Properties and electronic structure of Al/Mo2C interfaces: insights from first principle simulation

Good interface bonding is the basic prerequisite to achieve a high thermal conductivity of the composites. Clarifying the binding mechanism of Al/Mo2C interface is of great significance for the scheme design of Al/Diamond interface regulated by Mo element. The atomic structure and electronic properties of Al(111)/Mo2C(0001) interfaces and the influence of Mo doping on its adhesion work were studied by using the first principles method based on density functional theory. Eight interface configurations consisting of four possible stacking sites and two types of structures are considered. The consistency between our results and the previous experimental and theoretical results indicates that the calculation method and setting selection are indicated to study the interfaces present in this work. Adhesion work and interface energy analysis show that the bonding strength and interface stability of the Mo-termination interface are better than those of the C-termination interface, among which the Mo-fcc-Al interface is the best and the C-hcp-Al interface is the worst. The study of the electronic structure shows that the interaction between interface atoms forms a bond with metallic characteristics and Mo doping into Al matrix will weaken the bonding of Al/Mo2C interface.