Particle size and catalytic effect on the dehydriding of MgH2

D. Fátay, A. Révész, T. Spassov

Research output: Contribution to journalArticle

85 Citations (Scopus)

Abstract

Conventional polycrystalline β-MgH2 was ball-milled under hydrogen-atmosphere to reach a nanocrystalline microstructure (∼10 nm), until the particle- and grain-size attained a constant value. Subsequently, 2 mol.% pre-milled Nb2O5 (∼40 nm) was added to the MgH2 as a catalyst and the milling was continued. The effect of the particle- and grain-size as well as of the milling duration on the temperature of hydrogen desorption and on the dehydriding kinetics of the ball-milled MgH2 + Nb2O5 powders was analyzed. The grain- and particle-size reduction decreases substantially the H-desorption temperature. The size-reduction occurs during the first 120 min of milling MgH2, but subsequent milling with the catalyst results in additional slight MgH2 particle size decrease, due to the harder Nb 2O5 particles compared to the MgH2 ones. The decrease of the activation energy of dehydriding caused by the catalyst was observed after only 15 min of ball-milling. The catalytic effect is, however, suppressed at longer milling times, probably due to penetration of the catalytic particles into the MgH2.

Original languageEnglish
Pages (from-to)237-241
Number of pages5
JournalJournal of Alloys and Compounds
Volume399
Issue number1-2
DOIs
Publication statusPublished - Aug 16 2005

Fingerprint

Particle size
Catalysts
Hydrogen
Desorption
Ball milling
Powders
Activation energy
Temperature
Microstructure
Kinetics

Keywords

  • Ball-milling
  • Nanostructure
  • X-ray diffraction

ASJC Scopus subject areas

  • Metals and Alloys

Cite this

Particle size and catalytic effect on the dehydriding of MgH2. / Fátay, D.; Révész, A.; Spassov, T.

In: Journal of Alloys and Compounds, Vol. 399, No. 1-2, 16.08.2005, p. 237-241.

Research output: Contribution to journalArticle

Fátay, D. ; Révész, A. ; Spassov, T. / Particle size and catalytic effect on the dehydriding of MgH2. In: Journal of Alloys and Compounds. 2005 ; Vol. 399, No. 1-2. pp. 237-241.
@article{08accb7e87ce4c35aec6a6f4aa532c8c,
title = "Particle size and catalytic effect on the dehydriding of MgH2",
abstract = "Conventional polycrystalline β-MgH2 was ball-milled under hydrogen-atmosphere to reach a nanocrystalline microstructure (∼10 nm), until the particle- and grain-size attained a constant value. Subsequently, 2 mol.{\%} pre-milled Nb2O5 (∼40 nm) was added to the MgH2 as a catalyst and the milling was continued. The effect of the particle- and grain-size as well as of the milling duration on the temperature of hydrogen desorption and on the dehydriding kinetics of the ball-milled MgH2 + Nb2O5 powders was analyzed. The grain- and particle-size reduction decreases substantially the H-desorption temperature. The size-reduction occurs during the first 120 min of milling MgH2, but subsequent milling with the catalyst results in additional slight MgH2 particle size decrease, due to the harder Nb 2O5 particles compared to the MgH2 ones. The decrease of the activation energy of dehydriding caused by the catalyst was observed after only 15 min of ball-milling. The catalytic effect is, however, suppressed at longer milling times, probably due to penetration of the catalytic particles into the MgH2.",
keywords = "Ball-milling, Nanostructure, X-ray diffraction",
author = "D. F{\'a}tay and A. R{\'e}v{\'e}sz and T. Spassov",
year = "2005",
month = "8",
day = "16",
doi = "10.1016/j.jallcom.2005.02.043",
language = "English",
volume = "399",
pages = "237--241",
journal = "Journal of Alloys and Compounds",
issn = "0925-8388",
publisher = "Elsevier BV",
number = "1-2",

}

TY - JOUR

T1 - Particle size and catalytic effect on the dehydriding of MgH2

AU - Fátay, D.

AU - Révész, A.

AU - Spassov, T.

PY - 2005/8/16

Y1 - 2005/8/16

N2 - Conventional polycrystalline β-MgH2 was ball-milled under hydrogen-atmosphere to reach a nanocrystalline microstructure (∼10 nm), until the particle- and grain-size attained a constant value. Subsequently, 2 mol.% pre-milled Nb2O5 (∼40 nm) was added to the MgH2 as a catalyst and the milling was continued. The effect of the particle- and grain-size as well as of the milling duration on the temperature of hydrogen desorption and on the dehydriding kinetics of the ball-milled MgH2 + Nb2O5 powders was analyzed. The grain- and particle-size reduction decreases substantially the H-desorption temperature. The size-reduction occurs during the first 120 min of milling MgH2, but subsequent milling with the catalyst results in additional slight MgH2 particle size decrease, due to the harder Nb 2O5 particles compared to the MgH2 ones. The decrease of the activation energy of dehydriding caused by the catalyst was observed after only 15 min of ball-milling. The catalytic effect is, however, suppressed at longer milling times, probably due to penetration of the catalytic particles into the MgH2.

AB - Conventional polycrystalline β-MgH2 was ball-milled under hydrogen-atmosphere to reach a nanocrystalline microstructure (∼10 nm), until the particle- and grain-size attained a constant value. Subsequently, 2 mol.% pre-milled Nb2O5 (∼40 nm) was added to the MgH2 as a catalyst and the milling was continued. The effect of the particle- and grain-size as well as of the milling duration on the temperature of hydrogen desorption and on the dehydriding kinetics of the ball-milled MgH2 + Nb2O5 powders was analyzed. The grain- and particle-size reduction decreases substantially the H-desorption temperature. The size-reduction occurs during the first 120 min of milling MgH2, but subsequent milling with the catalyst results in additional slight MgH2 particle size decrease, due to the harder Nb 2O5 particles compared to the MgH2 ones. The decrease of the activation energy of dehydriding caused by the catalyst was observed after only 15 min of ball-milling. The catalytic effect is, however, suppressed at longer milling times, probably due to penetration of the catalytic particles into the MgH2.

KW - Ball-milling

KW - Nanostructure

KW - X-ray diffraction

UR - http://www.scopus.com/inward/record.url?scp=21344444325&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=21344444325&partnerID=8YFLogxK

U2 - 10.1016/j.jallcom.2005.02.043

DO - 10.1016/j.jallcom.2005.02.043

M3 - Article

AN - SCOPUS:21344444325

VL - 399

SP - 237

EP - 241

JO - Journal of Alloys and Compounds

JF - Journal of Alloys and Compounds

SN - 0925-8388

IS - 1-2

ER -