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Updated: Jun 25, 2025
09:02
Synthesis of Platinum-nickel Nanowires and Optimization for Oxygen Reduction Performance
Published on: April 27, 2018
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Poly(ionic liquid) Ionomers Help Prevent Active Site Aggregation, in Single-Site Oxygen Reduction Catalysts.
Silvia Favero1, Alain Li1, Mengnan Wang1
1Department of Chemical Engineering, Imperial College London, SW7 2AZ London, U.K.
ACS Catalysis
|May 23, 2024
Summary
This study reveals the significant, overlooked impact of ionomers on anion exchange membrane fuel cells (AEMFCs). Developing new poly(ionic liquid) ionomers improves oxygen transport and catalyst layer morphology for better performance.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Conversion
Background:
- Anion exchange membrane fuel cells (AEMFCs) offer platinum-free cathode catalysis for clean electricity.
- Research has primarily focused on catalysts and membranes, neglecting the ionomer's role.
- The ionomer's influence on AEMFC performance and durability remains underexplored.
Purpose of the Study:
- To investigate the effect of a novel poly(ionic liquid)-based ionomer on AEMFCs.
- To compare this ionomer's impact on oxygen transport and reduction kinetics against commercial ionomers (Nafion, Fumion).
- To correlate ionomer properties with catalyst layer morphology and fuel cell performance.
Main Methods:
- Development of a poly(ionic liquid)-based ionomer.
- Comparative analysis of oxygen transport and oxygen reduction reaction (ORR) kinetics using Nafion and Fumion as benchmarks.
- Characterization of catalyst layer morphology and iron aggregation.
- Rheological analysis of catalyst ink.
- Performance testing using rotating disc electrode (RDE) and gas diffusion electrode (GDE) configurations.
Main Results:
- The choice of ionomer significantly alters catalyst layer morphology and iron aggregation.
- Catalyst layer quality and iron aggregation correlate with catalyst ink rheology.
- Poly(ionic liquid)s with fluorinated anions demonstrate improved oxygen diffusion compared to Nafion.
- Significant performance discrepancies were observed between RDE and GDE testing due to differing catalyst layer morphologies.
Conclusions:
- The ionomer plays a critical, often underestimated, role in AEMFC performance and durability.
- Poly(ionic liquid) ionomers show promise for enhancing oxygen transport in AEMFCs.
- The limitations of RDE testing in predicting actual fuel cell performance are highlighted, emphasizing the need for GDE evaluation.
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