Controlled synthesis of spherical and cubic magnetite nanocrystal clusters

Spherical Fe3O4 nanocrystal clusters were prepared via a simple solvothermal method using FeCl2 center dot 4H(2)O and NaOH as starting materials. When sodium acetate (NaAc) was added into the reaction system, the final products turned from sphere to cube. The as-prepared clusters are uniform in size. The possible mechanism was proposed to elucidate the changes of the clusters shape. The chemical compositions were characterized by X-ray diffraction (XRD). The morphology was determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The magnetic properties were investigated on a superconducting quantum interference device (SQUID) magnetometer. (C) 2013 Elsevier B.V. All rights reserved.