REDUCED GRAPHENE OXIDE FILM

• US 20090235721A1
• Filed: 02/06/2009
• Published: 09/24/2009
• Est. Priority Date: 03/20/2008
• Status: Active Grant

• Current Assignee: The Government Of The United States As Represented By The Secretary Of The Navy
• Original Assignee: The Government Of The United States Of America, As Represented By The Secretary Of The Navy
• Inventors: Robinson, Jeremy T., Snow, Eric S.
• Granted Patent: US 8,182,917 B2
• Time in Patent Office: Days
• US Class Current: 73/31.50
• CPC Class Codes: B05D 1/005 Spin coating
• CPC Class Codes: B32B 2037/243 Coating
• CPC Class Codes: B32B 2309/105 Thickness
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01G 3/16 measuring variations of frequency of oscillations of the body
• CPC Class Codes: G01N 5/00 Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid G01N9/00 takes precedence ; weighing per se G01G
• CPC Class Codes: H01H 1/0036 Switches making use of microelectromechanical systems [MEMS] for electromagnetic relays H01H50/005; for electrostatic relays H01H59/0009
• CPC Class Codes: H01H 2203/012 Microprotrusions
• CPC Class Codes: H01H 59/0009 making use of micromechanics
• CPC Class Codes: Y10T 428/24562 Interlaminar spaces
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

Spin coating a mixture of graphene oxide platelets, water, and an organic solvent by placing a drop of the mixture on a spinning substrate while blowing a drying gas onto the substrate and allowing the water and the organic solvent on the substrate to evaporate; and repeating the spin coating one or more times to form a graphene oxide film in contact with the substrate. An about 1-100 nm thick film of overlapping platelets of reduced graphene oxide.

Claims

1. A method comprising:

providing a mixture of graphene oxide platelets, water, and an organic solvent;

spin coating the mixture by placing a drop of the mixture on a spinning substrate while blowing a drying gas onto the substrate and allowing the water and the organic solvent on the substrate to evaporate; and

repeating the spin coating one or more times to form a graphene oxide film in contact with the substrate.

2. The method of claim 1, wherein the organic solvent is methanol.

3. The method of claim 1, wherein each spin coating produces a sub-monolayer of graphene oxide on the substrate.

4. The method of claim 1, wherein the spin coating is repeated up to 300 times.

5. The method of claim 1, wherein the substrate is spun from about 2000 to about 6000 RPM.

6. The method of claim 1, wherein the drop of the mixture is up to about 100 μ

L in volume.

7. The method of claim 1, further comprising:

at least partially reducing the graphene oxide film.

8. The method of claim 7, wherein the graphene oxide film is reduced with hydrazine hydrate vapor.

9. The method of claim 7, wherein the graphene oxide film is reduced by annealing in an inert gas or hydrogen.

10. The film made by the method of claim 7.

11. The method of claim 7 further comprising:

releasing the graphene oxide film from the substrate; and

placing the released film on a second substrate.

12. The method of claim 11, wherein the graphene oxide film is released with a sodium hydroxide solution or potassium hydroxide solution.

13. A film comprising overlapping platelets of reduced graphene oxide;

wherein the film is from about 1 nm to about 100 nm thick.

14. The film of claim 13, wherein the film is in electrical contact with two electrodes.

15. A sensor comprising:

the film and the electrodes of claim 14;

an intake that contacts a fluid sample to the film; and

an electrical meter in contact with the electrodes.

16. The film of claim 13, wherein the film is in contact with a contoured substrate such that portions of the film are suspended above the substrate.

17. A mass sensor comprising:

the film and contoured substrate of claim 16; and

a device that measures vibrations of the suspended film.

18. The mass sensor of claim 17, wherein the device is a laser interferometer or a capacitance meter.

19. A device comprising:

the film and contoured substrate of claim 16;

wherein the space between the suspended film and the contoured substrate is a microfluidic channel.

20. An optical modulator comprising:

the film and contoured substrate of claim 16;

two electrodes in electrical contact with the film;

a voltage source attached to the electrodes that applies a voltage that causes a portion of the suspended film to contact the substrate.

21. A switch comprising:

the film and contoured substrate of claim 16;

two electrodes in electrical contact with the film;

a third electrode on the substrate below the suspended portion of the film.

a voltage source attached to the electrodes in electrical contact with the film that applies a voltage that causes a portion of the suspended film to contact the third electrode.

22. The film of claim 13, wherein the film has a Young'"'"'s modulus of at least about 100 GPa.