Anca Cojocaru

Electrochemical Study and Electrodeposition of Copper(I) in Ionic Liquid-reline

The authors made the electrochemical studies on the electrode processes during copper electrodeposition with ionic liquids-reline as an electrolytic medium. Reline is a commercial name for a eutectic mixture of choline chloride and urea(1:2, molar ratio). This new proposed method of copper deposition is an ecological one because the ionic liquids are recyclable, non-volatile and non-toxic. Cyclic voltammetry investigations were conducted at 343 and 353 K in choline chloride-urea(Reline) deep eutectic solvent with single salt CuCl(generally in 0.05–0.38 mol/L concentration range). Electrochemical impedance spectroscopy investigations were conducted in choline chlorideurea ionic liquid with CuCl(0.05 mol/L). We investigated both cathodic and anodic processes of Cu+ ions at different sweep rates in this new electrolytic system based on choline chloride. We have proposed by this an alternative to the classical copper electrodeposition. Coefficient of diffusion, D0, for the system Reline-CuCl is presented and the value of D0 is 1.22×10−8 cm2/s.

Electrodeposition of Co and CoMo alloys coatings using choline chloride based ionic liquids - evaluation of corrosion behaviour

This study deals with the electrodeposition of Co and CoMo alloys from various ionic liquids based on choline chloride (ChCl) – urea and ChCl – ethylene glycol eutectic mixtures. The Co and Co–Mo (with 1–8 wt-% Mo content) deposits obtained were adherent, compact and uniform onto copper substrates. A decrease of the Mo content in the alloy has been shown as the applied current density increased in the range of 7–25 mA cm−2, at 90–100°C. Some peaks assigned to MoO3 or Co3Mo phases have been identified in the XRD patterns. The average size of crystallites has been estimated to be in the range of 7–9.2 nm (nanocrystalline deposits). Atomic Force Microscopy analysis gave evidence that Co deposits were formed by multiple compact almost rounded crystallites, while Co–Mo alloy ones consisted of multiple relatively compact grains with cylindrical shape. The coatings’ corrosion performance has been also measured by continuous immersion testing in 0.5M NaCl solution, and potentiodynamic polarisation and electrochemical impedance spectra.

Considerations on Reducing the Experimental Duration of Electrochemical Impedance Spectroscopy Measurements Used for the Evaluation of Ionic Conductivity in Polymer Electrolyte Membrane Electrolysers and Fuel Cells

In this paper one attempted to discuss the effect of reducing the experimental duration of electrochemical impedance spectroscopy (EIS) measurements by reducing the sampling frequency without affecting the measured parameters. The experimental setup is based on a novel cell consisting of two electrodes or three electrodes cell configuration. The experimental layout allows a precise evaluation of the membrane thickness, at micrometer resolution, during the determination of the electrochemical impedance spectra.