Effect of Ti–Al substitution on the electrochemical properties of amorphous MgNi-based secondary hydride electrodes
| Autor: | Yijing Wang, Jiansheng Cao, Huatang Yuan, Jing-Wang Liu |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Materials science
Scanning electron microscope Mechanical Engineering Alloy Metals and Alloys Electrolyte engineering.material Dielectric spectroscopy Amorphous solid Crystallography Nickel–metal hydride battery Chemical engineering X-ray photoelectron spectroscopy Mechanics of Materials Electrode Materials Chemistry engineering |
| Zdroj: | Journal of Alloys and Compounds. 392:300-305 |
| ISSN: | 0925-8388 |
| Popis: | A new amorphous Mg0.7Ti0.225Al0.075Ni alloy was prepared by means of mechanical alloying (MA), its discharge capacity reached 218.32 mAh g−1 after 50 cycles, which retains 63.57% of the initial capacity of 343.44 mAh g−1. On the surface of the alloy during cycling in the electrolyte of 5 M KOH, the X-ray photoelectron spectroscopy (XPS) shows that the majority of magnesium and aluminum in the alloy exist in metallic state; Ti exists in the +3 oxidation state. Electrochemical impedance spectroscopy (EIS) shows that the aluminum lowered the charge transfer resistance. The structure of the alloy was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). And the improvement of cycle life of the electrode can be related to the formation of MgTi2O4. A study on the anti-corrosion properties in alkaline solution of the alloy electrode has been done, and it is shown that Ti and Al substitution of Mg improves the anti-corrosion properties significantly. It is found that Ti and Al substitution of Mg could improve the electrochemical behavior of MgNi-based electrodes. |
| Databáze: | OpenAIRE |
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