Effect of electroless nickel plating on electromagnetic interference shielding effectiveness of pitch-based carbon papers/epoxy composites

To develop high-quality electromagnetic interference shielding efficiency (EMI SE) materials, nickel-pitch-based carbon papers (Ni-PCPs) were prepared using an electroless nickel-plating method and a wet-laid process to obtain Ni-PCPs/epoxy composites with enhanced EMI SE. The morphologies and structural properties of Ni-PCPs were determined using scanning electron microscopy and x-ray diffraction. It was found that the intensity of the metallic Ni peak increased with increasing Ni-plating time. In the frequency range of the electromagnetic waves from electrical appliances (0.5-1.0 GHz), the 5Ni-PCPs/epoxy composites of 0.25 mm thickness exhibited high EMI SE. The EMI SE of the composites was measured according to ASTM D4935-99 and increased in proportion to the current density because of the role of Ni particles. This result implies that the presence of Ni on the pitch-based carbon fibers can lead to good EMI SE, owing to the EMI adsorption behaviors of the metal particles.