High electrical conductivity of Cu wires cladded by Gr/Cu coating

Graphene/copper (Gr/Cu) coating-cladded copper (Cu) wires with high electrical conductivity and low surface roughness were successfully prepared from copper (II) sulfate pentahydrate (CuSO 4 ·5H 2 O) containing graphene (Gr) ranging from 0 to 2.0 g/l by direct current electrodeposition. The Gr defect density, surface morphology, surface roughness and electrical conductivity of Gr/Cu coating-cladded copper wires were investigated. The results revealed that with increasing Gr concentration, the surface roughness and electrical conductivity of Gr/Cu coating-cladded copper wires were enhanced simultaneously. When the Gr concentration was 1.2 g/l, Gr/Cu coating-cladded copper wires possessed the lowest surface roughness of 4.241 μm and the highest electrical conductivity of 105.5% International Annealed Copper Standard. Compared with the counterpart without Gr, the surface roughness was reduced by 10.7%, and the electrical conductivity was increased by 5.4%. Models were developed to evaluate the surface roughness and electrical conductivity of Gr/Cu coating-cladded copper wires.