Co-deposition and thermal conductivity of nickel–graphene composite coatings on copper surface

Galvanostatic electrochemical co-deposition was used to fabricate nickel-based reduced graphene oxide (Ni–rGO) nanocomposite by varying the current density in the range of 3–6 Adm−2 and at rGO loading of 1 g L−1. The process relies on the reduction of oxygenated functional groups of GO. By excessive incorporation and simultaneous reduction of GO in the structure of Ni–rGO composite coatings, the morphology transforms into structure with rough and three-dimensional (3D) features. The formation of Ni–rGO composite coatings was confirmed by investigating 3D morphology by SEM and XRD studies. Furthermore, comprehensive investigation of the thermal diffusivity, density, specific heat capacity, and thermal conductivity of Ni–rGO composite was conducted. Moreover, the relationship between current density and thermal conductivity was also evaluated. The test results indicate that the prepared Ni–rGO composite exhibits excellent thermal conductivity when the current density is 5 A dm−2. Combined with the outstanding performance of corrosion resistance in the early stages, the as-prepared Ni–rGO composite coatings are highly promising for cooling systems in ship and heat dissipation system in ocean electronic equipment.