Patent
US 8,696,938Supercritical Fluid Process for Producing Nano Graphene Platelets
Aruna Zhamu
US
Copyright © 2026 Matter42. All rights reserved.
Patent
Atlas literature
Patent
US 8,696,938Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
FIG. 3 (A) A graphite fiber sample after first cycle of supercritical fluid intercalation and 25 exfoliation (original graphite fibers of substantially spherical …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A process for producing a nano graphene platelet (NGP) material, said process comprising: (i) subjecting a graphitic material to a supercritical fluid at a first temperature and a first pressure for a first period of time in a pressure vessel, wherein said supercritical fluid contains no coating agent solubilized therein and no intercalating agent or oxidizing agent is used in the process, and said graphitic material comprises no previously intercalated graphite and said graphitic material is selected from the group consisting of natural graphite, artificial graphite, graphite oxide, graphite fluoride, graphite fiber, carbon fiber, carbon nano-fiber, carbon nano-tube, soft carbon, hard carbon, and combinations thereof; and then (ii) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting exfoliation of said graphitic material to obtain said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid comprises a fluid selected from carbon dioxide, water, water oxidation, hydrogen peroxide (H₂ O 2), methane, ethane, ethylene, ozone, sulfonic group (SO 3), or a combination thereof.
The process as set forth in claim 1 further comprising a procedure of repeating step (i) and step (ii) that includes (a) subjecting said NGP material to a supercritical fluid at a second temperature and a second pressure for a second period of time in a pressure vessel and then (b) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting further exfoliation of said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid contains a surfactant or dispersing agent dissolved therein.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises mixing said nano graphene material with a thermosetting resin.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises a procedure of repeating step (i) and step (ii) and a procedure of mixing said graphene material with a resin.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 nm, exhibits an electrical conductivity of at least 100 S/cm.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 num, exhibits an electrical conductivity of at least 1,000 S/cm.
The process as set forth in claim 1 wherein said nano graphene material has a specific surface area of approximately from 300 m2/g to 2,600
The process as set forth in claim 1 wherein said single-layer graphene.
The process as set forth in claim 1, further nano graphene material in said pressure vessel.
The process as set forth in claim 1, wherein chemical group.
The process as set forth in claim 1, wherein chemical group and a surfactant. m2/g. nano graphene platelet material comprises comprising imparting a chemical group to said said supercritical fluid comprises a reactive said supercritical fluid comprises a reactive
3.
9.
10.
Materials described outside the worked examples.
nano graphene platelet (NGP)
natural graphite
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 100 S/cm | — | nano graphene platelet (NGP) |
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 1000 S/cm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,696,938Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
FIG. 3 (A) A graphite fiber sample after first cycle of supercritical fluid intercalation and 25 exfoliation (original graphite fibers of substantially spherical …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A process for producing a nano graphene platelet (NGP) material, said process comprising: (i) subjecting a graphitic material to a supercritical fluid at a first temperature and a first pressure for a first period of time in a pressure vessel, wherein said supercritical fluid contains no coating agent solubilized therein and no intercalating agent or oxidizing agent is used in the process, and said graphitic material comprises no previously intercalated graphite and said graphitic material is selected from the group consisting of natural graphite, artificial graphite, graphite oxide, graphite fluoride, graphite fiber, carbon fiber, carbon nano-fiber, carbon nano-tube, soft carbon, hard carbon, and combinations thereof; and then (ii) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting exfoliation of said graphitic material to obtain said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid comprises a fluid selected from carbon dioxide, water, water oxidation, hydrogen peroxide (H₂ O 2), methane, ethane, ethylene, ozone, sulfonic group (SO 3), or a combination thereof.
The process as set forth in claim 1 further comprising a procedure of repeating step (i) and step (ii) that includes (a) subjecting said NGP material to a supercritical fluid at a second temperature and a second pressure for a second period of time in a pressure vessel and then (b) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting further exfoliation of said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid contains a surfactant or dispersing agent dissolved therein.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises mixing said nano graphene material with a thermosetting resin.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises a procedure of repeating step (i) and step (ii) and a procedure of mixing said graphene material with a resin.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 nm, exhibits an electrical conductivity of at least 100 S/cm.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 num, exhibits an electrical conductivity of at least 1,000 S/cm.
The process as set forth in claim 1 wherein said nano graphene material has a specific surface area of approximately from 300 m2/g to 2,600
The process as set forth in claim 1 wherein said single-layer graphene.
The process as set forth in claim 1, further nano graphene material in said pressure vessel.
The process as set forth in claim 1, wherein chemical group.
The process as set forth in claim 1, wherein chemical group and a surfactant. m2/g. nano graphene platelet material comprises comprising imparting a chemical group to said said supercritical fluid comprises a reactive said supercritical fluid comprises a reactive
3.
9.
10.
Materials described outside the worked examples.
nano graphene platelet (NGP)
natural graphite
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 100 S/cm | — | nano graphene platelet (NGP) |
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 1000 S/cm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,696,938Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
FIG. 3 (A) A graphite fiber sample after first cycle of supercritical fluid intercalation and 25 exfoliation (original graphite fibers of substantially spherical …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A process for producing a nano graphene platelet (NGP) material, said process comprising: (i) subjecting a graphitic material to a supercritical fluid at a first temperature and a first pressure for a first period of time in a pressure vessel, wherein said supercritical fluid contains no coating agent solubilized therein and no intercalating agent or oxidizing agent is used in the process, and said graphitic material comprises no previously intercalated graphite and said graphitic material is selected from the group consisting of natural graphite, artificial graphite, graphite oxide, graphite fluoride, graphite fiber, carbon fiber, carbon nano-fiber, carbon nano-tube, soft carbon, hard carbon, and combinations thereof; and then (ii) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting exfoliation of said graphitic material to obtain said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid comprises a fluid selected from carbon dioxide, water, water oxidation, hydrogen peroxide (H₂ O 2), methane, ethane, ethylene, ozone, sulfonic group (SO 3), or a combination thereof.
The process as set forth in claim 1 further comprising a procedure of repeating step (i) and step (ii) that includes (a) subjecting said NGP material to a supercritical fluid at a second temperature and a second pressure for a second period of time in a pressure vessel and then (b) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting further exfoliation of said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid contains a surfactant or dispersing agent dissolved therein.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises mixing said nano graphene material with a thermosetting resin.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises a procedure of repeating step (i) and step (ii) and a procedure of mixing said graphene material with a resin.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 nm, exhibits an electrical conductivity of at least 100 S/cm.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 num, exhibits an electrical conductivity of at least 1,000 S/cm.
The process as set forth in claim 1 wherein said nano graphene material has a specific surface area of approximately from 300 m2/g to 2,600
The process as set forth in claim 1 wherein said single-layer graphene.
The process as set forth in claim 1, further nano graphene material in said pressure vessel.
The process as set forth in claim 1, wherein chemical group.
The process as set forth in claim 1, wherein chemical group and a surfactant. m2/g. nano graphene platelet material comprises comprising imparting a chemical group to said said supercritical fluid comprises a reactive said supercritical fluid comprises a reactive
3.
9.
10.
Materials described outside the worked examples.
nano graphene platelet (NGP)
natural graphite
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 100 S/cm | — | nano graphene platelet (NGP) |
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 1000 S/cm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,696,938Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
FIG. 3 (A) A graphite fiber sample after first cycle of supercritical fluid intercalation and 25 exfoliation (original graphite fibers of substantially spherical …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A process for producing a nano graphene platelet (NGP) material, said process comprising: (i) subjecting a graphitic material to a supercritical fluid at a first temperature and a first pressure for a first period of time in a pressure vessel, wherein said supercritical fluid contains no coating agent solubilized therein and no intercalating agent or oxidizing agent is used in the process, and said graphitic material comprises no previously intercalated graphite and said graphitic material is selected from the group consisting of natural graphite, artificial graphite, graphite oxide, graphite fluoride, graphite fiber, carbon fiber, carbon nano-fiber, carbon nano-tube, soft carbon, hard carbon, and combinations thereof; and then (ii) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting exfoliation of said graphitic material to obtain said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid comprises a fluid selected from carbon dioxide, water, water oxidation, hydrogen peroxide (H₂ O 2), methane, ethane, ethylene, ozone, sulfonic group (SO 3), or a combination thereof.
The process as set forth in claim 1 further comprising a procedure of repeating step (i) and step (ii) that includes (a) subjecting said NGP material to a supercritical fluid at a second temperature and a second pressure for a second period of time in a pressure vessel and then (b) rapidly depressurizing said fluid at a fluid release rate sufficient for effecting further exfoliation of said NGP material.
The process as set forth in claim 1 wherein said supercritical fluid contains a surfactant or dispersing agent dissolved therein.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises mixing said nano graphene material with a thermosetting resin.
The process as set forth in claim 1 wherein said supercritical fluid contains a curing agent dissolved therein and the process further comprises a procedure of repeating step (i) and step (ii) and a procedure of mixing said graphene material with a resin.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 nm, exhibits an electrical conductivity of at least 100 S/cm.
The process as set forth in claim 1 wherein said nano graphene platelet material, when formed into a thin film with a thickness no greater than 100 num, exhibits an electrical conductivity of at least 1,000 S/cm.
The process as set forth in claim 1 wherein said nano graphene material has a specific surface area of approximately from 300 m2/g to 2,600
The process as set forth in claim 1 wherein said single-layer graphene.
The process as set forth in claim 1, further nano graphene material in said pressure vessel.
The process as set forth in claim 1, wherein chemical group.
The process as set forth in claim 1, wherein chemical group and a surfactant. m2/g. nano graphene platelet material comprises comprising imparting a chemical group to said said supercritical fluid comprises a reactive said supercritical fluid comprises a reactive
3.
9.
10.
Materials described outside the worked examples.
nano graphene platelet (NGP)
natural graphite
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 The thickness of NGPs prepared with or without a surfactant dissolved in a supercritical fluid. The pressure vessel containing NGPs, after the first …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 100 S/cm | — | nano graphene platelet (NGP) |
electrical conductivity of NGP thin film (thickness <= 100 nm), claimed minimum 1000 S/cm |
Related documents with shared materials, methods, properties, or citations.
artificial graphite
graphite oxide
graphite fluoride
graphite fiber
carbon fiber
carbon nano-fiber
carbon nano-tube
soft carbon
hard carbon
carbon dioxide
CO₂
water
H₂O
hydrogen peroxide
H₂O₂
methane
CH₄
ethane
C₂H₆
ethylene
C₂H₄
ozone
O₃
sulfonic group
SO₃
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
nano graphene platelet (NGP) |
specific surface area of NGP material, claimed range 300 to 2600 m2/g | — | nano graphene platelet (NGP) |
Duration | 5–30 seconds | — |
Pressure | 7.4–69 MPa | — |
Duration | 600–86400 s | — |
Pressure | 1070–10000 psi | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Pressure | ≥ 7.4 MPa | — |
Pressure | ≥ 22.1 MPa | — |
Thickness | ≥ 1 nm | — |
Thickness | 0.34–0.4 nm | — |
Thickness | ≤ 2 nm | — |
Duration | ≤ 15 seconds | — |
artificial graphite
graphite oxide
graphite fluoride
graphite fiber
carbon fiber
carbon nano-fiber
carbon nano-tube
soft carbon
hard carbon
carbon dioxide
CO₂
water
H₂O
hydrogen peroxide
H₂O₂
methane
CH₄
ethane
C₂H₆
ethylene
C₂H₄
ozone
O₃
sulfonic group
SO₃
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
nano graphene platelet (NGP) |
specific surface area of NGP material, claimed range 300 to 2600 m2/g | — | nano graphene platelet (NGP) |
Duration | 5–30 seconds | — |
Pressure | 7.4–69 MPa | — |
Duration | 600–86400 s | — |
Pressure | 1070–10000 psi | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Pressure | ≥ 7.4 MPa | — |
Pressure | ≥ 22.1 MPa | — |
Thickness | ≥ 1 nm | — |
Thickness | 0.34–0.4 nm | — |
Thickness | ≤ 2 nm | — |
Duration | ≤ 15 seconds | — |
artificial graphite
graphite oxide
graphite fluoride
graphite fiber
carbon fiber
carbon nano-fiber
carbon nano-tube
soft carbon
hard carbon
carbon dioxide
CO₂
water
H₂O
hydrogen peroxide
H₂O₂
methane
CH₄
ethane
C₂H₆
ethylene
C₂H₄
ozone
O₃
sulfonic group
SO₃
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
nano graphene platelet (NGP) |
specific surface area of NGP material, claimed range 300 to 2600 m2/g | — | nano graphene platelet (NGP) |
Duration | 5–30 seconds | — |
Pressure | 7.4–69 MPa | — |
Duration | 600–86400 s | — |
Pressure | 1070–10000 psi | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Pressure | ≥ 7.4 MPa | — |
Pressure | ≥ 22.1 MPa | — |
Thickness | ≥ 1 nm | — |
Thickness | 0.34–0.4 nm | — |
Thickness | ≤ 2 nm | — |
Duration | ≤ 15 seconds | — |
artificial graphite
graphite oxide
graphite fluoride
graphite fiber
carbon fiber
carbon nano-fiber
carbon nano-tube
soft carbon
hard carbon
carbon dioxide
CO₂
water
H₂O
hydrogen peroxide
H₂O₂
methane
CH₄
ethane
C₂H₆
ethylene
C₂H₄
ozone
O₃
sulfonic group
SO₃
FIG. 2 (A) An MCMB sample after the first cycle of supercritical fluid intercalation and. exfoliation; and (B) A TEM image of the resulting NGPs after a repeated …
nano graphene platelet (NGP) |
specific surface area of NGP material, claimed range 300 to 2600 m2/g | — | nano graphene platelet (NGP) |
Duration | 5–30 seconds | — |
Pressure | 7.4–69 MPa | — |
Duration | 600–86400 s | — |
Pressure | 1070–10000 psi | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Pressure | ≥ 7.4 MPa | — |
Pressure | ≥ 22.1 MPa | — |
Thickness | ≥ 1 nm | — |
Thickness | 0.34–0.4 nm | — |
Thickness | ≤ 2 nm | — |
Duration | ≤ 15 seconds | — |