High-efficiency microwave absorber based on carbon Fiber@La0.7Sr0.3MnO@NiO composite for X-band applications

Abstract

Carbon fiber (CF) as a multifunctional material with superb performance in aviation industry has serious drawback such as impedance mismatch which restricted the capability of using it as microwave absorber materials. In this research, a novel hierarchical carbon fiber@La0.7Sr0.3MnO@NiO (CF/LS/N) composite was facilely and successfully synthesized via sol-gel and subsequent hydrothermal reactions. The structural, morphological, magnetic and electromagnetic behavior of the composite were precisely evaluated via XRD, FESEM, XPS, VSM and VNA analysis. According to the systematic evaluation results, the synergistic positive effect of adding NiO nanoparticles is revealed in improving the microwave absorption performance of CF@La0.7Sr0.3MnO composite. Literally, dielectric features of the prepared composite enhanced by introducing NiO nanoparticles. Due to improvement in impedance matching, dipole polarization, multiple reflection/scattering, eddy current, interfacial polarization and magnetic resonance phenomenon the minimal reflection loss of the obtained hybrid composite reach to -26 dB with 2.6 mm thickness at filler content of 20 wt%. CF/LS/N composite is predictable to be suitable candidate for military purposes because of the lightweight, low cost and outstanding absorbing properties.