Gravimetric Studies of Ni Electrodeposition with Additives from Deep Eutectic Solvents Using Electrochemical Quartz Crystal Microbalance EQCM

Abstract

The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in either a1choline chloride: 2 ethylene glycol (ethaline) or 1 choline chloride: 2 urea (reline) based ionic liquid. The possibility of adapting the Quartz Crystal Microbalance EQCM (which measures the mass attached to the electrode) to probe kinetics of electrochemically-driven solid state phase transformations has been explored in a Ni electrodeposition in absence and presence of complexing agents ethylene diamine en and acetylacetonate acac from both electrolytes ethaline and reline. The study shows that the current efficiency and the rate of deposition of nickel coatings obtained from ethaline and reline baths in absence of brighteners en and acac are different, and the addition of en and acac to both ionic liquid solutions results in a significant decrease current. And the associated growth rate will also be decreased, suggesting that the en acac stops the formation and growth of Ni nuclei. This suggests that the mechanism of growth is changed.