Temperature dependent magnetic and microwave absorption properties of doubly substituted nanosized material

Abstract

The sol gel method has been adopted to synthesize a series of X-type hexagonal ferrites with concentration Sr2−x Gdx Ni2 Fe28−yCdyO46 (x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10 and y=0, 0.1, 0.2, 0.3, 0.4, 0.5). The XRD analysis reveals the single phase of the prepared material and the lattice constants a (Å) and c (Å) varies with additives. The crystallite size of the present investigated ferrite is found in the range of 20–30nm measured from TEM image. The enhancement in the magnetic properties (saturation magnetization, remanance magnetization and coercivity) can be observed with the increase of dopping concentration and the coercivity lies in the range of (484.22–887.47) G. The saturation and remanance magnetization decreases monotonically with the temperature which is the characteristic of the hexagonal ferrites. The Gd–Cd substituted sample possesses low values of complex relative permittivity and permeability than the pure samples. The material exhibits maximum microwave absorption −23dB at 11.87GHz and attenuation peak is in good agreement with the reflection loss value. The microwave absorption properties reflect the applications of this material in super high frequency devices (SHF).