Effect of the nanometric LiFePO4 on the hydrogen storage properties of MgH2
| Autor: | Wei Zhang, Zhen Zhao, Jian Liu, Ying Cheng, Kai Cheng |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Materials science
Hydrogen Renewable Energy Sustainability and the Environment Composite number Inorganic chemistry Doping Energy Engineering and Power Technology chemistry.chemical_element 02 engineering and technology Activation energy 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Hydrothermal circulation 0104 chemical sciences Hydrogen storage Fuel Technology chemistry X-ray photoelectron spectroscopy Dehydrogenation 0210 nano-technology |
| Zdroj: | International Journal of Hydrogen Energy. 42:356-365 |
| ISSN: | 0360-3199 |
| Popis: | A nanometric phosphoric complex salt additive was synthesized by hydrothermal method. Its catalytic effect on the hydrogen storage properties of MgH 2 was investigated. MgH 2 +20 wt.% LiFePO 4 obtained by ball-milling process had an ability of absorbing 2.03 wt.% hydrogen at 423 K in 21 min, and only 0.98 wt.% could be absorbed by MgH 2 for the identical condition. 3.61 wt.% hydrogen could be released by the composite at 623 K in 21 min, whereas only 2.23 wt.% was desorbed by as-received MgH 2 . Doping by nanometric LiFePO 4 expressively enhanced the hydrogenation/dehydrogenation properties of MgH 2 , and changed the rate-controlling steps from three-dimensional interfacial reaction to one-dimensional diffusion process. Meanwhile, the onset dehydrogenation temperature for MgH 2 +20 wt.% LiFePO 4 was 653 K, which was found to be 60 K lower than the as-received MgH 2 . In addition, the addition of LiFePO 4 also lowered the activation energy ( E a) 31 kJ mol −1 . Based on XRD and XPS analysis, the in situ formed phases LiMgPO 4 and Fe, which are produced by the reaction between MgH 2 and LiFePO 4 , may be responsible for the remarkable improvement in hydrogen storage properties of MgH 2 . |
| Databáze: | OpenAIRE |
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