Patent
US 8,226,801Mass Production of Pristine Nano Graphene Materials
Aruna Zhamu
US
Copyright © 2026 Matter42. All rights reserved.
Patent
Atlas literature
Patent
US 8,226,801Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 Conventional, most commonly used chemical processes for producing oxidized NGPs or GO platelets.
FIG. 2 A surfactant-assisted direct ultrasonication method disclosed earlier by the instant 5 applicants.
FIG. 3 (A) Schematic of graphite crystallites in a graphitic material; each crystallite is a stack of graphene planes bonded together along the …
FIG. 4 Graphene plane contact angle values of various liquids plotted as a function of liquid l0 surface tension.
FIG. 5 Graphene edge surface contact angle values of various liquids plotted as a function of liquid surface tension.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
FIG. 7 A perceived view of how low surface tension solvent-assisted direct ultrasonication works to produce ultra-thin graphene sheets.
FIG. 8 The graphene surface contact angle data for those liquids considered "good solvents" for solvating or dissolving graphene molecules according to the …
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a liquid medium containing therein no surfactant to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a surface tension that enables wetting of said liquid on a graphene plane exhibiting a contact angle less than 90 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient energy or intensity level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 1 wherein said contact angle is less than 75 degrees.
The method of claim 1 wherein said contact angle is less than 60 degrees.
The method of claim 1 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 1 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 1 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 1 mg/mL.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 10 mg/mL.
The method of claim 1 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 1 wherein said ultrasonication step is conducted at a temperature lower than 100 *C.
The method of claim 1 wherein said energy level is greater than 150 watts.
The method of claim 1 wherein said energy level is greater than 250 watts.
The method of claim 1 wherein said pristine graphitic material comprises a material selected from the group consisting of natural graphite, synthetic graphite, highly oriented pyrolytic graphite, meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof.
The method of claim 1 wherein said liquid medium further contains a monomer or a polymer dissolved or dispersed therein to form a nanocomposite precursor suspension.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a power level greater than 150 watts for a sufficient length of time to produce said nano graphene platelets.
The method of claim 19 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 19 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 19 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 19 wherein said liquid medium has a surface tension value 4 lower than 30 mN/m.
A method of producing nano graphene platelets, said method comprising: a) providing a graphitic material selected from the group consisting of meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof; wherein said graphitic material comprises at least a graphite crystallite having at least a graphene plane and an edge surface and wherein said graphitic material has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient power level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 24 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 24 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 24 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 24 wherein said liquid medium has a surface tension value lower than mN/m.
Materials described outside the worked examples.
pristine graphitic material
nano graphene platelets
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
Thickness | 10–80 nm | — |
Thickness | ≤ 0.2 mm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,226,801Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 Conventional, most commonly used chemical processes for producing oxidized NGPs or GO platelets.
FIG. 2 A surfactant-assisted direct ultrasonication method disclosed earlier by the instant 5 applicants.
FIG. 3 (A) Schematic of graphite crystallites in a graphitic material; each crystallite is a stack of graphene planes bonded together along the …
FIG. 4 Graphene plane contact angle values of various liquids plotted as a function of liquid l0 surface tension.
FIG. 5 Graphene edge surface contact angle values of various liquids plotted as a function of liquid surface tension.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
FIG. 7 A perceived view of how low surface tension solvent-assisted direct ultrasonication works to produce ultra-thin graphene sheets.
FIG. 8 The graphene surface contact angle data for those liquids considered "good solvents" for solvating or dissolving graphene molecules according to the …
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a liquid medium containing therein no surfactant to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a surface tension that enables wetting of said liquid on a graphene plane exhibiting a contact angle less than 90 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient energy or intensity level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 1 wherein said contact angle is less than 75 degrees.
The method of claim 1 wherein said contact angle is less than 60 degrees.
The method of claim 1 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 1 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 1 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 1 mg/mL.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 10 mg/mL.
The method of claim 1 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 1 wherein said ultrasonication step is conducted at a temperature lower than 100 *C.
The method of claim 1 wherein said energy level is greater than 150 watts.
The method of claim 1 wherein said energy level is greater than 250 watts.
The method of claim 1 wherein said pristine graphitic material comprises a material selected from the group consisting of natural graphite, synthetic graphite, highly oriented pyrolytic graphite, meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof.
The method of claim 1 wherein said liquid medium further contains a monomer or a polymer dissolved or dispersed therein to form a nanocomposite precursor suspension.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a power level greater than 150 watts for a sufficient length of time to produce said nano graphene platelets.
The method of claim 19 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 19 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 19 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 19 wherein said liquid medium has a surface tension value 4 lower than 30 mN/m.
A method of producing nano graphene platelets, said method comprising: a) providing a graphitic material selected from the group consisting of meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof; wherein said graphitic material comprises at least a graphite crystallite having at least a graphene plane and an edge surface and wherein said graphitic material has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient power level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 24 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 24 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 24 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 24 wherein said liquid medium has a surface tension value lower than mN/m.
Materials described outside the worked examples.
pristine graphitic material
nano graphene platelets
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
Thickness | 10–80 nm | — |
Thickness | ≤ 0.2 mm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,226,801Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 Conventional, most commonly used chemical processes for producing oxidized NGPs or GO platelets.
FIG. 2 A surfactant-assisted direct ultrasonication method disclosed earlier by the instant 5 applicants.
FIG. 3 (A) Schematic of graphite crystallites in a graphitic material; each crystallite is a stack of graphene planes bonded together along the …
FIG. 4 Graphene plane contact angle values of various liquids plotted as a function of liquid l0 surface tension.
FIG. 5 Graphene edge surface contact angle values of various liquids plotted as a function of liquid surface tension.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
FIG. 7 A perceived view of how low surface tension solvent-assisted direct ultrasonication works to produce ultra-thin graphene sheets.
FIG. 8 The graphene surface contact angle data for those liquids considered "good solvents" for solvating or dissolving graphene molecules according to the …
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a liquid medium containing therein no surfactant to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a surface tension that enables wetting of said liquid on a graphene plane exhibiting a contact angle less than 90 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient energy or intensity level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 1 wherein said contact angle is less than 75 degrees.
The method of claim 1 wherein said contact angle is less than 60 degrees.
The method of claim 1 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 1 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 1 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 1 mg/mL.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 10 mg/mL.
The method of claim 1 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 1 wherein said ultrasonication step is conducted at a temperature lower than 100 *C.
The method of claim 1 wherein said energy level is greater than 150 watts.
The method of claim 1 wherein said energy level is greater than 250 watts.
The method of claim 1 wherein said pristine graphitic material comprises a material selected from the group consisting of natural graphite, synthetic graphite, highly oriented pyrolytic graphite, meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof.
The method of claim 1 wherein said liquid medium further contains a monomer or a polymer dissolved or dispersed therein to form a nanocomposite precursor suspension.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a power level greater than 150 watts for a sufficient length of time to produce said nano graphene platelets.
The method of claim 19 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 19 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 19 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 19 wherein said liquid medium has a surface tension value 4 lower than 30 mN/m.
A method of producing nano graphene platelets, said method comprising: a) providing a graphitic material selected from the group consisting of meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof; wherein said graphitic material comprises at least a graphite crystallite having at least a graphene plane and an edge surface and wherein said graphitic material has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient power level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 24 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 24 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 24 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 24 wherein said liquid medium has a surface tension value lower than mN/m.
Materials described outside the worked examples.
pristine graphitic material
nano graphene platelets
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
Thickness | 10–80 nm | — |
Thickness | ≤ 0.2 mm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,226,801Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 Conventional, most commonly used chemical processes for producing oxidized NGPs or GO platelets.
FIG. 2 A surfactant-assisted direct ultrasonication method disclosed earlier by the instant 5 applicants.
FIG. 3 (A) Schematic of graphite crystallites in a graphitic material; each crystallite is a stack of graphene planes bonded together along the …
FIG. 4 Graphene plane contact angle values of various liquids plotted as a function of liquid l0 surface tension.
FIG. 5 Graphene edge surface contact angle values of various liquids plotted as a function of liquid surface tension.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
FIG. 7 A perceived view of how low surface tension solvent-assisted direct ultrasonication works to produce ultra-thin graphene sheets.
FIG. 8 The graphene surface contact angle data for those liquids considered "good solvents" for solvating or dissolving graphene molecules according to the …
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a liquid medium containing therein no surfactant to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a surface tension that enables wetting of said liquid on a graphene plane exhibiting a contact angle less than 90 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient energy or intensity level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 1 wherein said contact angle is less than 75 degrees.
The method of claim 1 wherein said contact angle is less than 60 degrees.
The method of claim 1 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 1 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 1 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said liquid medium has a surface tension value lower than mN/m.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 1 mg/mL.
The method of claim 1 wherein said suspension has a graphitic material concentration greater than 10 mg/mL.
The method of claim 1 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 1 wherein said ultrasonication step is conducted at a temperature lower than 100 *C.
The method of claim 1 wherein said energy level is greater than 150 watts.
The method of claim 1 wherein said energy level is greater than 250 watts.
The method of claim 1 wherein said pristine graphitic material comprises a material selected from the group consisting of natural graphite, synthetic graphite, highly oriented pyrolytic graphite, meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof.
The method of claim 1 wherein said liquid medium further contains a monomer or a polymer dissolved or dispersed therein to form a nanocomposite precursor suspension.
A method of producing pristine nano graphene platelets, said method comprising: a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface, wherein said pristine graphitic material is defined as a graphitic material that has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said pristine graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said multiple particles in said liquid have a concentration greater than 0.1 mg/mL and said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a power level greater than 150 watts for a sufficient length of time to produce said nano graphene platelets.
The method of claim 19 wherein at least 99% of the pristine graphitic material is converted into nano graphene platelets.
The method of claim 19 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 19 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 19 wherein said liquid medium has a surface tension value 4 lower than 30 mN/m.
A method of producing nano graphene platelets, said method comprising: a) providing a graphitic material selected from the group consisting of meso-carbon micro-bead, carbon or graphite fiber, carbon or graphitic nano-fiber, partially graphitized pitch, soft carbon, hard carbon, pyrolitic coke, and combinations thereof; wherein said graphitic material comprises at least a graphite crystallite having at least a graphene plane and an edge surface and wherein said graphitic material has never been subjected to intercalation, chemical oxidation, fluorination, solvating or dissolving by a solvent; b) dispersing multiple particles of said graphitic material in a surfactant-free liquid medium to produce a suspension, wherein said liquid medium is characterized by having a graphene plane contact angle less than 75 degrees; and c) exposing said suspension to direct ultrasonication at a sufficient power level for a sufficient length of time to produce said nano graphene platelets.
The method of claim 24 wherein said contact angle is less than 45 degrees or said nano graphene platelets have an average thickness less than 20 nm.
The method of claim 24 wherein said contact angle is less than 30 degrees or said nano graphene platelets have an average thickness less than 10 nm.
The method of claim 24 wherein said nano graphene platelets have an average thickness less than 1 nm.
The method of claim 24 wherein said liquid medium has a surface tension value lower than mN/m.
Materials described outside the worked examples.
pristine graphitic material
nano graphene platelets
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 6 Average thickness of NGPs obtained by direct ultrasonication in various liquids, platted as a function of graphene plane contact angle values. 15
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
Thickness | 10–80 nm | — |
Thickness | ≤ 0.2 mm |
Related documents with shared materials, methods, properties, or citations.
natural graphite
graphite oxide/graphene oxide (GO)
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
| — |
Thickness | ≤ 0.01 mm | — |
Thickness | ≤ 20 nm | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Thickness | ≥ 1 nm | — |
Thickness | ≤ 2 nm | — |
natural graphite
graphite oxide/graphene oxide (GO)
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
| — |
Thickness | ≤ 0.01 mm | — |
Thickness | ≤ 20 nm | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Thickness | ≥ 1 nm | — |
Thickness | ≤ 2 nm | — |
natural graphite
graphite oxide/graphene oxide (GO)
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
| — |
Thickness | ≤ 0.01 mm | — |
Thickness | ≤ 20 nm | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Thickness | ≥ 1 nm | — |
Thickness | ≤ 2 nm | — |
natural graphite
graphite oxide/graphene oxide (GO)
FIG. 9 The electrical conductivity data of three series of NGP-epoxy composites, one featuring pristine graphene as a reinforcement, the second chemically …
FIG.10 Transmission electron micrograph of select NGP.
| — |
Thickness | ≤ 0.01 mm | — |
Thickness | ≤ 20 nm | — |
Thickness | ≤ 10 nm | — |
Thickness | ≤ 1 nm | — |
Thickness | ≥ 1 nm | — |
Thickness | ≤ 2 nm | — |