Palladium-Based Catalysts for Oxygen Reduction Reaction in Fuel Cells

Fuel cells, especially low temperature fuel cells are clean energy devices that are expected to help address the energy and environmental problems that have become prevalent in our society. Platinum-based catalysts are usually used as the catalysts for cathode (oxygen reduction) reactions. The high cost and limited resources of this precious metal hinder the commercialization of fuel cells. Pt alone does not present satisfactory activity for the oxygen reduction reaction when used as cathode material. For all these reasons, non-platinum-based catalysts have been tested as electrode materials for low temperature fuel cells. Palladium and platinum have very similar properties because they belong to the same group in the periodic table. Recent efforts have focused on the discovery of palladium-based catalysts with little or no platinum for oxygen reduction reaction (ORR).