Microwave absorption properties of 50% SrFe12O19–50% TiO2 nanocomposites with porosity

Abstract

SrFe12O19–TiO2 nanocomposites are usually used for absorbing microwaves in military and civil applications. In this work, microwave absorption properties of porous SrFe12O19 nanocomposites with 50% weight ratio of TiO2 have been investigated. 50% TiO2–50% SrFe12O19 nanocomposites were prepared by a controlled hydrolysis of titanium tetraisopropoxide in which SrFe12O19 nanoparticles were synthesized by a sol–gel auto combustion route. The morphology, crystalline structure and crystallite size of SrFe12O19–TiO2 nanocomposites were characterized by field emission scanning electron microscopy and X-ray powder diffraction. The magnetic measurements were carried out with a vibrating sample magnetometer. The microwave absorption was measured by a Vector Network Analyzer. The microwave absorption results indicated that the reflection losses for specimens with 52%–56% porosity and thicknesses of 1.8, 2.1 and 2.6mm were not very low but minimum reflection loss for a specimen with 4.2mm thickness reached upto −33dB.