Facile synthesis and magneto-alignment effect on the microwave absorption property of NiCo2O4/NiO/Co3O4 composites

[Display omitted] •A simple method of high temperature ignition to metalorganics was successfully used to synthesize composites of NiCo2O4, NiO, and Co3O4.•Through the introduction of a magnetic field tuning method during the fabrication process, NiCo2O4, NiO, and Co3O4 nanoparticles are arranged closely in epoxy resin. This modification enhances the magnetic exchange interactions within the material, thereby improving both dielectric loss and magnetic loss characteristics. As a result, the minimum reflection loss RL values is up to −45.11 dB with an effective bandwidth of 4 GHz.•This paper presents a straightforward method to heighten the microwave absorption performance of NiCo2O4 by modifying the macroscopic order and degree. A simple method of high-temperature ignition to metalorganics was successfully used to synthesise composites of NiCo2O4, NiO and Co3O4. A detailed investigation of the composite’s microwave absorption properties revealed the magneto-alignment effect. By closely arranging NiCo2O4, NiO and Co3O4 nano-particles in epoxy resin, the magnetic exchange is strengthened under the influence of a magnetic field. The sample without magnetic alignment, S0, exhibited poor absorption efficiency with reflection loss (RL) values hardly reaching − 10 dB across a frequency range of fixed and different thicknesses (2–18 GHz). In comparison, the oriented composite exhibited higher permittivity and permeability, particularly in the high-frequency range. Considering the improved impedance matching and reasonable adjustment of dielectric and magnetic losses, the microwave absorbing performance of the oriented composite substantially improved in the 10–14 GHz range. The minimum RL is reduced to − 45.11 dB with an effective bandwidth of 4 GHz. Herein, we present a straightforward method to increase the microwave absorption performance of NiCo2O4 by modifying the macroscopic order and degree.