Electromagnetic and microwave absorbing properties of polyaniline-Co0.5Zn0.5La0.1Fe1.90O4 composites in the 8.2-12.4 GHz frequency range

In this paper, the polyaniline (PANI) and PANI-Co0.5Zn0.5La0.1Fe1.9O4 (x wt %, x = 10 and 20) composites were synthesized by an in situ polymerization. X-ray diffraction (XRD), scanning electron microscope (SEM) and ultraviolet-visible spectrometer (UV-vis) were used to characterize the morphologies and phase formation of the prepared products. The dielectric loss (tan epsilon) and the magnetic loss (tan mu) of the samples were measured in X-band (8.2-12.4 GHz) by using vector network analyzer (HB8510B). The results demonstrated that the dielectric loss of PANI-Co0.5Zn0.5La0.1Fe1.9O4 were lower than that of the pure PANI and vice versa for magnetic loss. Furthermore, the dielectric loss and magnetic loss of the composites decreased and increased respectively, when the relative content of Co0.5Zn0.5La0.1Fe1.9O4 increased. In the measuring frequency range of 8.2 similar to 12.4 GHz, the reflection loss of composites increased with an increase in Co0.5Zn0.5La0.1Fe1.9O4 relative content. PANI-Co0.5Zn0.5La0.1Fe1.9O4 (20 wt %) composite has the highest reflection loss in the range of -8.73 dB to -12.75 dB, with a maximum reflection loss value at -12.75 dB at the frequency of 11.0 GHz (full frequency width at about half of the peak response). In the measuring frequency range of 8.2 similar to 12.4 GHz, with the increase of Co0.5Zn0.5La0.1Fe1.9O4 relative content, the reflection loss of composites increased, and the PANI-Co0.5Zn0.5La0.1Fe1.9O4 (20 wt%) composite has the highest reflection loss, which is in the range of -8.73 dB to -12.75 dB, and the maximum values of the reflection loss is -12.75 dB at the frequency of 11.0 GHz. (full frequency width at about a half of the peak response).