Cold-Rolled Binary Palladium Alloys with Copper and Ruthenium: Injection and Extraction of Atomic Hydrogen

The effect of annealing and chemical composition of cold-rolled palladium–copper (57 at % Cu) and palladium–ruthenium (6 at % Ru) alloys on the processes of injection and extraction of atomic hydrogen in an aqueous solution of 0.1 M H 2 SO 4 was studied by two-stage cathode–anode chronoamperometry. The close values of the parameters of hydrogen permeability, found from the cathode and anode chronoamperograms, indicate a low level of imperfection of the alloy structure. It has been established that the choice of a mathematical model for processing the chronoamperometry results is determined by the thickness of the alloy samples. The finite-thickness model can be applied if the sample thickness does not exceed 10 µm. Preliminary annealing of samples leads to a decrease in hydrogen permeability and an increase in the effective rate constants of the injection and extraction of atomic hydrogen. At the same time, the palladium-ruthenium alloy is characterized by a higher rate of diffusion mass transfer, while the copper–palladium alloy is characterized by increased values of the kinetic parameters of atomic hydrogen transfer.