Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control
© 2020 American Chemical Society. Metal hydrides continue to vie for attention as materials in multiple technological applications including hydrogen storage media, thermal energy storage (TES) materials, and hydrogen compressors. These applications depend on the temperature at which the materia...
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| Format: | Journal Article |
| Language: | English |
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AMER CHEMICAL SOC
2020
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| Online Access: | http://purl.org/au-research/grants/arc/DP150101708 http://hdl.handle.net/20.500.11937/82253 |
| _version_ | 1848764486091014144 |
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| author | Humphries, Terry Yang, J. Mole, R.A. Paskevicius, Mark Bird, Julianne Rowles, Matthew Tortoza, Mariana Sofianos, M. Veronica Yu, D. Buckley, Craig |
| author_facet | Humphries, Terry Yang, J. Mole, R.A. Paskevicius, Mark Bird, Julianne Rowles, Matthew Tortoza, Mariana Sofianos, M. Veronica Yu, D. Buckley, Craig |
| author_sort | Humphries, Terry |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | © 2020 American Chemical Society.
Metal hydrides continue to vie for attention as materials in multiple technological applications including hydrogen storage media, thermal energy storage (TES) materials, and hydrogen compressors. These applications depend on the temperature at which the materials desorb and reabsorb hydrogen. Magnesium hydride is ideal as a TES material, although its practical operating temperature is capped at ∼450 °C because of material degradation and high operating pressure. Fluorine substitution for hydrogen in magnesium hydride has previously been shown to increase the operating temperature of the metal hydride while limiting degradation, although full characterization is required before technological application can be ensured. The present study characterizes Mg(HxF1-x)2 solid solutions (x = 1, 0.95, 0.70, 0.85, 0.50, and 0) by inelastic neutron spectroscopy, powder X-ray diffraction, and thermal conductivity measurements, with the results being verified by density functional theory. For each experiment, a clear trend is observed throughout a series of solid solutions, showing the possibility of tuning the properties of MgH2. As F- substitution increases, the average Mg-H(F) bond distance elongates along the axial positions of the Mg-H(F) octahedra. Overall, this leads to an increase in Mg-H bond strength and thermal stability, improving the viability of Mg-H-F as potential TES materials. |
| first_indexed | 2025-11-14T11:20:07Z |
| format | Journal Article |
| id | curtin-20.500.11937-82253 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:20:07Z |
| publishDate | 2020 |
| publisher | AMER CHEMICAL SOC |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-822532021-04-15T07:14:51Z Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control Humphries, Terry Yang, J. Mole, R.A. Paskevicius, Mark Bird, Julianne Rowles, Matthew Tortoza, Mariana Sofianos, M. Veronica Yu, D. Buckley, Craig Science & Technology Physical Sciences Technology Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science THERMAL-CONDUCTIVITY VIBRATIONAL-SPECTRUM X-RAY HYDROGEN OPTIMIZATION SCATTERING HEAT MGH2 © 2020 American Chemical Society. Metal hydrides continue to vie for attention as materials in multiple technological applications including hydrogen storage media, thermal energy storage (TES) materials, and hydrogen compressors. These applications depend on the temperature at which the materials desorb and reabsorb hydrogen. Magnesium hydride is ideal as a TES material, although its practical operating temperature is capped at ∼450 °C because of material degradation and high operating pressure. Fluorine substitution for hydrogen in magnesium hydride has previously been shown to increase the operating temperature of the metal hydride while limiting degradation, although full characterization is required before technological application can be ensured. The present study characterizes Mg(HxF1-x)2 solid solutions (x = 1, 0.95, 0.70, 0.85, 0.50, and 0) by inelastic neutron spectroscopy, powder X-ray diffraction, and thermal conductivity measurements, with the results being verified by density functional theory. For each experiment, a clear trend is observed throughout a series of solid solutions, showing the possibility of tuning the properties of MgH2. As F- substitution increases, the average Mg-H(F) bond distance elongates along the axial positions of the Mg-H(F) octahedra. Overall, this leads to an increase in Mg-H bond strength and thermal stability, improving the viability of Mg-H-F as potential TES materials. 2020 Journal Article http://hdl.handle.net/20.500.11937/82253 10.1021/acs.jpcc.9b11211 English http://purl.org/au-research/grants/arc/DP150101708 http://purl.org/au-research/grants/arc/FT160100303 http://purl.org/au-research/grants/arc/LP120101848 http://purl.org/au-research/grants/arc/LP150100730 AMER CHEMICAL SOC fulltext |
| spellingShingle | Science & Technology Physical Sciences Technology Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science THERMAL-CONDUCTIVITY VIBRATIONAL-SPECTRUM X-RAY HYDROGEN OPTIMIZATION SCATTERING HEAT MGH2 Humphries, Terry Yang, J. Mole, R.A. Paskevicius, Mark Bird, Julianne Rowles, Matthew Tortoza, Mariana Sofianos, M. Veronica Yu, D. Buckley, Craig Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control |
| title | Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control |
| title_full | Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control |
| title_fullStr | Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control |
| title_full_unstemmed | Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control |
| title_short | Fluorine Substitution in Magnesium Hydride as a Tool for Thermodynamic Control |
| title_sort | fluorine substitution in magnesium hydride as a tool for thermodynamic control |
| topic | Science & Technology Physical Sciences Technology Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science THERMAL-CONDUCTIVITY VIBRATIONAL-SPECTRUM X-RAY HYDROGEN OPTIMIZATION SCATTERING HEAT MGH2 |
| url | http://purl.org/au-research/grants/arc/DP150101708 http://purl.org/au-research/grants/arc/DP150101708 http://purl.org/au-research/grants/arc/DP150101708 http://purl.org/au-research/grants/arc/DP150101708 http://hdl.handle.net/20.500.11937/82253 |