Electrodeposition of zinc from slightly acidic gluconate solutions was investigated. Cyclic voltammetric measurements showed inhibition of a cathodic process by sulfate ions. Chronoamperometric study combined with a speciation of individual solutions indicated instantaneous zinc nucleation interrupted by concurrent hydrogen coevolution and release of zinc cations from ZnSO 4 complexes. Morphology of coatings was strongly affected by deposition potentials and a type of zinc salt. Sulfate anions hindered zinc deposition, enhanced development of (100) crystallographic plane and increased cathodic current efficiency. In a presence of chloride ions, zinc growth toward bulk electrolyte and development of (002) crystallographic base plane of hexagonal structure were preferred. Water contact angles (WCA) of zinc deposited from chloride-containing baths revealed the highest values of 131-135°, while the highest WCAs of coatings obtained from sulfate bath reached only 112-119°. Moderately rough and hydrophobic as-plated zinc coatings were characterized by slightly improved corrosion resistance in both neutral and acid solutions.

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