Enhanced Mg/graphene interface adhesion using intermediate MgO layers: First-principles prediction and analysis

Graphene-reinforced Mg matrix composites suffer seriously from the weak Mg/graphene interfacial bonding. In this study, a first-principles study was performed to evaluate the feasibility of improving the Mg/graphene bonding using an in-situ formed intermediate MgO layer. The calculated interface adhesion strengths suggested a relative ordering (from high to low) of Mg(0001)/MgO(11–1) > MgO(11–1)/graphene > Mg(0001)/graphene. The enhanced Mg/MgO/graphene interface bonding can be attributed to the newly formed strong ionic and covalent interactions at the Mg/MgO and the MgO/graphene interfaces, respectively, which replace the otherwise very weak van der Waals bonding between Mg and graphene.