The hetero-structured nanoarray of CoFe₂O₄ nanosheets anchored on flaky FeSiAl with excellent microwave absorption

Hetero-structured nanoarray of CoFe₂O₄ nanosheets anchored on flaky FeSiAl was successfully fabricated by urea assisted hydrothermal synthesis. The SEM, XRD, XPS and magnetic hysteresis loops confirmed that the nanoarray oxide was a CoFe₂O₄ spinel phase. The thickness of the CoFe₂O₄ nanosheet increases with the extension of reaction time. The CoFe₂O₄ nanosheets optimized the dielectric and impedance matching of the FeSiAl composites. Interface polarization and multiple reflections of the hetero-structured nanoarray improved dielectric loss. Compared to the high aspect ratio of pure FeSiAl with poor microwave absorption, the hetero-structured nanoarray modified flaky FeSiAl can achieve better RL of − 42.7 dB and EAB of 2.96 GHz at a relatively thin thickness of 2.1 mm. The results also indicate that the objectives of thin thickness, outstanding RL and wide EAB can be achieved via the adjustment of dielectric loss originating from the construction of hetero-structured nanoarray.