Graphene synthesis

1. A method of preparing a deposited graphene in the form of a continuous film comprising the steps of:

sealing a metal substrate and a carbon source in an ambient environment at ambient temperature to create a sealed ambient environment comprising a sealed ambient atmosphere;

heating the sealed ambient environment to a temperature which produces carbon vapour from the carbon source such that the carbon vapour comes into contact with a surface of the metal substrate;

maintaining the temperature for a time sufficient to form a graphene lattice and then cooling the metal substrate at a controlled rate to form a deposited graphene continuous film on the surface of the metal substrate that contacts the carbon vapour; and

wherein the carbon source is a liquid or solid biomass, is derived from a biomass, or is a purified biomass;

wherein the entire carbon source is not in contact with the metal substrate;

wherein the method is free from the use of compressed or feedstock gases;

wherein the sealed ambient atmosphere consists of air at atmospheric pressure or a vacuum;

wherein the temperature which produces the carbon vapour from the carbon source is in the range of 650° C. to 900° C.; and

wherein cooling the metal substrate at a controlled rate controls thickness of the deposited graphene continuous film.

2. The method according to claim 1 wherein the metal substrate is a transition metal substrate.

3. The method according to claim 1 wherein the metal substrate is nickel or copper.

4. The method according to claim 3 wherein the metal substrate is nickel and the sealed ambient atmosphere is air at atmospheric pressure.

5. The method according to claim 3 wherein the metal substrate is polycrystalline nickel.

6. The method according to claim 3 wherein the metal substrate is copper and the sealed ambient atmosphere is vacuum.

7. The method according to claim 1 wherein the carbon source is a liquid.

8. The method according to claim 1 wherein the carbon source is soybean oil.

9. The method according to claim 1 wherein a ratio of carbon source to surface area of the metal substrate is 0.01-0.03 mL/cm 2 .

10. The method according to claim 1 wherein the metal substrate and carbon source are both located in one heating zone.

11. The method according to claim 10 wherein the temperature sufficient to form a graphene lattice is maintained at 800° C.

12. The method according to claim 10 wherein the temperature sufficient to form a graphene lattice is maintained at 900° C.

13. The method according to claim 1 wherein the sealed ambient environment is contained in an inert container.

14. The method according to claim 1 wherein the sealed ambient environment is a quartz, glass or other dielectric heat resistant container.

15. The method according to claim 14 wherein the deposited graphene is in the form of a single layer.

16. The method according to claim 14 wherein the deposited graphene is in the form of 1-19 layers.

17. The method according to claim 1 , wherein the temperature sufficient to form the graphene lattice is maintained for 3-15 minutes.

18. The method according to claim 1 wherein the deposited graphene is in the form of 20-40 layers.

19. The method according to claim 1 wherein the deposited graphene is in the form of >40 layers.

20. The method according to claim 1 wherein the substrate is cooled at a controlled rate to segregate the graphene lattice from the metal substrate.

21. The method according to claim 1 wherein the substrate is cooled to ambient temperature at a rate of 10-100° C./minute.

22. The method according to claim 1 further comprising the step of decoupling graphene from the substrate.