Membrane-electrode assembly for a direct methanol fuel cell

Abstract

A direct methanol fuel cell (DMFC) contains a membrane electrode assembly (MEA) including an anode porous electrode structure which can operate on a liquid or vapor methanol/water feed in the absence of a liquid electrolyte such as sulfuric acid, a proton-exchange membrane electrolyte, and a porous gas-diffusion cathode. The anode porous electrode structure includes a three-dimensional reduced (Pt--Ru)O.sub.x catalyst particle-ionomer composite structure, whereby the ionomer coats the individual particles and provides a mechanism for continuous proton transport throughout the composite structure, eliminating the need for a liquid acidic electrolyte. The partially reduced (Pt--Ru)O.sub.x particles are individually ionomer coated prior to anode fabrication. The anode porous electrode structure is subsequently bonded to one side of a thin sheet of a solid proton-conducting ionomer membrane and a cathode structure bonded to the opposite side of the membrane, to form a MEA. Insertion of the MEA into appropriate hardware results in fuel cell fabrication.

Dependencies are inferred from the claim text.