| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1528670 | Materials Science and Engineering: B | 2014 | 5 Pages |
•The La2O3-CaO composite additive for the Mg2Ni alloys is created.•Hydrogen kinetic properties of Mg2Ni alloys at low temperature are improved.•Hydrogen decomposing onset temperature of the composites is decreased to 470 K.
La2O3-CaO composite additive is employed to accelerate the hydrogen absorption/desorption rate of the Mg2Ni alloy. The composite additive was ball milled with Mg2Ni hydride to produce Mg2Ni–5 wt.% La2O3–5 wt.% CaO composite. The composite additive significantly reduces the thermal stability of Mg2NiH4. The onset decomposition temperature of the hydrogenated composite is 470 K, 21 K lower than that of the pure Mg2NiH4. Meanwhile, the composite presents accelerated hydriding/dehydriding kinetic properties. It absorbs 1.61 wt.% H at 373 K in 2 h and releases 2.44 wt.% H at 573 K in 1200 s, while the absorbed and desorbed hydrogen by the Mg2NiH4 is only 0.78 wt.% H and 1.32 wt.% H, respectively. The improvement in the hydrogen storage properties of the Mg2Ni alloy by the adoption of La2O3-CaO additive is ascribed to the modified catalytic effects of La2O3 and CaO in the composite.
