Highly dispersed platinum supported catalysts - Effect of properties on the electrocatalytic activity

This work addresses scientific issues regarding the most challenging component of PEM fuel cells, the electrocatalyst, and explores a new approach to exploit the differentiations induced to the metal by the surface chemistry of the support. The study focuses on the development of Pt based electrocatalysts supported on pyridine modified carbon nanotubes with different Pt loadings, their thorough characterization and parallel comparison with non-modified or conventional carbon supports. The aim is the interpretation of the catalyst electrochemical behavior through a structural and physicochemical characterization study. The introduction of pyridines can differentiate the metal deposition, in terms of dispersion, nanoparticle properties, platinum oxidation state and metal-support interactions. Moreover, the substrate can play a decisive role on the size and functionality of the electrochemical interface. This approach constitutes a promising route for developing materials with innovative features aiming to a serious reduction in the Pt loads through increased activity and metal utilization.