Process for producing graphene
A process for producing graphene by providing a plurality of metallic particles as templates for graphene formation and providing a carbon source; reacting the metallic particles and carbon source under conditions suitable for graphene formation; and forming graphene particles on the metallic particles. The graphene particles formed on the metallic particles are of a size and shape substantially corresponding to the size and shape of the metallic particles.
1. A process for producing graphene comprising the steps of:
providing a plurality of metallic particles as templates for graphene formation;
providing a carbon source;
reacting the metallic particles and carbon source under conditions suitable for graphene formation; and
forming graphene particles on the metallic particles,
wherein the graphene particles formed on the metallic particles are of a size and shape substantially corresponding to the size and shape of the metallic particles, and
wherein the metallic particles are dispersed and suspended as spaced-apart solid particles in a wet or dry fluidized support medium so each particle provides a template for graphene production.
2. A process as claimed in claim 1 , wherein the carbon source and metallic particles or precursor thereof are fed into a reactor.
3. A process as claimed in claim 2 , wherein the process is a substantially continuous process.
4. A process as claimed in claim 1 , wherein the metallic particles are fed into the reactor in a dispersion, solvent, vapour, aerosol, or spray.
5. A process as claimed in claim 2 , wherein the graphene particles are removed substantially continuously from the reactor.
6. A process as claimed in claim 1 , wherein the graphene particles are formed by chemical vapour deposition.
7. A process as claimed in claim 1 , wherein the graphene particles are formed in a single layer or multiple layers.
8. A process as claimed in claim 1 , wherein the thickness of graphene formed on the metallic particles is controlled by adjusting flow rate and/or reaction time.
9. A process as claimed in claim 1 , wherein the metallic particles each comprise at least one substantially flat surface on which the graphene particles form.
10. A process as claimed in claim 1 , wherein the metallic particles have an aspect ratio of around 1:10 or lower.
11. A process as claimed in claim 10 , wherein the metallic particles comprise belts having a lateral dimension of about 50 nm by 500 nm and a thickness of about 40-50 nm.
12. A process as claimed in claim 10 , wherein the metallic particles have an aspect ratio of around 1:1.
13. A process as claimed in claim 12 , wherein the metallic particles comprise platelets having a lateral dimension of about 1-2 μm and a thickness of about 40-50 nm.
14. A process as claimed in claim 1 , wherein the metallic particles comprise a transition metal or compound thereof.
15. A process as claimed in claim 14 , wherein the transition metal is selected from the group of nickel, iron, cobalt, copper, platinum, iridium, ruthenium and gold.
16. A process as claimed in claim 15 , wherein the metallic particles comprise cobalt hydroxide.
17. A process as claimed in claim 1 , wherein the support medium comprises magnesium oxide, silicon, aluminium oxide, silicon oxide, aluminosilicates, zeolites, MCM-41 or MC-8.
18. A process as claimed in claim 1 , wherein the metallic particles are present in the support medium at about 1-10 wt %.
19. A process as claimed in claim 1 , wherein the graphene is removed from the support medium and/or metallic particles by a single dissolution step.
20. A process as claimed in claim 1 , further comprising the step of connecting the graphene particles to form a film.