Related Experiment Video
Updated: May 12, 2025
12:12
On the Preparation and Testing of Fuel Cell Catalysts Using the Thin Film Rotating Disk Electrode Method
Published on: March 16, 2018
21.7K
PFSA-Ionomer Adsorption to C and Pt/C Particles in Fuel-Cell Inks
Siddharth Rajupet1,2, Adam Z Weber2, Clayton J Radke1
1Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States.
ACS Applied Materials & Interfaces
|April 29, 2025
Summary
Perfluorosulfonic acid (PFSA) ionomer adsorption onto platinum/carbon (Pt/C) catalyst particles in fuel-cell inks is primarily governed by electrostatic repulsion. This adsorption process is largely irreversible and can be optimized by adjusting ink ionic strength.
Area of Science:
- Electrochemistry
- Materials Science
- Colloid Science
Background:
- Fuel-cell electrodes utilize catalyst inks composed of platinum/carbon (Pt/C) catalyst particles and perfluorosulfonic acid (PFSA) ionomers.
- The adsorption of PFSA ionomer onto Pt/C particles is critical, influencing dispersion properties and the final electrode structure.
Purpose of the Study:
- To characterize the adsorption behavior of PFSA ionomer on Pt/C catalyst particles.
- To understand the factors governing ionomer adsorption and its impact on fuel-cell ink properties.
Main Methods:
- Experimental characterization of PFSA ionomer adsorption isotherms on Pt/C catalyst particles.
- Application of a Smoluchowski-based kinetic adsorption model incorporating DLVO theory for electrostatic interactions.
Main Results:
- PFSA ionomer adsorption is largely irreversible and electrostatically limited by the negative surface charge developed on Pt/C particles.
- Increasing ionic strength of the ink attenuates electrostatic repulsion, promoting ionomer adsorption.
- Adsorption behavior is consistent across varying solvent ratios, catalyst porosity, and Pt loading.
Conclusions:
- The study elucidates the electrostatic mechanisms controlling PFSA ionomer adsorption on Pt/C catalysts.
- Findings provide insights for tailoring fuel-cell inks to optimize electrode structure and enhance fuel-cell performance.
