Preparation of Ni/C composite microwave absorbers with high performance by controlling nickel source

Three Ni/C composites with different morphologies were prepared by changing nickel salt using a hydrothermal method and high-temperature pyrolysis. Results show that material defects, nitrogen doping, heterointerface, conductive network, and magnetic effect optimize impedance matching, resulting in the synergistic effect of conductivity loss, polarization loss, multiple scattering, and magnetic loss. The reflection loss of the sample prepared using nickel nitrate is -44.2 dB at 11.84 GHz and 2.4 mm thickness, and the effective absorption bandwidth is 5.2 GHz. In addition, radar cross section simulation demonstrates the excellent performance of the material in practical applications. Thus, the sample prepared using nickel nitrate is a candidate material for radar stealth and electromagnetic wave absorption.