Point Defects in Two-Dimensional γ-Phosphorus Carbide

Defects are inevitably present in two-dimensional (2D) materials and usually govern their various properties. Here, a comprehensive density functional theory-based investigation of seven kinds of point defects in a recently produced gamma allotrope of 2D phosphorus carbide (gamma-PC) is conducted. The defects, such as antisites, single C or P, and double C and P and C and C vacancies, are found to be stable in gamma-PC, while the Stone-Wales defect is not presented in gamma-PC due to its transition-metal dichalcogenides-like structure. The formation energies, stability, and surface density of the considered defect species as well as their influence on the electronic structure of gamma-PC is systematically identified. The formation of point defects in gamma-PC is found to be less energetically favorable than in graphene, phosphorene, and MoS2. Meanwhile, defects can significantly modulate the electronic structure of gamma-PC by inducing hole/electron doping. The predicted scanning tunneling microscopy images suggest that most of the point defects are easy to distinguish from each other and that they can be easily recognized in experiments.

Automated summary

This study investigated seven kinds of point defects in a two-dimensional phosphorus carbide gamma allotrope, finding that these defects have a significant impact on the electronic structure of the material, with slightly higher formation energies compared to other materials.