Spherical iron oxide particles synthesized by an aerosol technique

Spherical particles of several iron oxides have been obtained by pyrolysis of an aerosol generated by ultrahigh frequency spraying of a solution. Two different precursor solutions were used to produce the aerosol: Fe(NO₃)₃ · 9H₂O and FeC₆H₅O₇ · 4H₂O. The iron nitrate decomposition leads to the formation of α-Fe₂O₃, while the organic precursor pyrolysis leads to magnetic particles of either γ–Fe₂O₃ or Fe₃O₄. Structural phase, particle size, texture, and homogeneity of the products so obtained can be controlled as a function of some synthesis conditions such as precursor solution, temperature, solution concentration, and surrounding atmosphere.