Process for synthesizing reduced graphene oxide on a substrate from seedlac

Patent metadata

Field	Value
Publication number	US-9617159-B2
Application number	US-201414767959-A
Country	US
Kind code	B2
Filing date	May 8, 2014
Priority date	Sep 17, 2013
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

The present invention relates to synthesizing reduced graphene oxide on the surface of a metal sheet and glass. The invention particularly relates to a process for coating a substrate with reduced graphene oxide using seedlac as a carbon source. As per the process of the current invention, a solution of seedlac is prepared in an alcohol and the substrate is dipped in to the solution for one or more time. The substrate is then dried in air for 1-10 minutes and thereafter, heated to a temperature range of 400 to 1200° C. under controlled atmosphere of Ar/N 2 /Ar—H 2 /N 2 —H 2 at a different flow rate ranging from 100 to 500 seem for a period of 10 to 120 minutes.

First claim

We claim:

1. A process for synthesizing reduced graphene oxide from seedlac on a substrate, the process comprising:
preparing a seedlac solution in a C2-C4 alcohol;
dipping the substrate into the seedlac solution one or more times; and
heating the substrate in the temperature range of 400° C. to 1200° C. under a controlled atmosphere of Ar, N 2 , Ar—H 2 , and/or N 2 —H 2 at the flow rate of 100 to 500 sccm for a period of 10 to 120 minutes.

2. The process as claimed in claim 1 , wherein the substrate is a metallic sheet.

3. The process as claimed in claim 2 , wherein the metallic sheet is made of a material selected from the group consisting of steel, copper, zinc, nickel, aluminium and the alloys thereof.

4. The process as claimed in claim 1 , wherein the substrate is a glass sheet.

5. The process as claimed in claim 1 , wherein the C2-C4 alcohol is selected from the group consisting of ethanol, isopropanol and a mixture thereof.

6. The process as claimed in claim 1 , wherein the substrate is an oxidized steel surface.

7. The process as claimed in claim 1 further comprising a step of drying the substrate after each dipping into the seedlac solution by keeping the substrate in an air atmosphere for a period of 1 to 10 minutes.

8. The process as claimed in claim 1 , wherein the seedlac solution is prepared by heating seedlac in the C2-C4 alcohol at a temperature ranging between 60° C. to 90° C. for a period of 10 to 60 minutes.

9. The process as claimed in claim 1 further comprising the step of adding nickel chloride to the seedlac solution in the C2-C4 alcohol.

10. The process as claimed in claim 1 , wherein the concentration of seedlac is in the range of 10-100 gram/liter of the C2-C4 alcohol.

11. The process as claimed in claim 1 , wherein the substrate is heated using an electro-heating furnace.

12. A process for coating a substrate with reduced graphene oxide, the process comprising:
preparing a seedlac solution in a C2-C4 alcohol;
dipping the substrate in to the seedlac solution one or more times; and heating the substrate in the temperature range of 400° C. to 1200° C. under controlled atmosphere of Ar, N 2 , Ar—H 2 , and/or N 2 —H 2 at a flow rate of 100 to 500 sccm for a period of 10 to 120 minutes; wherein a coating thickness of the reduced graphene oxide is in the range of 2-100 nm.

13. The process as claimed in claim 12 , wherein the substrate is a metallic sheet.

14. The process as claimed in claim 13 , wherein the metallic sheet is made of a material selected from the group consisting of steel, copper, zinc, nickel, aluminium and the alloys thereof.

15. The process as claimed in claim 12 , wherein the substrate is a glass sheet.

16. The process as claimed in claim 12 , wherein the C2-C4 alcohol is selected from the group consisting of ethanol, isopropanol and a mixture thereof.

17. The process as claimed in claim 12 , wherein the substrate is an oxidized steel surface.

18. The process as claimed in claim 12 further comprising a step of drying the substrate after each dipping into the seedlac solution by keeping the substrate in an air atmosphere for a period of 1 to 10 minutes.

19. The process as claimed in claim 12 further comprising the step of adding nickel chloride to the seedlac solution in the C2-C4 alcohol.

20. The process as claimed in claim 12 , wherein the seedlac solution is prepared by heating seedlac in C2-C4 alcohol at a temperature ranging between 60° C. to 90° C. for a period of 10 to 60 minutes.

21. The process as claimed in claim 12 , wherein the substrate is heated using an electro-heating furnace.

22. The process as claimed in claim 12 , wherein the concentration of seedlac is in the range of 10-100 gram/liter of C2-C4 alcohol.

Assignees

• Tata Steel Ltd
• Council Scient Ind Res

Inventors

• Shyam Kumar Choudhary
• Manish Kumar Bhadu
• Tapan Kumar Rout
• Sumitesh Das
• Ranjan Kumar Sahu
• Yashabanta Narayan Singhbabu
• Ashit Kumar Pramanick
• Vikas Chandra Srivastava

Classifications

• C09D193/00 Primary

  Coating compositions based on natural resins; Coating compositions based on derivatives thereof (based on polysaccharides C09D101/00 - C09D105/00; based on natural rubber C09D107/00; polishing compositions C09G) · CPC title

• B05D7/14

  to metal, e.g. car bodies (involving a chemical reaction between the metal and the coating C23) · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• B05D7/542

  the two layers being cured or baked together · CPC title

• B05D3/0466 Primary

  the gas being a non-reacting gas (B05D3/0406 takes precedence) · CPC title