Mukhtar Ahmad
COMSATS Institute of Information Technology, Pakistan
Title: Synthesis and characterization of Zn-substituted lithium cobalt ferrite using sol-gel autocombustion for a cathode material in lithium ion batteries
Biography
Biography: Mukhtar Ahmad
Abstract
Li-ferrites are scientifically advanced smart materials and their structural and magnetic properties can be modified for a particular application by controlling the synthesis conditions and better choice of metal ions. In the present work, single phase samples of lithium zinc ferrites with general formula LiCo0.5-xZnxFe2O4 (where 0≤x≤0.5) were synthesized by sol gel auto combustion method. To study the mass loss (%) and endothermic and exothermic reactions as a function of temperature, thermal analyses (TGA/DTA) were carried out for a selected sample. The structure and morphology for all the samples were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD patterns confirm that all the samples retain phase purity of spinel structure when substituted with Zn contents in place of Co ions. However, the structural parameters such as lattice constant, cell volume and X-ray density were altered after Zn-substitution into the spinel lattice. The SEM images show that the grain size estimated by line intercept method was found to be unchanged by substituting Zn ions because the values of ionic radii of Zn and Co are almost equal. The M-H loops for all the samples show a low value of coercivity (a few hundred oersteds) which confirms the soft magnetic nature of these ferrites. Moreover, the values of saturation magnetization and remenance are in good agreement with earlier reported values for this structure. The observed parameters suggest that these ferrites may be potential candidates for a cathode material in Li-ion batteries, core materials and microwave devices.