Membranes for use in electrochemical sensors and associated devices

Patent metadata

Field	Value
Publication number	US-10775339-B2
Application number	US-201514946485-A
Country	US
Kind code	B2
Filing date	Nov 19, 2015
Priority date	Nov 26, 2014
Publication date	Sep 15, 2020
Grant date	Sep 15, 2020

Abstract

A membrane is provided, as well as membrane electrode assemblies and sensors utilizing the membrane of the present technology. The membrane includes a membrane material with a top surface and a bottom surface; and a protonic ionic liquid disposed at least between the top surface and the bottom surface of the membrane material where the protonic ionic liquid is of Formula I.

First claim

What is claimed is:

1. A membrane electrode assembly comprising
an anode;
a cathode comprising an oxygen reduction catalyst; and
an ion exchange membrane comprising:
a membrane material with a top surface and a bottom surface and comprising a glass fiber membrane material; and
a protonic ionic liquid disposed at least between the top surface and the bottom surface of the membrane material;
wherein the protonic ionic liquid is of Formula I:

where R 1 , R 2 , and R 3 are each independently H or a substituted or unsubstituted alkyl or cycloalkyl group, or where R 1 and R 2 taken together are a C 2 -C 4 alkylene group; and
X − is a sulfate, bisulfate, sulfonate, halide, carboxylate, phosphate, phosphonate, dicyanamide anion, perfluoroalkylsulfonate, perfluoroalkylsulfonamide anion, or bis(perfluoroalkylsulfonyl)imide anion; and
wherein the glass fiber membrane material comprises glass fibers and at least one structural unit according to Formula IIa:

wherein
R 4 and R 5 are each independently H or a substituted or unsubstituted alkyl or cycloalkyl group, or where R 4 and R 5 taken together are a C 4 -C 6 alkylene group;
R 6 is a substituted or unsubstituted alkylene or cycloalkylene group;
R 7 is hydroxyl, alkoxy, aryloxy, or G 2 ;
R 8 is hydroxyl, alkoxy, aryloxy, or G 3 ;
G 1 , G 2 , and G 3 are each independently an oxygen atom of the glass fiber, where G 1 , G 2 , and G 3 are not the same oxygen atom; and
Y − is a sulfate, bisulfate, sulfonate, halide, carboxylate, phosphate, phosphonate, dicyanamide anion, perfluoroalkylsulfonate, perfluoroalkylsulfonamide anion, or bis(perfluoroalkylsulfonyl)imides.

2. The membrane electrode assembly of claim 1 , wherein
R 1 , R 2 , and R 3 are each independently H or an unsubstituted alkyl group.

3. The membrane electrode assembly of claim 1 , wherein
R 1 , R 2 , and R 3 are each independently H, methyl, ethyl, n-propyl, or i-propyl.

4. The membrane electrode assembly of claim 1 , wherein
X − is triflate, nonafluorobutylsulfonate, or a perfluoroalkylsulfonate, or X − is a sulfonate functional group of the membrane material.

5. The membrane electrode assembly of claim 1 , wherein the membrane material further comprises one or more of an expanded polytetrafluoroethylene, a polypropylene, a cellulose membrane material, a polystyrene, a polyamide, a polybenzimidazole, or a tetrafluoroethylene-perfluoroalkylvinylether,
wherein the expanded PTFE, polypropylene, polystyrene, polyamide, polybenzimidazole, and/or tetrafluoroethylene-perfluoroalkylvinylether optionally includes sulfonic acid groups, carboxylate groups, phosphate groups, phosphonate groups, or combinations of any two or more thereof.

6. The membrane electrode assembly of claim 1 , wherein the glass fiber membrane material further comprises at least one structural unit according to Formula IIb:

7. The membrane electrode assembly of claim 1 , wherein
R 4 and R 5 are each independently H or an unsubstituted alkyl or aryl group; and
R 6 is an unsubstituted alkylene group.

8. The membrane electrode assembly of claim 1 , wherein
R 4 and R 5 are each independently H or an unsubstituted alkyl group;
R 6 is an unsubstituted alkylene group;
R 7 is alkoxy or G 2 ; and
R 8 is alkoxy or G 3 .

9. The membrane electrode assembly of claim 1 , wherein the glass fiber membrane material comprises a plurality of structural units according to Formula IIa.

10. The membrane electrode assembly of claim 6 , wherein the glass fiber membrane material comprises a plurality of structural units according to Formula IIb.

11. The membrane electrode assembly of claim 1 , wherein a thickness defined by the top surface and the bottom surface of the membrane material is from about 10 μm to about 400 μm.

12. The membrane electrode assembly of claim 1 , wherein
the membrane material further comprises a tetrafluoroethylene-perfluoroalkylvinylether copolymer wherein the copolymer comprises sulfonic acid groups.

13. The membrane electrode assembly of claim 1 , wherein the ion exchange membrane has from about 20 wt % to about 90 wt % of the protonic ionic liquid.

14. The membrane electrode assembly of claim 1 , wherein the ion exchange membrane further comprises an ion conducting material not of Formula I.

15. The membrane electrode assembly of claim 1 , wherein the ion exchange membrane does not comprise a polymer.

16. An electrochemical carbon monoxide sensor for use in a gas or fire detector,
the sensor comprising a first sidewall; a second sidewall; a top wall; and a bottom wall; the first sidewall, the second sidewall, the top wall and the bottom wall defining a containment region and containing therein a membrane electrode assembly of claim 1 ;
wherein:
the top wall comprises a gaseous diffusion aperture;
the ion exchange membrane permits ion transport between the anode and the cathode; and
the ion exchange membrane prevents electron conduction between the anode and the cathode.

17. The membrane electrode assembly of claim 1 , wherein the ion exchange membrane has from about 20 wt % to about 60 wt % of the protonic ionic liquid.

18. The membrane electrode assembly of claim 1 , wherein the ion exchange membrane is a proton conducting membrane.

19. The membrane electrode assembly of claim 17 , wherein the ion exchange membrane is a proton conducting membrane.

20. The membrane electrode assembly of claim 19 , wherein the ion exchange membrane does not comprise a polymer.

Assignees

• Gentex Corp

Inventors

• Nemes Joel C

Classifications

• C25B13/05

  based on inorganic materials · CPC title

• H01M8/0293

  Matrices for immobilising electrolyte solutions · CPC title

• C08J5/2256

  based on macromolecular compounds obtained by reactions other than those involving carbon-to-carbon bonds, e.g. obtained by polycondensation · CPC title

• Y02E60/50

  Fuel cells · CPC title

• G01N27/4045 Primary

  for gases other than oxygen · CPC title