Fabrication of hollow core-shell NiCo2O4@polypyrrole nanofibers/reduced graphene oxide ternary composites with excellent microwave absorption performances

NiCo-HFPR-0.2 composite is prepared for high-performance electromagnetic wave absorption, exhibiting the RLmin of −61.20 dB at 14.26 GHz and 1.56 mm, the EAB of 4.90 GHz at 1.57 mm, and the reduction in RCS up to 31.0 dB m2 at θ=0°. [Display omitted] •NiCo-HFPR-0.2 composite is successfully fabricated for electromagnetic wave absorption.•The composite has the RLmin of −61.20 dB at 14.26 GHz and 1.56 mm and the EAB of 4.90 GHz at 1.57 mm.•These performances are attributed to the multiple losses and impedance match stemming from reasonable structural design.•At θ = 0° and Phi = 0°, the coating of this composite reduces the RCS value by 31.0 dB m2 compared to the sole PEC layer. In contemporary times, electromagnetic radiation poses a significant threat to both human health and the normal functioning of electronic devices. Developing composites as adsorption materials possess exceptional electromagnetic wave absorption performances can efficient address this critical issue. Herein, hollow core–shell NiCo2O4@polypyrrole nanofibers/reduced graphene oxide (NiCo-HFPR) composites are fabricated by the combination of electrostatic spinning, air calcination, in-situ polymerization, freeze-drying and hydrazine vapor reduction. As anticipated, NiCo-HFPR-0.2 exhibits noteworthy properties, with the minimum reflection loss (RLmin) of −61.20 dB at 14.26 GHz and 1.56 mm, as well as the effective absorption bandwidth (EAB) of 4.90 GHz at 1.57 mm. Additionally, the simulation procedure is employed to determine the radar cross-section (RCS) attenuation. In comparison to a singular perfect electrically conductive (PEC) layer, the PEC layer coated with NiCo-HFPR-0.2 consistently yields an RCS value below −10 dB m2 within the range of −60° < θ