Jerome Leveneur - Article Nucleation and Growth of Fe Nanoparticles in SiO2: A TEM, XPS and Fe L-Edge XANES Investigation

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      Publication Details (including relevant citation   information):

      Nucleation and Growth of Fe Nanoparticles in SiO2: A   TEM, XPS and Fe L-Edge XANES Investigation

      Jérôme Leveneur, Geoffrey Ivan Neil Waterhouse, John V Kennedy,   James B Metson and ,David Richard Graham Mitchell

      The Journal of Physical Chemistry C Just   Accepted Manuscript

      DOI: 10.1021/jp206357c

      Abstract:

      Magnetic iron nanoparticles embedded in insulating oxides   matrices are prized targets for “on chip” magnetic sensors,   nano-flux gates and nanosolenoids. In this study, the nucleation   and growth of iron nanoparticles in the near surface region of   100 nm silica thin films (on silicon substrates) during ion   implantation and post implantation electron beam annealing was   systematically investigated by Transmission Electron Microscopy   (TEM), X-ray photoelectron spectroscopy (XPS) and Fe L-edge X-ray   Absorption Near Edge Spectroscopy (XANES). Results show the   presence of Fe oxides after low-fluence low-energy ion   implantation in SiO2, suggesting that initially Fe   substitutes for Si in the silica matrix. Larger Fe fluences lead   to the formation of sub-2 nm metallic Fe nuclei.   Post-implantation annealing transformed the dispersed cationic Fe   species into metallic Fe nanoclusters (diameter 1-10 nm) that are   stabilized by a thin passivating surface oxide film. The   versatility of ion implantation and electron beam annealing for   the synthesis iron nanoparticles in silica matrices is   demonstrated.

      Address (URL): http://pubs.acs.org/doi/abs/10.1021/jp206357c