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Title: Hydrogen behavior in Mg+-implanted graphite

Abstract

A graphite wafer has been implanted with Mg+ to produce a uniform Mg concentration. Subsequent H+ implantation covered both the Mg+-implanted and unimplanted regions. Ion-beam analysis shows a higher H retention in graphite embedded with Mg than in regions without Mg. A small amount of H diffuses out of the H+ implanted graphite during thermal annealing at temperatures up to 300°C. However, significant H release from the region implanted with both Mg+ and H+ ions occurs at 150°C; further release is also observed at 300°C. The results suggest that there are efficient H trapping centers and fast pathways for H diffusion in the Mg+ implanted graphite, which may prove highly desirable for reversible H storage.implanted graphite, which may prove highly desirable for reversible H storage.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
881679
Report Number(s):
PNNL-SA-44188
Journal ID: ISSN 0884-2914; JMREEE; 3448; KC0201020; TRN: US200613%%67
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Materials Research, 21(4):811-815; Journal Volume: 21; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; ANNEALING; DIFFUSION; GRAPHITE; HYDROGEN; RETENTION; STORAGE; TRAPPING; Hydrogen; ion implantation; graphite; Environmental Molecular Sciences Laboratory

Citation Formats

Jiang, Weilin, Shutthanandan, V., Zhang, Yanwen, Thevuthasan, Suntharampillai, Weber, William J., and Exarhos, Gregory J.. Hydrogen behavior in Mg+-implanted graphite. United States: N. p., 2006. Web. doi:10.1557/jmr.2006.0121.
Jiang, Weilin, Shutthanandan, V., Zhang, Yanwen, Thevuthasan, Suntharampillai, Weber, William J., & Exarhos, Gregory J.. Hydrogen behavior in Mg+-implanted graphite. United States. doi:10.1557/jmr.2006.0121.
Jiang, Weilin, Shutthanandan, V., Zhang, Yanwen, Thevuthasan, Suntharampillai, Weber, William J., and Exarhos, Gregory J.. Sat . "Hydrogen behavior in Mg+-implanted graphite". United States. doi:10.1557/jmr.2006.0121.
@article{osti_881679,
title = {Hydrogen behavior in Mg+-implanted graphite},
author = {Jiang, Weilin and Shutthanandan, V. and Zhang, Yanwen and Thevuthasan, Suntharampillai and Weber, William J. and Exarhos, Gregory J.},
abstractNote = {A graphite wafer has been implanted with Mg+ to produce a uniform Mg concentration. Subsequent H+ implantation covered both the Mg+-implanted and unimplanted regions. Ion-beam analysis shows a higher H retention in graphite embedded with Mg than in regions without Mg. A small amount of H diffuses out of the H+ implanted graphite during thermal annealing at temperatures up to 300°C. However, significant H release from the region implanted with both Mg+ and H+ ions occurs at 150°C; further release is also observed at 300°C. The results suggest that there are efficient H trapping centers and fast pathways for H diffusion in the Mg+ implanted graphite, which may prove highly desirable for reversible H storage.implanted graphite, which may prove highly desirable for reversible H storage.},
doi = {10.1557/jmr.2006.0121},
journal = {Journal of Materials Research, 21(4):811-815},
number = 4,
volume = 21,
place = {United States},
year = {Sat Apr 01 00:00:00 EST 2006},
month = {Sat Apr 01 00:00:00 EST 2006}
}
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