We claim:
1. A preparing method of a reduced graphene oxide film, comprising:
coating a graphene oxide-dispersed solution on a substrate to form a graphene oxide thin film; and
reducing the graphene oxide thin film using a chemical reduction method and a pressure-assisted thermal reduction method to form a reduced graphene oxide film,
wherein the pressure-assisted thermal reduction method includes adding heat and pressure to an upper side and a lower side of the substrate on which the graphene oxide thin film is formed.
2. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the substrate includes a flexible plastic substrate.
3. The preparing method of a reduced graphene oxide film of claim 2 ,
wherein the plastic substrate includes a member selected from the group consisting of polyethersulfone, polyimide, polycarbonate, polyehtylene naphthalate, and polyethylene terephthalate.
4. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the substrate is modified by an oxygen plasma treatment or a nitrogen plasma treatment.
5. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the graphene oxide-dispersed solution is prepared by dispersing oxidized graphite in water.
6. The preparing method of a reduced graphene oxide film of claim 5 ,
wherein the graphene oxide-dispersed solution further includes an alcohol of 100 volume % or less with respect to a volume of the water.
7. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the chemical reduction method uses a reducing agent selected from the group consisting of hydrazine, sodium borohydride, and sulfuric acid.
8. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the chemical reduction method is performed at a temperature in a range of from about 70° C. to about 200° C.
9. The preparing method of a reduced graphene oxide film of claim l,
wherein the pressure is about 2,000 kgf/cm 2 or less.
10. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the heat is added at a temperature in a range of from about 70° C. to about 200° C.
11. The preparing method of a reduced graphene oxide film of claim 1 ,
wherein the reduction by adding the heat and the pressure includes using hot-press or hot-plate.