Porous Pd films as effective ethanol oxidation electrocatalysts in alkaline medium

Porous Pd films are successfully electrodeposited within hydrogen bubble dynamic templates for the first time, characterized by SEM, EDS, XRD, cyclic voltammetry and chronoamperometry. The effects of the NH4Cl concentration and deposition time on the morphology are studied. The real surface area and pore size can be controlled easily by modulating the electrolyte composition and deposition time. The as-prepared Pd films have a high geometric efficiency, ensuring a large number of active sites and rapid reaction rates. The porous Pd films with different pore size show different electrocatalytic stability. Amperometric current of ethanol oxidation decays fast on the films with small pores. Porous Pd films with a larger pore size show high electrochemical activity and stability for ethanol electro-oxidation in an alkaline medium.