Influence of doping Sn direction and concentration on vanadium pentoxide based on density functional theory

Abstract

Based on the first-principles calculation method of density functional theory, the influence of different directions and concentrations of Sn doping on V2O5 was discussed. The doping formation energy, electronic density of states, and isosurface charge density of different Sn doping directions and doping concentration structures are calculated. The calculation results of five different crystal orientation doping models show that the doped structure along the [111] crystal orientation has a smaller doping formation energy of 1.879 eV, which has the best electrical properties and the largest charge density. And the charge distribution is the most concentrated. It is most conducive to the formation of conductive filaments. In addition, as the doping concentration increases, the charge density gradually increases. When the doping concentration is 3.174%, the peak impurity energy level is the highest and the band gap is the smallest. At the same time, there is a tendency to form conductive filaments in the direction of charge extension [111], and the resistance change characteristics of vanadium pentoxide are best improved. The research results of this paper can provide certain theoretical guidance for improving the performance of resistive random access memory based on vanadium pentoxide.