Sol-gel auto combustion synthesis of Al³⁺-Gd³⁺ ions co-doped cobalt ferrite nanoparticles for nanoelectronics applications

This study focused on investigating cobalt ferrite nanoparticles doped with trivalent Al³⁺ and Gd³⁺ ions across compositions ranging from CoFe_2-2xAl_xGd_xO₄ (x = 0.00, 0.02, 0.04, 0.06, 0.08). The nanoparticles were synthesized using the sol-gel auto-ignition method with citric acid as a chelating agent. Structural analysis via Rietveld-refined X-ray diffraction confirmed the formation of single-phase nanoparticles with a cubic spinel structure. Morphological examination through scanning electron microscopy revealed spherical-shaped grains. Elemental analysis using energy-dispersive X-ray analysis indicated consistent composition and high purity. Infrared spectra analysis verified the presence of characteristic modes typical of spinel ferrite structures. Magnetic properties assessed by vibrating sample magnetometry demonstrated soft magnetic behavior with lower coercivity. DC electrical resistivity measurements indicated a decrease in resistivity with increasing Al³⁺-Gd³⁺ co-doping, while dielectric studies showed enhanced properties in this regard. Overall, the findings suggest that these co-doped cobalt ferrite nanoparticles hold promise for applications in magneto-electronic devices.