One-step hydrothermal synthesis of Ni-Fe-P/graphene nanosheet composites with excellent electromagnetic wave...

Ni-Fe-P nanoparticles/graphene nanosheet (Ni-Fe-P/GNs) composites were successfully synthesized by a simple one-step hydrothermal method. Specifically, Ni²⁺ and Fe²⁺ were reduced by using milder sodium hypophosphite as a reducing agent in aqueous solution. SEM and TEM images show that a large number of Ni-Fe-P nanoscale microspheres are uniformly deposited on graphene nanosheets (GNs). At the thickness of 3.9 mm, the minimum reflection loss (RL) of Ni-Fe-P/GNs reaches -50.5 dB at 5.3 GHz. In addition, Ni-Fe-P/GNs exhibit a maximum absorption bandwidth of 5.0 GHz (13.0-18.0 GHz) at the thickness of 1.6 mm. The significant electromagnetic absorption characteristics of the Ni-Fe-P/GN composites can be attributed to the addition of magnetic particles to tune the dielectric properties of graphene to achieve good impedance matching. Therefore, Ni-Fe-P/GN is expected to be an attractive candidate for an electromagnetic wave absorber.