Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1606352 | Journal of Alloys and Compounds | 2016 | 43 Pages |
Abstract
Multi-wall carbon nanotubes supported nano-nickel (Ni/MWCNTs) with superior catalytic effects was introduced to magnesium hydride by the process of hydriding combustion synthesis (HCS) and mechanical milling (MM). The effect of different Ni/MWCNTs contents (5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%) on the hydrogenation and dehydrogenation properties of the composite was investigated systematically. It is revealed that Mg85-(Ni/MWCNTs)15 composite shows the best comprehensive hydrogen storage properties, which absorbs 5.68 wt.% hydrogen within 100 s at 373 K and releases 4.31 wt.% hydrogen within 1800 s at 523 K under initial hydrogen pressures of 3.0 and 0.005 MPa, respectively. The in situ formed nano-Mg2Ni and MWCNTs have excellent catalytic effect on the hydrogenation and dehydrogenation performances of MgH2. To further improve the hydrogen absorption/desorption properties, TiF3 was added to the Mg-Ni/MWCNTs system. The result shows that TiF3 addition has little influence on the thermodynamic performance, but affects greatly the kinetic properties. The Mg85-(Ni/MWCNTs)15-TiF3 composite exhibits an appreciably enhanced hydrogen desorption performance at low temperature, and the hydrogen desorption capacity within 1800 s at 473 K for the TiF3-added composite is approximately four times the capacity of Mg85-(Ni/MWCNTs)15 under the same condition. The catalytic effects during hydrogenation and dehydrogenation have been discussed in the study.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Wei Su, Yunfeng Zhu, Jiguang Zhang, Yana Liu, Yang Yang, Qifeng Mao, Liquan Li,