Chiral or achiral, mesoporous carbon

Patent metadata

Field	Value
Publication number	US-9440854-B2
Application number	US-201214115659-A
Country	US
Kind code	B2
Filing date	May 10, 2012
Priority date	Mar 31, 2011
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

A composition and a method for producing mesoporous carbon materials with a chiral or achiral organization. In the method, a polymerizable inorganic monomer is reacted in the presence of nanocrystalline cellulose to give a material of inorganic solid with cellulose nanocrystallites organized in a chiral nematic organization. The cellulose can be carbonized through thermal treatment under inert atmosphere (e.g., nitrogen or argon) and the silica may subsequently be removed using aqueous solutions of sodium hydroxide (NaOH) or hydrogen fluoride (HF) to give the stable mesoporous carbon materials that retain the chiral nematic structure of the cellulose. These materials may be obtained as free-standing films with very high surface area. Through control of the reaction conditions the pore-size distribution may be varied from predominantly microporous to predominantly mesoporous materials. These are the first materials to use cellulose as both the structural template and carbon source for a mesoporous carbon material. These are also the first carbon materials to combine mesoporosity with long-range chiral ordering. Possible applications for these materials include: charge storage devices (e.g. supercapacitors and anodes for Li-ion batteries), adsorbents, gas purifiers, light-weight nanocomposite materials, catalyst supports (e.g., for chiral transformations), gas storage, and as a hard-template to generate other materials, preferably with chiral structures.

First claim

The invention claimed is:

1. A process for producing a mesoporous carbon material comprising:
i) carbonising nanocrystalline cellulose (NCC) in an inorganic matrix, and
ii) removing the inorganic matrix from the carbonised NCC.

2. A process according to claim 1 , wherein said carbonising comprises pyrolysis of the NCC under an inert atmosphere at an elevated temperature.

3. A process according to claim 2 , wherein said inert atmosphere is nitrogen and said elevated temperature is 500° C. to 2000° C.

4. A process according to claim 3 , wherein said inorganic matrix is silica and ii) comprises heating in an aqueous alkali.

5. A process according to claim 4 , wherein said alkali is sodium hydroxide and said heating is at 20° C. to 100° C.

6. A process according to claim 5 , wherein said NCC in the inorganic matrix comprises said NCC in a chiral nematic arrangement and i) and ii) are carried out with maintenance of the chiral nematic arrangement of the NCC in the carbonised NCC.

7. A process according to claim 6 , further comprising: iii) recovering said carbonised NCC as a powder.

8. A process according to claim 4 , wherein said NCC in the inorganic matrix comprises said NCC in a chiral nematic arrangement and i) and ii) are carried out with maintenance of the chiral nematic arrangement of the NCC in the carbonised NCC.

9. A process according to claim 8 , further comprising: iii) recovering said carbonised NCC as a film.

10. A process according to claim 1 , wherein said inorganic matrix is silica and ii) comprises heating in an aqueous alkali.

11. A process according to claim 10 , wherein said alkali is sodium hydroxide and said heating is at 20° C. to 100° C.

12. A process according to claim 1 , wherein said NCC in the inorganic matrix comprises said NCC in a chiral nematic arrangement and i) and ii) are carried out with maintenance of the chiral nematic arrangement of the NCC in the carbonised NCC.

13. A process according to claim 1 , further comprising: iii) recovering said carbonised NCC as a film.

14. A process according to claim 1 , further comprising: iii) recovering said carbonised NCC as a powder.

Assignees

• Maclachlan Mark John
• Shopsowitz Kevin Eric
• Hamad Wadood Yasser
• Fpinnovations

Inventors

• Maclachlan Mark John
• Shopsowitz Kevin Eric
• Hamad Wadood Yasser

Classifications

• C01B32/05 Primary

  Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30 · CPC title

• C01P2006/12

  Surface area · CPC title

• C09K19/02

  characterised by optical, electrical or physical properties of the components, in general · CPC title

• C04B38/0022

  obtained by a chemical conversion or reaction other than those relating to the setting or hardening of cement-like material or to the formation of a sol or a gel, e.g. by carbonising or pyrolysing preformed cellular materials based on polymers, organo-metallic or organo-silicon precursors · CPC title

• C04B35/532

  containing a carbonisable binder · CPC title