First-principles study of structural stability and electronic properties of polar MgAl2O4/Al interface

Abstract

In this study, first-principles computations were conducted to examine the interfacial structural stability and electronic characteristics of MgAl2O4(111)/Al (111). We investigated the surface properties of eight terminals of MgAl2O4(111) and showed that the surface models of the O2 (Mg) terminal, O2 (Al) terminal, O (Mg) terminal, O (Al) terminal, and Mg (Al) terminal are relatively stable. We constructed 15 MgAl2O4(111)/Al (111) interfacial models according to different interfacial stacking methods. By studying the interfacial binding properties, we found that the O2(Mg)/Al-HCP interface has the largest structural stability and binding strength among the MgAl2O4(111)/Al (111) interfaces. Investigation of the electronic properties of the interface showed that strong covalent and ionic bonds are formed between the O2(Mg)/Al and O2(Al)/Al interfaces, thereby confirming the electron transport between O and Al atoms at the interface.