Etude des Propriétés Structurales, Électroniques et Optiques d’une monocouche du nitrure de bore hexagonal (hBN)

Abstract

II Abstract In this Master's thesis, the structural, electronic and optical properties of hexagonal boron nitride (hBN) in its two-dimensional (2D) form were calculated. For this, we used by simulation the VASP code which is based on the density function theory (DFT). The potential for exchange and correlation has been treated in the local density approximation (LDA), the generalized gradient approximation (GGA), and the generalized gradient approximation plus van der Waals interaction (GGA+ vdW). For the structural properties, the lattice parameter a of our two- dimensional structure has been theoretically calculated and shown to agree with the experimental parameter. The distances of the bonds of the monolayer and thê angles were also calculated. For the electronic properties, we calculated the band structures, the total density of states and the partial densities of states and on one showed in particular that our material is a direct wide gap semiconductor, contrary to its 3D structure. which presents an indirect band gap. Finally, we calculated the optical properties of our material, its absorbance, its reflectance and its transmittance for incident photons whose energy varies from 0 eV to 20 eV.