In the present work, a high electronegativity element substitution strategy was employed to obtain a better corrosion resistance and cycling performance of Ce 2 Ni 7 -type La 0.83−x Y x Mg 0.17 Ni 3.1 Co 0.3 Al 0.1 (x = 0.0-0.6) alloys. The abundance of the Ce 2 Ni 7 -type phase increased as x increased from 0 to 0.2 but it decreased with a further increase in x up to 0.6. The alloy with x = 0.2 further showed a superior discharge capacity (400.6 mA h g −1 ) and high cycling stability (S 320 = 75%). We found that the Y (electronegativity value χ Y = 1.22 > χ La = 1.10) element could play an essential role in enhancing the anti-corrosion of alloys based on a theoretical framework of the electronegativity of rare earth elements, thus leading to an excellent cycle lifetime of the alloys. The new alloying designs are expected to provide viable La-Mg-Ni-based intermetallic compounds as anode materials for commercial Ni-MH batteries.
All Science Journal Classification (ASJC) codes
- Inorganic Chemistry