Electroplating of dysprosium, electrochemical investigations, and study of magnetic properties

Electroplating of dysprosium from several nonaqueous solutions and from an ionic liquid was studied. Dysprosium metal was used as the anode material, and several metals and a silicon wafer with a vacuum-deposited gold layer were used as cathode materials. Dysprosium was successfully electroplated from dimethylformamide-based solutions with high coulombic efficiency. The resulting dysprosium layer was effectively protected vs reactions with water and oxygen from air by electroplating an aluminum layer onto dysprosium from a nonaqueous electrolyte. All processes were investigated by electrochemical methods including cyclic voltammetry, chronoamperometry, chronopotentiometry, and with the help of an electrochemical quartz microbalance coupled to an Autolab PGSTAT30 controlled by the GPES software from Eco Chemie B.V., Utrecht, The Netherlands. A nonaqueous reference electrode developed by Izutsu was applied; the diffusion potential was kept low by a slight modification of his original proposal. X-ray fluorescence spectroscopy was used to verify electroplating of Dy. The presence of metallic Dy was also confirmed by superconducting quantum interference device magnetometry which showed a ferromagnetic moment at 5 K.