Electrodeposited Zn for Water-Repellent Coatings

Abstract

We show that mildly alkaline electrolytes can be used to produce Zn coatings that improve the water repellent properties of stainless steel. Optimal Zn deposits were prepared under potentiostatic conditions from electrolytes that contained ZnCl2, NH4Cl, and a surfactant (polyethyleneimine). After deposition, the Zn electrodeposit was capped with stearic acid to prevent oxidation and to provide a lower surface energy. The capped electrodeposits display an impressive degree of water repellency, including extremely poor water droplet adhesion. We discuss the range of deposition parameters (electrolyte composition, pH, and applied potential) that produce the best water-repellent electrodeposits.