▎ 摘　　要

Carbide/carbon composites are new types of electromagnetic (EM) wave absorbing materials because of their good stability, light weight, easy synthesis and excellent performance. In this work, monodisperse branched nickel carbide (Ni3C) nanoparticles with controlled morphology were fabricated through high-temperature pyrolysis of nickel acetylacetonate under anhydrous and oxygen-free conditions. Then Ni3C nanoparticles were uniformly in situ grown on the surface of reduced graphene oxide (rGO) to form nickel carbide/reduced graphene oxide (Ni3C/rGO) nanocomposite. Series of characterization and performance tests were conducted, and the results showed that the EM wave absorption performance of Ni3C/rGO composite was greatly enhanced compared with that of pure phase Ni3C nanoparticles. Due to the combined effects of interfacial polarization loss, conductivity loss and surface defects, Ni3C/rGO nanocomposite exhibited strong reflection loss in 2-18 GHz band, which could attenuate the EM waves incident to the internal loss to a greater extent. When the Ni3C/rGO composite is at 3.5 mm thickness, the maximum effective absorption bandwidth can reach 3.6 GHz, and at 3.0 mm thickness, the lowest reflection loss value can reach - 42.8 dB. This high-performance nanocomposite can be a new candidate material for EM wave absorption. (C) 2021 Elsevier B.V. All rights reserved.