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Title: Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption

Abstract

Structural analysis of high Deuterium absorbed 5 nm Pd particles in dispersed ZrO2 has been carried out using XAFS techniques. X-ray absorption spectra around the Pd K-absorption edge were observed and analyzed. The Pd-Pd bonding distance in the fcc Pd lattice was enlarged by 0.08 {approx} 0.09 A during absorption of deuterium, and it completely reverted to its original state with the release of deuterium while maintaining the crystal lattice symmetry. These changes provide evidence that deuterium locates not on the surface of the Pd particle, but rather within the Pd crystal lattice. XANES spectra clearly indicate that any change in the oxidation state of Pd are not observed, resulting in no reaction of the absorbed Deuterium atoms with Pd atoms. This paper reports the alternation of Pd lattice in nano-sized composite during hydrogen absorption. The possible models of deuterium position in the Pd lattice are also discussed.

Authors:
;  [1]; ; ;  [2]; ;  [3];  [4]
  1. Faculty of Engineering, Kansai University, Suita, Osaka 564-8577, (Japan)
  2. ISIR, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, (Japan)
  3. Institute for Materials Research, Tohoku University, Sendai, Miyagi 980-8577, (Japan)
  4. Academician, Center for Advanced Science and Innovation, Osaka University, Suita, Osaka 567-0871, (Japan)
Publication Date:
OSTI Identifier:
21054733
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: 10.1063/1.2644649; (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 SPECTROSCOPY; ADSORPTION; COMPOSITE MATERIALS; CRYSTALS; DEUTERIUM; FCC LATTICES; FINE STRUCTURE; HYDROGEN; INTERFACES; K ABSORPTION; NANOSTRUCTURES; PALLADIUM; PARTICLES; SURFACES; SYMMETRY; VALENCE; X-RAY SPECTRA; X-RAY SPECTROSCOPY; ZIRCONIUM OXIDES

Citation Formats

Arachi, Yoshinori, Asai, Takeshi, Emura, Shuichi, Omura, Akira, Nunogaki, Masanobu, Yamaura, Shunichi, Inoue, Akihisa, and Arata, Yoshiaki. Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption. United States: N. p., 2007. Web. doi:10.1063/1.2644649.
Arachi, Yoshinori, Asai, Takeshi, Emura, Shuichi, Omura, Akira, Nunogaki, Masanobu, Yamaura, Shunichi, Inoue, Akihisa, & Arata, Yoshiaki. Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption. United States. doi:10.1063/1.2644649.
Arachi, Yoshinori, Asai, Takeshi, Emura, Shuichi, Omura, Akira, Nunogaki, Masanobu, Yamaura, Shunichi, Inoue, Akihisa, and Arata, Yoshiaki. Fri . "Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption". United States. doi:10.1063/1.2644649.
@article{osti_21054733,
title = {Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption},
author = {Arachi, Yoshinori and Asai, Takeshi and Emura, Shuichi and Omura, Akira and Nunogaki, Masanobu and Yamaura, Shunichi and Inoue, Akihisa and Arata, Yoshiaki},
abstractNote = {Structural analysis of high Deuterium absorbed 5 nm Pd particles in dispersed ZrO2 has been carried out using XAFS techniques. X-ray absorption spectra around the Pd K-absorption edge were observed and analyzed. The Pd-Pd bonding distance in the fcc Pd lattice was enlarged by 0.08 {approx} 0.09 A during absorption of deuterium, and it completely reverted to its original state with the release of deuterium while maintaining the crystal lattice symmetry. These changes provide evidence that deuterium locates not on the surface of the Pd particle, but rather within the Pd crystal lattice. XANES spectra clearly indicate that any change in the oxidation state of Pd are not observed, resulting in no reaction of the absorbed Deuterium atoms with Pd atoms. This paper reports the alternation of Pd lattice in nano-sized composite during hydrogen absorption. The possible models of deuterium position in the Pd lattice are also discussed.},
doi = {10.1063/1.2644649},
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}
}
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