Low Humidifying Proton Exchange Membrane Fuel Cells with Enhanced Power and Pt–C–h-SiO2 Anodes Prepared by Electrophoretic Deposition

Hydrophilic anodes were prepared by electrophoretic deposition using a slurry containing hollow SiO2 (h-SiO2) nanospheres and commercial Pt–C nanocatalysts. Low humidifying membrane–electrolyte assemblies (MEAs) were then prepared, which were incorporated into single proton exchange membrane fuel cells (PEMFCs). The effect of humidity on the cell voltage and that of the h-SiO2 mass fraction on the MEA power performance and resistance were examined. The MEA stability was evaluated. Adding h-SiO2 nanospheres to the catalyst increased the Pt mass activity from 1997 to 2657 A/gPt at an operating voltage of 0.6 V at a 100% relative humidity (RH); it increased from 1557 to 2611 A/gPt at 0.6 V and 30% RH. The current density voltage (i–V) and electrochemical-impedance results showed that the addition of h-SiO2 reduced both anode activation loss and ohmic polarization. In addition, the low humidifying MEAs exhibited the same i–V relationship over a wide humidity range. After long-term operation in the absence of moisture, the cell voltage of a standard MEA was found to reduce by 15.55% whereas that of our proposed single cell dropped by only 7.18%. The power density of our proposed MEA was enhanced by a factor of 1.5 relative to a regular MEA.