Conversion of Trivial Plumbene into Topological NTI as Quantum Material via Doping Strategy Using First Principle Quantum Chemical Calculations

Abstract

Science has shown a great deal of interest in the investigation of topological properties in twodimensional materials, especially Xenes. Investigations into 2D materials with several uses, including optoelectronics, sensors, and energy storage, are being stimulated by the demand for energy-efficient electronic gadgets. The objective of this study is to convert trivial insulator into topological non-trivial insulator using first principle quantum chemical calculations. In the current study, Si, Ge, Sn, C, and Cl atoms are used to study substitution doping in a Plumbene supercell. The full-potential linearized augmented plane wave (FP-LAPW) technique is used in computational research to assess structural, electrical and magnetic properties, while also considering future topological applications. Utilizing doping levels ranging from 11.1% to 50 %, revealing the distinctive topological characteristics that set the original and infused Plumbene supercells apart are observed. The hexagonal arrangement regulated by the P-3m1 space group is revealed by the examination of the Plumbene supercell's crystal structure. Pristine plumbene structure exhibits conventional insulating properties and has a large 3.0 eV band gap. Doped structures under GGA-PBE, on the other hand, showed semiconducting behavior with a direct band gap. Surprisingly, the supercell doped with 44.4% Cl exhibits conductor capabilities whereas the supercell doped with 50% doping exhibits topological insulator qualities. DOS calculations are consistent with these results as well. Pb atoms form strong covalent bonds with Si, Ge, Sn and Pb atoms, while Cl forms ionic bonds observed in electron density maps. Magnetic properties shows that neither doped nor pure structures exhibit ferromagnetic activity. It is interesting to note that structural deformation, a sign of the degree of doping, occurs at a doping level of 55.5%. Introduction of metals, metalloids and non-metals in Pristine plumbene supercell with different concentrations enhanced electrical and topological properties of plumbene. However, these claims require further experimental verification.