Dual mechanism of hydrogen desorption from palladium alloys postulated on the basis of cyclic voltammetric studies

The process of hydrogen absorption/desorption in Pd-Pt and Pd-Pt-Rh alloys has been investigated using cyclic voltammetry. Hydrogen absorbed at constant potential was electrooxidized at various scan rates. The charge of hydrogen oxidation has been found to be dependent on the scan rate. The decrease in the oxidation charge observed for low scan rates indicates that, under these conditions, some amount of hydrogen may be removed via a non-electrochemical recombination reaction. The results suggest that the dual mechanism of hydrogen desorption, involving electrochemical oxidation and non-electrochemical recombination, confirmed for pure palladium, is valid also for palladium alloys.Contribution to the 3rd Baltic Conference on Electrochemistry, GDASK-SOBIESZEWO, 23–26 APRIL 2003.Dedicated to the memory of Harry B. Mark, Jr. (February 28, 1934–March 3rd, 2003)