Electrochemical formation of Sm-Co alloy films by Li codeposition method in a molten LiCl-KCl-SmCl{sub}3 system

摘要

Electrochemical formation of Sm-Co alloy films at a Co cathode was studied in a molten LiCl-KCl-SmCl{sub}3 (0.5 mol./)) at 723 K. Very thin film (～100 nm) of SmCo{sub}2 alloy was obtained by potentiostatic electrolysis at 0.20 V (vs. Li{sup}+/Li) for 24 h. Much thicker alloy film ( ～5 μm) was formed by Li codeposition method (cathodic galvanostatic electrolysis at 50 mA cm{sup}(-2)) for 1 h. The formed alloy phase was suggested as Li{sub}xSm{sub}4Co{sub}6 (x ～3). The formed alloy film was changed to various Sm-Co alloy phases by anodic potentiostatic electrolysis depending on the applied potentials. The formation potentials of Sm{sub}2Co{sub}17, SmCo{sub}3, SmCo{sub}3 and Li{sub}xSm{sub}4Co{sub}6 were found to be 1.40, 0.80, 0.30 and 0.05 V, respectively.