Structure, magnetic, and microwave absorption properties of (MnNiCu)0.9-xCoxZn0.1Fe2O4/graphene composite powders

(MnNiCu)(0-9-x)CoxZn0.1Fe2O4/graphene composite powders (x=0.05, 0.1, 0.2, and 0.3) were prepared by onepot solution combustion synthesis method. Structure, microstructure, and magnetic and microwave absorption properties were analyzed by modern characterization methods. The X-ray diffraction patterns showed that single phase (MnNiCu)(0-9-x)CoxZn0.1Fe2O4 powders were obtained following combustion reaction without further heat treatment. The saturation magnetization was independent of Co substitution (similar to 65 emu/g), while the coercivity increased from 100 to 300 Oe. The (MnNiCu)(0.6)Co0.3Zn0.1Fe2O4/paraffin composite sample at the mass fraction of f=70 wt. % showed the maximum reflection loss of -30 dB with the effective bandwidth of 1.1 GHz at the matching thickness of 5.8 mm in Ku band. Although the maximum reflection loss decreased to -15 dB in X band with the addition of graphene, but the effective bandwidth increased to 2 GHz at the smaller matching thickness of 2.2 mm. Furthermore, the microwave absorption performance was obtained at lower mass fraction of (MnNiCu)(0.6)Co0.3Zn0.1Fe2O4/graphene powders. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, (MnNiCu)(0-9-x)CoxZn0.1Fe2O4/graphene composite powders were prepared by onepot solution combustion synthesis method and analyzed using various characterization techniques. The results showed that Co substitution had minimal effect on saturation magnetization but led to an increase in coercivity. The addition of graphene increased the effective bandwidth for microwave absorption, although it resulted in a decrease in maximum absorption in some cases.