High Tensile Properties and Low Surface Roughness of Gr/Cu Foils

Cu foil with low surface roughness and high tensile properties is a challenge in the field of electronic materials. In this research, the graphene/copper foils (GrCFs) have been fabricated by direct current electrodeposition. The changes in the structure and properties of GrCFs caused by mechanical agitating rate were investigated. XRD, SEM, laser scanning confocal microscopy and tensile equipment were employed to examine surface quality, surface roughness, microstructure and tensile property of GrCFs. The results indicated that the electrodeposition particles became denser and larger, and the deposition rate increased with increasing the mechanical agitating rate. However, the surface roughness (Ra) of the GrCFs decreased from 3.49 ± 0.06 to 0.90 ± 0.06 μm and then increased to 1.59 ± 0.05 μm. When the CuSO₄·5H₂O concentration was 70 g/L and the mechanical agitating rate was 200 rpm, the minimum surface roughness of 0.90 ± 0.06 μm and the maximum tensile strength of 558 ± 29 MPa were simultaneously obtained. The enhancement of tensile strength of GrCFs was primarily ascribed to the refinement of the crystalline size and the Gr reinforcement. The surface roughness of GrCFs was dominated by an appropriate agitating rate and Cu²⁺ concentration.