One-step solvothermal synthesis of hollow Fe3O4/single walled carbon nanohorns composites with excellent microwave absorption properties

With the increasingly serious electromagnetic radiation and pollution, high-performance microwave absorption materials are urgently needed. In this work, the hollow Fe3O4/single-walled carbon nanohorns (SWCNHs) composites have been synthesized through one-step solvothermal method. The compositions, morphologies, microstructures, and microwave absorption performance of the hollow Fe3O4/SWCNHs composite have been comprehensively investigated. Benefitting from the unique hollow spherical structure and synergistic effects of dielectric loss and magnetic loss, the as-obtained hollow Fe3O4/SWCNHs composite exhibits an optimum reflection loss of −46.9 dB at 16.8 GHz with a matching thickness of 1.5 mm, and a broad effective absorption bandwidth of 7.21 GHz ranging from 10.79 to 18 GHz with a thickness of 2.0 mm, suggesting that the hollow Fe3O4/SWCNHs composite can be used for high-efficiency microwave absorption. [Display omitted] •The hollow Fe3O4/SWCNHs composite was synthesized through one-step solvothermal method.•The composite has peculiar hollow spherical structure and excellent microwave absorption performance.•The composite shows an optimum reflection loss of −46.9 dB and a broad effective absorption bandwidth of 7.21 GHz.•The composite can be used for high-efficiency microwave absorption.