PROCESSES FOR FORMING COMPOSITE STRUCTURES WITH A TWO-DIMENSIONAL MATERIAL USING A POROUS, NON-SACRIFICIAL SUPPORTING LAYER

• US 20150217219A1
• Filed: 01/29/2015
• Published: 08/06/2015
• Est. Priority Date: 01/31/2014
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: BEDWORTH, Peter V., SINTON, Steven W., SINSABAUGH, Steven Lloyd, CASEY, David Francis Jr., HEISE, Scott E., STOLTENBERG, Randall Mark, SWETT, Jacob Louis
• Granted Patent: US 10,500,546 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2323/39 Electrospinning
• CPC Class Codes: B01D 2325/24 Mechanical properties, e.g. strength
• CPC Class Codes: B01D 67/00046 by deposition by filtration through a support or base layer
• CPC Class Codes: B01D 67/002 from melts
• CPC Class Codes: B01D 67/003 by selective elimination of components, e.g. by leaching
• CPC Class Codes: B01D 67/0034 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01D 67/0037 by deposition from the gaseous phase, e.g. CVD, PVD
• CPC Class Codes: B01D 67/0053 by inducing porosity into non porous precursor membranes
• CPC Class Codes: B01D 67/0058 by selective elimination of components, e.g. by leaching
• CPC Class Codes: B01D 67/0062 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01D 67/0069 by deposition from the liquid phase, e.g. electrochemical deposition B01D67/0046 takes precedence
• CPC Class Codes: B01D 67/0072 by deposition from the gaseous phase, e.g. sputtering, CVD, PVD
• CPC Class Codes: B01D 69/02 characterised by their properties
• CPC Class Codes: B01D 69/10 Supported membranes; Membrane supports
• CPC Class Codes: B01D 69/1071 Woven, non-woven or net mesh
• CPC Class Codes: B01D 69/108 Inorganic support material
• CPC Class Codes: B01D 71/0211 Graphene or derivates thereof

Abstract

It can be difficult to remove atomically thin films, such as graphene, graphene-based material and other two-dimensional materials, from a growth substrate and then to transfer the thin films to a secondary substrate. Tearing and conformality issues can arise during the removal and transfer processes. Processes for forming a composite structure by manipulating a two-dimensional material, such as graphene or graphene-base material, can include: providing a two-dimensional material adhered to a growth substrate; depositing a supporting layer on the two-dimensional material while the two-dimensional material is adhered to the growth substrate; and releasing the two-dimensional material from the growth substrate, the two-dimensional material remaining in contact with the supporting layer following release of the two-dimensional material from the growth substrate.

Claims

1. A process comprising:

providing a two-dimensional material adhered to a growth substrate;

depositing a supporting layer on the two-dimensional material while the two-dimensional material is adhered to the growth substrate; and

releasing the two-dimensional material from the growth substrate, the two-dimensional material remaining in contact with the supporting layer following release of the two-dimensional material from the growth substrate.

2. The process of claim 1, wherein releasing the two-dimensional material from the growth substrate comprises etching the growth substrate.

3. The process of claim 1, wherein the two-dimensional material comprises a graphene or graphene-based film, a transition metal dichalcogenide, α

-boron nitride, silicene, germanene or a combination thereof.

4. The process of claim 1, wherein the supporting layer has a thickness of 1 mm or less.

5. The process of claim 1, further comprising:

introducing a plurality of pores into the supporting layer.

6. The process of claim 5, wherein the supporting layer comprises a plurality of polymer filaments formed on the two-dimensional material by a wet electrospinning process or a dry electrospinning process, the plurality of pores in the supporting layer being introduced as the supporting layer is deposited.

7. The process of claim 5, wherein the supporting layer comprises a polymer film coated on the two-dimensional material, the polymer film further comprising a sacrificial material that is degraded, removed or dissolved after depositing the supporting layer to introduce the plurality of pores in the supporting layer.

8. The process of claim 5, wherein the supporting layer has a porosity gradient throughout its thickness.

9. The process of claim 5, wherein the supporting layer comprises a ceramic material deposited by atomic layer deposition.

10. The process of claim 5, further comprising:

perforating the two-dimensional material to introduce a plurality of pores therein, the plurality of pores in the two-dimensional material being at least 10-fold smaller than the plurality of pores in the supporting layer.

11. The process of claim 10, wherein the two-dimensional material is perforated before depositing the supporting layer thereon.

12. The process of claim 10, wherein the two-dimensional material is perforated after releasing the two-dimensional material from the growth substrate.

13. The process of claim 10, further comprising:

transferring the two-dimensional material and the supporting layer to a secondary substrate.

14. The process of claim 1, further comprising:

perforating the two-dimensional material to introduce a plurality of pores therein.

15. A process comprising:

providing a graphene or graphene-based film adhered to a growth substrate, the growth substrate comprising a metal;

perforating the graphene or graphene-based film to introduce a plurality of pores therein;

depositing a supporting layer on the graphene or graphene-based film while the graphene or graphene-based film is adhered to the growth substrate, the supporting layer also comprising a plurality of pores; and

releasing the graphene or graphene-based film from the growth substrate, the graphene or graphene-based film remaining in contact with the supporting layer following release of the film from the growth substrate.

16. The process of claim 15, wherein releasing the graphene or graphene-based film from the growth substrate comprises etching the growth substrate.

17. The process of claim 16, wherein etching the growth substrate comprises at least partially dissolving the metal with an etch solution.

18. The process of claim 15, wherein the graphene or graphene-based film is perforated before depositing the supporting layer thereon.

19. The process of claim 15, wherein the graphene or graphene-based film is perforated after releasing the graphene or graphene-based film from the growth substrate.

20. The process of claim 15, wherein the plurality of pores in the graphene or graphene-based film are at least 10-fold smaller than the plurality of pores in the supporting layer.

21. The process of claim 15, wherein the supporting layer has a thickness of 1 mm or less.

22. The process of claim 15, further comprising:

transferring the graphene or graphene-based film and the supporting layer to a secondary substrate.

23. The process of claim 22, wherein the secondary substrate contains a plurality of pores.

24. The process of claim 22, wherein the graphene or graphene-based film is sandwiched between the secondary substrate and the supporting layer.

25. The process of claim 15, wherein the supporting layer comprises a porous or permeable polymer or a porous or permeable ceramic material.

26. A filtration membrane comprising a perforated graphene or graphene-based material and a supporting layer, the filtration membrane being prepared by the process of claim 15.