Patent
US 9,637,443GRAPHENE QUANTUM DOTS AND METHOD OF MAKING
Julia Xiaojun Zhao
US
Copyright © 2026 Matter42. All rights reserved.
Patent
Atlas literature
Patent
US 9,637,443Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 2 illustrates fluorescence emission spectra of GQDs produced from maltose. [0011]
FIG. 3 illustrates fluorescence emission spectra of GQDs produced from glucose. [0012]
FIG. 4 illustrates fluorescence emission spectra of GQDs produced from tyrosine. [0013]
FIG. 5 illustrates fluorescence emission spectra of GQDs produced from sucrose. [0014]
FIG. 6 illustrates fluorescence emission spectra of GQDs produced from galactose. [0015]
FIG. 7 illustrates fluorescence emission spectra of GQDs produced from glutamic acid according to
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 11 illustrates the photostability of FITC and GQDs formed according to
FIG. 12 illustrates the fluorescence intensity of GQDs formed according to
FIG. 13B. Similar to the fluorescence property in the visible region, the peak in the NIR region showed red shift when the excitation wavelength was increased. …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
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 for forming [[a]] graphene quantum dots comprising: adding an organic amino acid starting material to a vessel, wherein the organic starting material is a hydrophilic compound comprising a plurality of functional groups selected from the group consisting of carboxyl groups and hydroxyl groups; and heating the organic amino acid starting material to a temperature that is within 20 ° C of the organic starting material ' s boiling temperature in the absence of a solvent for a time no longer than ten minutes to pyrolyze the amino acid starting material and form graphene quantum dots.
The method of claim 1, further comprising: adding a solvent to the graphene quantum dots to form a colloidal solution containing graphene quantum dots; mixing the solution for between 15 minutes and 60 minutes; and centrifuging the solution after mixing to obtain a supernatant comprising a concentrated grap hene q uantum dot p roduct.
The method of claim 1, wherein the organic amino acid starting material is heated for a time less than five minutes.
The method of claim 1, wherein the organic amino acid starting material is heated until the organic amino acid starting material changes from a substantially colorless solution to a solution having a yellow color.
The method of claim 1, wherein the organic amino acid starting material comprises glutamic acid, and wherein the organic starting material is heated to a temperature of about 210 °C.
The method of claim 1, wherein the graphene quantum dots have an average diameter between 1 nanometer and 7 nanometers.
The method of claim 1, wherein the graphene quantum dots comprise: between 55% and 65% carbon atoms; between 30% and 40% oxygen atoms; and between 3.5% and 7.5% nitrogen atoms.
(Ori g ina l) The method of claim 1. wherein the graphene quantum dots comprise nitrogen atoms at a level between 6.0% and 11.0% of a level of carbon atoms present in the graphene quantum dots.
The method of claim 1, wherein the graphene quantum dots are capable of catalyzing reduction of hydrogen peroxide.
canceled
The method of claim [[2]] 1, wherein the organic amino acid starting material is selected from the group consisting of glutamic acid, aspartic acid, tyrosine, serine, threonine, maltose asparagine, glucose glutamine, sucrose alanine, galactose glycine, lactose leucine, fructose lysine and combinations thereof.
canceled
15-25. canceled
Materials described outside the worked examples.
graphene quantum dots
organic amino acid starting material
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
average diameter of Glu-GQDs | 1–7 nm | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
carbon atom content of graphene quantum dots | 55–65 at% |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 9,637,443Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 2 illustrates fluorescence emission spectra of GQDs produced from maltose. [0011]
FIG. 3 illustrates fluorescence emission spectra of GQDs produced from glucose. [0012]
FIG. 4 illustrates fluorescence emission spectra of GQDs produced from tyrosine. [0013]
FIG. 5 illustrates fluorescence emission spectra of GQDs produced from sucrose. [0014]
FIG. 6 illustrates fluorescence emission spectra of GQDs produced from galactose. [0015]
FIG. 7 illustrates fluorescence emission spectra of GQDs produced from glutamic acid according to
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 11 illustrates the photostability of FITC and GQDs formed according to
FIG. 12 illustrates the fluorescence intensity of GQDs formed according to
FIG. 13B. Similar to the fluorescence property in the visible region, the peak in the NIR region showed red shift when the excitation wavelength was increased. …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
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 for forming [[a]] graphene quantum dots comprising: adding an organic amino acid starting material to a vessel, wherein the organic starting material is a hydrophilic compound comprising a plurality of functional groups selected from the group consisting of carboxyl groups and hydroxyl groups; and heating the organic amino acid starting material to a temperature that is within 20 ° C of the organic starting material ' s boiling temperature in the absence of a solvent for a time no longer than ten minutes to pyrolyze the amino acid starting material and form graphene quantum dots.
The method of claim 1, further comprising: adding a solvent to the graphene quantum dots to form a colloidal solution containing graphene quantum dots; mixing the solution for between 15 minutes and 60 minutes; and centrifuging the solution after mixing to obtain a supernatant comprising a concentrated grap hene q uantum dot p roduct.
The method of claim 1, wherein the organic amino acid starting material is heated for a time less than five minutes.
The method of claim 1, wherein the organic amino acid starting material is heated until the organic amino acid starting material changes from a substantially colorless solution to a solution having a yellow color.
The method of claim 1, wherein the organic amino acid starting material comprises glutamic acid, and wherein the organic starting material is heated to a temperature of about 210 °C.
The method of claim 1, wherein the graphene quantum dots have an average diameter between 1 nanometer and 7 nanometers.
The method of claim 1, wherein the graphene quantum dots comprise: between 55% and 65% carbon atoms; between 30% and 40% oxygen atoms; and between 3.5% and 7.5% nitrogen atoms.
(Ori g ina l) The method of claim 1. wherein the graphene quantum dots comprise nitrogen atoms at a level between 6.0% and 11.0% of a level of carbon atoms present in the graphene quantum dots.
The method of claim 1, wherein the graphene quantum dots are capable of catalyzing reduction of hydrogen peroxide.
canceled
The method of claim [[2]] 1, wherein the organic amino acid starting material is selected from the group consisting of glutamic acid, aspartic acid, tyrosine, serine, threonine, maltose asparagine, glucose glutamine, sucrose alanine, galactose glycine, lactose leucine, fructose lysine and combinations thereof.
canceled
15-25. canceled
Materials described outside the worked examples.
graphene quantum dots
organic amino acid starting material
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
average diameter of Glu-GQDs | 1–7 nm | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
carbon atom content of graphene quantum dots | 55–65 at% |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 9,637,443Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 2 illustrates fluorescence emission spectra of GQDs produced from maltose. [0011]
FIG. 3 illustrates fluorescence emission spectra of GQDs produced from glucose. [0012]
FIG. 4 illustrates fluorescence emission spectra of GQDs produced from tyrosine. [0013]
FIG. 5 illustrates fluorescence emission spectra of GQDs produced from sucrose. [0014]
FIG. 6 illustrates fluorescence emission spectra of GQDs produced from galactose. [0015]
FIG. 7 illustrates fluorescence emission spectra of GQDs produced from glutamic acid according to
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 11 illustrates the photostability of FITC and GQDs formed according to
FIG. 12 illustrates the fluorescence intensity of GQDs formed according to
FIG. 13B. Similar to the fluorescence property in the visible region, the peak in the NIR region showed red shift when the excitation wavelength was increased. …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
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 for forming [[a]] graphene quantum dots comprising: adding an organic amino acid starting material to a vessel, wherein the organic starting material is a hydrophilic compound comprising a plurality of functional groups selected from the group consisting of carboxyl groups and hydroxyl groups; and heating the organic amino acid starting material to a temperature that is within 20 ° C of the organic starting material ' s boiling temperature in the absence of a solvent for a time no longer than ten minutes to pyrolyze the amino acid starting material and form graphene quantum dots.
The method of claim 1, further comprising: adding a solvent to the graphene quantum dots to form a colloidal solution containing graphene quantum dots; mixing the solution for between 15 minutes and 60 minutes; and centrifuging the solution after mixing to obtain a supernatant comprising a concentrated grap hene q uantum dot p roduct.
The method of claim 1, wherein the organic amino acid starting material is heated for a time less than five minutes.
The method of claim 1, wherein the organic amino acid starting material is heated until the organic amino acid starting material changes from a substantially colorless solution to a solution having a yellow color.
The method of claim 1, wherein the organic amino acid starting material comprises glutamic acid, and wherein the organic starting material is heated to a temperature of about 210 °C.
The method of claim 1, wherein the graphene quantum dots have an average diameter between 1 nanometer and 7 nanometers.
The method of claim 1, wherein the graphene quantum dots comprise: between 55% and 65% carbon atoms; between 30% and 40% oxygen atoms; and between 3.5% and 7.5% nitrogen atoms.
(Ori g ina l) The method of claim 1. wherein the graphene quantum dots comprise nitrogen atoms at a level between 6.0% and 11.0% of a level of carbon atoms present in the graphene quantum dots.
The method of claim 1, wherein the graphene quantum dots are capable of catalyzing reduction of hydrogen peroxide.
canceled
The method of claim [[2]] 1, wherein the organic amino acid starting material is selected from the group consisting of glutamic acid, aspartic acid, tyrosine, serine, threonine, maltose asparagine, glucose glutamine, sucrose alanine, galactose glycine, lactose leucine, fructose lysine and combinations thereof.
canceled
15-25. canceled
Materials described outside the worked examples.
graphene quantum dots
organic amino acid starting material
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
average diameter of Glu-GQDs | 1–7 nm | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
carbon atom content of graphene quantum dots | 55–65 at% |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 9,637,443Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 2 illustrates fluorescence emission spectra of GQDs produced from maltose. [0011]
FIG. 3 illustrates fluorescence emission spectra of GQDs produced from glucose. [0012]
FIG. 4 illustrates fluorescence emission spectra of GQDs produced from tyrosine. [0013]
FIG. 5 illustrates fluorescence emission spectra of GQDs produced from sucrose. [0014]
FIG. 6 illustrates fluorescence emission spectra of GQDs produced from galactose. [0015]
FIG. 7 illustrates fluorescence emission spectra of GQDs produced from glutamic acid according to
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 11 illustrates the photostability of FITC and GQDs formed according to
FIG. 12 illustrates the fluorescence intensity of GQDs formed according to
FIG. 13B. Similar to the fluorescence property in the visible region, the peak in the NIR region showed red shift when the excitation wavelength was increased. …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
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 for forming [[a]] graphene quantum dots comprising: adding an organic amino acid starting material to a vessel, wherein the organic starting material is a hydrophilic compound comprising a plurality of functional groups selected from the group consisting of carboxyl groups and hydroxyl groups; and heating the organic amino acid starting material to a temperature that is within 20 ° C of the organic starting material ' s boiling temperature in the absence of a solvent for a time no longer than ten minutes to pyrolyze the amino acid starting material and form graphene quantum dots.
The method of claim 1, further comprising: adding a solvent to the graphene quantum dots to form a colloidal solution containing graphene quantum dots; mixing the solution for between 15 minutes and 60 minutes; and centrifuging the solution after mixing to obtain a supernatant comprising a concentrated grap hene q uantum dot p roduct.
The method of claim 1, wherein the organic amino acid starting material is heated for a time less than five minutes.
The method of claim 1, wherein the organic amino acid starting material is heated until the organic amino acid starting material changes from a substantially colorless solution to a solution having a yellow color.
The method of claim 1, wherein the organic amino acid starting material comprises glutamic acid, and wherein the organic starting material is heated to a temperature of about 210 °C.
The method of claim 1, wherein the graphene quantum dots have an average diameter between 1 nanometer and 7 nanometers.
The method of claim 1, wherein the graphene quantum dots comprise: between 55% and 65% carbon atoms; between 30% and 40% oxygen atoms; and between 3.5% and 7.5% nitrogen atoms.
(Ori g ina l) The method of claim 1. wherein the graphene quantum dots comprise nitrogen atoms at a level between 6.0% and 11.0% of a level of carbon atoms present in the graphene quantum dots.
The method of claim 1, wherein the graphene quantum dots are capable of catalyzing reduction of hydrogen peroxide.
canceled
The method of claim [[2]] 1, wherein the organic amino acid starting material is selected from the group consisting of glutamic acid, aspartic acid, tyrosine, serine, threonine, maltose asparagine, glucose glutamine, sucrose alanine, galactose glycine, lactose leucine, fructose lysine and combinations thereof.
canceled
15-25. canceled
Materials described outside the worked examples.
graphene quantum dots
organic amino acid starting material
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
average diameter of Glu-GQDs | 1–7 nm | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
carbon atom content of graphene quantum dots | 55–65 at% |
Related documents with shared materials, methods, properties, or citations.
glutamic acid
C₅H₉NO₄
aspartic acid
tyrosine
serine
threonine
maltose
glucose
sucrose
galactose
lactose
fructose
solvent (water, alcohols or combinations)
Glu-GQDs (glutamic acid-derived graphene quantum dots)
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
graphene quantum dots |
oxygen atom content of graphene quantum dots | 30–40 at% | graphene quantum dots |
nitrogen atom content of graphene quantum dots | 3.5–7.5 at% | graphene quantum dots |
nitrogen-to-carbon ratio in graphene quantum dots | 6–11 % | graphene quantum dots |
fluorescence quantum yield of Glu-GQDs relative to citric-acid GQDs | — | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
Temperature | 185–225 °C | — |
Duration | 15–60 minutes | — |
Thickness | 310–380 nm | — |
Thickness | 400–495 nm | — |
Thickness | 800–885 nm | — |
Thickness | 320–540 nm | — |
Thickness | 440–815 nm | — |
Thickness | 0.1–10 mM | — |
Thickness | 330–385 nm | — |
Thickness | 460–500 nm | — |
Thickness | 535–585 nm | — |
Thickness | 565–700 nm | — |
Thickness | 380–650 nm | — |
Thickness | 515–575 nm | — |
Thickness | 575–650 nm | — |
Thickness | 695–770 nm | — |
Duration | ≤ 60 seconds | — |
glutamic acid
C₅H₉NO₄
aspartic acid
tyrosine
serine
threonine
maltose
glucose
sucrose
galactose
lactose
fructose
solvent (water, alcohols or combinations)
Glu-GQDs (glutamic acid-derived graphene quantum dots)
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
graphene quantum dots |
oxygen atom content of graphene quantum dots | 30–40 at% | graphene quantum dots |
nitrogen atom content of graphene quantum dots | 3.5–7.5 at% | graphene quantum dots |
nitrogen-to-carbon ratio in graphene quantum dots | 6–11 % | graphene quantum dots |
fluorescence quantum yield of Glu-GQDs relative to citric-acid GQDs | — | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
Temperature | 185–225 °C | — |
Duration | 15–60 minutes | — |
Thickness | 310–380 nm | — |
Thickness | 400–495 nm | — |
Thickness | 800–885 nm | — |
Thickness | 320–540 nm | — |
Thickness | 440–815 nm | — |
Thickness | 0.1–10 mM | — |
Thickness | 330–385 nm | — |
Thickness | 460–500 nm | — |
Thickness | 535–585 nm | — |
Thickness | 565–700 nm | — |
Thickness | 380–650 nm | — |
Thickness | 515–575 nm | — |
Thickness | 575–650 nm | — |
Thickness | 695–770 nm | — |
Duration | ≤ 60 seconds | — |
glutamic acid
C₅H₉NO₄
aspartic acid
tyrosine
serine
threonine
maltose
glucose
sucrose
galactose
lactose
fructose
solvent (water, alcohols or combinations)
Glu-GQDs (glutamic acid-derived graphene quantum dots)
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
graphene quantum dots |
oxygen atom content of graphene quantum dots | 30–40 at% | graphene quantum dots |
nitrogen atom content of graphene quantum dots | 3.5–7.5 at% | graphene quantum dots |
nitrogen-to-carbon ratio in graphene quantum dots | 6–11 % | graphene quantum dots |
fluorescence quantum yield of Glu-GQDs relative to citric-acid GQDs | — | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
Temperature | 185–225 °C | — |
Duration | 15–60 minutes | — |
Thickness | 310–380 nm | — |
Thickness | 400–495 nm | — |
Thickness | 800–885 nm | — |
Thickness | 320–540 nm | — |
Thickness | 440–815 nm | — |
Thickness | 0.1–10 mM | — |
Thickness | 330–385 nm | — |
Thickness | 460–500 nm | — |
Thickness | 535–585 nm | — |
Thickness | 565–700 nm | — |
Thickness | 380–650 nm | — |
Thickness | 515–575 nm | — |
Thickness | 575–650 nm | — |
Thickness | 695–770 nm | — |
Duration | ≤ 60 seconds | — |
glutamic acid
C₅H₉NO₄
aspartic acid
tyrosine
serine
threonine
maltose
glucose
sucrose
galactose
lactose
fructose
solvent (water, alcohols or combinations)
Glu-GQDs (glutamic acid-derived graphene quantum dots)
FIG. 1 to detect the presence of H202. [0024] FIGs. 15A, 15B, 15C and 15D are graphs illustrating the effect of pH, temperature, ABTS concentration and GQD …
FIG. 8 is a graph showing the size distribution of GQDs formed according to
FIG. 9 illustrates FTIR spectra of glutamic acid (a) and GQDs (b) formed according to
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 10 A illustrates UV-vis absorption spectra and photoluminescence (PL) spectra of Glu-GQDs. The Glu-GQDs showed two obvious absorption peaks at 238 nm and …
FIG. 14 is a UV-vis absorption spectra showing the ability of GQDs formed according to
FIG. 15D). However, a high concentration of Glu- GQDs could affect the absorption of the ABTS. Therefore, a concentration of 5.40 mg/mL Glu- GQDs was chosen as …
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
FIG. 16A is a graph illustrating the change in absorbance relative to the H₂ 02 concentration. [0026]
graphene quantum dots |
oxygen atom content of graphene quantum dots | 30–40 at% | graphene quantum dots |
nitrogen atom content of graphene quantum dots | 3.5–7.5 at% | graphene quantum dots |
nitrogen-to-carbon ratio in graphene quantum dots | 6–11 % | graphene quantum dots |
fluorescence quantum yield of Glu-GQDs relative to citric-acid GQDs | — | Glu-GQDs (glutamic acid-derived graphene quantum dots) |
Temperature | 185–225 °C | — |
Duration | 15–60 minutes | — |
Thickness | 310–380 nm | — |
Thickness | 400–495 nm | — |
Thickness | 800–885 nm | — |
Thickness | 320–540 nm | — |
Thickness | 440–815 nm | — |
Thickness | 0.1–10 mM | — |
Thickness | 330–385 nm | — |
Thickness | 460–500 nm | — |
Thickness | 535–585 nm | — |
Thickness | 565–700 nm | — |
Thickness | 380–650 nm | — |
Thickness | 515–575 nm | — |
Thickness | 575–650 nm | — |
Thickness | 695–770 nm | — |
Duration | ≤ 60 seconds | — |