Versatile seed-mediated method of CoxFe3-xO4 nanoparticles synthesis in glycol media via thermal decomposition

Series of CoxFe3-xO4 with x = 0.0, 0.5 and 1.0 were synthesized by novel seed-mediated method in glycol media. Nanoparticles gradually change their structure from monocrystalline seeds of 6–7 nm size to polycrystalline nanoclusters of 26–33 nm size while crystallite size grows from 5 to 6 nm to 8–10 nm. All series of initial seeds as well as subsequent iron oxide nanoparticles show superparamagnetic behavior whereas other 1st and 2nd series with x = 0.5 and 1.0 show ferrimagnetic behaviour. Coercitive force of Co0.5Fe2.5O4 have comparable or even higher values than CoFe2O4 while saturation magnetization value close to iron oxide samples of same size. The proposed method may be perspective for synthesis of ferrites with controlled size, structure and Co to Fe ratio.