Size and shape-controlled synthesis and characterization of CoFe2O4 nanoparticles embedded in a PVA-SiO2 hybrid matrix

This study presents the controlled synthesis and characterization of CoFe2O4 nanoparticles embedded in a PVA-SiO2 hybrid matrix. The sol-gel method consists in the embedding of reactants (Co and Fe nitrates and 1,4-butanediol) in a matrix containing high molecular weight poly(vinylalcohol) and tetraethylorthosilicate, and in the formation and decomposition of succinate precursors followed by a controlled thermal decomposition (400-1000 °C). The thermal analysis and Fourier transformed infrared spectroscopy confirmed the formation of succinate precursors and hybrid matrix, while X-ray diffraction indicated the formation of single phase CoFe2O4. Transmission electron microscopy revealed the shape and size of CoFe2O4 nanoparticles, while scanning electron microscopy indicated the morphology of CoFe2O4/SiO2-PVA particles. The particle size of ferrite is critically dependent on the annealing temperature and CoFe2O4:PVA-SiO2 molar ratio.