Manganese and cobalt substituted ferrite nanoparticles synthesized via a seed-mediated drip method

Abstract To produce multi-dopant ferrite nanoparticles, the ‘Extended LaMer’ and seed-mediated growth techniques were combined by first utilizing traditional thermal decomposition of metal acetylacetonates to produce seed particles, followed by a continuous injection of metal oleate precursors to increase the volume of the seed particles. With the choice of precursors for the seeding and dripping stage, we successfully synthesized particles with manganese precursor for seeding and cobalt precursor for dripping (Mn_0.18Co_1.04Fe_1.78O₄, 17.6 ± 3.3 nm), and particles with cobalt precursors for seeding and manganese precursors for dripping (Mn_0.31Co_0.74Fe_1.95O₄, 19.0 ± 1.9 nm). Combining transmission electron microscopy, energy-dispersive x-ray spectroscopy, x-ray diffraction, and vibrating sample magnetometry, we conclude that the seed-mediated drip method is a viable method to produce multi-dopant ferrite nanoparticles, and the size of the particles was mostly determined by the seeding stage, while the magnetic properties were more affected by the dripping stage.