Role of catalysts in dehydrogenation of MgH2 nanoclusters

被引：93

作者：

Larsson, Peter ^{[1
]}

Araujo, C. Moyses ^{[1
]}

Larsson, J. Andrea ^{[2
]}

Jena, Puru ^{[3
]}

Ahuja, Rajeev ^{[1
]}

机构：

[1] Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, S-75120 Uppsala, Sweden

[2] Natl Univ Ireland Univ Coll Cork, Tyndall Natl Inst, Cork, Ireland

[3] Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 2008年 / 105卷 / 24期

关键词：

hydrogen storage; transition metals; diffusion; catalysis;

D O I：

10.1073/pnas.0711743105

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

A fundamental understanding of the role of catalysts in dehydrogenation of MgH2 nanoclusters is provided by carrying out first-principles calculations based on density functional theory. It is shown that the transition metal atoms Ti, V, Fe, and Ni not only lower desorption energies significantly but also continue to attract at least four hydrogen atoms even when the total hydrogen content of the cluster decreases. In particular, Fe is found to migrate from the surface sites to the interior sites during the dehydrogenation process, releasing more hydrogen as it diffuses This diffusion mechanism may account for the fact that a small amount of catalysts is sufficient to improve the kinetics of MgH2. which is essential for the use of this material for hydrogen storage in fuel-cell applications.

引用

页码：8227 / 8231

页数：5

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