Carbon Nanotube/FeNi₃ Nanoparticle Composites for Electromagnetic Wave Absorption

Developing lightweight hybridized nanomaterials with appropriate components and controllable microstructures for high-performance electromagnetic wave (EMW) absorption is highly desired in the applications of EMW pollution protection, and electromagnetic wave interference stealth yet remains a great challenge. Here, a type of FeNi nanoparticle-decorated carbon nanotubes (CNTs) with diverse morphologies is synthesized via an economic one-pot hydrothermal process. Systematic research has been done to determine the influence of the iron–nickel ratio and alkaline conditions on the microstructures of the hybrid nanomaterials and their EMW absorption capabilities. It is noteworthy that an effective bandwidth of 4.2 GHz and a remarkable microwave absorption ability of −59.80 dB at 8.5 GHz were attained, which is attributed to the improved impedance matching and microwave absorption capability by the inherent conductivity of CNTs, the magnetic loss capability of the FeNi 3 nanoparticles, and the multiple interfacial polarizations and multiple reflections. The facile, controllable, and cost-effective fabrication approach integrates with the performance of the hybrid CNT/FeNi 3 nanocomposites, providing an effective strategy for high-performance electromagnetic wave absorption materials.