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Title: Size and structure of nanoparticles formed via ultraviolet photolysis of ferrocene

Abstract

Iron nanoparticles enclosed in carbon shells were formed by laser-assisted chemical vapor decomposition of ferrocene (Fe(C{sub 5}H{sub 5}){sub 2}) vapor in Ar gas atmosphere. The particle size dependence on the total ambient gas pressure and on laser fluence of the pulsed ArF excimer laser was examined and, e.g., an effective size decrease of the iron core was observed at elevated laser fluences. Characterizations of the iron and carbon microstructures were performed by x-ray diffraction and transmission electron microscopy, while relative iron deposition rates were measured by x-ray fluorescence spectroscopy. Both {alpha}-Fe and {gamma}-Fe phases were found for the single crystalline iron cores, surrounded by graphitic (inner) and amorphous (outer) carbon layers. The temperature rise of the laser-excited particles was also determined by optical spectroscopy of the emitted thermal radiation, which allowed an estimation of the iron loss of the nanoparticles due to evaporation. The estimated and measured iron losses are in good agreement.

Authors:
; ; ; ;  [1];  [2];  [3];  [4]
  1. Department of Applied Environmental Science, Stockholm University, Frescativaegen 50, SE-10691 Stockholm (Sweden)
  2. (Austria)
  3. (Sweden)
  4. (Hungary)
Publication Date:
OSTI Identifier:
20982681
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 3; Other Information: DOI: 10.1063/1.2432406; (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; BLACKBODY RADIATION; CHEMICAL VAPOR DEPOSITION; CRYSTAL STRUCTURE; EVAPORATION; EXCIMER LASERS; FERROCENE; GRAPHITE; IRON-ALPHA; IRON-GAMMA; MICROSTRUCTURE; MONOCRYSTALS; NANOSTRUCTURES; PARTICLE SIZE; PARTICLES; PHOTOLYSIS; THERMAL RADIATION; TRANSMISSION ELECTRON MICROSCOPY; ULTRAVIOLET RADIATION; X-RAY DIFFRACTION; X-RAY FLUORESCENCE ANALYSIS

Citation Formats

Elihn, K., Landstroem, L., Alm, O., Boman, M., Heszler, P., Institut fuer Angewandte Physik, Johannes-Kepler-Universitaet Linz, A-4040, Linz, The Angstroem Laboratory, Department of Materials Chemistry, Uppsala University, Box 538, SE-751 21 Uppsala, and Research Group on Laser Physics of the Hungarian Academy of Sciences, Szeged, Box 406, H-6721. Size and structure of nanoparticles formed via ultraviolet photolysis of ferrocene. United States: N. p., 2007. Web. doi:10.1063/1.2432406.
Elihn, K., Landstroem, L., Alm, O., Boman, M., Heszler, P., Institut fuer Angewandte Physik, Johannes-Kepler-Universitaet Linz, A-4040, Linz, The Angstroem Laboratory, Department of Materials Chemistry, Uppsala University, Box 538, SE-751 21 Uppsala, & Research Group on Laser Physics of the Hungarian Academy of Sciences, Szeged, Box 406, H-6721. Size and structure of nanoparticles formed via ultraviolet photolysis of ferrocene. United States. doi:10.1063/1.2432406.
Elihn, K., Landstroem, L., Alm, O., Boman, M., Heszler, P., Institut fuer Angewandte Physik, Johannes-Kepler-Universitaet Linz, A-4040, Linz, The Angstroem Laboratory, Department of Materials Chemistry, Uppsala University, Box 538, SE-751 21 Uppsala, and Research Group on Laser Physics of the Hungarian Academy of Sciences, Szeged, Box 406, H-6721. Thu . "Size and structure of nanoparticles formed via ultraviolet photolysis of ferrocene". United States. doi:10.1063/1.2432406.
@article{osti_20982681,
title = {Size and structure of nanoparticles formed via ultraviolet photolysis of ferrocene},
author = {Elihn, K. and Landstroem, L. and Alm, O. and Boman, M. and Heszler, P. and Institut fuer Angewandte Physik, Johannes-Kepler-Universitaet Linz, A-4040, Linz and The Angstroem Laboratory, Department of Materials Chemistry, Uppsala University, Box 538, SE-751 21 Uppsala and Research Group on Laser Physics of the Hungarian Academy of Sciences, Szeged, Box 406, H-6721},
abstractNote = {Iron nanoparticles enclosed in carbon shells were formed by laser-assisted chemical vapor decomposition of ferrocene (Fe(C{sub 5}H{sub 5}){sub 2}) vapor in Ar gas atmosphere. The particle size dependence on the total ambient gas pressure and on laser fluence of the pulsed ArF excimer laser was examined and, e.g., an effective size decrease of the iron core was observed at elevated laser fluences. Characterizations of the iron and carbon microstructures were performed by x-ray diffraction and transmission electron microscopy, while relative iron deposition rates were measured by x-ray fluorescence spectroscopy. Both {alpha}-Fe and {gamma}-Fe phases were found for the single crystalline iron cores, surrounded by graphitic (inner) and amorphous (outer) carbon layers. The temperature rise of the laser-excited particles was also determined by optical spectroscopy of the emitted thermal radiation, which allowed an estimation of the iron loss of the nanoparticles due to evaporation. The estimated and measured iron losses are in good agreement.},
doi = {10.1063/1.2432406},
journal = {Journal of Applied Physics},
number = 3,
volume = 101,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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