Effect of Catalyst Ink Properties on the Performance of Proton Exchange Membrane Fuel Cell and Water Electrolyzer: A Mini Review

The usual way to create the catalyst layer in electrochemical energy conversion cells involves combining catalyst, ionomer dispersion, and solvents. When this ink dispersion is processed, the resulting microstructure and rheological properties of the catalyst ink are influenced by the components composition and how they interact each other. Once the catalyst ink is dried, it forms the microstructure of the catalyst layer (CL), which includes agglomerates and pores that can impact the catalyst activity and the mass transport performance. As a result, examining the correlation between the catalyst ink characteristics and the CL structure is highly valuable. Recently, numerous studies have explored the relationship among the rheological properties of the catalyst ink, the structure of the CL, and the performance of the cell. In this review, we examine how the composition and rheological properties of the catalyst ink influence cell performance and compare the findings of these studies to provide insights into creating high-performance catalyst ink.