Coupled System of Modified Membrane and Modified Cathode for Efficient PEM-FC

A coupled system formed by polyoxometalate (POM)-modified ultra-low Pt loading cathode and sulphated titania (S-TiO2)-doped Nafion membrane is evaluated in a proton exchange membrane (PEM) fuel cell (FC). Modification of fuel cell cathode is performed using Kegging-type polyoxometalate and low Pt loading, in order to enhance active area and mesoporosity [1]. Commercial Nafion is modified with superacidic sulphated titanium oxide nanoparticles, in order to improve the proton transfer and the hydration level in the membrane-electrode assembly (MEA) [2,3]. The cell performance is studied at different relative humidity with polarization dependence and electrochemical impedance spectroscopy at high and low current density. Analysis of cell performance shows that the catalytic and transport properties are improved, with respect to unmodified commercial materials, using the coupled system, despite the ultra- low Pt loading used, thanks to rich proton environment provided from both cathode and membrane.