Methods for preparation of concentrated graphene ink compositions and related composite materials

Patent metadata

Field	Value
Publication number	US-9902866-B2
Application number	US-201514756304-A
Country	US
Kind code	B2
Filing date	Aug 24, 2015
Priority date	Apr 22, 2011
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

A rapid, scalable methodology for graphene dispersion and concentration with a polymer-organic solvent medium, as can be utilized without centrifugation, to enhance graphene concentration.

First claim

We claim:

1. A method of preparing an inkjet printed graphene ink composition, said method comprising:
exfoliating a graphene source material with a medium comprising an organic solvent selected from ethanol and dimethylformamide, and an ethyl cellulose;
contacting at least a portion of said exfoliated graphene medium with an aqueous medium to concentrate exfoliated graphene and ethyl cellulose in a solid precursor composition comprising graphene and a said ethyl cellulose;
isolating said solid composition from said exfoliating and said aqueous media;
contacting said solid graphene-ethyl cellulose precursor composition with a hydrophobic fluid component, to provide a graphene ink composition;
inkjet printing said graphene ink composition on a substrate; and
photonic annealing said graphene ink composition.

2. The method of claim 1 wherein said hydrophobic fluid comprises a component selected from terpenes, terpine alcohols and combinations thereof.

3. The method of claim 1 wherein said hydrophobic fluid component comprises a terpineol and cyclohexanone.

4. The method of claim 1 wherein said graphene ink composition has a graphene concentration of greater than about 3 mg/mL.

5. The method of claim 4 wherein said graphene ink composition has a graphene concentration of about 20 mg/mL.

6. The method of claim 5 wherein said graphene ink has a solids content of about 4% w/v.

7. The method of claim 6 wherein said graphene ink composition has a viscosity of about 8-15 mPa·sec.

8. The method of claim 1 wherein said exfoliating comprises shear mixing said graphene source material and said medium.

9. A method of preparing an inkjet printed graphene ink composition, said method comprising:
exfoliating a graphene source material with a medium comprising an organic solvent selected from ethanol and dimethylformamide, and an ethyl cellulose to provide a precursor composition comprising graphene and a said ethyl cellulose;
isolating said precursor composition from said exfoliating and said aqueous media;
contacting said graphene-ethyl cellulose precursor composition with a hydrophobic fluid component, to provide a graphene ink composition comprising a graphene concentration greater than about 3 mg/mL;
inkjet printing said graphene ink composition on a substrate; and
photonic annealing said graphene ink composition.

10. The method of claim 9 wherein said hydrophobic fluid comprises a component selected from terpenes, terpine alcohols and combinations thereof.

11. The method of claim 9 wherein said hydrophobic fluid component comprises a terpineol and cyclohexanone.

12. The method of claim 9 wherein said graphene ink composition has a graphene ink concentration of about 20 mg/mL.

13. The method of claim 12 wherein said graphene ink has a solids content of about 4% w/v.

14. The method of claim 13 wherein said graphene ink composition has a viscosity of about 8-15 mPa·sec.

15. The method of claim 9 wherein said exfoliating comprises shear mixing said graphene source material and said medium.

16. A method of using photonic annealing to prepare a graphene ink composite, said method comprising:
exfoliating a graphene source material with a medium comprising an organic solvent selected from ethanol and dimethylformamide, and an ethyl cellulose to provide a precursor composition comprising graphene and a said ethyl cellulose;
isolating said precursor composition from said exfoliating and said aqueous media;
contacting said graphene-ethyl cellulose precursor composition with a hydrophobic fluid component, to provide a graphene ink composition comprising a solids content of about 4% w/v, a graphene concentration of about 20 mg/mL and a viscosity of about 8-about 15 mPa·sec;
inkjet printing said graphene ink composition on a substrate to provide a graphene-substrate composite; and
photonic annealing said graphene ink composition to provide a graphene ink composition comprising a decomposition product of a said ethyl cellulose.

17. The method of claim 16 wherein said hydrophobic fluid component comprises a terpineol and cyclohexanone.

18. The method of claim 16 wherein said precursor composition comprises about 50% wt. graphene and about 50% wt. a said ethyl cellulose.

Assignees

• Univ Northwestern
• Harvard College

Inventors

• Hersam Mark C
• Liang Yu Teng
• Secor Ethan B
• Prabhumirashi Pradyumna L
• Puntambekar Kanan P
• Geier Michael L
• Ahn Bok Y
• Lewis Jennifer A

Classifications

• C09D11/38 Primary

  characterised by non-macromolecular additives other than solvents, pigments or dyes · CPC title

• C01B32/19

  by exfoliation · CPC title

• H01B1/24

  the conductive material comprising carbon-silicon compounds, carbon or silicon · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C09D11/36 Primary

  based on non-aqueous solvents · CPC title