X-ray absorption analysis of core/shell magnetic (Fe,Co)–B nanoparticles of amorphous and crystalline structure obtained by chemical reduction

DOI: 10.1016/j.jnoncrysol.2006.12.096

Authors: L. Fernandez Barquin (Depto. CITIMAC, Universidad de Cantabria, Spain) , A. Yedra (Depto. CITIMAC, Universidad de Cantabria, Spain) , S. N. Kaul (School of Physics, University of Hyderabad, India) , M. L. Fdez-gubieda (Universidad País Vasco, Spain) , J. F. W. Mosselmans (Diamond Light Source) , Q. A. Pankhurst (UCL and London Centre for Nanotechnology, U.K.)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Non-crystalline Solids , VOL 353 , PAGES 733 - 737

State: Published (Approved)
Published: April 2007

Abstract: Core/shell nanoparticles of M–B (M = Fe, Co) with amorphous and mixed amorphous + bcc-Fe core have been synthesized by chemical reduction of metallic salts by sodium borohydride. The XANES spectra show the existence of a surface layer consisting of metallic hydroxides in a percentage around 15 at.%. The EXAFS reveals the existence of short-range order in the amorphous core with a contribution from the M–O pairs of the shell and a variation of the coordination numbers with respect to bulk alloys. The existence of Fe-bcc in the mixed alloys is observed in the Fourier transform of the EXAFS data.

Journal Keywords: Nanoparticles

Subject Areas: Chemistry, Materials

Facility: SRS