Effects of deformation on Zn atom-adsorbed borophene

Abstract

The effects of tensile and compressive deformation on the structural stability, electronic structure and optical properties of the Zn atom-adsorbed borophene system, which are exhibited by reflectivity, absorption coefficient, bandgap and adsorption energy, were studied using the first-principles calculations based on density functional theory (DFT). The borophene planes were found to be distorted following Zn atom adsorption. The adsorption energy calculations show that the stability decreases both under tensile and compressive strains. When tensile and compressive loading increase to 5%, respectively, the system loses the stability and the ability of adsorbing Zn atoms on borophene. The band structure and density of states analysis show that the band structure of borophene is changed by the Zn atom adsorption, with a band overlap near the Fermi level and more impurity energy levels in the conduction band. The hybridization is formed between Zn atom and borophene in the range of –12[Formula: see text]eV to 6[Formula: see text]eV, with the s and p orbitals both contributing to the conduction and valence bands, but p orbitals make a larger contribution to the total density of states than s orbitals. Studies of optical properties have shown that tensile and compressive strains both increase the dielectric constant of the adsorbed system, with compressive strains causing a redshift in the major peaks of the real and imaginary parts of the spectrum. The tensile strain has little effect on the absorption coefficient and reflectance of the borophene. As the compressive strain increases, the peak absorption coefficient of the adsorbed system is shifted to the blue and the peak reflectance is redshifted.