METHOD FOR THE ELECTROCHEMICAL DEPOSITION OF CATALYST PARTICLES ONTO CARBON FIBRE- CONTAINING SUBSTRATES AND APPARATUS THEREFOR

The present invention describes a method and an apparatus for the electrochemical deposition of fine catalyst particles onto carbon fibre-containing substrates which have a compensating layer ("microlayer"). The method comprises the preparation of a precursor suspension containing ionomer, carbon black and metal ions. This suspension is applied to the substrate and then dried. The deposition of the catalyst particles onto the carbon fibre-containing substrate is effected by a pulsed electrochemical method in an aqueous electrolyte. The noble metal-containing catalyst particles produced by the method have particle sizes in the nanometer range. The catalyst-coated substrates are used for the production of electrodes, gas diffusion electrodes and membrane electrode units for electrochemical devices, such as fuel cells (membrane fuel cells, PEMFC, DMFC, etc.), electrolysers or electrochemical sensors.