Investigation of Transport-Reaction Phenomena in Multi-Layered PEFC Cathode Catalyst Layer

Abstract

Improvement in power generation performance of Polymer Electrolyte Fuel Cell (PEFC) is required for its market supremacy. The microstructure of cathode catalyst layer (CCL) is known to dictates the power generation performance of PEFC. Also, the requirement for the species transport characteristics should vary with the thickness-wise position in CCL. In this report, we fabricated three kinds of multi-layered CCL that has the difference in I/C ratio of 2nd layer, and investigated oxygen transport-reaction phenomena by evaluation polarization characteristics, electrochemical surface area and oxygen transport resistance in the CCLs using limiting current measurements. As these results, it was found that there is an optimization strategy of I/C ratio in 2nd CCL.