Using the Palladium as core and Platinum as shell for ORR

Abstract

In this work, electrocatalyst with core-shell structure (Pd as core and Pt as shell on VulcanXC-72R) was synthesis. Not only this structure can reduce the amount of platinum but it also can increase the gas diffusion electrode (GDE) performance in cathode reaction (Oxygen Reduction Reaction or ORR) of polymer electrolyte membrane fuel cell (PEMFC). To this meaning, one series of electrocatalyst with different molar ratio of metals (Pd @ Pt), was prepared and applied in electrode fabrication. The used synthesis method was impregnation with hydrothermal. The performance of the electrodes in ORR was studied by linear sweep voltametery (LSV), electrochemical impedance spectroscopy (EIS), chronoamperometery techniques and the MEA were also tested. Inductive coupled plasma (ICP), X-ray diffraction (XRD), transmission electron microscopy (TEM) techniques was used to characterize the electrocatalyst. The results indicated that the electrocatalyst with 3:1 molar ratio for Pd: Pt enhanced the cathode in MEA performance. This result can be attributed to the positive effect of Pd, particle size and catalyst distribution on substrate that consequently, provide the best three phase zone.