Lightweight nickel foam coated with multi-walled carbon nanotubes for enhanced electromagnetic interference shielding: experimental and multiphysics evaluation

This study presents the development and performance evaluation of a lightweight, multi-layered electromagnetic interference (EMI) shielding material composed of open-cell nickel (Ni) foam integrated with multi-walled carbon nanotubes (MWCNTs). While previous works have investigated CNTs or metallic foams separately, a systematic analysis combining dip-coated CNTs on Ni foams with Multiphysics simulations remains scarce. Addressing this gap, the Ni foam (100 PPI) was coated with MWCNTs at two concentrations (16 mg/mL and 20 mg/mL) using a dip-coating method in polyvinyl alcohol. Samples were tested over 800–3,000 MHz. The 20 mg/mL CNT-coated sample (F1) exhibited the highest shielding effectiveness (SE) of 48.165 dB, outperforming the uncoated and 16 mg/mL samples. COMSOL Multiphysics simulations confirmed and extended the experimental findings, validating the effectiveness of the porous Ni-CNT structure in attenuating electromagnetic waves through reflection, absorption, and scattering. The study bridges the experimental-simulation gap and identifies CNT concentration as a critical design parameter for scalable EMI shielding solutions.