Electrodepostion of compact cadmium deposits in the non-aqueous ethylene glycol solution modified with ethanol

Using non-aqueous solvents for metal electrodeposition can suppress hydrogen evolution reactions, thereby preventing hydrogen embrittlement in metallic structural materials. Ethylene glycol, which has a large solubility for metal acetates, might be a good non-aqueous solvent candidate. However, its relatively high viscosity and poor wettability lead to forming loose metal deposits during the electrodeposition, which is not suitable for anticorrosion applications. In this work, we modify the ethylene glycol solution by adding ethanol and systematically investigate the roles of ethanol concentration, deposition potential, and temperature on the physical properties of the solution, electrochemical behavior of cadmium deposition, and microstructure of the deposits. Our results show that adding ethanol significantly reduces the viscosity of the electrolyte and improves its interfacial wettability, which promotes the formation of compact and thick deposits.