Coralliform Li0.35Zn0.3Fe2.35O4/polyaniline nanocomposites: Facile synthesis and enhanced microwave absorption properties

Highlights: • Li_0.35Zn_0.3Fe_2.35O₄/PANI nanocomposites are prepared by interfacial polymerization. • Coralliform PANI are grafted onto Li_0.35Zn_0.3Fe_2.35O₄ by in-situ polymerization. • The bandwidth of R_L exceeds −10 dB in the frequency is 4.24 GHz. • The sample prepared has R_L lower than −36.9 dB at 12.4 GHz. • The mechanism relies on interfacial polarization and impedance matching. Coralliform polyaniline (PANI) nanorods were successfully grafted onto the surface of Li_0.35Zn_0.3Fe_2.35O₄ (LZFO) particles by interfacial polymerization. The LZFO particles were prepared by sol-gel method and decorated via the coralliform PANI nanorods. The structure and morphology were systematically investigated by Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM/TEM). The LZFO/PANI nanocomposite with novel coralliform microtopography was prepared by using an efficient, simple, and controllable two-step method. The electromagnetic parameters with different weight ratios of ferrite and aniline monomer were investigated at the 0.5–18 GHz frequency range by using vector network analyzers. Reflection loss (R_L) of different thicknesses was calculated using the electromagnetic parameter according to the transmission line theory. The LZFO/PANI nanocomposite, optimized with a weight ratio of 1:2 of ferrite to aniline monomer, showed that the maximum R_L value reached −36.9 dB at 12.4 GHz with the thickness of 2.1 mm, and the bandwidth below −10 dB was at 4.24 GHz (11.26–15.5 GHz). The enhanced microwave absorption properties of LZFO/PANI nanocomposites were chiefly attributable to the coralliform structure and improved impedance matching between the dielectric and magnetic loss. This study proves that LZFO/PANI nanocomposites can be a potential candidate for efficient microwave absorption materials.