US 2008/0305250 A1 · Fabrication Methods for Catalyst Coated Membranes

Abstract

Fabrication methods for catalyst coated membranes are provided. The methods include exposing a micro-porous membrane to a catalyst dispersing solution to form a catalyst containing micro-porous membrane. The methods also include exposing the catalyst containing micro-porous membrane to a resin dispersing solution to form a catalyst layer and placing a proton exchange membrane between two of the catalyst layers with a laminating process to form the catalyst coated membrane. The fabrication methods provide filling process to uniformly fill the catalysts and resin throughout the pores of the micro-porous membranes in the catalyst layers. These micro-porous membranes are hydrophobic and easily discharge water when necessary. Therefore, membrane electrode assemblies with catalyst coated membranes fabricated using the provided methods are stable and perform well during fuel cell operation.

Claims20

Dependent claims

A method for the fabrication of catalyst coated membranes, comprising the steps of:

first exposing a micro-porous membrane to a catalyst dispersing solution to form a catalyst containing micro-porous membrane;
second exposing said catalyst containing micro-porous membrane to a resin dispersing solution to form a catalyst layer;
and
placing a proton exchange membrane between two of said catalyst layers to form said catalyst coated membrane.

1 more element

A method for the fabrication of catalyst coated membranes, comprising the steps of:

coating a micro-porous membrane with a catalyst dispersing solution to form a catalyst containing micro-porous membrane under a vacuum of 0.01 mPa to 0.1 mPa;
drying said catalyst containing micro-porous membrane at 30° C. to 150° C.;
coating said dried catalyst containing micro-porous membrane with a resin dispersing solution to form a catalyst layer under a vacuum of 0.01 mPa to 0.1 mPa;
drying said catalyst layer at 25° C. to 200° C.;
and
placing a proton exchange membrane between two of said catalyst layers to form said catalyst coated membrane;
and wherein
the thickness of said micro-porous membrane is 3 micrometers to 20 micrometers;
the diameter of said micro-porous is 0.5 to 2.0 micrometers;
the porosity of said micro-porous membrane is 70% to 95%;
said catalyst dispersing solution comprising a catalyst, alcohol, and water;
the weight ratio of said catalyst:alcohol:water is 1:10 to 500:0 to 50;
said catalyst is selected one or more chemicals with catalytic properties selected from the group consisting of:
nano-platinum, nano-gold, nano-ruthenium, nano-silver, nano-cobalt, nano-platinum-ruthenium alloys, nano-platinum-cobalt alloy, nano-platinum supported on carbon, nano-gold supported on carbon, nano-ruthenium supported on carbon, nano-silver supported on carbon, nano-cobalt supported on carbon, nano-platinum-ruthenium alloys supported on carbon, and nano-platinum-cobalt alloy supported on carbon;
the quantity of catalyst in said catalyst containing micro-porous membrane is 0.1 mg/cm2 to 0 mg/cm2;
said resin dispersing solution comprising of one or more resins and one or more solvent;
the concentration of said resins in said resin dispersing solution is 0.01 wt. % to 3 wt. %;
the concentration of resins in said micro-porous membrane is 0.03 mg/cm2 to 20 mg/cm2;
and
said micro-porous membrane is supported by a support selected from the group consisting of:
PET felts, polypropylene felts, polyethylene nets or PET non-woven fabrics and said support is removed prior to said placing step.

18 more elements

Dependencies are inferred from the claim text.

Fabrication Methods for Catalyst Coated Membranes

Life of this patent

Fabrication Methods for Catalyst Coated Membranes

Life of this patent

Abstract

Claims20