A gas-diffusion cathode coated with oxide-catalyst for polymer electrolyte fuel cells using neither platinum catalyst nor carbon catalyst-support

To overcome the fundamental disadvantages of conventional cathodes for polymer electrolyte fuel cells (PEFCs), such as dissolution and migration of platinum-based catalysts and consumption of the carbon catalyst-support, a substantially novel gas-diffusion cathode has been proposed. The electrode was made of a porous oxide catalyst, which was coated on the inner and outer surfaces of a macro-porous titanium sheet substrate, using neither a platinum catalyst nor carbon catalyst-support. The suitability of this cathode for PEFCs, tested using a highly porous iridium oxide strongly coated on the macro-porous titanium sheet substrate, was confirmed by successful power generation. The gas-diffusion electrode functioned not only as the cathode but also as an anode of a PEFC.