Method of forming graphene/metal-oxide hybrid reinforced composites and product thereof

1. A process for forming a graphene/metal-oxide hybrid reinforced composite, comprising:

freeze drying a slurry comprising graphene oxide and flakes to form a flake-graphene oxide foam;

compressing the flake-graphene oxide foam to form a flake-graphene oxide dense foam;

annealing the flake-graphene oxide dense foam to form a flake-graphene dense foam;

sintering the flake-graphene dense foam to form a bulk graphene/metal-oxide hybrid reinforced composite; and

cold rolling the bulk graphene/metal-oxide hybrid reinforced composite to form the graphene/metal-oxide hybrid reinforced composite.

2. The process for forming a graphene/metal-oxide hybrid reinforced composite according to claim 1 , wherein the flakes are metal flakes.

3. The process for forming a graphene/metal-oxide hybrid reinforced composite according to claim 1 , wherein the flakes are coated with a layer of polymer.

4. The process for forming a graphene/metal-oxide hybrid reinforced composite according to claim 1 , wherein the slurry comprising graphene oxide and flakes is formed by a method comprising:

forming a suspension comprising graphene oxide; and

mixing the suspension comprising graphene oxide with flakes.

5. A process for forming a graphene/metal-oxide hybrid reinforced composite, comprising:

freeze drying a slurry comprising graphene oxide and flakes to form a flake-graphene oxide foam, wherein the flakes are ceramic flakes.

6. A graphene/metal-oxide hybrid reinforced composite, comprising

a) graphene;

b) metal; and

c) metal oxide particles;

wherein the graphene is present in an amount of 0.1 to 5 percent by weight based on total weight of the composite.

7. The graphene/metal-oxide hybrid reinforced composite according to claim 6 , wherein the metal oxide particles are metal oxide nanoparticles.

8. The graphene/metal-oxide hybrid reinforced composite according to claim 6 , wherein the metal is arranged in parallel lamellar structure to form metal layers.

9. The graphene/metal-oxide hybrid reinforced composite according to claim 8 , wherein the graphene and the metal oxide nanoparticles are present between the metal layers.

10. The graphene/metal-oxide hybrid reinforced composite according to claim 8 , wherein the metal oxide nanoparticles are present at the interfaces between the metal layers and the graphene.

11. The graphene/metal-oxide hybrid reinforced composite according to claim 8 , wherein the composite comprises a band comprising the metal oxide nanoparticles at the interfaces between the metal layers and the graphene.

12. The graphene/metal-oxide hybrid reinforced composite according to claim 11 , wherein the composite comprises a sandwiched structure comprising the graphene/the band comprising the metal oxide nanoparticles/the metal in this order.

13. The graphene/metal-oxide hybrid reinforced composite according to claim 7 , wherein the metal oxide nanoparticles are nanoparticles of oxide of the metal in b).

14. The graphene/metal-oxide hybrid reinforced composite according to claim 6 , wherein the metal is selected from the group consisting of Al, Mg, Ti, Cu, Zn, Ni, Fe, Co and combination thereof.

15. The graphene/metal-oxide hybrid reinforced composite according to claim 6 , wherein the metal is aluminum.

16. The graphene/metal-oxide hybrid reinforced composite according to claim 7 , wherein the metal oxide nanoparticles have a rod morphology.

17. The graphene/metal-oxide hybrid reinforced composite according to claim 6 , wherein the graphene/metal-oxide hybrid reinforced composite has a mechanical strength of 240 to 1550 MPa and a toughness of 4500 to 12000 KJ/m 3 .

18. A graphene/metal-oxide hybrid reinforced composite, comprising:

a) graphene;

b) metal; and

c) metal oxide particles;

wherein the metal oxide particles are metal oxide nanoparticles, and

wherein the metal oxide nanoparticles are Al 2 O 3 nanoparticles.