Thickness independent microwave absorption performance of La-doped BaFe12O19 and polyaniline composites

Absorber thickness is a crucial factor in microwave absorption performance. Therefore, the researches about the influence of thickness on microwave absorption performance have been intensively investigated. In this work, we prepared La-doped BaFe12O19 with a concentration of 0, 0.1, 0.3, and 0.5 by using co-precipitation then mixed with polyaniline by 10% wt. Morphological, structural, magnetic, and electromagnetic properties were evaluated using SEM, XRD, VSM, and VNA analysis. The doping modified all the properties of the samples and consequently enhanced their microwave absorption properties. The La-doping and polyaniline compositing possessed significance for maintaining reflection loss values for all composites when the absorber thicknesses varied in the range of 1.75-3.50 mm. The best microwave absorption performance could be found in the Ba0.9La0.1Fe12O19/poly-aniline (named La-P1) composite, with more than 90% of the incident wave being absorbed for all measured thicknesses. Effective bandwidths of the La-P1 increased when thickness decreased and reached a maximum of 2.52 GHz for the thickness of 1.75 and 2.00 mm.