Performance of open-cell foam of Cu-Ni alloy integrated with graphene as a shield against electromagnetic interference

Open-cell foam of a Cu-Ni alloy integrated with graphene was used as a lightweight, multilayered, electromagnetic interference (EMI)-shielding material. It was prepared by electroless copper plating, then nickel electroplating, and finally electrophoretic deposition of a graphene nanosheet (GNS). The foamed Cu-Ni-GNS composite comprises, from the inside to the outside, Cu, Ni, and GNS layers. The morphology and EMI performance in the 8-12 GHz range were characterized and studied, respectively. The results indicate that the shielding effectiveness of the composite increased with increasing pore density (measured in pores per inch) and increasing thickness. The porous structure of the composite could attenuate the incident electromagnetic microwaves by reflecting, scattering, and absorbing them between the metallic skeleton and the GNS layer. This multilayered foamed composite is a potential material for applications in which shielding and ventilation are required.