Effect of Mg2+ on Enhancing Stabilization and Microwave Absorption Performance of MgxFe3−xO4

Magnetite (Fe₃O₄) is an essential material for enhancing microwave absorption performance and is widespread and abundant as a solid solution in natural minerals and metallurgical slags. In this work, the effect of Mg²⁺ on the structure, stabilization, and microwave absorption performance of magnesium-containing magnetite (Mg_xFe_3-xO₄) was investigated. On the basis of experiments on the reactions of Fe₂O₃ and MgO under different levels of <i>p</i>_CO/(<i>p</i>_CO + <i>p</i>_CO2), Mg_xFe_3-xO_{4 (x=0.0,0.2,0.4,0.6,1.0)} was synthesized, and Mg²⁺ was found to inhibit the re-oxidation of magnetite. On this basis, the microwave absorption performance of various synthesized Mg_xFe_3-xO₄ samples was measured and analyzed, where Mg²⁺ was found to enhance the microwave absorption performance of Fe₃O₄, and the RL_min value of Mg_0.2Fe_2.8O₄ increased to -50.43 dB compared to that of -19.20 dB for Fe₃O₄. Furthermore, the enhancement mechanism of Mg²⁺ was revealed through impedance matching, dielectric and magnetic loss tangents, and magnetization curves, where the Mg²⁺ ions were found to accelerate the hopping of electrons and change the impedance matching of Mg_xFe_3-xO₄ to a more ideal state.