Influence of polyethoxylated additives on zinc electrodeposition from acidic solutions

The influence of several ethoxylated additives (ethyleneglycol and polyethy leneglycol polymers of different molecular weights) on the nucleation, grow th mechanism and morphology of zinc electrodeposited from an acidic chlorid e bath is reported. The electrochemical study was carried out using cyclic voltammetry, inversion potential and chronoamperometric techniques. The dim ensionless graphs model was applied to analyse the nucleation process and t he results showed that the studied additives have a blocking effect on the electrodeposition of zinc. This effect occurs in the first stages of the nu cleation process and is dependent on the molecular weight of the additive. Changes induced by the presence of additives in the morphology and grain si ze of the deposits were observed using SEM analysis. Results show that the presence of additives modifies the nucleation process and determines the fi nal properties of the deposits.