Electrochemistry of Pt and Pd under pulse electrolysis conditions

Abstract

Abstract Platinum and palladium are the most suitable electrode materials for studying the kinetics and mechanism of various electrochemical processes. Consequently, their behavior in electrochemical systems has been the subject of extensive study. However, the effect of pulse alternating current (PAC) on Pt and Pd in aqueous electrolytes represents a relatively new area of research for electrochemical process technologies. It was demonstrated that employing PAC with a frequency of 50 Hz to platinum in NaOH electrolyte result in the formation of Pt particles (7.6 nm) containing a PtOx phase (0.25±0.03 wt.%). The dissolution of platinum in NaCl electrolyte resulted in the formation of only platinum chloride complexes. The palladium in the NaOH electrolyte was passivated when PAC was employing to Pd electrodes. In the NaCl electrolyte, the formation of Pd-PdO particles (42±2 wt.% of PdO) was observed. The crystallite size for Pd and PdO was 7.9 and 1.99 nm, respectively. The discrepancy in the chemical properties of two metals belonging to the transition metals of group VIII of the periodic system, which are characterized by the same space group (Fm3m), can be attributed to the combination of electronic and redox properties of Pt and Pd.