2-dimensional carbon material
2-dimensional carbon thin films are described, as well as their processes of preparation, and their specific uses. The 2-dimensional carbon thin films are fabricated by preparing an organic polymeric thin film precursor, which is then subjected to a carbonisation process to remove at least some of the non-carbon atoms. Using the disclosed process, 2-dimensional carbon thin films having improved dimensional characteristics can be reliably prepared, which presents clear advantages in applications which have until now been restricted to the use of 2-dimensional carbon thin films having less useful dimensions.
1. A continuous 2-dimensional carbon thin film wherein the thin film has a thickness of less than 20 nm and an area divided by thickness ratio (A/T) of greater than 10 10 nm, and wherein the thin film has an elemental composition of:
85 to 95% carbon, and
2 to 13% oxygen;
or;
88 to 98% carbon,
1 to 6% oxygen, and
0.5 to 6% nitrogen.
2. The continuous 2-dimensional carbon thin film of claim 1 , wherein the thin film has a thickness of less than 10 nm.
3. The continuous 2-dimensional carbon thin film of claim 1 , wherein the thin film has a thickness of less than 6 nm.
4. The continuous 2-dimensional carbon thin film of claim 1 , wherein at least a portion of the thin film has a structure corresponding to graphene, graphene oxide or reduced graphene oxide.
5. The continuous 2-dimensional carbon thin film of claim 1 , wherein the thin film comprises 50-70 atomic % of sp 2 carbon atoms.
6. The continuous 2-dimensional carbon thin film of claim 1 , wherein the thin film has a light transmittance at a wavelength of 550 nm of ≥75% at a film thickness of 2-5 nm.
7. The continuous 2-dimensional carbon thin film of claim 1 , wherein, the continuous 2-dimensional carbon thin film has a sheet resistance of ≤10 kΩ/square.
8. The continuous 2-dimensional carbon thin film of claim 1 , wherein the continuous 2-dimensional carbon thin film has an area greater than 0.001 cm 2 .
9. A process for the preparation of the continuous 2-dimensional carbon thin film of claim 1 , the process comprising the steps of:
a) providing an organic polymeric thin film formed by an interfacial polymerisation process, said organic polymeric thin film having a thickness of less than 100 nm; and
b) subjecting the organic polymeric thin film of step a) to a carbonisation process.
10. The process of claim 9 , wherein in step a), the organic polymeric thin film is formed by interfacial polymerisation on a supporting substrate.
11. The process of claim 9 , wherein prior to step b), the organic polymeric thin film is separated from the supporting substrate by contacting the supported organic polymeric thin film with a solvent in which the supporting substrate is soluble and the organic polymeric thin film is insoluble.
12. The process of claim 9 , wherein in step a), the organic polymeric thin film is prepared by interfacial polymerisation at the interface of two immiscible liquids.
13. The process of claim 9 , wherein prior to step b), the organic polymeric thin film is placed on a carbonisation support, and wherein the carbonisation support is selected from silicon, copper, carbon fiber mat, carbon nanotube mat, alumina, or quartz.
14. The process of claim 9 , wherein step b) comprises heating the organic polymeric thin film of step a) to a temperature greater than 300° C. in the absence of oxygen.
15. The process of claim 9 , wherein step b) comprises heating the organic polymeric thin film of step a) to a temperature greater than 900° C. in the absence of oxygen.
16. The process of claim 9 , wherein step b) comprises heating the organic polymeric thin film of step a) to a temperature greater than 1500° C. in the absence of oxygen.
17. The process of claim 9 , wherein step b) comprises heating the organic polymeric thin film of step a) under vacuum.
18. The process of claim 9 , wherein step b) comprises heating the organic polymeric thin film of step a) in an atmosphere comprising greater than 5 vol % hydrogen.
19. The process of claim 9 , wherein the process further comprises contacting the product of carbonisation step b) with a reducing agent, and wherein the reducing agent is selected from hydrazine, chlorine, fluorine, bromine, iodine, hydrogen chloride, hydrogen bromide or hydrogen iodide.
20. The process of claim 9 , wherein the organic polymeric thin film comprises one or more polymers selected from polyamides, polyurea, polypyrrolidines, polyesters, polyurethanes, polyketones, polysiloxanes, poly(amide imide), poly(ether amide) and poly(urea amide).
21. The process of claim 9 , wherein the organic polymeric thin film is a polyamide.