Electrodeposition of AuCo alloys and multilayers

AuCo alloys and Au/Co multilayers have been fabricated by electrodeposition from non cyanide-containing electrolytes. The effect of pH and citric acid concentration on the deposit composition and current efficiency was investigated. Results showed that a lower citric acid concentration (0.47 M) at pH 6.15 was favored for multilayered Au/Co deposits with disparate compositions in each layer. An increase in the citric acid concentration or pH requires a larger applied current density to achieve the same cobalt concentration, and results in a drop of current efficiency.