Pulse electrodeposition of catalyst nanoparticles for application in PEM fuel cells

A simple method for the preparation of nanostructured low loading Pt, PtNi and PtCo electrodes for application in PEM fuel cells is proposed. For high utilisation, the catalyst nanoparticles are directly deposited on the microporous layer (MPL) of a commercially available gas diffusion layer by pulse electrodeposition. A special challenge for electrodeposition, in this study, was the hydrophobic character of the MPL. For a homogenous fine-grained electrodeposition, an activation treatment of the substrate surface was advantageous. Plasma etching of the surface, before electrodeposition, significantly improved fuel cell performance. Furthermore, the effects of electrolyte and electrodeposition parameters have been investigated in detail. For use as catalyst, nucleation should be predominant to enable a large surface area. Several electrochemical and optical techniques, including cyclic voltammetry, SEM, XRD, X-ray fluorescence analysis and IR spectroscopy, were used to investigate the catalytically relevant parameters of the deposited nanoparticles.