Facile synthesis of nitrogen-doped reduced graphene oxide/nickel ferrite hybrid nanocomposites with superior electromagnetic wave absorption performance in the X-band

[Display omitted] •Entangled structure consisting of crumpled RGO and hexagonal NiFe2O4 was observed.•Additive volumes of N2H4·H2O had notable influence on electromagnetic absorption.•The relationship between EMW absorption intensity and filler loadings was revealed.•Strong absorption, broad bandwidth and thin thickness were simultaneously achieved.•Characteristic dual absorption peaks were observed in the hybrid nanocomposites. In this work, nitrogen-doped reduced graphene oxide/nickel ferrite (NRGO/NiFe2O4) hybrid nanocomposites were synthesized by a one-pot hydrothermal method. Results manifested that the as-synthesized NiFe2O4 nanoparticles displayed hexagonal morphology with a mean size of 40 nm. Moreover, it was found that the entangled structure consisting of crumpled RGO and hexagonal NiFe2O4 nanoparticles was well constructed in the as-fabricated hybrid nanocomposites. Furthermore, the additive volumes of hydrazine hydrate and filler loadings had significant influences on the electromagnetic wave (EMW) absorption properties of obtained nanocomposites. Remarkably, the NRGO/NiFe2O4 hybrid nanocomposite with 15 mL additive volume of hydrazine hydrate showed the optimal reflection loss of −54.4 dB at 9.2 GHz (X band) under a matching thickness of 2.2 mm and maximum absorption bandwidth of 4.5 GHz (13.5–18 GHz) at a very thin thickness of only 1.5 mm. The dual absorption peaks located at the low and high frequency regions could be achieved by facilely modulating the matching thicknesses. In addition, the underlying EMW absorption mechanisms were uncovered. Therefore, our results could shed light on the design and fabrication of graphene-based dielectric/magnetic hybrid composites as light-weight and high-efficiency EMW absorbers.