Hydrogen Fuel Cell Catalysts and Support
A highly stable porous graphitic carbon support for Pt-based catalysts used in proton exchange membrane fuel cells
Proton exchange membrane fuel cells (PEMFC) are the leading technology for hydrogen fuel cell vehicles. However, broad PEMFC commercialization has been limited by factors including high cost, insufficient durability, and limited power density. Because over 40% of the current cost of PEMFCs is due to the need for Pt catalysts to help drive the otherwise sluggish oxygen reduction reaction (ORR) at the cathode, which governs the overall performance of PEMFCs, most efforts to improve PEMFCs have been focused on reducing or replacing Pt. Pt-metal alloys have been explored and hold promise, but their carbon supports are vulnerable to corrosion under harsh operating conditions, leading to poor performance durability.
This invention provides porous graphitic carbon (PGC) supports that are highly graphitized to resist corrosion. These PCG supports possess a high surface area (~500 m2/g) as well as a favorable environment to disperse Pt nanoparticles and prevent agglomeration. Further, they significantly enhanced activity and stability with Pt catalysts in membrane electrode assembly tests. For example, after 5,000 cycles, the PGC-supported Pt catalyst lost only 9 mV at a current density of 1.5 A/cm2 while the commercial carbon-supported Pt catalyst lost 200 mV.
Compared with the commercial Pt/C catalyst, PGC-supported Pt exhibited one-fifth the corrosion rate.
Proton exchange membrane fuel cells
US Provisional Patent Application 63/051,703 filed July 14, 2020.
Available for licensing or collaboration.