Role of Fuel and Their Ratio with Metal Nitrates in Combustion Synthesis of Spinel Ferrite Nanoparticles

Spinel ferrite magnetic nanoparticles were synthesised by the sol–gel auto-combustion method using glycine and citric acid as fuels. The fuel-to-metal nitrate ratio was adjusted based on the oxygen balance of the reaction. A comparative study was carried out to investigate the effect of fuel type on the structural properties of cobalt ferrite nanoparticles. The phase formation, crystallinity, and structural parameters of the synthesised samples were analysed using X-ray diffraction (XRD). The XRD results confirmed the formation of single-phase cubic spinel cobalt ferrite without any secondary phases. Variations in crystallite size and lattice parameters were observed depending on the type of fuel used, indicating that the combustion behaviour significantly influences the structural characteristics of the material.