Speaker
Description
Rare earth elements (REEs), particularly dysprosium (Dy), are critical for development of future clean energy technologies. However, their recovery from end-of-life (EOL) NdFeB magnets faces significant challenges and has not been widely implemented at the industrial scale. Improving resource efficiency requires the development of recycling and recovery methods for REEs from EOL waste using cost-effective and environmentally friendly technologies. Deep eutectic solvents (DESs) present a promising alternative due to their low cost, simple preparation, low toxicity, and wide electrochemical window1, compared with conventional high-temperature molten salt electrolytes commonly used for electrolysis.
In this study, the electrochemical reduction and deposition of Dy(III) were investigated for the first time, in a choline chloride and ethylene glycol (1:2, ChCl:EG) deep eutectic solvent (Ethaline) at 70 °C using a gold working electrode. Cyclic voltammetry (CV) and square wave voltammetry (SWV) in 0.1 M DyCl₃–Ethaline electrolyte revealed a single-step, irreversible three-electron transfer process for the reduction of Dy(III) to Dy(0). Potentiostatic deposition at −0.800 V vs. Ag for 4 h produced deposits whose morphology, elemental composition, and surface chemical states were characterized by SEM, EDS, and XPS. The combined analyses confirmed the formation of metallic dysprosium. These results demonstrate the potential of Ethaline as an environmentally friendly medium for the low-temperature electrodeposition of rare earth metals. This approach offers a sustainable pathway for recovering critical materials from EOL and contributes to the development of greener recycling technologies.
Keywords:Choline Chloride-Ethylene Glycol, Dysprosium, Rare earth elements, Deposition
Acknowledgement: This research was supported by the Science Fund of the Republic of Serbia, #Grant No. 270, Applying advanced product intellectual properties and industrialization workflows to innovative fundamental research ideas in the area of rare earth electrochemical recovery – REMEDIS. V.S.C. and N.M.P. acknowledge the financial support received from the Ministry of Science, Technological Development and Innovation of the RS (Contract No: 451-03-33/2026-03/200026).
References:
1. Cvetković, V.S.; Petrović, N.M.; Nikolić, N.D.; Jovićević, J.N.; Influence of Cu(II) Ion Concentration on Copper Electrodeposition from Deep Eutectic Solvent on Inert Substrate, Metals, 2025, 15, 716. https://doi.org/10.3390/met15070716.