CARBON-BASED FOAM NANOCOMPOSITE HYDROGEN STORAGE MATERIAL

• US 20070292732A1
• Filed: 11/30/2006
• Published: 12/20/2007
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: BASF SE, Washington University In St Louis
• Original Assignee: Washington University In St Louis
• Inventors: Cao, Guozhong, Feaver, Aaron
• Granted Patent: US 7,816,413 B2
• Time in Patent Office: Days
• US Class Current: 429/421
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01B 3/0021 Carbon, e.g. active carbon, carbon nanotubes, fullerenes; Treatment thereof
• CPC Class Codes: C01B 32/00 Carbon; Compounds thereof C01B21/00, C01B23/00 take precedence; percarbonates C01B15/10; carbon black C09C1/48
• CPC Class Codes: F17C 11/005 for hydrogen
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04089 of gaseous reactants
• CPC Class Codes: H01M 8/04216 characterised by the choice for a specific material, e.g. carbon, hydride, absorbent
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A carbon-based foam composite including a carbon-based foam and a solid state hydrogen storage material, methods for making the carbon-based foam composite, and methods for using the carbon-based foam composite. Representative carbon-based foams include cryogels, aerogels, and xerogels. Representative solid state hydrogen storage materials include metal hydrides and chemical hydrides.

Claims

1. A composite, comprising a carbon-based foam and a solid state hydrogen storage material.

2. The composite of claim 1, wherein the carbon-based foam is selected from the group consisting of a cryogel, aerogel, and xerogel.

3. The composite of claim 1, wherein the solid state hydrogen storage material comprises a metal hydride.

4. The composite of claim 3, wherein the metal hydride is magnesium hydride.

5. The composite of claim 1, wherein the solid state hydrogen storage material comprises a chemical hydride.

6. The composite of claim 5, wherein the chemical hydride is ammonia borane.

7. The composite of claim 1, wherein the solid state hydrogen storage material is a hydrogen storage material.

8. The composite of claim 1 further comprising a catalyst.

9. The composite of claim 1 further comprising a sulfur-modified surface.

10. The composite of claim 1, wherein the surface area of the carbon-based foam is from about 20 m²/g to about 3000 m²/g.

11. A method for making a carbon cryogel, comprising:

(a) preparing a sol by mixing a catalyst and at least two components capable of forming an organic sol-gel in water;

(b) gelling the sol by heating at a temperature and for a time sufficient to provide a gel;

(c) drying the gel to provide a polymer foam;

(d) pyrolyzing the polymer foam to provide a carbon-based foam; and

(e) contacting the carbon-based foam with a solid state hydrogen storage material, wherein the solid state hydrogen storage material infiltrates the carbon-based foam to provide a carbon-based foam composite.

12. The method of claim 11, wherein the components capable of forming a sol-gel comprise resorcinol and formaldehyde.

13. The method of claim 12, wherein the molar ratio of resorcinol to catalyst is from about 10 to about 2000.

14. The method of claim 11, wherein gelling the sol comprises heating at a temperature and for a period of time sufficient to convert the sol to a crosslinked gel.

15. The method of claim 11, wherein gelling the sol comprises heating at about 90°

C. for from about 1 to about 7 days.

16. The method of claim 11, wherein pyrolyzing the polymer foam comprises heating at a temperature and for a time sufficient to provide a carbon-based foam.

17. The method of claim 16, wherein pyrolyzing the polymer foam comprises heating at about 1050°

C. for about 4 hours in a substantially oxygen-free environment.

18. The method of claim 11, further comprising heating the carbon-based foam at a temperature and for a time sufficient to provide an activated carbon-based foam.

19. The method of claim 18, wherein heating at a temperature and for a time sufficient to provide an activated carbon foam comprises heating at about 900°

C. under carbon dioxide.

20. The method of claim 11, wherein drying the gel comprises freeze drying, supercritically drying, or evaporative drying.

21. The method of claim 11, wherein the solid state hydrogen storage material for infiltrating the foam is in liquid form.

22. The method of claim 11, wherein the solid state hydrogen storage material is a metal hydride.

23. The method of claim 11, wherein the solid state hydrogen storage material is a chemical hydride.

24. A system, comprising:

(a) a hydrogen storage vessel, comprising a vessel and a carbon-based foam composite, wherein the carbon-based foam composite comprises a carbon-based foam and a solid state hydrogen storage material; and

(b) a fuel cell capable of converting hydrogen into energy, wherein the fuel cell is in gaseous communication with the vessel.

25. A method for lowering the temperature required for releasing hydrogen from a solid state hydrogen storage material, comprising contacting a carbon-based foam with a solid state hydrogen storage material having a first hydrogen release temperature, to provide a composite having a second hydrogen release temperature, where the second hydrogen release temperature is lower than the first hydrogen release temperature.