Ion conducting nanofiber fuel cell electrodes
Overview
Proton exchange membrane fuel cells (PEMFCs) boast high efficiency, high energy and power density, low-temperature operation, rapid start-up time, and incorporation of fuels from renewable sources with no point-of-use greenhouse gas emissions. Consequently, PEMFCs have attracted considerable interest as alternative power sources for large market applications, such as transportation (hydrogen fuel cells) and portable electronics (methanol fuel cells). However, high cost due to the required precious metal (Pt) electrodes has severely limited their mass commercialization. Drexel researchers have recently developed a new process to fabricate high surface area fuel cell electrode structures based on super ion conducting nanofibers. The process combines eletrospinning of super proton conductive polymer nanofibers with electrospraying of nanosized electrocatalyst particles (platinum on carbon = Pt/C). This process produces a high surface area electrode, where there is more available catalyst surface area for the oxygen reduction reaction to occur, which is the rate-limiting step in fuel cells. Therefore, a true significant reduction in Pt can be achieved in these new nanofiber electrodes. Furthermore, our modeling suggests that much higher power densities can be achieved at these ultra-low commercially attractive Pt loadings.
Applications
- Alternative power sources for large market applications, such as transportation (hydrogen fuel cells) and portable electronics (methanol fuel cells).
Advantages
- Greater Efficiency: Process allows fabrication of cells with more surface area for the oxygen reduction reaction to occur, increasing the rate of the reaction and the current of the cell.
- Reduced Need for Costly Precious Metals: our process shows high fuel cell power density at Pt loadings that are 40 times lower than typical Pt loadings used in state-of-the-art fuel cells
Intellectual Property and Development Status
United States Patent Issued- 11,469,423
References
Wang, X.; Richey, F.W.; Wujcik, K.; Ventura, R.; Mattson, K.; Elabd, Y.A. Effect of Polytetrafluoroethylene on Ultra-Low Platinum Loaded Electrospun/Electrosprayed Electrodes in Proton Exchange Membrane Fuel Cells. Electrochimica Acta 2014, 139, 217-224.
Commercialization Opportunities