Sono-electrodeposition (20 and 850 kHz) of copper in aqueous and deep eutectic solvents

This paper reports the effects of ultrasound at different frequencies and powers upon the electrodeposition of copper(II) chloride in aqueous potassium chloride and in glyceline 200 (a deep eutectic solvent – DES) on Pt electrodes in the potential range for copper deposition and dissolution. It is shown that the deposition of copper in both solvents is greatly affected by ultrasound at the two frequencies of 20 and 850 kHz employed. Limiting current densities were obtained in both solvents under sonication at 20 and 850 kHz and a 10-fold and 5-fold increase in currents in aqueous potassium chloride and glyceline 200 compared to silent conditions was observed respectively. The difference in viscosity of water (KCl) and glyceline 200 was found to be a crucial parameter in the evaluation of limiting current densities.