(Invited) Additive Dual Nano Catalysts to Accelerate Oxygen Reduction Reaction in Cathode of Solid Oxide Fuel Cells

Abstract

The sluggish oxygen reduction reaction (ORR) in the cathode is hindering the power density of the solid oxide fuel cells (SOFCs). Infiltration of catalyst into the cathode of SOFCs is promising to accelerate the ORR. However, the degradation associated with the coarsening of infiltrated nano-catalyst is intense. To stabilize the catalyst, a ultra-thin ~5 nm Atomic Layer Deposition (ALD) is employed to coat a dual electrocatalyst into the porous lanthanum strontium manganite (LSM)/yttria-stabilized zirconia (YSZ) cathode. After 504 h operation at 750 °C, the ALD coating resulted in the SOFC peak power density enhancement by ~200 %. Remarkably, the nano-catalysts with ~ 10 nm in dimensions, are uniformly distributing on YSZ grain surface, triple phase boundaries and at LSM/LSM surface grain boundaries after 504 h operation at 750 °C. This study demonstrates an effective approach of stabilizing the nano-sized and minute amount of catalysts for enhancing ORR activity at elevated temperatures.