Preparation and excellent microwave absorption performance of Eu-substituted Ba 3 Co 2- x Eu x Fe 24 O 41 hexaferrites with multilayer nanoplates stacked and thickened along the c-axis

Eu substituted Ba 3 Co 2- x Eu x Fe 24 O 41 (Co 2- x Eu x Z, x = 0, 0.5, 1) hexaferrites with multilayer nanoplate stacked and thickened along the c -axis were prepared without applying an external magnetic field to improve their microwave absorption performance. The crystal phase, structure and morphology of Ba 3 Co 2- x Eu x Fe 24 O 41 (Ba 3 Co 2- x Eu x Z) hexaferrites and the electromagnetic parameters and microwave absorption performance of Ba 3 Co 2- x Eu x Z hexaferrite/paraffin composites were characterized and analyzed. The maximum effective absorption bandwidth ( EAB max ) of Co 1.5 Eu 0.5 Z reached up to 8.21 GHz (5.37 GHz - 13.58 GHz) at a coating thickness of 2.9 mm. Especially, when the coating thickness was only 3.4 mm, its EAB was 7.65 GHz (4.10 GHz - 11.75 GHz), almost covering both the C and X bands, showing the excellent low frequency absorption performance. Meanwhile, the electromagnetic wave (EMW) dissipation mechanism of the samples was surveyed and dominated by the dipole polarization, interfacial polarization, natural resonance and exchange resonance. The impedance matching and EMW absorption performance of Ba 3 Co 2- x Eu x Z hexaferrites were finely regulated by Eu substituted Co and the multilayer nanoplate stacked structure.