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Title: Effect of Precursor on the Electronic and Geometric Properties of Cobalt Nanoparticles Investigated by Co-K XANES and EXAFS

Abstract

By varying techniques and parameters in wet-chemical synthesis Co-nanoparticles different crystallographic structures (hcp, fcc and epsilon) can be synthesized. Co-K XANES and EXAFS spectra are very powerful tools to distinguish between those structures. In this study we are investigating for the first time the effect of the precursor molecule used for the synthesis on the electronic and geometric properties of cobalt nanoparticles. As precursors two organometallic cobalt complexes were used: alkyne-bridged dicobalthexacarbonyl [(Co2({mu}-HC{identical_to}CH)(CO)6] (ADH) and the well known dicobalt octacarbonyl [Co2(CO)8] (DCO). Both precursors were thermally decomposed under identical reaction conditions. Besides, effect of the precursor on the Co NPs was also investigated when two different types of surfactants are utilized in the reaction, oleic acid and n-trioctylphosphine. When only oleic acid was used as the surfactant, the XAFS analysis showed formation of fcc structure with ADH and hcp with DCO. When a combination of oleic acid and TOP were used, the crystal structure of CO NPs obtained is currently being analyzed.

Authors:
; ; ;  [1]
  1. Center for Advanced Microstructures and Devices (CAMD), Louisiana State University, 6980 Jefferson Hwy, Baton Rouge, LA 70806 (United States)
Publication Date:
OSTI Identifier:
21054738
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644655; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; CARBON DIOXIDE; CARBON MONOXIDE; COBALT; COBALT COMPLEXES; ELECTRONIC STRUCTURE; FCC LATTICES; FINE STRUCTURE; HCP LATTICES; NANOSTRUCTURES; OLEIC ACID; ORGANOMETALLIC COMPOUNDS; PARTICLE SIZE; PARTICLES; SURFACTANTS; SYNTHESIS; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Palshin, Vadim, Silva, Rohini M. de, Hormes, Josef, and Kumar, Challa S. S. R. Effect of Precursor on the Electronic and Geometric Properties of Cobalt Nanoparticles Investigated by Co-K XANES and EXAFS. United States: N. p., 2007. Web. doi:10.1063/1.2644655.
Palshin, Vadim, Silva, Rohini M. de, Hormes, Josef, & Kumar, Challa S. S. R. Effect of Precursor on the Electronic and Geometric Properties of Cobalt Nanoparticles Investigated by Co-K XANES and EXAFS. United States. doi:10.1063/1.2644655.
Palshin, Vadim, Silva, Rohini M. de, Hormes, Josef, and Kumar, Challa S. S. R. Fri . "Effect of Precursor on the Electronic and Geometric Properties of Cobalt Nanoparticles Investigated by Co-K XANES and EXAFS". United States. doi:10.1063/1.2644655.
@article{osti_21054738,
title = {Effect of Precursor on the Electronic and Geometric Properties of Cobalt Nanoparticles Investigated by Co-K XANES and EXAFS},
author = {Palshin, Vadim and Silva, Rohini M. de and Hormes, Josef and Kumar, Challa S. S. R.},
abstractNote = {By varying techniques and parameters in wet-chemical synthesis Co-nanoparticles different crystallographic structures (hcp, fcc and epsilon) can be synthesized. Co-K XANES and EXAFS spectra are very powerful tools to distinguish between those structures. In this study we are investigating for the first time the effect of the precursor molecule used for the synthesis on the electronic and geometric properties of cobalt nanoparticles. As precursors two organometallic cobalt complexes were used: alkyne-bridged dicobalthexacarbonyl [(Co2({mu}-HC{identical_to}CH)(CO)6] (ADH) and the well known dicobalt octacarbonyl [Co2(CO)8] (DCO). Both precursors were thermally decomposed under identical reaction conditions. Besides, effect of the precursor on the Co NPs was also investigated when two different types of surfactants are utilized in the reaction, oleic acid and n-trioctylphosphine. When only oleic acid was used as the surfactant, the XAFS analysis showed formation of fcc structure with ADH and hcp with DCO. When a combination of oleic acid and TOP were used, the crystal structure of CO NPs obtained is currently being analyzed.},
doi = {10.1063/1.2644655},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
  • No abstract prepared.
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