Effect of tensile deformation on the optoelectronic properties of black phosphine-doped lithium atoms

Abstract

First-principle calculations of intrinsic and lithium-doped black phosphazene systems based on the CASTEP block of Materials Studio software were performed to study the structural stability and changes in the optoelectronic properties of the systems under different uniaxial tensile deformations, which showed that lithium doping caused the black phosphazene system to show metallicity from a direct bandgap semiconductor, and the structural stability of the doped system decreased with the increase of the tensile deformation. It is found that the band gap of intrinsic black phosphorine increases from 0.841 eV to 1.086 eV when the tensile deformation is increased from 0–4%, and decreases from 1.086 eV to 0.660 eV when the tensile deformation is continued to increase to 10%.From the analysis of the density of states, the density of states of all the systems is basically contributed by the s and p orbitals, and the contribution of the d orbitals is very small, with the contribution of the p orbitals dominating. The contribution of the p-orbitals is dominant. In terms of light absorption and reflection, the absorption peaks of the intrinsic black phosphorine strained system show a red-shifted, then blue-shifted and then red-shifted trend, and the reflection peaks show a red-shifted trend, while the absorption and reflection peaks of the lithium-doped black phosphorine strained system show a red-shifted trend.