Electrochemical behaviour of electrodeposited Pd and PdNi coatings for the ethanol oxidation reaction in alkaline solution

Electrodeposited Pd and PdNi coating samples were tested for ethanol oxidation reaction (EOR) in alkaline solution using cyclic voltammetry (CV), chronoamperometric (CA) and quasi steady-state measurements. All alloy samples showed higher current densities for the EOR than pure Pd coating. The current density increased with increasing the amount of Pd in the PdNi coating and the most active one was found to be Pd0.74Ni0.26. Based on CA measurements a pseudo-steady state is achieved after 1500 s showing that Pd0.74Ni0.26 is more efficient and poisoning more tolerant than other investigated coatings. Upon the end of the current-time transient, the investigated catalysts were subjected to the potential cycling showing the ability to recover activity loss implying the surface composition stability of binary coatings.