Electrochemical studies of Fe and Pd deposition and their influence on the co-deposition of the Fe–Pd alloy

Abstract

Electrodeposition process of the Fe–Pd thin films was investigated using cyclic voltammetry, chronopotentiometry and chronoamperometry methods. Deposition process was first studied for single metals; Fe, Pd. On the end a comparison with Fe–Pd alloy was performed. It was found that the deposition of Fe starts at 50mV, deposition of Pd at 200mV and the deposition of Fe–Pd alloy at 150mV at more positive potentials, when instead of Au electrode as a working electrode Fe, Pd or Fe–Pd monolayered deposits are already present. Furthermore, a comparison of the deposition process of single metals with an alloy reveals that when Fe is accompanied with Pd, the deposition of Fe starts at more than 500mV at more positive potentials. To understand this phenomenon, galvanostatic deposition at −100μA/cm2 for 3600s and potentiostatic depositions from −0.6V to −1.3V were performed with the deposits’ composition and their microstructure studied. It was observed that in the case of the of Fe–Pd-alloy deposition, Pd deposits first and due to its catalytic behaviour it subsequently catalyses the reduction of Fe(II)Cit.