Investigation of stable dielectric permittivity with superior EMI shielding capabilities of a multifunctional NiFe2O4@MoS2 nanomaterial

This study presents a multifunctional NiFe2O4@MoS2 nanomaterial synthesized by coprecipitation and hydrothermal methods. The highly magnified Field emission scanning electron microscopic (FESEM) images expose an excellent interconnected network of MoS2 petals and NiFe2O4 cores. NiFe2O4@MoS2 nanomaterial's crystalline arrangement and phase purity are explored using X-ray diffraction (XRD) analysis. A comprehensive analysis of the NiFe₂O₄@MoS₂ nanomaterial, focusing on its dynamic electrical properties across a temperature zone of 183 K to 373 K. The temperature-dependent impedance and modulus plots versus frequency reveal insights into the material’s conduction and relaxation. Electrical characteristics verify the contribution of electroactive regions, such as grains and surfaces, by the use of impedance spectroscopy. An analogous circuit model is used to measure different electrical characteristics. Using an adiabatic small polaron hopping model, the activation energies of bulk (0.32 eV) and various cations (0.30 eV) are estimated. Using Mott's variable range hopping model, the hopping length at the interface is calculated to be between 1.8 and 1.5 Å. Stable dielectric permittivity is explained on the basis of the polarizability of the cations and tangent loss. The NiFe2O4@MoS2 nanomaterial showcases total electromagnetic interference (EMI) shielding effectiveness of 30.6 dBs around the 11GHz frequency range with a thickness of 3 mm.