Estudo das propriedades energéticas, estruturais e eletrônicas da adsorção de Au em siliceno com defeitos estruturais

Abstract

Recent advances in experimental [1] techniques have produced interesting new two-dimensional materials. One of the most promising materials for chemical and physical applications is graphene, which has been widely studied. Silicene, a counterpart of graphene, also has attracted the attention of many researchers due to their fundamental physical properties (such as being a topological insulator) and due to its easy integration to current silicon-based technology. Defects in silicene can change their physical properties. Theoretical studies indicate that the silicene with [2] Stone-Wales defects becomes semiconductor [3]. Another type of defect that may occur in silicene are grain boundaries defects that are present in graphene and silicon. The adsorption of atoms in silicene can change its electronic properties, for example, metallic, semi-metallic or semiconducting systems can be observed, depending on the type of adsorbed [4] atoms. In this dissertation we propose to investigate via computational simulation the effects of adsorption of gold on the structural and electronic properties of silicene with Stone-Wales defects and grain [5] boundaries. Our calculations were performed using Density Functional Theory, as implemented in the Openmx code. We also investigated the effect of the spin-orbit [6] interaction on these systems. Our results indicate that the gold atom prefers occupy the defect [7] region indicating a possible formation of lines or clusters of gold atoms along the defective regions. We also observe metallic or semiconducting structures depending on the adsorption site of the gold atom.