METAL NANOPARTICLE-GRAPHENE COMPOSITES AND METHODS FOR THEIR PREPARATION AND USE | Matter42 Literature
Patent
Atlas literature
Patent
US 10,003,084
METAL NANOPARTICLE-GRAPHENE COMPOSITES AND METHODS FOR THEIR PREPARATION AND USE
Ramaprabhu Sundara
US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
6 independent · 18 dependent
1
Independenthydrogen-exfoliated graphene sheetgraphite oxideH₂liquid medium
A method to form a metal nanoparticle-graphene composite, the method comprising: mixing a metal precursor with graphite oxide in [[the]]presence of a liquid medium to form a metal precursor-graphite oxide mixture; exfoliating the graphite oxide of the metal precursor-graphite oxide mixture with hydrogen to chemically modify the graphite oxide to form a hydrogen-exfoliated graphene sheet; and while exfoliating the graphite oxide, simultaneously reducing the metal precursor in the metal precursor-graphite oxide mixture to adsorb metal nanoparticles on a first major surface of the hydrogen-exfoliated graphene sheet. Currently amended
3
Dependent← claim 1metal nanoparticles
The method of claim 1, wherein the metal nanoparticles comprise platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
4
Dependent← claim 1metal precursor
The method of claim 1, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
5
Dependent← claim 1H₂PtCl6·6H₂O
The method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 O). Original
6
Dependent← claim 1liquid medium (water, acetone, ethanol, toluene, or combinations)
The method of claim 1, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
7
Dependent← claim 1
The method of claim 1, further comprising drying the metal precursor-graphite oxide mixture before exfoliating the graphite oxide of the metal precursor-graphite oxide mixture. Previously presented
The method of claim 1, wherein exfoliating the graphite oxide and reducing the metal precursor comprises: contacting hydrogen gas (H 2) with oxygen-based functional groups of the graphite oxide within a reaction chamber to form the hydrogen-exfoliated graphene sheet; and reducing the metal precursor using a hydrogen gas to attach the metal nanoparticles to the hydrogen-exfoliated graphene sheet. Previously presented
14
Dependent← claim 1H₂PtCl6·6H₂OPt
The i method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0) and the metal nanoparticles comprise platinum nanoparticles. Currently amended
The method of claim 1, wherein a density of graphene in the metal nanoparticle-graphene composite is about 0.5 g/cm 3 to about 0.8 g/cm 3. Currently amended
A mixture comprising: a metal precursor; graphite oxide; hydrogen gas; a liquid medium; a hydrogen-exfoliated graphene sheet; and a plurality of platinum nanoparticles dispersed on a first major surface of the hydrogen- exfoliated graphene sheet. Previously presented
31
Dependent← claim 30metal precursor
The mixture of claim 30, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Previously presented
32
Dependent← claim 30H₂PtCl6·6H₂O
The mixture of claim 30, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0). Previously presented
33
Dependent← claim 30liquid medium (water, acetone, ethanol, toluene, or combinations)
The mixture of claim 30, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
The mixture of claim 30, wherein the hydrogen-exfoliated graphene sheet and the plurality of platinum nanoparticles dispersed on the first major surface of the hydrogen-exfoliated graphene sheet to form an electrocatalyst, an average size of the platinum nanoparticles of the platinum nanoparticles is about 3 nanometers to about 5 nanometers, and a current density of the electrocatalyst is at least about 1239 mA cm 2. Previously presented
36
Dependent← claim 30Pt
The mixture of claim 30, wherein an average particle size of the plurality of platinum nanoparticles is about 3.3 nanometers. Previously presented
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
electrocatalyst
Ptactive catalyst
hydrogen-exfoliated graphene sheetsupport
Materials
Materials described outside the worked examples.
hydrogen-exfoliated graphene sheet
Support/Substrate For Metal Nanoparticles; Composite Component
graphite oxide
Precursor To Hydrogen-Exfoliated Graphene
Process steps
Additional fabrication and treatment steps described in the patent.
1
Hydrogen Exfoliation And Reduction
Step 1
Temperature
200, 600°C
Ambient
H2
Process details
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
average platinum nanoparticle size (claimed range)
3–5 nm
Pt
average platinum nanoparticle size (specific value)
—
Why these are connected
Related documents with shared materials, methods, properties, or citations.
METAL NANOPARTICLE-GRAPHENE COMPOSITES AND METHODS FOR THEIR PREPARATION AND USE
Ramaprabhu Sundara
US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
6 independent · 18 dependent
1
Independenthydrogen-exfoliated graphene sheetgraphite oxideH₂liquid medium
A method to form a metal nanoparticle-graphene composite, the method comprising: mixing a metal precursor with graphite oxide in [[the]]presence of a liquid medium to form a metal precursor-graphite oxide mixture; exfoliating the graphite oxide of the metal precursor-graphite oxide mixture with hydrogen to chemically modify the graphite oxide to form a hydrogen-exfoliated graphene sheet; and while exfoliating the graphite oxide, simultaneously reducing the metal precursor in the metal precursor-graphite oxide mixture to adsorb metal nanoparticles on a first major surface of the hydrogen-exfoliated graphene sheet. Currently amended
3
Dependent← claim 1metal nanoparticles
The method of claim 1, wherein the metal nanoparticles comprise platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
4
Dependent← claim 1metal precursor
The method of claim 1, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
5
Dependent← claim 1H₂PtCl6·6H₂O
The method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 O). Original
6
Dependent← claim 1liquid medium (water, acetone, ethanol, toluene, or combinations)
The method of claim 1, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
7
Dependent← claim 1
The method of claim 1, further comprising drying the metal precursor-graphite oxide mixture before exfoliating the graphite oxide of the metal precursor-graphite oxide mixture. Previously presented
The method of claim 1, wherein exfoliating the graphite oxide and reducing the metal precursor comprises: contacting hydrogen gas (H 2) with oxygen-based functional groups of the graphite oxide within a reaction chamber to form the hydrogen-exfoliated graphene sheet; and reducing the metal precursor using a hydrogen gas to attach the metal nanoparticles to the hydrogen-exfoliated graphene sheet. Previously presented
14
Dependent← claim 1H₂PtCl6·6H₂OPt
The i method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0) and the metal nanoparticles comprise platinum nanoparticles. Currently amended
The method of claim 1, wherein a density of graphene in the metal nanoparticle-graphene composite is about 0.5 g/cm 3 to about 0.8 g/cm 3. Currently amended
A mixture comprising: a metal precursor; graphite oxide; hydrogen gas; a liquid medium; a hydrogen-exfoliated graphene sheet; and a plurality of platinum nanoparticles dispersed on a first major surface of the hydrogen- exfoliated graphene sheet. Previously presented
31
Dependent← claim 30metal precursor
The mixture of claim 30, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Previously presented
32
Dependent← claim 30H₂PtCl6·6H₂O
The mixture of claim 30, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0). Previously presented
33
Dependent← claim 30liquid medium (water, acetone, ethanol, toluene, or combinations)
The mixture of claim 30, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
The mixture of claim 30, wherein the hydrogen-exfoliated graphene sheet and the plurality of platinum nanoparticles dispersed on the first major surface of the hydrogen-exfoliated graphene sheet to form an electrocatalyst, an average size of the platinum nanoparticles of the platinum nanoparticles is about 3 nanometers to about 5 nanometers, and a current density of the electrocatalyst is at least about 1239 mA cm 2. Previously presented
36
Dependent← claim 30Pt
The mixture of claim 30, wherein an average particle size of the plurality of platinum nanoparticles is about 3.3 nanometers. Previously presented
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
electrocatalyst
Ptactive catalyst
hydrogen-exfoliated graphene sheetsupport
Materials
Materials described outside the worked examples.
hydrogen-exfoliated graphene sheet
Support/Substrate For Metal Nanoparticles; Composite Component
graphite oxide
Precursor To Hydrogen-Exfoliated Graphene
Process steps
Additional fabrication and treatment steps described in the patent.
1
Hydrogen Exfoliation And Reduction
Step 1
Temperature
200, 600°C
Ambient
H2
Process details
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
average platinum nanoparticle size (claimed range)
3–5 nm
Pt
average platinum nanoparticle size (specific value)
—
Why these are connected
Related documents with shared materials, methods, properties, or citations.
METAL NANOPARTICLE-GRAPHENE COMPOSITES AND METHODS FOR THEIR PREPARATION AND USE
Ramaprabhu Sundara
US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
6 independent · 18 dependent
1
Independenthydrogen-exfoliated graphene sheetgraphite oxideH₂liquid medium
A method to form a metal nanoparticle-graphene composite, the method comprising: mixing a metal precursor with graphite oxide in [[the]]presence of a liquid medium to form a metal precursor-graphite oxide mixture; exfoliating the graphite oxide of the metal precursor-graphite oxide mixture with hydrogen to chemically modify the graphite oxide to form a hydrogen-exfoliated graphene sheet; and while exfoliating the graphite oxide, simultaneously reducing the metal precursor in the metal precursor-graphite oxide mixture to adsorb metal nanoparticles on a first major surface of the hydrogen-exfoliated graphene sheet. Currently amended
3
Dependent← claim 1metal nanoparticles
The method of claim 1, wherein the metal nanoparticles comprise platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
4
Dependent← claim 1metal precursor
The method of claim 1, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
5
Dependent← claim 1H₂PtCl6·6H₂O
The method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 O). Original
6
Dependent← claim 1liquid medium (water, acetone, ethanol, toluene, or combinations)
The method of claim 1, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
7
Dependent← claim 1
The method of claim 1, further comprising drying the metal precursor-graphite oxide mixture before exfoliating the graphite oxide of the metal precursor-graphite oxide mixture. Previously presented
The method of claim 1, wherein exfoliating the graphite oxide and reducing the metal precursor comprises: contacting hydrogen gas (H 2) with oxygen-based functional groups of the graphite oxide within a reaction chamber to form the hydrogen-exfoliated graphene sheet; and reducing the metal precursor using a hydrogen gas to attach the metal nanoparticles to the hydrogen-exfoliated graphene sheet. Previously presented
14
Dependent← claim 1H₂PtCl6·6H₂OPt
The i method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0) and the metal nanoparticles comprise platinum nanoparticles. Currently amended
The method of claim 1, wherein a density of graphene in the metal nanoparticle-graphene composite is about 0.5 g/cm 3 to about 0.8 g/cm 3. Currently amended
A mixture comprising: a metal precursor; graphite oxide; hydrogen gas; a liquid medium; a hydrogen-exfoliated graphene sheet; and a plurality of platinum nanoparticles dispersed on a first major surface of the hydrogen- exfoliated graphene sheet. Previously presented
31
Dependent← claim 30metal precursor
The mixture of claim 30, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Previously presented
32
Dependent← claim 30H₂PtCl6·6H₂O
The mixture of claim 30, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0). Previously presented
33
Dependent← claim 30liquid medium (water, acetone, ethanol, toluene, or combinations)
The mixture of claim 30, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
The mixture of claim 30, wherein the hydrogen-exfoliated graphene sheet and the plurality of platinum nanoparticles dispersed on the first major surface of the hydrogen-exfoliated graphene sheet to form an electrocatalyst, an average size of the platinum nanoparticles of the platinum nanoparticles is about 3 nanometers to about 5 nanometers, and a current density of the electrocatalyst is at least about 1239 mA cm 2. Previously presented
36
Dependent← claim 30Pt
The mixture of claim 30, wherein an average particle size of the plurality of platinum nanoparticles is about 3.3 nanometers. Previously presented
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
electrocatalyst
Ptactive catalyst
hydrogen-exfoliated graphene sheetsupport
Materials
Materials described outside the worked examples.
hydrogen-exfoliated graphene sheet
Support/Substrate For Metal Nanoparticles; Composite Component
graphite oxide
Precursor To Hydrogen-Exfoliated Graphene
Process steps
Additional fabrication and treatment steps described in the patent.
1
Hydrogen Exfoliation And Reduction
Step 1
Temperature
200, 600°C
Ambient
H2
Process details
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
average platinum nanoparticle size (claimed range)
3–5 nm
Pt
average platinum nanoparticle size (specific value)
—
Why these are connected
Related documents with shared materials, methods, properties, or citations.
METAL NANOPARTICLE-GRAPHENE COMPOSITES AND METHODS FOR THEIR PREPARATION AND USE
Ramaprabhu Sundara
US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
6 independent · 18 dependent
1
Independenthydrogen-exfoliated graphene sheetgraphite oxideH₂liquid medium
A method to form a metal nanoparticle-graphene composite, the method comprising: mixing a metal precursor with graphite oxide in [[the]]presence of a liquid medium to form a metal precursor-graphite oxide mixture; exfoliating the graphite oxide of the metal precursor-graphite oxide mixture with hydrogen to chemically modify the graphite oxide to form a hydrogen-exfoliated graphene sheet; and while exfoliating the graphite oxide, simultaneously reducing the metal precursor in the metal precursor-graphite oxide mixture to adsorb metal nanoparticles on a first major surface of the hydrogen-exfoliated graphene sheet. Currently amended
3
Dependent← claim 1metal nanoparticles
The method of claim 1, wherein the metal nanoparticles comprise platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
4
Dependent← claim 1metal precursor
The method of claim 1, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Original
5
Dependent← claim 1H₂PtCl6·6H₂O
The method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 O). Original
6
Dependent← claim 1liquid medium (water, acetone, ethanol, toluene, or combinations)
The method of claim 1, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
7
Dependent← claim 1
The method of claim 1, further comprising drying the metal precursor-graphite oxide mixture before exfoliating the graphite oxide of the metal precursor-graphite oxide mixture. Previously presented
The method of claim 1, wherein exfoliating the graphite oxide and reducing the metal precursor comprises: contacting hydrogen gas (H 2) with oxygen-based functional groups of the graphite oxide within a reaction chamber to form the hydrogen-exfoliated graphene sheet; and reducing the metal precursor using a hydrogen gas to attach the metal nanoparticles to the hydrogen-exfoliated graphene sheet. Previously presented
14
Dependent← claim 1H₂PtCl6·6H₂OPt
The i method of claim 1, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0) and the metal nanoparticles comprise platinum nanoparticles. Currently amended
The method of claim 1, wherein a density of graphene in the metal nanoparticle-graphene composite is about 0.5 g/cm 3 to about 0.8 g/cm 3. Currently amended
A mixture comprising: a metal precursor; graphite oxide; hydrogen gas; a liquid medium; a hydrogen-exfoliated graphene sheet; and a plurality of platinum nanoparticles dispersed on a first major surface of the hydrogen- exfoliated graphene sheet. Previously presented
31
Dependent← claim 30metal precursor
The mixture of claim 30, wherein the metal precursor comprises platinum (Pt), palladium (Pd), silver (Ag), gold (Au), nickel (Ni), titanium (Ti), tin (Sn), ruthenium (Ru), or combinations thereof. Previously presented
32
Dependent← claim 30H₂PtCl6·6H₂O
The mixture of claim 30, wherein the metal precursor comprises hexachloroplatinic acid (H 2 PtC₁ 6.6H 2 0). Previously presented
33
Dependent← claim 30liquid medium (water, acetone, ethanol, toluene, or combinations)
The mixture of claim 30, wherein the liquid medium is water, acetone, ethanol, toluene, or combinations thereof. Previously presented
The mixture of claim 30, wherein the hydrogen-exfoliated graphene sheet and the plurality of platinum nanoparticles dispersed on the first major surface of the hydrogen-exfoliated graphene sheet to form an electrocatalyst, an average size of the platinum nanoparticles of the platinum nanoparticles is about 3 nanometers to about 5 nanometers, and a current density of the electrocatalyst is at least about 1239 mA cm 2. Previously presented
36
Dependent← claim 30Pt
The mixture of claim 30, wherein an average particle size of the plurality of platinum nanoparticles is about 3.3 nanometers. Previously presented
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
electrocatalyst
Ptactive catalyst
hydrogen-exfoliated graphene sheetsupport
Materials
Materials described outside the worked examples.
hydrogen-exfoliated graphene sheet
Support/Substrate For Metal Nanoparticles; Composite Component
graphite oxide
Precursor To Hydrogen-Exfoliated Graphene
Process steps
Additional fabrication and treatment steps described in the patent.
1
Hydrogen Exfoliation And Reduction
Step 1
Temperature
200, 600°C
Ambient
H2
Process details
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
average platinum nanoparticle size (claimed range)
3–5 nm
Pt
average platinum nanoparticle size (specific value)
—
Why these are connected
Related documents with shared materials, methods, properties, or citations.
Active Nanoparticle Component Of Composite (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
metal precursor
Precursor For Metal Nanoparticles (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
hexachloroplatinic acid
H₂PtCl6·6H₂O
Metal Precursor For Platinum Nanoparticles
liquid medium (water, acetone, ethanol, toluene, or combinations)
Solvent/Dispersion Medium
platinum nanoparticles
Pt
Active Electrocatalyst Nanoparticles Dispersed On Graphene Surface
steps:
Mix metal precursor with graphite oxide in liquid medium, Optionally dry the metal precursor-graphite oxide mixture, Contact hydrogen gas with graphite oxide in reaction chamber to exfoliate and form hydrogen-exfoliated graphene sheet, Simultaneously reduce metal precursor with hydrogen gas to form metal nanoparticles adsorbed on graphene surface
Active Nanoparticle Component Of Composite (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
metal precursor
Precursor For Metal Nanoparticles (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
hexachloroplatinic acid
H₂PtCl6·6H₂O
Metal Precursor For Platinum Nanoparticles
liquid medium (water, acetone, ethanol, toluene, or combinations)
Solvent/Dispersion Medium
platinum nanoparticles
Pt
Active Electrocatalyst Nanoparticles Dispersed On Graphene Surface
steps:
Mix metal precursor with graphite oxide in liquid medium, Optionally dry the metal precursor-graphite oxide mixture, Contact hydrogen gas with graphite oxide in reaction chamber to exfoliate and form hydrogen-exfoliated graphene sheet, Simultaneously reduce metal precursor with hydrogen gas to form metal nanoparticles adsorbed on graphene surface
Active Nanoparticle Component Of Composite (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
metal precursor
Precursor For Metal Nanoparticles (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
hexachloroplatinic acid
H₂PtCl6·6H₂O
Metal Precursor For Platinum Nanoparticles
liquid medium (water, acetone, ethanol, toluene, or combinations)
Solvent/Dispersion Medium
platinum nanoparticles
Pt
Active Electrocatalyst Nanoparticles Dispersed On Graphene Surface
steps:
Mix metal precursor with graphite oxide in liquid medium, Optionally dry the metal precursor-graphite oxide mixture, Contact hydrogen gas with graphite oxide in reaction chamber to exfoliate and form hydrogen-exfoliated graphene sheet, Simultaneously reduce metal precursor with hydrogen gas to form metal nanoparticles adsorbed on graphene surface
Active Nanoparticle Component Of Composite (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
metal precursor
Precursor For Metal Nanoparticles (Pt, Pd, Ag, Au, Ni, Ti, Sn, Ru, Or Combinations)
hexachloroplatinic acid
H₂PtCl6·6H₂O
Metal Precursor For Platinum Nanoparticles
liquid medium (water, acetone, ethanol, toluene, or combinations)
Solvent/Dispersion Medium
platinum nanoparticles
Pt
Active Electrocatalyst Nanoparticles Dispersed On Graphene Surface
steps:
Mix metal precursor with graphite oxide in liquid medium, Optionally dry the metal precursor-graphite oxide mixture, Contact hydrogen gas with graphite oxide in reaction chamber to exfoliate and form hydrogen-exfoliated graphene sheet, Simultaneously reduce metal precursor with hydrogen gas to form metal nanoparticles adsorbed on graphene surface
