Enhanced Electromagnetic Interference Shielding Effects of Cobalt-Nickel Polyalloy Coated Fabrics with Assistance of Rare Earth Elements

Co-Ni-P coatings were prepared on ramie fabric by electroless plating with addition of rare earth (RE: Ce, Pr, and Nd). The proposed ultra-low-cost and easy-operated electroless plating method involved successive steps, namely, alkali mercerization, malic acid modification, Co nanoparticles activation, and Co-Ni-P deposition. FT-IR and XPS measurements were utilized to verify the functions of modification and activation procedures. Refined effects of Ce, Pr, and Nd on the structures and morphologies of resulting Co-Ni-P coatings were demonstrated by XRD and FE-SEM measurements. Moreover, by adding tiny dose of RE into the one-pot plating solution, electroless deposition rates were substantially accelerated in all cases. With regard to the resulting fabric-based Co-Ni-P coatings obtained in the presence of RE, not only mechanical durability but also chemical stability were improved. All Co-Ni-P coated fabrics displayed admirable electromagnetic properties and high electromagnetic interference (EMI) shielding effectiveness (SE). Owing to the benefits from RE, EMI SE values of Co-Ni-P shielding fabrics were enhanced with increment of 3-11 dB ranging from 30 to 6000 MHz. Significantly, Co-Ni-P-Nd coated fabric with uniform surface morphology and outstanding corrosion resistance possessed the highest EMI SE of 42.27-66.76 dB.