On‐line characterization of PEM 's oxygen permeability for PEM fuel cell by embedded microelectrode method

Pt-doped proton exchange membranes (PEMs) can effectively reduce oxygen permeation and thus enhance the durability of PEM, which have been widely employed in fuel cell. However, until now, no study related to the oxygen permeation capability of Pt-doped PEM during actual operation has been reported. In this article, the oxygen permeation of Pt-doped PEM under fuel cell operation is analyzed by the embedded microelectrode method. The test results show that the anode/cathode pressure difference is the main influencing factor for the oxygen permeation of the PEM: the oxygen permeation behavior of the Pt-free PEM exists and gradually decreases with an increase in the anode/cathode pressure difference, and the oxygen permeation behavior of the PEM disappears when the pressure difference exceeds 60 kPa. Due to the presence of Pt nanoparticles, the Pt-doped PEM exhibits negligible oxygen permeation in the anode/cathode pressure difference from −100 kPa to 100 kPa and demonstrates excellent oxygen consumption ability.