▎ 摘　　要

The effects of silver (Ag) modified on reduced graphene oxide (rGO) to improve the conductivity of rGO/copper composite were investigated via first-principle calculations and experimental investigations. It is found that after Ag ions deposited on rGO, some floccule of Ag deposits are formed and covered on the surface of rGO. The microstructure of rGO@Ag/Cu becomes much more uniform with less defects. The conductivity and electrical contact resistance of rGO@Ag/Cu composite also is better than that of rGO/Cu without any Ag modification. Micro-mechanism shows that the Ag modification can enhance the interface bonding strength of rGO@4Ag/Cu(111) (W = - 3.3213 J/m(2)) from initial W = - 0.5645 J/m(2) of rGO/Cu. Electronic structure illuminates the improving conductivity and electrical contact resistance of rGO@Ag/Cu composite come from the best bridge effect of Ag ions between copper and carbon atoms. Furthermore its good electrical contact resistance is originated from the much more bonding strength of Ag-C than that of Cu-C. Thus our research can give some suggestions in the modification on graphene and the development of new electrical contact materials.