Back to Search
Start Over
The Importance of Rare-Earth Additions in Zr-Based AB2 Metal Hydride Alloys
- Source :
- Batteries; Volume 2; Issue 3; Pages: 25, Batteries, Vol 2, Iss 3, p 25 (2016)
- Publication Year :
- 2016
- Publisher :
- Multidisciplinary Digital Publishing Institute, 2016.
-
Abstract
- Effects of substitutions of rare earth (RE) elements (Y, La, Ce, and Nd) to the Zr-based AB2 multi-phase metal hydride (MH) alloys on the structure, gaseous phase hydrogen storage (H-storage), and electrochemical properties were studied and compared. Solubilities of the RE atoms in the main Laves phases (C14 and C15) are very low, and therefore the main contributions of the RE additives are through the formation of the RENi phase and change in TiNi phase abundance. Both the RENi and TiNi phases are found to facilitate the bulk diffusion of hydrogen but impede the surface reaction. The former is very effective in improving the activation behaviors. −40 °C performances of the Ce-doped alloys are slightly better than the Nd-doped alloys but not as good as those of the La-doped alloys, which gained the improvement through a different mechanism. While the improvement in ultra-low-temperature performance of the Ce-containing alloys can be associated with a larger amount of metallic Ni-clusters embedded in the surface oxide, the improvement in the La-containing alloys originates from the clean alloy/oxide interface as shown in an earlier transmission electron microscopy study. Overall, the substitution of 1 at% Ce to partially replace Zr gives the best electrochemical performances (capacity, rate, and activation) and is recommended for all the AB2 MH alloys for electrochemical applications.
- Subjects :
- Materials science
Hydrogen
Laves phase alloy
Alloy
Inorganic chemistry
Oxide
Energy Engineering and Power Technology
chemistry.chemical_element
02 engineering and technology
engineering.material
rare earth (RE) element
010402 general chemistry
Electrochemistry
01 natural sciences
Metal
Hydrogen storage
chemistry.chemical_compound
Phase (matter)
lcsh:TK1001-1841
Electrical and Electronic Engineering
metal hydride (MH)
nickel/metal hydride (Ni/MH) battery
electrochemistry
pressure concentration isotherm
Hydride
021001 nanoscience & nanotechnology
0104 chemical sciences
lcsh:Production of electric energy or power. Powerplants. Central stations
chemistry
lcsh:Industrial electrochemistry
visual_art
visual_art.visual_art_medium
engineering
0210 nano-technology
lcsh:TP250-261
Subjects
Details
- Language :
- English
- ISSN :
- 23130105
- Database :
- OpenAIRE
- Journal :
- Batteries; Volume 2; Issue 3; Pages: 25
- Accession number :
- edsair.doi.dedup.....7ca2dd93ca3de7f58c1699999d242907
- Full Text :
- https://doi.org/10.3390/batteries2030025