An FIB-SEM Study on Correlations between PEFC Electrocatalyst Microstructure and Cell Performance

摘要

The electrocatalyst layer of the polymer electrolyte fuel cells (PEFCs) has a complicated porous microstructure. Since the porous nanostructure allows the transport of reactant gas, water vapor, protons, and electrons, cell performance depends strongly on their 3D microstructure. Understanding the correlations between the electrocatalyst microstructure and the cell performance is therefore essential for further improving the PEFC electrochemical performance. In this study, these correlations are quantitatively considered by using the focused-ion-beam coupled scanning electron microscopy (FIB-SEM) technique. In particular, while it is difficult to distinguish between the solid and the pore of the electrocatalyst layer due to the complicated porous nanostructure, this problem has been solved by the auto-image thresholding technique.