Development of Gas Diffusion Electrodes for Polymer Electrolyte Fuel Cells

The historical development and current status of gas diffusion electrodes for polymer electrolyte fuel cells ( PEFCs) are presented. Two and three-layer electrodes are compared. The effects of both the characteristics and the amount of the materials composing the electrode on the cell performance are presented. These include: the characteristics of the porous substrate; the wettability of the diffusion layeer; the characteristics of the catalyst, which is commonly platinum supported on carbon (Pt loading, Pt particle size, Pt/C ratio, Pt deposition method); the presence of perfluorosulfonate ionomer; and the way that the catalytic layer is filled. Attention is also given to the fabrication process of the electrodes and thermal treatments.