Three-Dimensional Spatial Distributions of Pt Catalyst Nanoparticles on Carbon Substrates in Polymer Electrolyte Fuel Cells

The Fuel Cell Electrode (FCE), consisting of platinum particles or platinum alloy particles supported on carbon substrates, is one of the key components in the polymer electrolyte fuel cells (PEFCs). In order for the detailed characterization, it is crucial to determine three-dimensional (3D) morphologies of Pt nanoparticles on carbon substrates (Pt/C). In this communication, 3D structures of Pt/C with two different kinds of substrates have been examined using a nano-scale 3D imaging technique, transmission electron microtomography. It was found that the TEC10V50E had Pt catalytic nanoparticles located only at the substrate surface, while the TEC10E50E showed Pt nanoparticles both inside and at the surface of the carbon substrate.