Analysis of Oxygen Dissolution Rate from Gas Phase into Nafion Surface and Development of an Agglomerate Model

To clarify the rate determining process for the oxygen transport in a catalyst layer of PEFCs, an oxygen dissolution resistance from gas phase into Nafion surface was measured. The oxygen dissolution resistance, which was estimated form the relationship between Nafion thickness on Pt electrode and the diffusion-limited current density on the electrode, was found to account for a large part of the total oxygen transport loss. By introducing the oxygen dissolution resistance, an agglomerate model was able to predict I-V performance of a PEFC using a reasonable size of agglomerate.