Hydrogen evolution assisted electrodeposition of bimetallic 3D nano/micro-porous PtPd films and their electrocatalytic performance

Self-supporting PtPd bimetallic catalysts with three-dimensional (3D) porous structures and a greatly enhanced surface area are firstly fabricated at a glassy carbon electrode (GCE) by a one-step strategy of potentiostatic co-electrodeposition utilizing hydrogen bubble dynamic templates. The atomic ratio of Pt/Pd in the bimetallic catalysts is varied by changing the composition of the electrodeposition solution. The 3D porous PtPd films are characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) and examined as electrocatalysts for the electro-oxidation of methanol using cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). Experimental results demonstrate that a small amount of Pd plays the predominant role in the formation of 3D porous structure for PtPd bimetallic catalysts and is an excellent catalytically enhancing agent for the Pt catalyst towards methanol electro-oxidation. The study on electrocatalytic performance of mono and bimetallic catalysts towards formic acid electro-oxidation also reveals the better activity of 3D porous Pd film for this reaction.