Congratulations to our PhD candidate Andrea Volpe for his work entitled “Evaluation of physicochemical properties and metal electrodeposition from deep eutectic mixtures based on choline chloride and cobalt chloride hexahydrate” published on the Journal of Molecular Liquids.

Deep Eutectic Solvents (DESs) are a new class of liquid mixtures exhibiting tunable physicochemical properties as a function of the nature and ratio of their components. In this study the preparation, characterization, and application of mixtures with different molar ratios of choline chloride–cobalt chloride hexahydrate was investigated. To assess the eutectic nature of the mixtures, the phase transitions of the mixtures have been studied in detail by Differential Scanning Calorimetry (DSC) and the eutectic composition was found to be close to the molar ratio 2:1 of choline chloride: CoCl₂·6H₂O. The thermal stability, electrical conductivity, viscosity, density, and electrochemical window (EW) as a function of temperature and mixture composition were also characterized. The amplitude of the EW varied depending on the mixture composition, ranging from 1.8 to 2.7 V. This is the first report of a variation in EW ranges for different mixture compositions in Type-II DES literature. Electrodeposition of uniform layers of cobalt was achieved by chronoamperometry with very low content of impurities and displayed different morphologies depending on mixture composition and applied overpotential.

The paper is available at the following link: https://doi.org/10.1016/j.molliq.2025.127937