Combination of the surfactant-free nonaqueous sol–gel approach with the microwave technique makes it possible to synthesize Fe3O4, CoFe2O4, MnFe2O4, and NiFe2O4 nanoparticles of about 5–6 nm and with high crystallinity and good morphological uniformity. The synthesis involves the reaction of metal acetates or acetylacetonates as precursors with benzyl alcohol at 170 C under microwave irradiatio...