Nanostructured Manganese Oxide Supported onto Particulate Glassy Carbon as an Active and Stable Oxygen Reduction Catalyst in Alkaline-Based Fuel Cells

Alkaline-based fuel cells have garnered renewed interest for low temperature, moderate-power applications since they are amenable to non-precious metal catalysts. We report a new and efficient synthesis route to produce an active and stable catalyst for the oxygen reduction reaction (ORR) in alkaline environments. The catalyst consists of manganese oxide (MnOx) supported onto glassy carbon (GC) particles, which serve as a support material that is more resistant to heat and corrosion than conventional high surface area carbon supports. Impregnation of the MnOx onto the GC particles followed by high-temperature calcination generates a catalytically active Mn3O4 surface with a nanostructured morphology. The MnOx-GC particles display high activity for the ORR in an alkaline electrolyte, comparable to that of best-known non-precious metal catalysts and within 0.15 V of a commercial Pt catalyst. Accelerated durability testing reveals excellent stability of the MnOx-GC catalyst, maintaining nearly 60% of its activity after 30,000 cyclic voltammograms. The catalyst was integrated into the cathode of an alkaline exchange membrane fuel cell (AEMFC) with Pt at the anode, achieving a peak power density of 98 mW/cm(2) at 70 degrees C, demonstrating the viability of the MnOx-GC catalyst in a device environment. (C) 2014 The Electrochemical Society. All rights reserved.