Structural, magnetic and dielectric properties of green synthesized Ag doped NiFe2O4 spinel ferrite

Abstract

Ag-doped nano NiFe2O4 spinel ferrites were successfully synthesized using an environmentally friendly sol-gel technique. Comprehensive characterization of the obtained samples was carried out, employing techniques such as X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy. The results from XRD and FTIR analyses unequivocally confirmed that the synthesized samples were of high purity and in a well-defined phase. Furthermore, examination of the samples through Field Emission Scanning Electron Microscopy (FESEM) revealed the formation of spherical grains, with an average grain size of 50 nm for pure NiFe2O4 nanoparticles and an increased size of 72 nm for the Ag-doped NiFe2O4 nanoparticles. Moreover, the investigation delved into the electrical conductivity and optical properties of these nanoferrites. It was noteworthy that the electrical conductivity demonstrated a significant enhancement in the case of Ag-doped NiFe2O4, further indicating the potential for improved performance. Magnetic analysis revealed a coercivity value (Hc) of 2.27 A/m for NiFe2O4, while the Ag-doped NiFe2O4 nanoparticles exhibited long-range ferromagnetic ordering. Additionally, optical absorption experiments disclosed an energy band gap of 1.75 eV for NiFe2O4, whereas the Ag-doped NiFe2O4 showcased a reduced energy band gap of 1.256 eV. These findings collectively contribute to a better understanding of the properties and potential applications of these materials in various technological domains.