Metal carbide/Ni hybrids for high-performance electromagnetic absorption and absorption-based electromagnetic interference shielding

Abstract

Electromagnetic absorption and electromagnetic interference (EMI) shielding materials, especially absorption-based EMI shielding materials, are urgently desired to eliminate increasingly serious electromagnetic radiation pollution. Metal carbides exhibit great promise in realizing excellent EMI shielding owing to their outstanding electrical conductivity. However, because of the same reason, the electromagnetic wave reflection from the metal carbide films is hardly diminished and thereby metal carbides cannot realize absorption-based EMI shielding. Herein, metal carbide/Ni hybrid nanostructures are designed to realize electromagnetic absorption and absorption-based EMI shielding. The hybrid nanostructures are prepared by in situ reduction of Ni on metal carbide nanosheets. The loading of Ni greatly increases the impedance matching and attenuation constants. Metal carbide/Ni hybrids achieve a reflection loss of −41.7 dB at 10.8 GHz with a thickness of 1.8 mm. An EMI shielding effectiveness larger than 60 dB is achieved in the whole X-band with a metal carbide/Ni hybrid film of 50 μm. Particularly, the absorption contributes 98.9% of total EMI shielding effectiveness, indicating the absorption-based EMI shielding. In addition, the metal carbide/Ni hybrid film exhibits very good mechanical properties and long-term stability in water. Our findings are very important for the development of electromagnetic absorption and absorption-based EMI shielding materials.