Magnetic, microwave absorption and structural properties of Mg–Ti added Ca–M hexaferrite nanoparticles

Abstract

The Mg2+ and Ti4+ ions substituted M-type Ca(MgTi)xFe12−2xO19 (x = 0, 0.3, 0.6, 0.9) hexagonal ferrites (x = 0, 0.3, 0.6, 0.9) were synthesized by the citrate sol–gel method. The microwave absorption, crystal structure, magnetic and morphology of the nanopowders were investigated with vector network analyzer, X-ray diffraction (XRD), vibrating sample magnetometer and transmission electron microscopy. XRD results verified the formation of M-type hexagonal structures. The particle size estimated by the Scherer formula. Results illustrated particles size is less 100 nm. The hysteresis loops showed saturation magnetization increased from 72 to 98 kA m−1 while coercive force decreased from 1710 to 428 Oe with Mg–Ti content. Microwave absorption properties measured by the standing-wave-ratio method in the Ku band frequency. The observations showed that Ca(MgTi)xFe12−2xO19 nanopowders have extraordinary microwave absorption properties. It is observed bandwidth 6.3 gigahertz (12.5–18.8 GHz with respect to − 15 dB reflection loss) for composite x = 0.6. Furthermore, the results showed a minimum reflection loss − 31.5 and − 39 dB for composites 0.6 and 0.9, respectively. It should be pointed out thickness of the composites are 1.9 mm.