Performance of Solvent Substituted Ionomer Dispersions in Catalyst Layer for Hydrogen-Based Energy Conversion Devices

Catalyst inks for the preparation of porous catalyst layer for hydrogen-based energy conversion devices is composed of electrocatalyst, ionomer dispersion and additional solvents. Solvents have an important role in determining the size of ionomer aggregates, the properties of catalyst ink and the morphology of catalyst layer. It has been reported that the solvents for ionomer dispersions substantially influenced the size of ionomer aggregates and finally resulted in the performance and durability. To understand a deep insight into solvent-ionomer molecular interaction, solvation energy obtained by molecular design modeling for a measurement of the relative solubility of ionomers in solvents was studied in this study. In this study, we investigated the solvent-ionomer molecular interaction using molecular design modeling simulation and experimental validation in proton exchange membrane fuel cell and water electrolysis. In addition, I-V polarization curves, cyclic voltammetry and electrochemical impedance spectroscopy were measured and analyzed in terms of solvent property and solvation energy. Acknowledgment This research was supported in part by the Hydrogen Energy Innovation Technology Development Program of the National Research Foundation (NRF) funded by the Ministry of Science, ICT & Future Planning(NRF-2019M3E6A1063677) and by the New and Renewable Energy of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20213030040520).