Effect of heavy metal atom doping in black phosphorene from first-principles calculations

Abstract

First-principles density functional theory (DFT) calculations are powerful tools for investigating the properties of materials at the atomic and electronic scales. In this study, we use DFT to explore the geometric structures, electronic properties, and thermodynamic stabilities of substitutionally doped phosphorene sheets with elements from Groups IB and IIB of the periodic table. We find that the electronic properties of phosphorene are drastically modified by the d-orbital electrons of dopant atoms. With the exception of Ag- and Au-doped phosphorene, which retain semiconducting properties with reduced band gaps, doping with other heavy metal atoms (Cu, Zn, Cd, and Hg) induces distinct metallic characteristics. This semiconductor-to-metal transition primarily stems from the strong p-d orbital hybridization between dopants and the phosphorus atoms. Furthermore, the calculated formation energies of substitutionally doped phosphorene systems reveal that partially doped configurations can attain thermodynamic stability under suitable synthesis conditions. These results offer valuable guidance for designing novel 2D materials with tunable electronic and thermodynamic properties.