Patent
US 8,173,095METHOD AND APPARATUS FOR PRODUCING GRAPHITE OXIDE LAYERS ON AN INSULATING SUBSTRATE
Walt A. de Heer
US
Copyright © 2026 Matter42. All rights reserved.
Patent
Atlas literature
Patent
US 8,173,095Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a flowchart showing a method for producing graphite oxide layers. [0016]
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
FIG. 3A-3D are a series of schematic diagrams showing a method of making a structure including graphite oxide. [0019]
FIG. 4 is a cross-sectional schematic diagram showing a structure including graphite oxide. [0020]
FIG. 5 is a micrograph of graphite oxide made according to a method disclosed herein.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1.
The method of Claim 12, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 12, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: a. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; b. maintaining the solution at a temperature that is not greater than 20 ° C; and c. agitating the solution.
The method of Claim 3, wherein the oxidizer comprises potassium permanganate.
The method of Claim 3, further comprising the actions o f: a. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 3 of 9 b. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and c. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction.
The method of Claim 12, wherein the inert environment comprises a nitrogen flow.
The method of Claim 12, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
The method of Claim 8, wherein the first masking material comprises a material selected from a group consisting of hydrogen silsesquioxane and SU-8 photoresist.
10.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 4 of 9 11. The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises applying an energy source to the portion of the functionalized graphitic structure.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure; c. drying the functionalized graphitic structure in an inert environment; d. subjecting a portion of the functionalized graphitic structure to a reducing environment; and e. applying a second masking material that resists the reducing environment to a portion of the functionalized graphitic structure prior to the action of subjecting the portion of the functionalized graphitic structure to the reducing environment.
The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises the action of applying an electron beam to the portion of the functionalized graphitic structure.
14.
15.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 5 of 9 16.
17.
18.
-21.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: i. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; ii. maintaining the solution at a temperature that is not greater than 20 0 C; and iii. agitating the solution.; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure, wherein the exposing the portion of the multi- layered graphene surface to a functionalizing material, comprises the actions o f: Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 6 of 9 i. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; ii. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and iii. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction; and c. drying the functionalized graphitic structure in an inert environment.
The method of Claim 22, further comprising the action of subjecting a portion of the functionalized graphitic structure to a reducing environment.
The method of Claim 22, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 22, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: c. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; d. maintaining the solution at a temperature that is not greater than 20 0 C; and e. agitating the solution.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 7 of 9 26. The method of Claim 22, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
Embodiments described in the patent, grouped by the materials and process steps they use.
9 materials2 process steps
A multi-layered graphene surface on SiC is masked, then placed in a solution of 11.5 mL H₂SO₄ and 250 mg NaNO₃ surrounded by a crushed ice bath. 1.5 g KMnO₄ is slowly added while agitating vigorously, keeping temperature below 20 °C. The solution is removed from ice bath and heated to 35 ± 3 °C with agitation until effervescence diminishes (1–30 min). 23 mL distilled water is stirred in; temperature rises to ~98 °C and is maintained for at least 1 minute (e.g., ~15 min). 70 mL warm distilled water and 2 mL 30% H₂O₂ is added to terminate the reaction. Sample is rinsed in deionized water and dried under nitrogen flow. The unmasked portion is converted to graphene oxide. A second mask may then be applied and the exposed graphene oxide subjected to heat or electron beam radiation (100–1100 °C in vacuum, 1 second to 1 hour) to reduce it back to graphene, lowering interfacial charge density.
Layer stacks claimed or described, ordered top of device to substrate.
patterned functionalized graphitic structure
multilayered graphene ribbon (experimental)
Materials described outside the worked examples.
hydrogen silsesquioxane
SU-8 photoresist
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electronic charge density at SiC/graphene interface | 100000000000–10000000000000 electrons per cm² | multi-layered graphene |
Temperature | 100–1100 °C |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,173,095Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a flowchart showing a method for producing graphite oxide layers. [0016]
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
FIG. 3A-3D are a series of schematic diagrams showing a method of making a structure including graphite oxide. [0019]
FIG. 4 is a cross-sectional schematic diagram showing a structure including graphite oxide. [0020]
FIG. 5 is a micrograph of graphite oxide made according to a method disclosed herein.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1.
The method of Claim 12, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 12, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: a. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; b. maintaining the solution at a temperature that is not greater than 20 ° C; and c. agitating the solution.
The method of Claim 3, wherein the oxidizer comprises potassium permanganate.
The method of Claim 3, further comprising the actions o f: a. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 3 of 9 b. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and c. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction.
The method of Claim 12, wherein the inert environment comprises a nitrogen flow.
The method of Claim 12, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
The method of Claim 8, wherein the first masking material comprises a material selected from a group consisting of hydrogen silsesquioxane and SU-8 photoresist.
10.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 4 of 9 11. The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises applying an energy source to the portion of the functionalized graphitic structure.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure; c. drying the functionalized graphitic structure in an inert environment; d. subjecting a portion of the functionalized graphitic structure to a reducing environment; and e. applying a second masking material that resists the reducing environment to a portion of the functionalized graphitic structure prior to the action of subjecting the portion of the functionalized graphitic structure to the reducing environment.
The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises the action of applying an electron beam to the portion of the functionalized graphitic structure.
14.
15.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 5 of 9 16.
17.
18.
-21.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: i. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; ii. maintaining the solution at a temperature that is not greater than 20 0 C; and iii. agitating the solution.; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure, wherein the exposing the portion of the multi- layered graphene surface to a functionalizing material, comprises the actions o f: Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 6 of 9 i. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; ii. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and iii. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction; and c. drying the functionalized graphitic structure in an inert environment.
The method of Claim 22, further comprising the action of subjecting a portion of the functionalized graphitic structure to a reducing environment.
The method of Claim 22, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 22, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: c. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; d. maintaining the solution at a temperature that is not greater than 20 0 C; and e. agitating the solution.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 7 of 9 26. The method of Claim 22, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
Embodiments described in the patent, grouped by the materials and process steps they use.
9 materials2 process steps
A multi-layered graphene surface on SiC is masked, then placed in a solution of 11.5 mL H₂SO₄ and 250 mg NaNO₃ surrounded by a crushed ice bath. 1.5 g KMnO₄ is slowly added while agitating vigorously, keeping temperature below 20 °C. The solution is removed from ice bath and heated to 35 ± 3 °C with agitation until effervescence diminishes (1–30 min). 23 mL distilled water is stirred in; temperature rises to ~98 °C and is maintained for at least 1 minute (e.g., ~15 min). 70 mL warm distilled water and 2 mL 30% H₂O₂ is added to terminate the reaction. Sample is rinsed in deionized water and dried under nitrogen flow. The unmasked portion is converted to graphene oxide. A second mask may then be applied and the exposed graphene oxide subjected to heat or electron beam radiation (100–1100 °C in vacuum, 1 second to 1 hour) to reduce it back to graphene, lowering interfacial charge density.
Layer stacks claimed or described, ordered top of device to substrate.
patterned functionalized graphitic structure
multilayered graphene ribbon (experimental)
Materials described outside the worked examples.
hydrogen silsesquioxane
SU-8 photoresist
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electronic charge density at SiC/graphene interface | 100000000000–10000000000000 electrons per cm² | multi-layered graphene |
Temperature | 100–1100 °C |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,173,095Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a flowchart showing a method for producing graphite oxide layers. [0016]
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
FIG. 3A-3D are a series of schematic diagrams showing a method of making a structure including graphite oxide. [0019]
FIG. 4 is a cross-sectional schematic diagram showing a structure including graphite oxide. [0020]
FIG. 5 is a micrograph of graphite oxide made according to a method disclosed herein.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1.
The method of Claim 12, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 12, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: a. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; b. maintaining the solution at a temperature that is not greater than 20 ° C; and c. agitating the solution.
The method of Claim 3, wherein the oxidizer comprises potassium permanganate.
The method of Claim 3, further comprising the actions o f: a. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 3 of 9 b. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and c. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction.
The method of Claim 12, wherein the inert environment comprises a nitrogen flow.
The method of Claim 12, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
The method of Claim 8, wherein the first masking material comprises a material selected from a group consisting of hydrogen silsesquioxane and SU-8 photoresist.
10.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 4 of 9 11. The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises applying an energy source to the portion of the functionalized graphitic structure.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure; c. drying the functionalized graphitic structure in an inert environment; d. subjecting a portion of the functionalized graphitic structure to a reducing environment; and e. applying a second masking material that resists the reducing environment to a portion of the functionalized graphitic structure prior to the action of subjecting the portion of the functionalized graphitic structure to the reducing environment.
The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises the action of applying an electron beam to the portion of the functionalized graphitic structure.
14.
15.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 5 of 9 16.
17.
18.
-21.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: i. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; ii. maintaining the solution at a temperature that is not greater than 20 0 C; and iii. agitating the solution.; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure, wherein the exposing the portion of the multi- layered graphene surface to a functionalizing material, comprises the actions o f: Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 6 of 9 i. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; ii. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and iii. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction; and c. drying the functionalized graphitic structure in an inert environment.
The method of Claim 22, further comprising the action of subjecting a portion of the functionalized graphitic structure to a reducing environment.
The method of Claim 22, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 22, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: c. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; d. maintaining the solution at a temperature that is not greater than 20 0 C; and e. agitating the solution.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 7 of 9 26. The method of Claim 22, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
Embodiments described in the patent, grouped by the materials and process steps they use.
9 materials2 process steps
A multi-layered graphene surface on SiC is masked, then placed in a solution of 11.5 mL H₂SO₄ and 250 mg NaNO₃ surrounded by a crushed ice bath. 1.5 g KMnO₄ is slowly added while agitating vigorously, keeping temperature below 20 °C. The solution is removed from ice bath and heated to 35 ± 3 °C with agitation until effervescence diminishes (1–30 min). 23 mL distilled water is stirred in; temperature rises to ~98 °C and is maintained for at least 1 minute (e.g., ~15 min). 70 mL warm distilled water and 2 mL 30% H₂O₂ is added to terminate the reaction. Sample is rinsed in deionized water and dried under nitrogen flow. The unmasked portion is converted to graphene oxide. A second mask may then be applied and the exposed graphene oxide subjected to heat or electron beam radiation (100–1100 °C in vacuum, 1 second to 1 hour) to reduce it back to graphene, lowering interfacial charge density.
Layer stacks claimed or described, ordered top of device to substrate.
patterned functionalized graphitic structure
multilayered graphene ribbon (experimental)
Materials described outside the worked examples.
hydrogen silsesquioxane
SU-8 photoresist
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electronic charge density at SiC/graphene interface | 100000000000–10000000000000 electrons per cm² | multi-layered graphene |
Temperature | 100–1100 °C |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,173,095Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a flowchart showing a method for producing graphite oxide layers. [0016]
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
FIG. 3A-3D are a series of schematic diagrams showing a method of making a structure including graphite oxide. [0019]
FIG. 4 is a cross-sectional schematic diagram showing a structure including graphite oxide. [0020]
FIG. 5 is a micrograph of graphite oxide made according to a method disclosed herein.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1.
The method of Claim 12, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 12, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: a. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; b. maintaining the solution at a temperature that is not greater than 20 ° C; and c. agitating the solution.
The method of Claim 3, wherein the oxidizer comprises potassium permanganate.
The method of Claim 3, further comprising the actions o f: a. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 3 of 9 b. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and c. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction.
The method of Claim 12, wherein the inert environment comprises a nitrogen flow.
The method of Claim 12, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
The method of Claim 8, wherein the first masking material comprises a material selected from a group consisting of hydrogen silsesquioxane and SU-8 photoresist.
10.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 4 of 9 11. The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises applying an energy source to the portion of the functionalized graphitic structure.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure; c. drying the functionalized graphitic structure in an inert environment; d. subjecting a portion of the functionalized graphitic structure to a reducing environment; and e. applying a second masking material that resists the reducing environment to a portion of the functionalized graphitic structure prior to the action of subjecting the portion of the functionalized graphitic structure to the reducing environment.
The method of Claim 12, wherein the action of subjecting a portion of the functionalized graphitic structure to a reducing environment comprises the action of applying an electron beam to the portion of the functionalized graphitic structure.
14.
15.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 5 of 9 16.
17.
18.
-21.
A method of making a functionalized graphitic structure, comprising the actions of: a. exposing a portion of a multi-layered graphene surface extending from a silicon carbide substrate to an acidic environment so as to separate graphene layers in a portion of the multi-layered graphene surface, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: i. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; ii. maintaining the solution at a temperature that is not greater than 20 0 C; and iii. agitating the solution.; b. exposing the portion of the multi-layered graphene surface to a functionalizing material that binds to carbon atoms in the graphene sheets so that the functionalizing material remains between the graphene sheets, thereby generating a functionalized graphitic structure, wherein the exposing the portion of the multi- layered graphene surface to a functionalizing material, comprises the actions o f: Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 6 of 9 i. heating the solution to a temperature that is greater than 32 ° C and agitating the solution until visually perceived effervescence of the solution diminishes; ii. adding water to the solution and allowing the solution to increase in temperature until the temperature of the solution is at least 95 ° C and maintaining the solution at a temperature of at least 95 ° C for at least one minute; and iii. adding a solution of water and hydrogen peroxide to the solution, thereby terminating the reaction; and c. drying the functionalized graphitic structure in an inert environment.
The method of Claim 22, further comprising the action of subjecting a portion of the functionalized graphitic structure to a reducing environment.
The method of Claim 22, wherein the action of exposing a portion of the graphitic surface to an acidic environment comprises the actions of: a. submerging the portion of the graphitic surface into a solution of sulfuric acid and sodium nitrate; and b. maintaining the solution at a temperature that is not greater than 20 °C.
The method of Claim 22, wherein the action of exposing the portion of the graphitic surface to a functionalizing material comprises the actions of: c. submerging the portion of the graphitic surface into a solution that includes an oxidizing agent; d. maintaining the solution at a temperature that is not greater than 20 0 C; and e. agitating the solution.
Application No. 12/241,555 Amendment dated 01/19/2012 Reply to Office Action dated 10/19/2011 Page 7 of 9 26. The method of Claim 22, further comprising the action of applying a first masking material to a portion of the multi-layered graphene surface prior to exposing the portion of the multi-layered graphene surface to an acidic environment, the mask material configured to inhibit contact between the portion of the multi-layered graphene surface and the acidic environment, thereby generating a patterned functionalized graphitic structure.
Embodiments described in the patent, grouped by the materials and process steps they use.
9 materials2 process steps
A multi-layered graphene surface on SiC is masked, then placed in a solution of 11.5 mL H₂SO₄ and 250 mg NaNO₃ surrounded by a crushed ice bath. 1.5 g KMnO₄ is slowly added while agitating vigorously, keeping temperature below 20 °C. The solution is removed from ice bath and heated to 35 ± 3 °C with agitation until effervescence diminishes (1–30 min). 23 mL distilled water is stirred in; temperature rises to ~98 °C and is maintained for at least 1 minute (e.g., ~15 min). 70 mL warm distilled water and 2 mL 30% H₂O₂ is added to terminate the reaction. Sample is rinsed in deionized water and dried under nitrogen flow. The unmasked portion is converted to graphene oxide. A second mask may then be applied and the exposed graphene oxide subjected to heat or electron beam radiation (100–1100 °C in vacuum, 1 second to 1 hour) to reduce it back to graphene, lowering interfacial charge density.
Layer stacks claimed or described, ordered top of device to substrate.
patterned functionalized graphitic structure
multilayered graphene ribbon (experimental)
Materials described outside the worked examples.
hydrogen silsesquioxane
SU-8 photoresist
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 2B is a graph showing a current-voltage characteristic of a functionalized graphitic structure made according to a second embodiment. [0018]
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electronic charge density at SiC/graphene interface | 100000000000–10000000000000 electrons per cm² | multi-layered graphene |
Temperature | 100–1100 °C |
Related documents with shared materials, methods, properties, or citations.
| — |
Duration | 1–72000 s | — |
Duration | 1–30 minutes | — |
Temperature | ≤ 20 °C | — |
— | ≥ 1 eV | — |
Temperature | ≥ 20 °C | — |
Temperature | ≥ 32 °C | — |
Temperature | ≥ 95 °C | — |
| — |
Duration | 1–72000 s | — |
Duration | 1–30 minutes | — |
Temperature | ≤ 20 °C | — |
— | ≥ 1 eV | — |
Temperature | ≥ 20 °C | — |
Temperature | ≥ 32 °C | — |
Temperature | ≥ 95 °C | — |
| — |
Duration | 1–72000 s | — |
Duration | 1–30 minutes | — |
Temperature | ≤ 20 °C | — |
— | ≥ 1 eV | — |
Temperature | ≥ 20 °C | — |
Temperature | ≥ 32 °C | — |
Temperature | ≥ 95 °C | — |
| — |
Duration | 1–72000 s | — |
Duration | 1–30 minutes | — |
Temperature | ≤ 20 °C | — |
— | ≥ 1 eV | — |
Temperature | ≥ 20 °C | — |
Temperature | ≥ 32 °C | — |
Temperature | ≥ 95 °C | — |