Investigation of the Stability and Electronic Structures for Exohedral Aln Doped (Mono and Double)-Layer MgO Nanosheet s: A DFT Approach

Nibras Mossa Umran

doi:10.17762/pae.v58i1.1351

Abstract

In present work, a detailed analysis of density functional theory (DFT) study performed on pure and doped MgO nanosheet(MgONs). The aim of this work is to explore the stability skeleton, and electronic properties of mono layer of the MgO nanosheets and analogous double-layers with various positions of exohedral Aln dopant atoms. Our results for pure and doped MgO nanosheet corroborate with previous theoretical and experimental data. Optimized structures of monolayer and analogous double-layers of MgO nanosheet (MgONs) result in stable 2-D configuration, especially on doping with large concentrations. It has been observed that the band gap decreases with the increase in concentration of doping while the electronegativity increases.

Highlights

Nanomaterials have attracted a great interest for theoretical and experimental research due to their unique physical and chemical characteristics which depend on the shape and size of nanomaterials, like hardness with high conductivit, [1, 2]
The 2D-MgO with both polar (111) and nonpolar (001) orientations have been successfully grown on various substrates experimentally [3,4,5,6,7,8,9,10]. This leads to the possibility of changing the electronic structure through doping which has recognized as a favorable alleyway to tune the properties of oxide materials toward the demands of different physics and chemistry applications
Further on comparing the binding energies of both structures, it was found that, the binding energy of the optimized MgO nanosheet (MgONs)(111) system decreases by about 0.28 eV per Mg−O pair, which indicates that this MgONs(111) is more stable than the MgONs(100)

Summary

Introduction

Nanomaterials have attracted a great interest for theoretical and experimental research due to their unique physical and chemical characteristics which depend on the shape and size of nanomaterials, like hardness with high conductivit, [1, 2]. The 2D-MgO with both polar (111) and nonpolar (001) orientations have been successfully grown on various substrates experimentally [3,4,5,6,7,8,9,10] This leads to the possibility of changing the electronic structure through doping which has recognized as a favorable alleyway to tune the properties of oxide materials toward the demands of different physics and chemistry applications. Density functional theory (DFT) study for electronic calculations of MgO mono-layer have shown to display a more fascinating feature than its bulk phase for instance shrinking the band gap from 7.8 eV to 3.1 eV (for GGA) and 4.2 eV (for GGA-mBJ) [12]. Three geometries i.e mono layer of MgO NSs in first and second case, and two layers of MgONs in the third case have been considered for investigation

Objectives

Results

Conclusion