Production of magnetite by electrolytic reduction of ferric oxyhydroxide

Magnetite (Fe3O4) particles were prepared by electrolytic synthesis without the use of a surfactant. Various techniques were used to evaluate the effect of two parameters, the current density and the separation between electrodes, in the formation process of ferrimagnetic magnetite particles. The crystallite sizes can be controlled by adjusting the current density. Particle formation was favored below a critical separation distance between the electrodes. Finally, a formation mechanism for magnetite was proposed based on the partial reduction of lepidocrocite. (C) 2015 Elsevier B.V. All rights reserved.