Resolving Electrode Morphology’s Impact on Platinum Group Metal-Free Cathode Performance Using Nano-CT of 3D Hierarchical Pore and Ionomer Distribution

• DOI: 10.1021/acsami.6b08844
• Publication Date: 2016-11-02T14:56:44Z
• Authors: Siddharth Komini ...; Hoon T. Chung; Piotr Zelenay; Shawn Litster
• Keywords: Ionomer; Nafion; Membrane electrode assembly

This article reports on the characterization of polymer electrolyte fuel cell (PEFC) cathodes featuring a platinum group metal-free (PGM-free) catalyst using nanoscale resolution X-ray computed tomography (nano-CT) and morphological analysis. PGM-free PEFC have gained significant interest in past decade since they potential to dramatically reduce costs by eliminating large (Pt) raw material cost. However, several challenges remain before are commercially viable. Since these catalysts lower volumetric activity, thicker subject increased gas proton transport resistances that performance. To better understand efficacy improve electrode performance, detailed understanding correlation between fabrication, morphology, performance is crucial. In this work, pore/solid structure ionomer distribution was resolved three dimensions (3D) nano-CT for electrodes varying Nafion loading. The associated properties were evaluated from pore/particle-scale simulations within nano-CT-imaged structure. These characterizations then used elucidate microstructural origins dramatic changes with We show primarily result distinct ionomer's spatial distribution. impact morphology highlights importance development concert efforts activity durability.