Impact of rare earth cerium (Ce) substitution on structural, magnetic and electrochemical properties of lithium ferrites: A comprehensive study

Abstract

Sol-gel technique using metal nitrates and citric acid has been employed to synthesize lithium ferrites by the substitution of cerium which is formulated as (Li₀.₅Ce_xFe₂._5-xO₄) (x = 0, 0.05, and 0.10). The purpose of this research is to understand how Ce substitution modifies the physical characteristics of lithium ferrites. Various experimental techniques including X-ray diffractometers (XRD) for structural determination, Fourier transform infrared (FTIR) spectroscope to examine characteristic bands in materials and scanning electron microscope (SEM) to evaluate the materials morphology, are used to characterize the produced ferrites. Moreover, for the investigations of magnetic properties of samples including saturation magnetization (Ms) and coercivity (Hc) along with retentivity (Mr), vibrating samples magnetometer (VSM) was utilized. X-ray diffraction analysis verified FCC, a single-phase structure, and a rise in lattice constant (or parameter) from 8.37 Å to 8.53 Å with the increase of Ce concentrations. The nanoparticles are seen to be aggregated and to have varying sizes in scanning electron micrographs. A look at the FTIR spectrum reveals that the octahedral B-site absorbs light at a wavelength of 652–663 cm⁻¹. As Cerium is added to pure lithium ferrite, the band shifts towards higher frequency. CV measurements show that the specific capacitance decreases with increasing scan rate, leading to a commensurate increase in the loop area. The CV analysis shows that the investigated material can be used as electrode material for storage devices.