Nanoparticles of Ni_1-x Zn_x Fe₂ O₄ used as Microwave Absorbers in the X-band

Ferrites nanoparticles of Ni_1-xZn_xFe₂O₄ ferrites with x varying between 0 and 1, in steps of 0.2, were obtained by solution combustion synthesis (SCS) and dispersed in oil paint at the concentrations of 10, 20, 30 and 40% by ferrite weight of ferrite, with the aim of producing electromagnetic wave absorbing composites, in the X band (8-12 GHz). The ferrite powders obtained were characterized by X-ray diffraction (XRD), and to determine to mean crystallite size, crystallographic phases, as well as lattice parameters, was used the Rietveld method. The XRD results revealed the majority presence of the spinel cubic ferrite phase for all stoichiometries with crystallite size between 44 and 81 nm. The composites were characterized by the rectangular waveguide transmission line method to measure the absorption of the electromagnetic wave in the X band. The nanocomposites with 40% of NiFe₂O₄ and Ni_0.8Zn_0.2Fe₂O₄ presented the highest electromagnetic wave absorption performance.

Keywords:
Ni-Zn ferrite nanoparticles; electromagnetic radiation absorbent materials (RAM); solution combustion synthesis (SCS).