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Title: Metal-diboride nanotubes as high capacity hydrogen storage media

Abstract

We investigate the potential for hydrogen storage of a new class of nanomaterials, metal-diboride nanotubes. These materials have the merits of high density of binding sites on the tubular surfaces without the adverse effects of metal clustering. Using the TiB2 (8,0) and (5,5) nanotube as prototype examples, we show through first-principles calculations that each Ti atom can host two intact H2 units, leading to a retrievable hydrogen storage capacity of 5.5 wt%. Most strikingly, the binding energies fall in the desirable range of 0.2-0.6 eV per H2 molecule, endowing these structures with the potential for room temperature, near ambient pressure applications.

Authors:
 [1];  [2];  [1]
  1. ORNL
  2. Harvard University
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1000868
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters; Journal Volume: 7; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; ATOMS; CAPACITY; HYDROGEN STORAGE; NANOTUBES

Citation Formats

Meng, Sheng, Kaxiras, Efthimios, and Zhang, Zhenyu. Metal-diboride nanotubes as high capacity hydrogen storage media. United States: N. p., 2007. Web. doi:10.1021/nl062692g.
Meng, Sheng, Kaxiras, Efthimios, & Zhang, Zhenyu. Metal-diboride nanotubes as high capacity hydrogen storage media. United States. doi:10.1021/nl062692g.
Meng, Sheng, Kaxiras, Efthimios, and Zhang, Zhenyu. Mon . "Metal-diboride nanotubes as high capacity hydrogen storage media". United States. doi:10.1021/nl062692g.
@article{osti_1000868,
title = {Metal-diboride nanotubes as high capacity hydrogen storage media},
author = {Meng, Sheng and Kaxiras, Efthimios and Zhang, Zhenyu},
abstractNote = {We investigate the potential for hydrogen storage of a new class of nanomaterials, metal-diboride nanotubes. These materials have the merits of high density of binding sites on the tubular surfaces without the adverse effects of metal clustering. Using the TiB2 (8,0) and (5,5) nanotube as prototype examples, we show through first-principles calculations that each Ti atom can host two intact H2 units, leading to a retrievable hydrogen storage capacity of 5.5 wt%. Most strikingly, the binding energies fall in the desirable range of 0.2-0.6 eV per H2 molecule, endowing these structures with the potential for room temperature, near ambient pressure applications.},
doi = {10.1021/nl062692g},
journal = {Nano Letters},
number = 3,
volume = 7,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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