Construction of core-shell structural nickel@graphite nanoplate functional particles with high electromagnetic shielding effectiveness

Abstract

We fabricated core-shell structural nickel@graphite nanoplate (Ni@GNP) functional particles with a facile electroless plating technique, and investigated their properties. Scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and magnetic hysteresis loop tests confirm that the metal Ni are coated dominantly on the surfaces of GNP. The Ni@GNP functional composite exhibits high EMI shielding effectiveness of 57.1 dB at the frequency of 10 GHz, which is 1.54 times higher than that of the neat GNP with the same thickness of 0.3 mm. The electromagnetic shielding mechanism of the Ni@GNP functional composite is also investigated. Results demonstrate that the synergistic effect of the dielectric loss and magnetic loss contributes to the electromagnetic shielding effectiveness, and the former is predominant. In addition, the interfacial polarization loss and the internal multiple reflection further improves the absorption of electromagnetic wave. Benefitting from the advantages of structure and performance of the core and shell, the Ni@GNP functional composite shows a good application prospect in electromagnetic shielding field.