Synthesis and characterization of maghemite nanosheets

Magnetic maghemite nanoparticles in the form of nanosheets were prepared by a topotactic transformation during the dehydroxylation of a gamma-FeO(OH) precursor. The precursor was synthesized from tetrapyridin Fe(II) chloride (Fe(py)(4)Cl-2). The nanosheets are several hundreds of nanometers wide, and less than 5 nm thick; they frequently bend and curl at the edges; they are nanocrystalline; and they are composed of smaller maghemite nanostructured domains, from a few nanometers up to several tens of nanometers wide. (C) 2010 Elsevier B.V. All rights reserved.