Design Strategies for Anode of Mg-Air Batteries and Hydrogen Evolution Reactions on Mg-RE Alloys

• Published in: ECS transactions Vol. 85; no. 13; pp. 95 - 107
• Main Authors: Shrestha, Nikunja, Zillinger, James, Utgikar, Vivek, Raja, Krishnan S.
• Format: Journal Article
• Language: English
• Published: The Electrochemical Society, Inc 19.06.2018
• ISSN: 1938-5862; 1938-6737; 1938-6737; 1938-5862
• DOI: 10.1149/08513.0095ecst

Commercial purity Mg, Mg-RE alloys ZE10A (UNS M11600), and EV31A (UNS M12310) were evaluated in the as-received condition for potential application as anode for Mg-air battery. Anodic and cathodic polarization studies were performed in 0.6 M NaCl, 0.5 M NaNO3 and 0.1 M Na2SO4 electrolytes. Hydrogen evolved during anodic polarization was measured at different potentials. Electrochemical impedance spectroscopy was carried out at open circuit conditions. The results showed that commercial purity magnesium had higher corrosion resistance than the Mg-RE alloy specimens in all the electrolytes tested. All the specimens showed negative difference effect (NDE) where the rate of hydrogen evolution increased with increased anodic polarization. The NDE was more pronounced on ZE10A than on other materials. The rate of hydrogen evolution was about three times higher in NaCl solution than in other two solutions. The results suggest that ZE10A could be a potential anode material for Mg-air battery due to its high anodic activity in spite of the observed NDE.