Graphene oxide and reduced graphene oxide GO, rGO
Carbon sheet with variable epoxy, hydroxyl, carbonyl and carboxyl groups · Two-dimensional sheet
Graphene oxide (GO) is a graphene sheet carrying oxygen groups (epoxy, hydroxyl, carbonyl and carboxyl), made by oxidising graphite.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Stiffness
6 to 42 GPa
Electrical conduction
0.0486 S/m
Heat conduction
< 10 W/(m·K)
Water permeation
10 Å
Recipe, share of the weight
- C not statedCarbon
- O not statedOxygen
- H not statedHydrogen
Best for
Water-permeable membranes, polymer composites and films where an insulating or water-dispersible carbon sheet is wanted
Weakest at
Electrical and thermal performance: GO is an insulator, and reduced GO depends on the reduction route, so no single value describes it
Risk at a glance
- People Low. Handle as a precaution
- If it fails Moderate. Oxygen groups decompose on heating
- Corrosion Moderate. Oxygen groups break down at high temperature
Quick facts: GO, rGO
| Property | Value | Basis |
|---|---|---|
| Tensile strength | 76 to 293 MPa | 2 sourced values across conditions |
| Young's modulus | 6 to 250 GPa | 4 sourced values across conditions |
| Thermal conductivity | 10 W/(m·K) | 1 sourced value |
What is the thermal conductivity of Graphene oxide and reduced graphene oxide (GO, rGO)?
Graphene oxide and reduced graphene oxide (GO, rGO) has a thermal conductivity of 10 W/(m·K). The source and test conditions are listed in the properties table on this page.
What is the tensile strength of Graphene oxide and reduced graphene oxide (GO, rGO)?
Graphene oxide and reduced graphene oxide (GO, rGO) has a tensile strength of 76 to 293 MPa. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the Young's modulus of Graphene oxide and reduced graphene oxide (GO, rGO)?
Graphene oxide and reduced graphene oxide (GO, rGO) has a Young's modulus of 6 to 250 GPa. The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is Graphene oxide and reduced graphene oxide (GO, rGO) used for?
Uses recorded in the sources include GO and polyvinyl alcohol composite (laboratory); Reduced GO films as transparent conductors and in field-effect transistors (research); GO and rGO films as low-conductivity thermal layers (research).
Why it exists
Graphene oxide is graphene carrying oxygen groups. The groups make the sheet an electrical insulator and cut its heat conduction, but they also let it disperse in water and bind to other materials. Reduction removes some of the groups and raises conductivity. The useful numbers depend on the oxidation level, the form (paper, film or monolayer) and humidity, so most values here are ranges.
Where it's used
Polymer composites
A review table lists GO modified with polyvinyl alcohol at a Young's modulus of 8 GPa, against 5 GPa for the unmodified GO in the same row. The tensile strength in that row is 125 MPa against 25 MPa.
Membranes
In a laboratory test, GO membranes stopped helium while letting water through at least 10^10 times faster than helium. This is a research result and not a space system.
Films and devices
The review lists transparent and flexible conductors and field-effect transistors as device applications of GO and reduced GO. These are research demonstrations.
Recipe
Carbon sheet with variable epoxy, hydroxyl, carbonyl and carboxyl groups; no fixed formula
Graphene oxide is made by oxidising graphite, usually with the Hummers method (sulfuric acid and potassium permanganate), and then exfoliating the oxidised graphite in water. The sheet keeps a carbon lattice with epoxy bridges, hydroxyl groups on its faces, and carbonyl and carboxyl groups at its edges. Reduced graphene oxide has lost some of those groups, for example by thermal exfoliation at a suggested minimum of 550 C or by chemical reduction with hydrazine.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Carbon C | not stated | Forms the sheet. Oxidised areas hold carbon bonded to oxygen, which breaks the flat sp2 lattice locally. |
| Oxygen O | not stated | Sits in epoxy bridges, hydroxyl, carbonyl and carboxyl groups. Its amount sets the C/O ratio and how far the conductivity is suppressed. |
| Hydrogen H | not stated | Sits on hydroxyl and carboxyl groups. Hydrogen species in as-made GO are thought to make the film metastable, according to the review. |
Weight shares are as printed in the sources.
What it can do
Stiffness
6 to 42 GPa
measured
Bulk GO paper is cited at 6 to 42 GPa in Young's modulus. A GO monolayer is quoted at 250 GPa, with a printed spread of 150 GPa. Measured values depend on oxidation, water content and test method.
Electrical conduction
0.0486 S/m
measured
GO is an insulator, cited as low as 0.0486 S/m. Reduction raises the value: 0.052 S/m for a reduced monolayer, 55.32 S/m for a Shewanella-reduced rGO, and 216.56 S/m for a hydrazine-reduced rGO used as the comparison.
Heat conduction
< 10 W/(m·K)
measured
GO and rGO papers and films are cited below 10 W/(m·K). Simulations at an O:C ratio of 0.1 give 35, 85 and 29 W/(m·K) for epoxy, hydroxyl and ether groups, which are not measurements.
Water permeation
10 Å
measured
GO membranes let water through much faster than helium. Annealing at 300 C in hydrogen and argon shrinks the interlayer distance from about 10 Å to about 4 Å and makes the membrane about 100 times less permeable to water.
How it compares
Graphene oxide and reduced graphene oxide are not graphene. Graphene is quoted in the review at 1 TPa in stiffness and with far higher thermal conduction at room temperature, both for ideal sheets. GO has oxygen on those sheets, so its electrical conductivity drops to 0.0486 S/m as the lowest value cited, and its films conduct heat below 10 W/(m·K). Reduction recovers some conductivity, to between 0.052 and 216.56 S/m across the cited cases, depending on the reductant. The comparison is with graphene's ideal values, not with a commercial graphene product.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | GO, rGO | Graphene |
|---|---|---|
| Thermal behavior and safety | ||
| Thermal conductivity, GO and rGO papers or thin films (upper bound) | < 10 W/(m·K)7 | 2000 to 5000 W/mK |
| Thermal conductivity, epoxy-functionalised GO (simulation) | 35 W/(m·K)8 | 2000 to 5000 W/mK |
| Thermal conductivity, hydroxyl-functionalised GO (simulation) | 85 W/(m·K)9 | 2000 to 5000 W/mK |
| Thermal conductivity, ether-functionalised GO (simulation) | 29 W/(m·K)10 | 2000 to 5000 W/mK |
| Temperature above which GO oxygen groups decomposeStatement in the review | > 1000 K13 | no data |
| Physical and electrical | ||
| Electrical conductivity, GO (lowest value cited)Value quoted in an open-access 2026 review | 0.0486 S/m | no data |
| Electrical conductivity, rGO monolayer after chemical reduction | 0.052 S/m6 | no data |
| Electrical conductivity, rGO reduced by ShewanellaValue quoted in an open-access 2026 review | 55.32 S/m | no data |
| Electrical conductivity, rGO reduced by hydrazine (comparison case)Value quoted in an open-access 2026 review | 216.6 S/m | no data |
| Other measurements | ||
| Young's modulus, bulk GO paper | 6 to 42 GPa1 | no data |
| Tensile strength, bulk GO paper (the review calls it intrinsic strength) | 76 to 293 MPa2 | no data |
| Young's modulus, GO monolayer (review value) | 250 GPa3 | no data |
| Intrinsic strength, GO monolayer (review value) | 30 to 50 GPa4 | 130 GPa |
| Young's modulus, GO modified with polyvinyl alcoholValue printed in Table 1 of the review | 8 GPa | no data |
| Tensile strength, GO modified with polyvinyl alcoholValue printed in Table 1 of the review | 125 MPa | no data |
| Out-of-plane Young's modulus, conventional GO at 25 percent relative humidity | 35 GPa5 | no data |
| Interlayer distance of a GO membraneX-ray analysis, as stated in the paper | 10 Å11 | no data |
| Interlayer distance of GO after annealing at 300 C in hydrogen and argonX-ray analysis, as stated in the paper | 4 Å12 | no data |
| C/O ratio of rGO reduced with hydrazine | 9.82 -14 | no data |
Why choose it, and why not
Good for
- Water-permeable membranes and laminates at laboratory stage, where a gas-tight but water-passing layer is the goal.
- Polymer composites: the review's polyvinyl alcohol example raises Young's modulus from 5 GPa to 8 GPa.
- Low-conductivity films where heat must not spread, such as thermoelectric research.
Watch out for
- Pure GO is electrically insulating. Reduction changes conductivity by orders of magnitude, and the result depends on the reductant.
- Stiffness and strength values span wide ranges. The monolayer value of 250 GPa carries a printed spread of 150 GPa.
- Humidity changes the out-of-plane stiffness and the layer spacing, so properties drift with moisture.
- Above about 1000 K the oxygen groups decompose, which changes the material.
GO suits laboratory work on water-permeable membranes and polymer composites. For electrical and thermal use, the reduction route and the form decide the result. No space or flight data were found.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Young's modulus, bulk GO paper | Range quoted in an open-access review, which cites ref 13 of that review | basis GO paper (stacked sheets); range printed in the review for different oxidation degrees and thicknessestest not stated in the review | — |
| 2 | Tensile strength, bulk GO paper (the review calls it intrinsic strength) | Range quoted in the review, in the same paragraph as the modulus | basis GO paper (stacked sheets); range printed in the review | — |
| 3 | Young's modulus, GO monolayer (review value) | Value quoted in the review, citing ref 11 of that review | basis GO monolayer; printed as 250 ± 150 GPatest not stated in the review | The printed spread is ± 150 GPa, so this single value is a wide estimate, not a measured range. |
| 4 | Intrinsic strength, GO monolayer (review value) | Range quoted in the review, citing ref 11 of that review | basis GO monolayer; range printed in the review, paired with the monolayer modulus above | Snake-case name, not in the property canon; see gaps. |
| 5 | Out-of-plane Young's modulus, conventional GO at 25 percent relative humidity | Experimental value quoted in the review and matched by DFT with intercalated water | basis conventional porous GO at relative humidity 25 percent, out-of-plane direction | Printed as 35 ± 10 GPa at ambient humidity. The modulus changes with humidity, so it is not a fixed value. |
| 6 | Electrical conductivity, rGO monolayer after chemical reduction | Value quoted in the review, citing Gomez-Navarro et al. (ref 189 of the review) | basis chemically reduced rGO monolayer on a silicon substrate, room temperature (298 K) | The review says this is still about three orders of magnitude below pristine graphene. |
| 7 | Thermal conductivity, GO and rGO papers or thin films (upper bound) | Statement in the review, citing two experimental papers (refs 316 and 317 of the review) | basis GO or rGO paper or thin film; test temperature not stated in the review | The review attributes the low value to phonon scattering at the junctions between GO nanoplatelets. |
| 8 | Thermal conductivity, epoxy-functionalised GO (simulation) | Non-equilibrium molecular dynamics result quoted in the review; a simulation, not a measurement | basis GO with epoxy groups at O:C ratio 0.1, sample length 300 nm | — |
| 9 | Thermal conductivity, hydroxyl-functionalised GO (simulation) | Non-equilibrium molecular dynamics result quoted in the review; a simulation, not a measurement | basis GO with hydroxyl groups at O:C ratio 0.1, sample length 300 nm | — |
| 10 | Thermal conductivity, ether-functionalised GO (simulation) | Non-equilibrium molecular dynamics result quoted in the review; a simulation, not a measurement | basis GO with ether groups at O:C ratio 0.1, sample length 300 nm | — |
| 11 | Interlayer distance of a GO membrane | — | basis GO membrane as printed (about 10 Å); hydration state not stated | Snake-case name, not in the property canon; see gaps. Printed as approximately 10 Å. |
| 12 | Interlayer distance of GO after annealing at 300 C in hydrogen and argon | — | basis GO annealed at 300 C in a hydrogen and argon atmosphere; printed as about 4 Å for reduced GO | The same annealing made the membranes about 100 times less permeable to water. |
| 13 | Temperature above which GO oxygen groups decompose | — | basis thermodynamic stability limit for the oxygen groups, as stated in the review | Snake-case name, not in the property canon. The review gives a stated limit, not a measured onset. |
| 14 | C/O ratio of rGO reduced with hydrazine | Value printed in the review text on chemical reduction | basis rGO made by hydrazine reduction; ratio as printed | A higher C/O ratio means fewer oxygen groups. The review gives no numeric C/O ratio for untreated GO. |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Water and humidity (hydration and ageing) | not rated | Water content changes GO stiffness and layer spacing1 |
| Water (aqueous dispersion) | not rated | GO disperses in water; rGO tends to restack2 |
| Heat above about 1000 K | moderate | Oxygen groups break down at high temperature3 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Water and humidity (hydration and ageing) | The review says the out-of-plane stiffness of conventional GO depends on intercalated water, peaking near RH 25 percent. It also says ageing of GO gathers oxygen groups into highly oxidised domains, so the material changes over time. No ageing rate, time or temperature was read in a source. | basis qualitative statements in the review; no exposure time or temperature stated |
| 2 | Water (aqueous dispersion) | The review says GO forms stable colloidal dispersions in water because its oxygen groups make it highly reactive and hydrophilic. Reduced GO has a strong tendency to agglomerate and restack in aqueous solution. | basis qualitative statements in the review; dispersion concentration not stated |
| 3 | Heat above about 1000 K | The review says the oxygen-containing groups decompose above about 1000 K, and that thermal exfoliation of graphite oxide needs a suggested minimum of 550 C to give RGO. The groups break down into gases during that step. | basis decomposition of oxygen groups; no heating time or atmosphere stated |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The supplier sheet for a dispersion classifies it as an eye and airway irritant, and no exposure limit is set for graphene oxide.
- Eyes and airways
- A supplier sheet for a 0.5 mg/mL dispersion gives serious eye irritation (H319) and respiratory irritation (H335), with no signal word.
- Dust
- Keep dust out of the air with local exhaust ventilation. HSE says nanomaterials are substances of high concern, and graphite's threshold is not an appropriate limit for graphene.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Oxygen groups decompose on heatingmoderate severity | Heating above about 1000 KThe oxygen groups break down, so the material is no longer GO in its as-made form. A design that relies on the as-made oxygen content will fail. |
| Membrane becomes fragile and much less permeable after annealingmoderate severity | Annealing GO membranes at 300 C in hydrogen and argonThe membranes became fragile and needed care to avoid cracks, and became about 100 times less permeable to water. |
| Stiffness shifts with humiditylow severity | Change in relative humidity or water contentThe out-of-plane modulus of conventional GO depends on water content, with a maximum near RH 25 percent, so a film's stiffness is not fixed. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Sheet size and yield of the product | During thermal exfoliation the epoxy and hydroxyl groups decompose into gases, and a suggested minimum of 550 C is needed for the product to be RGO. |
| Processing of dispersions and films | Reduced GO has a strong tendency to agglomerate and restack in water, so its dispersions can lose their state. |
Handling and storage
- Keep dust-generating work under local exhaust ventilation, and where possible keep the material wet or damp or use slurries.
- Weigh powders over a damp sheet of absorbent material, and wipe spills with a damp sheet rather than dry sweeping.
- Avoid dust formation and provide exhaust ventilation where dust forms. Keep the container tightly closed in a dry, well-ventilated place.
- Wear safety glasses to EN166 and gloves that pass ASTM F-1671 for dry particulate or an aqueous suspension, plus impervious clothing.
Mitigations
- Examine and test local exhaust ventilation plant at least every 14 months, and keep a record of each check.
Supply and geography
How common the raw materials are and where they come from.
Natural graphite (feedstock for graphite oxide)
USGS gives China 100000000 t of graphite reserves in its 2025 table; world reserve total is not in the excerpt read.
- Top producers (2025)
- China 82%
Natural graphite imports to the United States
US net import reliance for natural graphite is 100 percent.
- Top producers (2024)
- China 46%, Canada 13%, Mozambique 13%, Mexico 12%
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: graphene-oxide
spore_version: 0.2
family: carbon-materials
name: Graphene oxide and reduced graphene oxide
abbreviation: GO, rGO
role: Oxidised graphene sheet (GO) and its reduced form (rGO), used as membranes, composites and coatings
category: carbon
type: Graphene
summary: |
Graphene oxide (GO) is a graphene sheet carrying oxygen groups (epoxy, hydroxyl, carbonyl and carboxyl), made by oxidising graphite. It sits in the same category and type as graphene, but it is not graphene: the oxygen groups make GO an electrical insulator, lower its heat conduction and let it disperse in water. Reduced graphene oxide (rGO) has had some of those groups removed and conducts electricity far better, though still much less than graphene. The values come from a 2019 review, a 2026 review, a 2012 membrane paper, a USGS report, a supplier safety data sheet, HSE guidance and an encyclopedia entry, all read in this run.
best_for: Water-permeable membranes, polymer composites and films where an insulating or water-dispersible carbon sheet is wanted
weakest_at: 'Electrical and thermal performance: GO is an insulator, and reduced GO depends on the reduction route, so no single value describes it'
identity:
formula: Carbon sheet with variable epoxy, hydroxyl, carbonyl and carboxyl groups; no fixed formula
cas: ''
crystal_system: Two-dimensional sheet, usually stacked; no fixed crystal system
space_group: ''
source: go-synthesis
where: Introduction, passage on GO structure with oxygen groups in variable ratios
tags:
environments: []
stresses: []
applications:
- structures
- thermal-control
- electronics-and-chips
- habitats-and-suits
properties:
- benchmark: elastic_modulus
label: Young's modulus, bulk GO paper
value: 6
value_high: 42
bound: range
unit: GPa
scope: material
conditions:
basis: GO paper (stacked sheets); range printed in the review for different oxidation degrees and thicknesses
test: not stated in the review
method: Range quoted in an open-access review, which cites ref 13 of that review
status: ground
source: huang2019
where: Introduction, paragraph on mechanical properties of GO
- benchmark: ultimate_tensile_strength
label: Tensile strength, bulk GO paper (the review calls it intrinsic strength)
value: 76
value_high: 293
bound: range
unit: MPa
scope: material
conditions:
basis: GO paper (stacked sheets); range printed in the review
method: Range quoted in the review, in the same paragraph as the modulus
status: ground
source: huang2019
where: Introduction, paragraph on mechanical properties of GO
- benchmark: elastic_modulus
label: Young's modulus, GO monolayer (review value)
value: 250
unit: GPa
scope: material
conditions:
basis: GO monolayer; printed as 250 ± 150 GPa
test: not stated in the review
method: Value quoted in the review, citing ref 11 of that review
status: ground
note: The printed spread is ± 150 GPa, so this single value is a wide estimate, not a measured range.
source: huang2019
where: Introduction, paragraph on mechanical properties of GO
- benchmark: intrinsic_strength
label: Intrinsic strength, GO monolayer (review value)
value: 30
value_high: 50
bound: range
unit: GPa
scope: material
conditions:
basis: GO monolayer; range printed in the review, paired with the monolayer modulus above
method: Range quoted in the review, citing ref 11 of that review
status: ground
note: Snake-case name, not in the property canon; see gaps.
source: huang2019
where: Introduction, paragraph on mechanical properties of GO
- benchmark: elastic_modulus
label: Young's modulus, GO modified with polyvinyl alcohol
value: 8
unit: GPa
scope: material
conditions:
basis: GO modified with polyvinyl alcohol (ref 133 of the review); the unmodified GO in the same row is 5 GPa
form: modified GO film or paper; form not stated in the row
method: Value printed in Table 1 of the review
status: ground
source: huang2019
where: Table 1 (Young's modulus and tensile strength of GO modified by ions and molecules), row polyvinyl alcohol, ref 133
- benchmark: ultimate_tensile_strength
label: Tensile strength, GO modified with polyvinyl alcohol
value: 125
unit: MPa
scope: material
conditions:
basis: GO modified with polyvinyl alcohol (ref 133 of the review); the unmodified GO in the same row is 25 MPa
method: Value printed in Table 1 of the review
status: ground
source: huang2019
where: Table 1 (Young's modulus and tensile strength of GO modified by ions and molecules), row polyvinyl alcohol, ref 133
- benchmark: elastic_modulus
label: Out-of-plane Young's modulus, conventional GO at 25 percent relative humidity
value: 35
unit: GPa
scope: material
conditions:
basis: conventional porous GO at relative humidity 25 percent, out-of-plane direction
method: Experimental value quoted in the review and matched by DFT with intercalated water
status: ground
note: Printed as 35 ± 10 GPa at ambient humidity. The modulus changes with humidity, so it is not a fixed value.
source: huang2019
where: Section on out-of-plane elasticity, text on conventional GO at RH 25 percent (Fig. 13)
- benchmark: electrical_conductivity
label: Electrical conductivity, GO (lowest value cited)
value: 0.0486
unit: S/m
scope: material
conditions:
basis: GO; the review gives this as the lowest GO conductivity it cites
test: sample form and method not stated
method: Value quoted in an open-access 2026 review
status: ground
source: monir2026
where: Section 2.1 (electrical properties of GO and rGO)
- benchmark: electrical_conductivity
label: Electrical conductivity, rGO monolayer after chemical reduction
value: 0.052
unit: S/m
scope: material
conditions:
basis: chemically reduced rGO monolayer on a silicon substrate, room temperature (298 K)
method: Value quoted in the review, citing Gomez-Navarro et al. (ref 189 of the review)
status: ground
note: The review says this is still about three orders of magnitude below pristine graphene.
source: huang2019
where: Section on electronic transport of GO and RGO (Fig. 23a)
- benchmark: electrical_conductivity
label: Electrical conductivity, rGO reduced by Shewanella
value: 55.32
unit: S/m
scope: material
conditions:
basis: rGO made by microbial reduction with Shewanella oneidensis
method: Value quoted in an open-access 2026 review
status: ground
source: monir2026
where: Section 2.1 (electrical properties of rGO)
- benchmark: electrical_conductivity
label: Electrical conductivity, rGO reduced by hydrazine (comparison case)
value: 216.56
unit: S/m
scope: material
conditions:
basis: rGO made by hydrazine reduction, quoted as the comparison case in the review
method: Value quoted in an open-access 2026 review
status: ground
source: monir2026
where: Section 2.1 (electrical properties of rGO), hydrazine comparison
- benchmark: thermal_conductivity
label: Thermal conductivity, GO and rGO papers or thin films (upper bound)
value: 10
bound: upper
unit: W/(m·K)
scope: material
conditions:
basis: GO or rGO paper or thin film; test temperature not stated in the review
method: Statement in the review, citing two experimental papers (refs 316 and 317 of the review)
status: ground
note: The review attributes the low value to phonon scattering at the junctions between GO nanoplatelets.
source: huang2019
where: Thermal properties section, opening paragraph on GO and RGO papers
- benchmark: thermal_conductivity
label: Thermal conductivity, epoxy-functionalised GO (simulation)
value: 35
unit: W/(m·K)
scope: material
conditions:
basis: GO with epoxy groups at O:C ratio 0.1, sample length 300 nm
method: Non-equilibrium molecular dynamics result quoted in the review; a simulation, not a measurement
status: calculated
source: huang2019
where: Thermal properties section, NEMD results at O:C 0.1 and L = 300 nm
- benchmark: thermal_conductivity
label: Thermal conductivity, hydroxyl-functionalised GO (simulation)
value: 85
unit: W/(m·K)
scope: material
conditions:
basis: GO with hydroxyl groups at O:C ratio 0.1, sample length 300 nm
method: Non-equilibrium molecular dynamics result quoted in the review; a simulation, not a measurement
status: calculated
source: huang2019
where: Thermal properties section, NEMD results at O:C 0.1 and L = 300 nm
- benchmark: thermal_conductivity
label: Thermal conductivity, ether-functionalised GO (simulation)
value: 29
unit: W/(m·K)
scope: material
conditions:
basis: GO with ether groups at O:C ratio 0.1, sample length 300 nm
method: Non-equilibrium molecular dynamics result quoted in the review; a simulation, not a measurement
status: calculated
source: huang2019
where: Thermal properties section, NEMD results at O:C 0.1 and L = 300 nm
- benchmark: interlayer_distance
label: Interlayer distance of a GO membrane
value: 10
unit: Å
scope: material
conditions:
basis: GO membrane as printed (about 10 Å); hydration state not stated
method: X-ray analysis, as stated in the paper
status: ground
note: Snake-case name, not in the property canon; see gaps. Printed as approximately 10 Å.
source: nair2012
where: Results, paragraph on annealed GO membranes (Fig. 2a)
- benchmark: interlayer_distance
label: Interlayer distance of GO after annealing at 300 C in hydrogen and argon
value: 4
unit: Å
scope: material
conditions:
basis: GO annealed at 300 C in a hydrogen and argon atmosphere; printed as about 4 Å for reduced GO
method: X-ray analysis, as stated in the paper
status: ground
note: The same annealing made the membranes about 100 times less permeable to water.
source: nair2012
where: Results, paragraph on annealed GO membranes (Fig. 2a)
- benchmark: thermal_decomposition
label: Temperature above which GO oxygen groups decompose
value: 1000
bound: lower
unit: K
scope: material
conditions:
basis: thermodynamic stability limit for the oxygen groups, as stated in the review
method: Statement in the review
status: ground
note: Snake-case name, not in the property canon. The review gives a stated limit, not a measured onset.
source: huang2019
where: Section 2.1 (thermodynamic and kinetic stabilities)
- benchmark: c_o_ratio
label: C/O ratio of rGO reduced with hydrazine
value: 9.82
unit: '-'
scope: material
conditions:
basis: rGO made by hydrazine reduction; ratio as printed
method: Value printed in the review text on chemical reduction
status: ground
note: A higher C/O ratio means fewer oxygen groups. The review gives no numeric C/O ratio for untreated GO.
source: monir2026
where: Section 3.1.1 (chemical reduction of GO)
corrosion:
- environment: Water and humidity (hydration and ageing)
headline: Water content changes GO stiffness and layer spacing
effect: The review says the out-of-plane stiffness of conventional GO depends on intercalated water, peaking near RH 25 percent. It also says ageing of GO gathers oxygen groups into highly oxidised domains, so the material changes over time. No ageing rate, time or temperature was read in a source.
rating: unknown
conditions:
basis: qualitative statements in the review; no exposure time or temperature stated
source: huang2019
where: Section 2.1 (ageing statement) and out-of-plane elasticity section
- environment: Water (aqueous dispersion)
headline: GO disperses in water; rGO tends to restack
effect: The review says GO forms stable colloidal dispersions in water because its oxygen groups make it highly reactive and hydrophilic. Reduced GO has a strong tendency to agglomerate and restack in aqueous solution.
rating: unknown
conditions:
basis: qualitative statements in the review; dispersion concentration not stated
source: monir2026
where: Section 2.4
- environment: Heat above about 1000 K
headline: Oxygen groups break down at high temperature
effect: The review says the oxygen-containing groups decompose above about 1000 K, and that thermal exfoliation of graphite oxide needs a suggested minimum of 550 C to give RGO. The groups break down into gases during that step.
rating: moderate
conditions:
basis: decomposition of oxygen groups; no heating time or atmosphere stated
source: huang2019
where: Section 2.1 and synthesis section (thermal exfoliation)
risks:
hazards:
- text: A supplier safety data sheet for a 0.5 mg/mL graphene oxide dispersion in water classifies it under OSHA HCS as eye irritation (Category 2A, H319) and respiratory system (H335), with the signal word None.
ghs:
- H319
- H335
source: samaterials-sds
where: Section 2 (hazards identification)
- text: The same sheet lists CNT and graphite CAS numbers in its composition section, so the CAS number of the product itself is not established. Check the sheet for the exact product you handle.
ghs: []
source: samaterials-sds
where: Section 3 (composition)
- text: No UK statutory workplace exposure limit is set for nanomaterials. HSE says the ACGIH threshold for graphite (2 mg/m3 respirable dust) is not an appropriate limit for graphene, and treats nanomaterials as substances of high concern.
ghs: []
source: hsg272
where: Workplace exposure limits section, paragraphs 25 to 27; paragraph 38
failure_risks:
- mode: Oxygen groups decompose on heating
trigger: Heating above about 1000 K
consequence: The oxygen groups break down, so the material is no longer GO in its as-made form. A design that relies on the as-made oxygen content will fail.
severity: moderate
source: huang2019
where: Section 2.1 (thermodynamic and kinetic stabilities)
- mode: Membrane becomes fragile and much less permeable after annealing
trigger: Annealing GO membranes at 300 C in hydrogen and argon
consequence: The membranes became fragile and needed care to avoid cracks, and became about 100 times less permeable to water.
severity: moderate
source: nair2012
where: Results, paragraph on annealed GO membranes (Fig. 2a)
- mode: Stiffness shifts with humidity
trigger: Change in relative humidity or water content
consequence: The out-of-plane modulus of conventional GO depends on water content, with a maximum near RH 25 percent, so a film's stiffness is not fixed.
severity: low
source: huang2019
where: Section on out-of-plane elasticity
side_effects:
- text: During thermal exfoliation the epoxy and hydroxyl groups decompose into gases, and a suggested minimum of 550 C is needed for the product to be RGO.
affects: Sheet size and yield of the product
source: huang2019
where: Synthesis section, thermal exfoliation paragraph
- text: Reduced GO has a strong tendency to agglomerate and restack in water, so its dispersions can lose their state.
affects: Processing of dispersions and films
source: monir2026
where: Section 2.4
handling:
- text: Keep dust-generating work under local exhaust ventilation, and where possible keep the material wet or damp or use slurries.
source: hsg272
where: Good practice section (wet handling) and LEV section
- text: Weigh powders over a damp sheet of absorbent material, and wipe spills with a damp sheet rather than dry sweeping.
source: hsg272
where: Good practice section on weighing and spillages
- text: Avoid dust formation and provide exhaust ventilation where dust forms. Keep the container tightly closed in a dry, well-ventilated place.
source: samaterials-sds
where: Sections 7 and 6
- text: Wear safety glasses to EN166 and gloves that pass ASTM F-1671 for dry particulate or an aqueous suspension, plus impervious clothing.
source: samaterials-sds
where: Section 8 (personal protection)
mitigations:
- text: Examine and test local exhaust ventilation plant at least every 14 months, and keep a record of each check.
source: hsg272
where: LEV section (examination and testing paragraph)
uses:
- application: structures
device: GO and polyvinyl alcohol composite (laboratory)
example: In the review's Table 1, GO modified with polyvinyl alcohol (ref 133) has a Young's modulus of 8 GPa against 5 GPa for the unmodified GO in the same row, and a tensile strength of 125 MPa against 25 MPa.
source: huang2019
where: Table 1, row polyvinyl alcohol, ref 133
- application: electronics-and-chips
device: Reduced GO films as transparent conductors and in field-effect transistors (research)
example: The review lists transparent and flexible conductors and field-effect transistors among the device applications of GO and reduced GO. These are research demonstrations, not product uses.
source: huang2019
where: Abstract, list of device applications
- application: thermal-control
device: GO and rGO films as low-conductivity thermal layers (research)
example: The review cites GO and rGO papers and films below 10 W/(m·K), and names thermoelectric materials as a use that needs suppressed heat conduction.
source: huang2019
where: Thermal properties section; abstract (thermoelectrics)
- application: habitats-and-suits
device: GO laminate membrane for water separation (laboratory test, not a space system)
example: In a laboratory test, GO membranes stopped helium while letting water permeate at least 10^10 times faster than helium. The paper does not address space or life-support use.
source: nair2012
where: Abstract
supply:
- subject: Natural graphite (feedstock for graphite oxide)
abundance: USGS gives China 100000000 t of graphite reserves in its 2025 table; world reserve total is not in the excerpt read.
producers:
- country: China
share_percent: 82
year: 2025
note: share of world natural graphite production, 2025 estimate
critical_lists: []
import_reliance: 100 percent of US apparent consumption (2021 to 2025e)
source: usgs-graphite-2026
where: 'Mineral Commodity Summaries 2026, Graphite (Natural): Events, Trends and Issues; World Mine Production and Reserves table; Salient Statistics'
- subject: Natural graphite imports to the United States
abundance: US net import reliance for natural graphite is 100 percent.
producers:
- country: China
share_percent: 46
year: 2024
note: 2021 to 2024 import share
- country: Canada
share_percent: 13
year: 2024
note: 2021 to 2024 import share
- country: Mozambique
share_percent: 13
year: 2024
note: 2021 to 2024 import share
- country: Mexico
share_percent: 12
year: 2024
note: 2021 to 2024 import share
critical_lists: []
source: usgs-graphite-2026
where: 'Mineral Commodity Summaries 2026, Graphite (Natural): Import Sources (2021 to 2024)'
media: []
documents:
- title: Physical properties and device applications of graphene oxide (arXiv:1912.07956)
type: paper
url: https://arxiv.org/pdf/1912.07956
year: 2019
- title: Unimpeded permeation of water through helium-leak-tight graphene-based membranes (Science 335, 442, arXiv:1112.3488)
type: paper
url: https://arxiv.org/pdf/1112.3488
year: 2012
- title: 'Towards greener reduced graphene oxide: a critical review of environmentally driven reduction strategies (RSC Advances 16, 2044, PMC12776586)'
type: paper
url: https://pmc.ncbi.nlm.nih.gov/articles/PMC12776586/
year: 2026
- title: Structure and Synthesis of graphene oxide (arXiv:1901.02274)
type: paper
url: https://arxiv.org/pdf/1901.02274
year: 2019
- title: 'USGS Mineral Commodity Summaries 2026: Graphite (Natural)'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-graphite.pdf
year: 2026
- title: 'Stanford Advanced Materials safety data sheet: Graphene Oxide Dispersion (0.5 mg/mL in water)'
type: sds
url: https://samaterials.com/tds/1697119733-178-graphene-oxide-05mgml-dispersion-in-water-sds.pdf
year: 2022
- title: 'HSE HSG272: Using nanomaterials at work'
type: report
url: https://www.hse.gov.uk/pubns/books/hsg272.pdf
year: 2013
gaps:
- No product datasheet for GO or rGO was read with a stated C/O ratio, sheet resistance, lateral size or layer count. Commercial values are not included.
- No numeric C/O ratio for untreated GO was read in a fetched source. The review gives O:C ratios only as simulation inputs.
- Thermal conductivity of GO papers was not given at a stated temperature in the fetched text.
- Oxidation temperature in air (thermogravimetry) for GO or rGO was not read from a fetched primary source.
- Ageing and shelf life of GO powder, paste and dispersion were not quantified in any fetched source. The review gives only qualitative ageing statements.
- Radiation, atomic-oxygen, vacuum and thermal-cycling tests of GO or rGO were not found. The space use is not established.
- No corrosion test of GO on metal or on a current collector was found.
- No PubChem compound record for graphene oxide was found. Search results gave vendor pages and the elemental carbon entry (CID 5462310), which are not used. PubChem GHS classification was not read.
- The CAS number of GO is not established. The Stanford sheet's composition section lists CNT and graphite CAS numbers, so it was not used for a CAS value.
- Supply of the Hummers oxidants (sulfuric acid, potassium permanganate, sodium nitrate) and of hydrazine was not read. No critical-mineral status for graphite was read in this run.
- 'Non-canonical property names used: electrical_conductivity, intrinsic_strength, interlayer_distance, thermal_decomposition and c_o_ratio. None is in spores/property-canon.yaml.'
- Two reduction results from the 2026 review's search snippets (Guex 2017, NaBH4 with C/O from 2.2 to 6.9; Compton 2011, solvent-dependent reduction) were not opened, so their numbers are not used.
- Water-permeation result (Nair 2012) is a laboratory membrane test. No space or life-support test was found.
- Recipe process details rest on the review and the Hummers paper. Reaction conditions for a commercial GO product were not read.
sources:
huang2019:
title: Physical properties and device applications of graphene oxide
id: arXiv:1912.07956; Huang, Liu, Zhou and Zhao
url: https://arxiv.org/pdf/1912.07956
year: 2019
kind: paper
license: arXiv, as listed
nair2012:
title: Unimpeded permeation of water through helium-leak-tight graphene-based membranes
id: Science 335, 442 to 444 (2012); arXiv:1112.3488; Nair, Wu, Jayaram, Grigorieva and Geim
url: https://arxiv.org/pdf/1112.3488
year: 2012
kind: paper
license: arXiv, as listed
monir2026:
title: 'Towards greener reduced graphene oxide: a critical review of environmentally driven reduction strategies'
id: RSC Advances 16(3), 2044 to 2061; PMC12776586
url: https://pmc.ncbi.nlm.nih.gov/articles/PMC12776586/
year: 2026
kind: paper
license: CC BY 3.0 (as printed on the page)
go-synthesis:
title: Structure and Synthesis of graphene oxide
id: arXiv:1901.02274
url: https://arxiv.org/pdf/1901.02274
year: 2019
kind: paper
license: arXiv, as listed
usgs-graphite-2026:
title: 'Mineral Commodity Summaries 2026: Graphite (Natural)'
id: USGS MCS 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-graphite.pdf
year: 2026
kind: report
license: public domain (US government)
samaterials-sds:
title: Safety data sheet, Graphene Oxide Dispersion (0.5 mg/mL in water), Stanford Advanced Materials
id: Revised 03/12/2022
url: https://samaterials.com/tds/1697119733-178-graphene-oxide-05mgml-dispersion-in-water-sds.pdf
year: 2022
kind: datasheet
license: supplier document, linked not reproduced
hsg272:
title: Using nanomaterials at work, including carbon nanotubes (CNTs) and other biopersistent high aspect ratio nanomaterials (HARNs), HSG272
id: HSE HSG272
url: https://www.hse.gov.uk/pubns/books/hsg272.pdf
year: 2013
kind: report
license: Open Government Licence
wiki-graphite-oxide:
title: Graphite oxide (Wikipedia), used for composition and history only
id: Wikipedia article Graphite oxide
url: https://en.wikipedia.org/wiki/Graphite_oxide
year: 2026
kind: web
license: CC BY-SA 4.0 (Wikipedia)
license: CC-BY-4.0
updated: '2026-10-26'
review:
status: draft
method: assistant
checked_values: 19
unreachable: 2
caveats: 3
note: 'Written by an assistant on 2026-10-26 from pages read in this run: arXiv 1912.07956, arXiv 1112.3488, PMC12776586, arXiv 1901.02274, USGS MCS 2026 graphite, the Stanford Advanced Materials SDS, HSE HSG272 and Wikipedia (composition and history only). Search snippets were not used as values. Commercial GO and rGO products were not verified.'
story:
recipe:
line: Graphene oxide is made by oxidising graphite, usually with the Hummers method (sulfuric acid and potassium permanganate), and then exfoliating the oxidised graphite in water. The sheet keeps a carbon lattice with epoxy bridges, hydroxyl groups on its faces, and carbonyl and carboxyl groups at its edges. Reduced graphene oxide has lost some of those groups, for example by thermal exfoliation at a suggested minimum of 550 C or by chemical reduction with hydrazine.
parts:
- name: Carbon
symbol: C
role: Forms the sheet. Oxidised areas hold carbon bonded to oxygen, which breaks the flat sp2 lattice locally.
- name: Oxygen
symbol: O
role: Sits in epoxy bridges, hydroxyl, carbonyl and carboxyl groups. Its amount sets the C/O ratio and how far the conductivity is suppressed.
- name: Hydrogen
symbol: H
role: Sits on hydroxyl and carboxyl groups. Hydrogen species in as-made GO are thought to make the film metastable, according to the review.
risk_groups:
- title: For people
level: 1
verdict: Handle as a precaution
lead: The supplier sheet for a dispersion classifies it as an eye and airway irritant, and no exposure limit is set for graphene oxide.
points:
- label: Eyes and airways
line: A supplier sheet for a 0.5 mg/mL dispersion gives serious eye irritation (H319) and respiratory irritation (H335), with no signal word.
- label: Dust
line: Keep dust out of the air with local exhaust ventilation. HSE says nanomaterials are substances of high concern, and graphite's threshold is not an appropriate limit for graphene.
why: Graphene oxide is graphene carrying oxygen groups. The groups make the sheet an electrical insulator and cut its heat conduction, but they also let it disperse in water and bind to other materials. Reduction removes some of the groups and raises conductivity. The useful numbers depend on the oxidation level, the form (paper, film or monolayer) and humidity, so most values here are ranges.
uses:
- where: Polymer composites
line: A review table lists GO modified with polyvinyl alcohol at a Young's modulus of 8 GPa, against 5 GPa for the unmodified GO in the same row. The tensile strength in that row is 125 MPa against 25 MPa.
- where: Membranes
line: In a laboratory test, GO membranes stopped helium while letting water through at least 10^10 times faster than helium. This is a research result and not a space system.
- where: Films and devices
line: The review lists transparent and flexible conductors and field-effect transistors as device applications of GO and reduced GO. These are research demonstrations.
can_do:
- label: Stiffness
benchmark: elastic_modulus
line: Bulk GO paper is cited at 6 to 42 GPa in Young's modulus. A GO monolayer is quoted at 250 GPa, with a printed spread of 150 GPa. Measured values depend on oxidation, water content and test method.
- label: Electrical conduction
benchmark: electrical_conductivity
line: 'GO is an insulator, cited as low as 0.0486 S/m. Reduction raises the value: 0.052 S/m for a reduced monolayer, 55.32 S/m for a Shewanella-reduced rGO, and 216.56 S/m for a hydrazine-reduced rGO used as the comparison.'
- label: Heat conduction
benchmark: thermal_conductivity
line: GO and rGO papers and films are cited below 10 W/(m·K). Simulations at an O:C ratio of 0.1 give 35, 85 and 29 W/(m·K) for epoxy, hydroxyl and ether groups, which are not measurements.
- label: Water permeation
benchmark: interlayer_distance
line: GO membranes let water through much faster than helium. Annealing at 300 C in hydrogen and argon shrinks the interlayer distance from about 10 Å to about 4 Å and makes the membrane about 100 times less permeable to water.
compare: Graphene oxide and reduced graphene oxide are not graphene. Graphene is quoted in the review at 1 TPa in stiffness and with far higher thermal conduction at room temperature, both for ideal sheets. GO has oxygen on those sheets, so its electrical conductivity drops to 0.0486 S/m as the lowest value cited, and its films conduct heat below 10 W/(m·K). Reduction recovers some conductivity, to between 0.052 and 216.56 S/m across the cited cases, depending on the reductant. The comparison is with graphene's ideal values, not with a commercial graphene product.
compare_rows:
- label: Electrical conductivity
benchmark: electrical_conductivity
- label: Young's modulus
benchmark: elastic_modulus
- label: Thermal conductivity
benchmark: thermal_conductivity
handling:
- Keep dust-generating work under local exhaust ventilation, and keep powders damp or in slurry where possible.
- Wipe spills with a damp sheet, and weigh powders over a damp sheet. Do not dry sweep.
- Wear safety glasses, gloves that pass ASTM F-1671, and impervious clothing. Check the supplier sheet for the product you use.
good_for:
- Water-permeable membranes and laminates at laboratory stage, where a gas-tight but water-passing layer is the goal.
- 'Polymer composites: the review''s polyvinyl alcohol example raises Young''s modulus from 5 GPa to 8 GPa.'
- Low-conductivity films where heat must not spread, such as thermoelectric research.
watch_out:
- Pure GO is electrically insulating. Reduction changes conductivity by orders of magnitude, and the result depends on the reductant.
- Stiffness and strength values span wide ranges. The monolayer value of 250 GPa carries a printed spread of 150 GPa.
- Humidity changes the out-of-plane stiffness and the layer spacing, so properties drift with moisture.
- Above about 1000 K the oxygen groups decompose, which changes the material.
verdict: GO suits laboratory work on water-permeable membranes and polymer composites. For electrical and thermal use, the reduction route and the form decide the result. No space or flight data were found.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Physical properties and device applications of graphene oxide | paper | 2019 | 21 values | |
| Unimpeded permeation of water through helium-leak-tight graphene-based membranes | paper | 2012 | 4 values | |
| Towards greener reduced graphene oxide: a critical review of environmentally driven reduction strategies | paper | 2026 | 6 values | |
| Structure and Synthesis of graphene oxide | paper | 2019 | 1 value | |
| Mineral Commodity Summaries 2026: Graphite (Natural) | report | 2026 | 2 values | |
| Safety data sheet, Graphene Oxide Dispersion (0.5 mg/mL in water), Stanford Advanced Materials | datasheet | 2022 | 4 values | |
| Using nanomaterials at work, including carbon nanotubes (CNTs) and other biopersistent high aspect ratio nanomaterials (HARNs), HSG272 | report | 2013 | 4 values | |
| Graphite oxide (Wikipedia), used for composition and history only | web | 2026 | 0 values |