The first principle study of the effect of Co dopant and C/Cu vacancy defect on the interfacial bonding of graphene-copper composites

Abstract

The effect of substitutional Co dopant and C/Cu vacancy defect on the interfacial bonding between graphene (Gr) and copper (Cu) layer has been studied by the first-principle calculation. The result shows that the bonding energy of the Gr–Cu interface with Co dopants is lower than that without Co dopants, which implies that the Co dopants make the interface bond more easily occurring and more stable. And the bonding energy of the interface with one Co atom is smaller compared to that of the interface with two Co atoms, which indicates that low concentration of Co dopants is the more favorable situation at the Gr–Cu interface. It is found that the C/Cu vacancy defect plays a positive role in the process of Co promoting the Gr–Cu interface bonding. When one Co atom is doped into the Gr–Cu interface with C vacancy, the interfacial bonding energy is the smallest for −4.09 eV among all the interfaces, which indicates the interface is the easiest to combine and the most sable. The results show that it will enhance the interface bonding to dope low concentration Co atom into the Gr–Cu interface and to form C/Cu vacancy defect during preparing the Gr–Cu composites.