Method of imprinting catalytically active particles on membrane

• US 5,415,888 A
• Filed: 04/26/1993
• Issued: 05/16/1995
• Est. Priority Date: 04/26/1993
• Status: Expired due to Term

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.), H Power Corporation (Plug Power Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Banerjee, Shoibal, Bloomfield, David P., Grot, Walther G.
• Primary Examiner(s): LUSIGNAN, MICHAEL R
• Application Number:
  US08/051,823
• Time in Patent Office: 750 Days
• Field of Search: 252/514, 427/244, 427/125, 427/282, 427/421, 427/429, 429/33, 429/42
• US Class Current: 427/125
• CPC Class Codes: C25B 9/23 comprising ion-exchange membranes in or on which electrode material is embedded
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A membrane and electrode structure is formed by applying ink of catalytically active particles on the surface of the membrane. The electrode ink comprises:

(a) catalytically active particles;

(b) a hydrocarbon having at least one ether, epoxy or ketone linkage and an alcohol group, preferably 1 methoxy 2 propanol; and

(c) optionally, perfluorinated sulfonyl fluoride polymer or perfluorinated sulfonic acid polymer.

Claims

1. A method for making a membrane and electrode, structure comprising contacting at least one surface of an ion exchange membrane with an electrode ink comprising:

(a) catalytically active particles; and

(b) a hydrocarbon having one or more ether, epoxy or ketone linkages and an alcohol group.

2. The method of claim 1 in which the hydrocarbon is 1-methoxy 2-propanol.

3. The method of claim 1 in which the hydrocarbon is nonsolid at the processing temperatures of the structure.

4. The method of claim 1 in which the hydrocarbon is selected from the group of 1-ethoxy-2-propanol;

1-methoxy 2-methyl 2-propanol;

1-isopropoxy 2-propanol;

1-propoxy 2-propanol;

2-phenoxy 1-propanol;

2-ethoxy 1-propanol;

2,3-ethoxy 1-propanol;

2-methoxy 1-propanol;

1-butoxy 2-propanol;

or mixtures thereof.

5. The method of claim 1 in which the electrode ink further comprises a sulfonyl fluoride polymer.

6. The method of claim 5 in which the polymer is hydrolyzed.

7. The method of claim 5 in which the polymer is unhydrolyzed.

8. The method of claim 5 in which the polymer is in a solution, suspension or dispersion of alcohol and water.

9. The method of claim 1 in which the catalytically active particle comprises a platinum group metal.

10. The method of claim 8 in which the platinum group metal is on a carbon support.

11. The method of claim 1 in which the catalytically active particles are present at about 5-40 weight percent.

12. The method of claim 1 in which the hydrocarbon is present at about 50-95 weight percent.

13. The method of claim 1 wherein the electrode ink is sprayed on the surface of the membrane.

14. The method of claim 1 wherein the electrode ink is brushed on the surface of the membrane.

15. The method of claim 1 wherein the electrode ink is screen printed on the surface of the membrane.

16. The method of claim 1 wherein the electrode ink is coated on the surface of the membrane in a plurality of applications.

17. The method of claim 1 further comprising bonding the electrode ink to the surface of the membrane under pressure at temperatures of up to about 300°

C.

18. The method of claim 1 in which the electrode ink is applied to the surface of a substrate and then the electrode ink layer is transferred from the substrate to the surface of the membrane.

19. The method of claim 18 in which the electrode ink layer is transferred to the surface of the membrane by hot pressing.

20. The method of claim 1 wherein the electrode ink is printed on the surface of the membrane in a plurality of applications.