High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon
The thermochemical energy storage properties of calcium hydride (CaH2) destabilised with either silicon (Si) or CaxSiy compounds at various molar ratios, were thoroughly studied by a combination of experimental and computer assisted thermodynamic calculations. Particularly, the destabilisation effec...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
| Language: | English |
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ELSEVIER SCIENCE SA
2021
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| Online Access: | http://purl.org/au-research/grants/arc/LP150100730 http://hdl.handle.net/20.500.11937/90900 |
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| author | Griffond, Arnaud C.M. Sofianos, M. Veronica Sheppard, Drew Humphries, Terry Sargent, A.L. Dornheim, M. Aguey-Zinsou, K.F. Buckley, Craig |
| author_facet | Griffond, Arnaud C.M. Sofianos, M. Veronica Sheppard, Drew Humphries, Terry Sargent, A.L. Dornheim, M. Aguey-Zinsou, K.F. Buckley, Craig |
| author_sort | Griffond, Arnaud C.M. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The thermochemical energy storage properties of calcium hydride (CaH2) destabilised with either silicon (Si) or CaxSiy compounds at various molar ratios, were thoroughly studied by a combination of experimental and computer assisted thermodynamic calculations. Particularly, the destabilisation effect of Si on CaH2 at five different molar ratios (1:1, 1:2, 2:1, 3:4, 5:3 CaH2 to Si) was extensively investigated. Theoretical calculations predicted a multi-step thermal decomposition reaction between CaH2 and Si forming CaxSiy at varying temperatures, which was confirmed by in-situ synchrotron X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis and mass-spectroscopic measurements. The most suitable destabilisation reactions between CaH2 and Si or CaxSiy that meet the criteria of a thermal energy storage system for the next-generation of concentrated solar power (CSP) plants were identified. The CaH2 and CaSi system (in a 2:3 molar ratio of CaH2 to CaSi) showed desirable operating conditions with a decomposition temperature of 747 ± 33 °C at a hydrogen pressure of 1 bar. Pressure composition isothermal measurements were conducted on this system to determine its practical enthalpy of decomposition to form Ca5Si3. The calculated value (107.3 kJ mol−1 H2) was lower compared to the experimentally determined value (154 ± 4 kJ mol−1 H2). This mismatch was mainly due to the formation of CaO and a CaSi solid solution in addition to the desired Ca5Si3 phase. |
| first_indexed | 2025-11-14T11:35:31Z |
| format | Journal Article |
| id | curtin-20.500.11937-90900 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:35:31Z |
| publishDate | 2021 |
| publisher | ELSEVIER SCIENCE SA |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-909002023-05-07T23:57:10Z High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon Griffond, Arnaud C.M. Sofianos, M. Veronica Sheppard, Drew Humphries, Terry Sargent, A.L. Dornheim, M. Aguey-Zinsou, K.F. Buckley, Craig Science & Technology Physical Sciences Technology Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metal hydride Thermal energy storage Calcium hydride Thermodynamics Destabilisation The thermochemical energy storage properties of calcium hydride (CaH2) destabilised with either silicon (Si) or CaxSiy compounds at various molar ratios, were thoroughly studied by a combination of experimental and computer assisted thermodynamic calculations. Particularly, the destabilisation effect of Si on CaH2 at five different molar ratios (1:1, 1:2, 2:1, 3:4, 5:3 CaH2 to Si) was extensively investigated. Theoretical calculations predicted a multi-step thermal decomposition reaction between CaH2 and Si forming CaxSiy at varying temperatures, which was confirmed by in-situ synchrotron X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis and mass-spectroscopic measurements. The most suitable destabilisation reactions between CaH2 and Si or CaxSiy that meet the criteria of a thermal energy storage system for the next-generation of concentrated solar power (CSP) plants were identified. The CaH2 and CaSi system (in a 2:3 molar ratio of CaH2 to CaSi) showed desirable operating conditions with a decomposition temperature of 747 ± 33 °C at a hydrogen pressure of 1 bar. Pressure composition isothermal measurements were conducted on this system to determine its practical enthalpy of decomposition to form Ca5Si3. The calculated value (107.3 kJ mol−1 H2) was lower compared to the experimentally determined value (154 ± 4 kJ mol−1 H2). This mismatch was mainly due to the formation of CaO and a CaSi solid solution in addition to the desired Ca5Si3 phase. 2021 Journal Article http://hdl.handle.net/20.500.11937/90900 10.1016/j.jallcom.2020.158229 English http://purl.org/au-research/grants/arc/LP150100730 http://creativecommons.org/licenses/by/4.0/ ELSEVIER SCIENCE SA fulltext |
| spellingShingle | Science & Technology Physical Sciences Technology Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metal hydride Thermal energy storage Calcium hydride Thermodynamics Destabilisation Griffond, Arnaud C.M. Sofianos, M. Veronica Sheppard, Drew Humphries, Terry Sargent, A.L. Dornheim, M. Aguey-Zinsou, K.F. Buckley, Craig High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon |
| title | High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon |
| title_full | High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon |
| title_fullStr | High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon |
| title_full_unstemmed | High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon |
| title_short | High-temperature thermochemical energy storage using metal hydrides: Destabilisation of calcium hydride with silicon |
| title_sort | high-temperature thermochemical energy storage using metal hydrides: destabilisation of calcium hydride with silicon |
| topic | Science & Technology Physical Sciences Technology Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metal hydride Thermal energy storage Calcium hydride Thermodynamics Destabilisation |
| url | http://purl.org/au-research/grants/arc/LP150100730 http://hdl.handle.net/20.500.11937/90900 |