Sulfonated Amorphous Carbon, Process for Producing the Same and Use Thereof

• US 20080227996A1
• Filed: 09/08/2004
• Published: 09/18/2008
• Est. Priority Date: 09/16/2003
• Status: Active Grant

• Current Assignee: Tokyo Institute of Technology (National University Corporation Tokyo Institute of Technology)
• Original Assignee: The Circle for the Promotion of Science and Engineering
• Inventors: Domen, Kazunari, Hara, Michikazu
• Granted Patent: US 8,709,273 B2
• Time in Patent Office: Days
• US Class Current: 558/44
• CPC Class Codes: B01J 2231/40 Substitution reactions at carbon centres, e.g. C-C or C-X, i.e. carbon-hetero atom, cross-coupling, C-H activation or ring-opening reactions
• CPC Class Codes: B01J 31/0225 comprising sulfonic acid groups or the corresponding salts
• CPC Class Codes: B01J 31/06 containing polymers organometallic polymers B01J31/123; polymer-bound organometallic complexes B01J31/165; coordination polymers B01J31/1691
• CPC Class Codes: C01B 32/05 Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
• CPC Class Codes: C07C 309/38 formed by at least three rings
• CPC Class Codes: H01B 1/122 Ionic conductors
• CPC Class Codes: H01M 8/1016 characterised by the electrolyte material H01M8/12 takes precedence
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

An amorphous carbon having sulfonate group introduced therein is provided which is characterized in that chemical shifts of a condensed aromatic carbon 6-membered ring and a condensed aromatic carbon 6-membered ring having sulfonate group bonded thereto are detected in a ¹³C nuclear magnetic resonance spectrum and that at least a diffraction peak of carbon (002) face whose half-value width (2θ) is in the range of 5 to 30° is detected in powder X-ray diffractometry, and which exhibits proton conductivity. This sulfonated amorphous carbon is very useful as a proton conductor material or solid acid catalyst because it excels in proton conductivity, acid catalytic activity, thermal stability and chemical stability and can be produced at low cost.

Claims

1. A proton conductor material comprising an amorphous carbon having sulfonate group introduced therein.

2. The proton conductor material according to claim 1, wherein the amorphous carbon having sulfonate group introduced therein has a proton conductivity of 0.01 to 0.2 Scm⁻

1 as measured by alternating current impedance method under the conditions of a temperature of 80°

C. and a humidity of 100%.

3. The proton conductor material according to claim 1 or 2, wherein the amorphous carbon having sulfonate group introduced therein has a sulfur content of 0.3 to 15 atm %.

4. The proton conductor material according to claim 1, wherein the amorphous carbon having sulfonate group introduced therein is produced by heat treatment of an aromatic hydrocarbon in concentrated sulfuric acid or fuming sulfuric acid.

5. The proton conductor material according to claim 4, wherein the heat treatment is performed at a temperature of 100°

C. to 350°

C.

6. The proton conductor material according to claim 4 or 5, wherein the aromatic hydrocarbon is at least one substance selected from the group consisting of benzene, naphthalene, anthracene, peryrene and coronene.

7. An amorphous carbon having sulfonate group introduced therein characterized in that chemical shifts of a condensed aromatic carbon 6-membered ring and a condensed aromatic carbon 6-membered ring having sulfonate group bonded thereto are detected in a ¹³C nuclear magnetic resonance spectrum and that at least a diffraction peak of carbon (002) face whose half-value width (2θ

) is in the range of 5 to 30 is detected in powder X-ray diffractometry, the amorphous carbon having sulfonate group introduced therein exhibiting proton conductivity.

8. The amorphous carbon having sulfonate group introduced therein according to claim 7, wherein only a diffraction peak of carbon (002) face is detected in powder X-ray diffractometry.

9. The amorphous carbon having sulfonate group introduced therein according to claim 7 or 8, the amorphous carbon having sulfonate group introduced therein has a sulfonate density of 0.5 to 8 mmol/g.

10. The amorphous carbon having sulfonate group introduced therein according to claim 7 or 8, the amorphous carbon having sulfonate group introduced therein has a sulfonate density of 1.6 to 8 mmol/g.

11. The amorphous carbon having sulfonate group introduced therein according to claim 7 or 8, the amorphous carbon having sulfonate group introduced therein has a sulfonate density of 3 to 8 mmol/g.

12. The amorphous carbon having sulfonate group introduced therein according to claim 7, wherein the amorphous carbon having sulfonate group introduced therein has a proton conductivity of 0.01 to 0.2 Scm⁻

1 as measured by alternating current impedance method under the conditions of a temperature of 80°

C. and a humidity of 100%.

13. A process for producing an amorphous carbon having sulfonate group introduced therein as recited in claim 7, comprising a step of performing heat treatment of an organic compound in concentrated sulfuric acid or fuming sulfuric acid.

14. The process for producing an amorphous carbon having sulfonate group introduced therein according to claim 13, wherein the step of performing heat treatment of an organic compound in concentrated sulfuric acid or fuming sulfuric acid is conducted in a stream of an inert gas or dry air.

15. The process for producing an amorphous carbon having sulfonate group introduced therein according to claim 13, further comprising, after the step of performing heat treatment of an organic compound in concentrated sulfuric acid or fuming sulfuric acid, a step of heating the heat-treated product under vacuum evacuation.