Composites formed using magnetizable material, a catalyst and an electron conductor

• US 5,817,221 A
• Filed: 02/05/1996
• Issued: 10/06/1998
• Est. Priority Date: 08/25/1994
• Status: Expired due to Term

• Current Assignee: Iowa State University Research Foundation Incorporated (Iowa State University)
• Original Assignee: University of Iowa Research Foundation
• Inventors: Leddy, Johna, Tinoco, Flavio, Amarasinghe, Sudath
• Primary Examiner(s): Bell, Bruce F.
• Application Number:
  US08/597,026
• Time in Patent Office: 974 Days
• Field of Search: 204/290 R, 204/291, 204/292, 204/293, 204/294, 429/40, 429/44, 429/218
• US Class Current: 204/290.06
• CPC Class Codes: B03C 1/01 by addition of magnetic adjuvants
• CPC Class Codes: B03C 1/025 High gradient magnetic separators
• CPC Class Codes: B03C 1/034 characterised by the matrix elements
• CPC Class Codes: B03C 1/035 Open gradient magnetic separators, i.e. separators in which the gap is unobstructed, characterised by the configuration of the gap
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C23C 24/08 by application of heat or pressure and heat C23C24/04 takes precedence
• CPC Class Codes: C23C 30/00 Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process C23C26/00, C23C28/00 take precedence
• CPC Class Codes: C23C 6/00 Coating by casting molten material on the substrate
• CPC Class Codes: C25B 11/00 Electrodes; Manufacture thereof not otherwise provided for
• CPC Class Codes: C25D 3/54 of metals not provided for in groups C25D3/04 - C25D3/50
• CPC Class Codes: G21F 9/12 by absorption; by adsorption; by ion-exchange
• CPC Class Codes: H01F 1/0027 Thick magnetic films forming thick magnetic films H01F41/16
• CPC Class Codes: H01F 1/0054 Coated nanoparticles, e.g. nanoparticles coated with organic surfactant
• CPC Class Codes: H01F 1/009 bidimensional, e.g. nanoscale period nanomagnet arrays H01F10/007 takes precedence
• CPC Class Codes: H01F 10/007 ultrathin or granular films H01F10/005 and H01F10/3227 take precedence; applying ultrathin or granular layers to substrates H01F41/301
• CPC Class Codes: H01F 41/24 from liquids
• CPC Class Codes: H01F 41/26 using electric currents , e.g. electroplating
• CPC Class Codes: H01F 41/301 for applying ultrathin or granular layers ultrathin or granular layers H01F10/007
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H01M 2300/0082 : Organic polymers
• CPC Class Codes: H01M 4/02 : Electrodes composed of, or comprising, active material
• CPC Class Codes: H01M 4/86 : Inert electrodes with catalytic activity, e.g. for fuel cells
• CPC Class Codes: H01M 4/8605 : Porous electrodes
• CPC Class Codes: H01M 4/8857 : Casting, e.g. tape casting, vacuum slip casting
• CPC Class Codes: H01M 4/8882 : Heat treatment, e.g. drying, baking
• CPC Class Codes: H01M 4/9083 : on carbon or graphite
• CPC Class Codes: H01M 4/926 : on carbon or graphite
• CPC Class Codes: H01M 8/00 : Fuel cells; Manufacture thereof
• CPC Class Codes: H01M 8/1004 : characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: H01M 8/1009 : with one of the reactants being liquid, solid or liquid-charged H01M8/12 takes precedence
• CPC Class Codes: H01M 8/249 : comprising two or more groupings of fuel cells, e.g. modular assemblies
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

Magnetic composites exhibit distinct flux properties due to gradient interfaces. The composites can be used to improve fuel cells and batteries and effect transport and separation of different species of materials, for example, transition metal species such as lanthanides and actinides. A variety of devices can be made utilizing the composites including a separator, an electrode for channeling flux of magnetic species, an electrode for effecting electrolysis of magnetic species, a system for channeling electrolyte species, a system for separating particles with different magnetic susceptibilities, improved fuel cells, batteries, and oxygen concentrators. Some composites can be used to make a separator for distinguishing between two species of materials and a flux switch to regulate the flow of a chemical species. Some composites can control chemical species transport and distribution. Other composites enable ambient pressure fuel cells having enhanced performance and reduced weight to be produced. Still other composites enable rechargeable batteries to be made that have longer secondary cycle life and improved output power. Methods involving these composites provide distinct ways for these composites to be utilized.

Claims

1. A device comprising:

an electrode having a surface; and

a magnetic composite material disposed on said surface, said magnetic composite comprising carbon particles in association with a catalyst.

2. The device of claim 1, wherein said catalyst is platinum.

3. The device of claim 1, wherein said magnetic composite material further comprises particles comprising iron(III) oxide or magnetite.

4. The device of claim 3, wherein said particles comprising iron(III) oxide or magnetite are non-coated.

5. The device of claim 4, wherein said particles comprising iron(III) oxide or magnetite are aged prior to use.

6. The device of claim 3, wherein said carbon particles in association with a catalyst comprise from about 10% to about 50% by weight of said magnetic composite material.

7. The device of claim 3, wherein said particles comprising iron(III) oxide or magnetite comprise non-coated iron(III) oxide, and said catalyst comprises platinum, said platinum comprising from about 10% to about 40% by weight of said carbon particles in association with a catalyst.

8. The device of claim 1, wherein said magnetic composite material comprises about 10% by weight of particles comprising iron(III) oxide or magnetite, from about 10% to about 50% by weight of carbon particles in association with a catalyst, and an ion exchange polymer.

9. An electrode, comprising:

a conductor; and

a magnetic composite in surface contact with said conductor, said magnetic composite comprising iron(III) oxide or magnetite.

10. A device, comprising:

an electrode having a surface; and

at least one pillared magnetic structure on said surface.

11. The device as claimed in claim 10, wherein said at least one pillared magnetic structure comprises microscopic pillars.

12. The device as claimed in claim 10, wherein said at least one pillared magnetic structure comprises microscopic pillars formed by casting particles comprising iron(III) oxide or magnetite on said surface and arranging said electrode in an external magnetic field.

13. An electrode, comprising:

a conductor; and

a magnetic composite in surface contact with said conductor, said magnetic composite comprising an ion exchange polymer, a magnetic material, and carbon particles with a catalyst coated thereon.

14. The electrode as claimed in claim 13, wherein said catalyst comprises platinum, and said magnetic material comprises a plurality of magnetic beads, said magnetic beads encapsulated within a coating material.

15. The electrode of claim 14, wherein said coating material is chemically inert.

16. The electrode of claim 14, wherein said coating material comprises polymers, silanes, thiols, silica, or glass.

17. A device comprising:

a conductor having a surface; and

a magnetic composite material disposed on said surface, said magnetic composite comprising a catalyst.

18. The device as claimed in claim 17, wherein said catalyst comprises platinum.

19. The device as claimed in claim 18, wherein said magnetic composite further comprises carbon particles.

20. A device comprising:

an electrode having a surface; and

a magnetic composite disposed on said surface, said magnetic composite comprising platinum particles.

21. The device of claim 20, wherein said platinum particles serve as a catalyst, an electron conductor, or both catalyst and electron conductor.