were calculated along each direction revealing the anisotropic response of the material. Under large strain conditions, several stable or metastable phases were identified including transformation from black phosphorus to white phosphorus and polymeric phases. To evaluate the chemical stability, surface mixing energies of phosphorene oxide were calculated as a function of oxygen coverage. Results indicate the formation of PO3 and PO4 chains at oxygen coverage above 0.5 monolayers, suggesting a multistep oxidation process that leads ultimately to the formation of P2O5. Ab initio molecular dynamics simulations with an additional water molecule revealed the hydrophobic nature of pristine black phosphorus in comparison to the hydrophilic nature of oxidized black phosphorus.