Evaluation of the Durability of a Metal-Organic Framework Catalyst in High-Temperature Proton Exchange Membrane Fuel Cells (HT-PEMFCs)

Abstract

A non-pgm Metal Organic Framework (MOF) catalyst was evaluated for durability in the high-temperature environment associated with HT-PEMFCs under various conditions. Due to the higher PGM loading typically required for these systems, it is an ideal candidate for research regarding non-PGM catalysts. However, a common issue regarding non-PGM materials is their lack of durability in the low temperature humidified environment of a PEMFC, and until these issues are resolved, it will continue to provide a hindrance towards mass commercialization. Prior work had demonstrated the high performance of this particular catalyst[1], initially in RDE and low temperature fuel cells, and now in HT-PEMFCs. Membrane Electrode Assemblies (MEAs) were tested at 200˚C using a commercial polybenzimidazole (PBI) membrane, and were evaluated under several durability criteria, including constant voltage testing at various potentials (for demonstration of prolonged use), temperature cycling (to mimic startup/shutdown) and corrosion testing to evaluate losses in these primarily carbon-based materials. Early indications demonstrate a highly stable catalyst, as after nearly 40 hours of non-continuous chronoamperometric testing, the fuel cell demonstrated negligible performance losses at 650mV in air at 2.5bar total pressure. Acknowledgment: The authors gratefully acknowledge the financial support from the Department of Energy-Energy Efficiency and Renewable Energy, Fuel Cell Technology Office under an Incubator grant (DE-EE0006965). Use of the Stanford Synchrotron Radiation Light source, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. Use of Beamline 2-2 at SSRL was partially supported by the National Synchrotron Light Source II, Brookhaven National Laboratory, under U.S. Department of Energy Contract No. DE-SC0012704. Use of the beamline 9-BM in Advanced Photon Source, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under Contract No. DE-AC02-06CH11357. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.