Corrosion of Hydrogen Storage Metal Alloy LaMm-Ni4.1Al0.3Mn0.4Co0.45 in the Aqueous Solutions of Alkali Metal Hydroxides

Materials

KarolJ. Fijalkowski¹  Malgorzata Karwowska²  AndrzejA. Czerwiński² 

[1] Centre of New Technologies, University of Warsaw, ul. Banacha 2c, 02-097 Warsaw, Poland;Faculty of Chemistry, University of Warsaw, ul. Pasteura 1, 02-093 Warsaw, Poland;

关键词: Ni-MH battery;    AB₅ alloy;    hydrogen sorption;    corrosion;    limited volume electrode (LVE);   

DOI  :  10.3390/ma11122423

来源: DOAJ

【 摘 要 】

Corrosion of pristine AB₅-type metal alloy LaMm-Ni_4.1Al_0.3Mn_0.4Co_0.45 in the aqueous solutions of alkali metal hydroxides of diverse composition and concentration was tested. Correlation was observed between the alloy corrosion intensity in various hydroxide solutions, and its electrochemical capacity in these electrolytes. Mm(OH)₃, CoO(OH), and nickel metal aggregates were detected among the products of selective oxidation of the alloy. High intensity corrosion of the alloy was observed in RbOH and CsOH solutions leading to formation of ternary oxides at the surface of the alloy. Presence of rubidium and cesium ions in the electrolyte were found to create an additional driving force for lanthanides (La and Ce) to leave the lattice of the alloy, thus, enhancing its corrosion. Corrosion, together with mechanical degradation, were found to be the main reasons of deactivation of LaMm-Ni_4.1Al_0.3Mn_0.4Co_0.45 alloy upon elongated electrochemical treatment.

【 授权许可】

Unknown