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Title: Stabilization of hexagonal close-packed metallic nickel for alumina-supported systems prepared from Ni(II) glycinate

Abstract

The decomposition in flowing argon of the neutral complex [Ni{sup II}(glycinate){sub 2}(H{sub 2}O){sub 2}] leads to a mixture of face-centered cubic (fcc) and hexagonal close-packed (hcp) metallic nickel. The latter is the main phase when the Ni(II) complex is supported on alumina. Unlike most hexagonal Ni phases described earlier, and similar to hexagonal Ni{sub 3}C, the unit cell parameters (a=0.2493 and c=0.4084nm) lead to Ni-Ni distances equal to those encountered in fcc Ni. TEM shows that the nanoparticles are protected by graphite layers, whose elimination by heating in hydrogen results in transformation to the fcc phase and crystal growth. Magnetic measurements provide evidence of the coexistence of superparamagnetic and ferromagnetic nanoparticles. This result is in line with the broad size distribution observed by TEM and is interpreted on the basis of the metallic character of hcp Ni particles.

Authors:
 [1];  [2];  [1];  [1];  [3];  [4]
  1. Laboratoire de Reactivite de Surface (UMR 7609 CNRS), Universite Pierre et Marie Curie-Paris 6, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
  2. Laboratoire de Reactivite de Surface (UMR 7609 CNRS), Universite Pierre et Marie Curie-Paris 6, 4 Place Jussieu, 75252 Paris Cedex 05 (France), E-mail: eric.marceau@upmc.fr
  3. (France)
  4. Laboratoire de Chimie Inorganique et Materiaux Moleculaires (UMR 7071 CNRS), Universite Pierre et Marie Curie-Paris 6, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
Publication Date:
OSTI Identifier:
21015614
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 1; Other Information: DOI: 10.1016/j.jssc.2006.09.015; PII: S0022-4596(06)00523-8; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ALUMINIUM OXIDES; ARGON; CRYSTAL GROWTH; DECOMPOSITION; ELECTRON DIFFRACTION; FCC LATTICES; GLYCINE; GRAPHITE; HCP LATTICES; HEATING; HYDROGEN; LAYERS; MIXTURES; NANOSTRUCTURES; NICKEL; NICKEL COMPLEXES; PARTICLES; STABILIZATION; SUPERPARAMAGNETISM; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Rodriguez-Gonzalez, Vicente, Marceau, Eric, Beaunier, Patricia, Che, Michel, Institut Universitaire de France, and Train, Cyrille. Stabilization of hexagonal close-packed metallic nickel for alumina-supported systems prepared from Ni(II) glycinate. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2006.09.015.
Rodriguez-Gonzalez, Vicente, Marceau, Eric, Beaunier, Patricia, Che, Michel, Institut Universitaire de France, & Train, Cyrille. Stabilization of hexagonal close-packed metallic nickel for alumina-supported systems prepared from Ni(II) glycinate. United States. doi:10.1016/j.jssc.2006.09.015.
Rodriguez-Gonzalez, Vicente, Marceau, Eric, Beaunier, Patricia, Che, Michel, Institut Universitaire de France, and Train, Cyrille. Mon . "Stabilization of hexagonal close-packed metallic nickel for alumina-supported systems prepared from Ni(II) glycinate". United States. doi:10.1016/j.jssc.2006.09.015.
@article{osti_21015614,
title = {Stabilization of hexagonal close-packed metallic nickel for alumina-supported systems prepared from Ni(II) glycinate},
author = {Rodriguez-Gonzalez, Vicente and Marceau, Eric and Beaunier, Patricia and Che, Michel and Institut Universitaire de France and Train, Cyrille},
abstractNote = {The decomposition in flowing argon of the neutral complex [Ni{sup II}(glycinate){sub 2}(H{sub 2}O){sub 2}] leads to a mixture of face-centered cubic (fcc) and hexagonal close-packed (hcp) metallic nickel. The latter is the main phase when the Ni(II) complex is supported on alumina. Unlike most hexagonal Ni phases described earlier, and similar to hexagonal Ni{sub 3}C, the unit cell parameters (a=0.2493 and c=0.4084nm) lead to Ni-Ni distances equal to those encountered in fcc Ni. TEM shows that the nanoparticles are protected by graphite layers, whose elimination by heating in hydrogen results in transformation to the fcc phase and crystal growth. Magnetic measurements provide evidence of the coexistence of superparamagnetic and ferromagnetic nanoparticles. This result is in line with the broad size distribution observed by TEM and is interpreted on the basis of the metallic character of hcp Ni particles.},
doi = {10.1016/j.jssc.2006.09.015},
journal = {Journal of Solid State Chemistry},
number = 1,
volume = 180,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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