Ionic liquid functionalized reduced graphite oxide / TiO2 nanocomposite for conversion of CO2 to CH4

Patent metadata

Field	Value
Publication number	US-9545625-B2
Application number	US-201314076764-A
Country	US
Kind code	B2
Filing date	Nov 11, 2013
Priority date	Nov 9, 2012
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

An ionic liquid functionalized reduced graphite oxide (IL-RGO)/TiO 2 nanocomposite was synthesized and used to reduce CO 2 to a hydrocarbon in the presence of H 2 O vapor.

First claim

What is claimed is:

1. A photocatalytic nanocomposite comprising:
a reduced graphite oxide;
a photocatalytic metal oxide in nanoparticle form; and
an ionic moiety attached to the reduced graphite oxide;
wherein the photocatalytic metal oxide in nanoparticle form is dispersed in the reduced graphite oxide.

2. The photocatalytic nanocomposite of claim 1 , wherein the ionic moiety comprises R 1 R 2 R 3 and wherein R 1 is NH, R 2 is alkylene, and R 3 is a cationic group.

3. The photocatalytic nanocomposite of claim 2 , wherein R 2 is C 1 to C 5 alkylene, and R 3 is an imidazole ring protonated or substituted at a nitrogen atom.

4. The photocatalytic nanocomposite of claim 3 , wherein R 2 is propylene, and R 3 is an alkyl-substituted imidazole ring.

5. The photocatalytic nanocomposite of claim 1 , wherein the reduced graphite oxide is an ionic liquid functionalized reduced graphite oxide formed by attaching a NH 2 -terminated ionic liquid to the reduced graphite oxide.

6. The photocatalytic nanocomposite of claim 1 , wherein the photocatalytic metal oxide is TiO 2 .

7. The photocatalytic nanocomposite of claim 6 , wherein the TiO 2 is in the form of rutile and anatase.

8. The photocatalytic nanocomposite of claim 1 , wherein the reduced graphite oxide is a powder.

9. A method of making a photocatalytic nanocomposite comprising:
oxidizing graphite to form a reduced graphite oxide;
attaching an ionic moiety to the reduced graphite oxide; and
mixing the reduced graphite oxide with a photocatalytic metal oxide in nanoparticle form to form the photocatalytic nanocomposite.

10. The method of claim 9 , further comprising the step of functionalizing the reduced graphite oxide with a NH 2 -terminated ionic liquid to form an ionic liquid functionalized reduced graphite oxide before the step of mixing.

11. The method of claim 10 , wherein the NH 2 -terminated ionic liquid is an imidazole.

12. The method of claim 10 , wherein the NH 2 -terminated ionic liquid is a 1-butyl-3-methylimidazolium-based ionic liquid.

13. The method of claim 10 , wherein the NH 2 -terminated ionic liquid is a 1-butyl-3-methylimidazolium chloride.

14. A method of CO 2 photoreduction comprising:
contacting reactants of CO 2 and H 2 O over a photocatalytic nanocomposite according to claim 1 ;
reacting the CO 2 and H 2 O over the photocatalytic nanocomposite to produce products including CH 4 .

15. The method of claim 14 , wherein the products are substantially free of CO gas.

16. The method of claim 14 , wherein the CH 4 has a production rate in excess of 10 μmol/g catalyst-hr.

17. The method of claim 14 , wherein the CH 4 has a production rate in excess of 250 μmol/g catalyst-hr.

18. The method of claim 9 , wherein the photocatalytic metal oxide is TiO 2 .

Assignees

• Andino Jean
• Gao Tingting
• Univ Arizona State

Inventors

• Andino Jean
• Gao Tingting

Classifications

• B01J2235/10

  Infrared [IR] · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/45

  Nanoparticles · CPC title

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title