Synthesis and characterization of nanocrystalline Mg sub(2)CoH sub(5) obtained by mechanical alloying
The stoichiometric mixture of 2MgH sub(2) + Co was ball milled under a hydrogen atmosphere to synthesize nanocrystalline metal hydride Mg sub(2)CoH sub(5). Upon milling, the mixture was analyzed by X-ray powder diffraction (XRD) and thermal methods employing the techniques of differential scanning c...
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Published in | Journal of materials science Vol. 36; no. 24; pp. 5829 - 5834 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
15.12.2001
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Online Access | Get full text |
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Summary: | The stoichiometric mixture of 2MgH sub(2) + Co was ball milled under a hydrogen atmosphere to synthesize nanocrystalline metal hydride Mg sub(2)CoH sub(5). Upon milling, the mixture was analyzed by X-ray powder diffraction (XRD) and thermal methods employing the techniques of differential scanning calorimetry (DSC), thermogravimetry (TG) and differential thermal analysis (DTA). Hydrogen absorption and desorption measured by pressure-composition-temperature (P-C-T) curves indicated that the capacity loss was small after 20 consecutive cycling tests. The enthalpies associated with hydride formation and decomposition were measured to be -69.5 and -83.2 kJ mol super(-1) H sub(2), respectively. At the temperatures of this study (553 to 653 K), hysteresis decreases with increasing temperature. copyright 2001 Kluwer Academic Publishers. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 content type line 23 ObjectType-Feature-1 |
ISSN: | 0022-2461 |