Carbon-based foam nanocomposite hydrogen storage material
View Patent ↗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.
1. A method for making a carbon-based foam composite comprising a carbon-based foam and a solid state hydrogen storage material, 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 said sol by heating at a temperature and for a time sufficient to provide a gel;
(c) drying said gel to provide a polymer foam;
(d) pyrolyzing said polymer foam to provide a carbon-based foam; and
(e) contacting said carbon-based foam with a solid state hydrogen storage material wherein said solid state hydrogen storage material infiltrates said carbon-based foam to provide a carbon-based foam composite.
2. The method of claim 1 , wherein said components capable of forming a sol-gel comprise resorcinol and formaldehyde.
3. The method of claim 2 , wherein the molar ratio of resorcinol to catalyst is from about 10 to about 2000.
4. The method of claim 1 , wherein gelling said sol comprises heating at a temperature and for a period of time sufficient to convert said sol to a crosslinked gel.
5. The method of claim 1 , wherein gelling said sol comprises heating at about 90° C. for from about 1 to about 7 days.
6. The method of claim 1 , wherein pyrolyzing said polymer foam comprises heating at a temperature and for a time sufficient to provide a carbon-based foam.
7. The method of claim 6 , wherein pyrolyzing said polymer foam comprises heating at about 1050° C. for about 4 hours in a substantially oxygen-free environment.
8. The method of claim 1 , further comprising heating said carbon-based foam at a temperature and for a time sufficient to provide an activated carbon-based foam.
9. The method of claim 8 , wherein heating at a temperature and for a time sufficient to provide an activated carbon-based foam comprises heating at about 900° C. under carbon dioxide.
10. The method of claim 1 , wherein drying said gel comprises freeze drying.
11. The method of claim 1 , wherein said solid state hydrogen storage material for infiltrating said foam is in liquid form.
12. The method of claim 1 , wherein said solid state hydrogen storage material is a metal hydride.
13. The method of claim 1 , wherein said solid state hydrogen storage material is a chemical hydride.
14. The method of claim 1 , wherein said solid state hydrogen storage material comprises Mg 2 FeH 6 , Na 3 AlH 6 , NaAlH 4 , MnNi 5 H 6 , TiCr 1.8 H 1.7 , Mg 2 NiH4, CaNi 5 H 5 , TiFeH, MgH 2 , LaNi 5.5 Al 1.5 H 5 , or LaNi 4 AlH 5 .
15. The method of claim 1 , wherein said solid state hydrogen storage material comprises ammonia borane, LiAlH 4 , LiBH 4 , NaAlH 4 , or NaBH 4 .
16. The method of claim 1 wherein said solid state hydrogen storage material comprises magnesium hydride or ammonia borane.
17. The method of claim 1 , wherein drying said gel comprises supercritically drying.
18. The method of claim 1 , wherein drying said gel comprises evaporative drying.