The effect of water addition on physicochemical properties of electrochemical systems based on deep eutectic solvents

Abstract

We investigated the effect of water addition on physicochemical properties of ionic liquids containing (i) chromium chloride, choline chloride and water in the molar ratio of 1:0.5:x, and (ii) choline chloride, ethylene glycol, nickel chloride and water in the molar ratio of 1:2:1:x, (x = 6, 9, 12, 15 or 18) for the temperatures between 25 and 80°C. An increase in the water content resulted in decreasing density, viscosity and surface tension and increasing conductivity. The obtained results were interpreted in terms of hole theory. The introduction of water was stated to have a beneficial effect on the electrodeposition of chromium and nickel coatings.