Silver nanoparticles-decorated NiFe2O4/polyaniline ternary nanocomposite for electromagnetic interference shielding

Abstract

In this study, silver nanoparticle-embedded NiFe2O4/polyaniline ternary nanocomposites were prepared via chemical in situ polymerization. The synthesized nanocomposites were fully characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HR-TEM), four-probe resistivity (FPR), vibrating sample magnetometer (VSM), thermal gravimetric analysis (TGA), and vector network analyzer (VNA). XRD, FTIR, and HR-TEM analyses showed comprehensive structural and morphological evidences for as-prepared ternary compositions with varying particle size (~ 45 to 60 nm). The electrical conductivity of nanocomposites was significantly affected by the mixing of silver nanoparticles in FPR results. VSM study revealed that the prepared nanocomposites exhibit ferromagnetism at room temperature due to existence of ferrite nanoparticles. TGA indicated the enhanced thermal stability of the resulting products with increasing ratio of ferrite and silver contents. VNA study demonstrated the remarkable shielding performance (SE ~ 35.17 dB) of obtained samples with a sample thickness of 2.0 mm in the frequency range of 8.2–12.4 GHz, which is mainly attributed to the synergistic effect of polyaniline, nickel ferrite, and silver particles. These results indicated that these composite materials with ideal electromagnetic properties are best suited for EMI shielding applications.