WO2017032330A1 - 不同含氧量的石墨烯量子点的制备方法、石墨烯量子点和荧光材料 - Google Patents

不同含氧量的石墨烯量子点的制备方法、石墨烯量子点和荧光材料 Download PDF

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WO2017032330A1
WO2017032330A1 PCT/CN2016/096709 CN2016096709W WO2017032330A1 WO 2017032330 A1 WO2017032330 A1 WO 2017032330A1 CN 2016096709 W CN2016096709 W CN 2016096709W WO 2017032330 A1 WO2017032330 A1 WO 2017032330A1
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graphene quantum
quantum dots
graphene
quantum dot
oxygen content
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PCT/CN2016/096709
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French (fr)
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张麟德
张明东
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深圳粤网节能技术服务有限公司
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Priority to US15/744,852 priority Critical patent/US11299671B2/en
Priority to JP2018529705A priority patent/JP6877431B2/ja
Publication of WO2017032330A1 publication Critical patent/WO2017032330A1/zh

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    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/65—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing carbon
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/182—Graphene
    • C01B32/184—Preparation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y40/00—Manufacture or treatment of nanostructures
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/70—Nanostructure
    • Y10S977/734—Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc.
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/70—Nanostructure
    • Y10S977/773—Nanoparticle, i.e. structure having three dimensions of 100 nm or less
    • Y10S977/774—Exhibiting three-dimensional carrier confinement, e.g. quantum dots
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/84—Manufacture, treatment, or detection of nanostructure
    • Y10S977/842—Manufacture, treatment, or detection of nanostructure for carbon nanotubes or fullerenes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/902—Specified use of nanostructure
    • Y10S977/932—Specified use of nanostructure for electronic or optoelectronic application
    • Y10S977/949—Radiation emitter using nanostructure
    • Y10S977/95—Electromagnetic energy

Definitions

  • the invention belongs to the technical field of fluorescent nano materials, and particularly relates to a method for preparing graphene quantum dots with different oxygen contents, graphene quantum dots and fluorescent materials.
  • the perfect graphene has an ideal two-dimensional structure. It consists of a hexagonal lattice. Each carbon atom is bonded to the other three carbon atoms in the plane of the lattice plane through the ⁇ bond. The electrons that are not ⁇ bond are used as ⁇ . The electrons form a ⁇ -orbital system perpendicular to the plane of the lattice. The ⁇ electrons can move freely on the plane.
  • the band structure is in the form of a Dirac cone, and at the Dirac point, the conduction band of the graphene and the valence band coincide, so the electron at its Dirac point
  • the effective mass of the holes and the holes are all zero, and the mobility of the corresponding electrons and holes are the same and infinitely close to infinity, which means that the carrier can be either a hole or an electron, and its carrier mobility is extremely high.
  • the carrier can be either a hole or an electron, and its carrier mobility is extremely high.
  • ideal graphene should have excellent electrical conductivity and is predicted to withstand current densities six orders of magnitude higher than copper.
  • Such graphene has a corresponding energy band gap, which results in a laser emission wavelength formed after the exciton de-excitation is excellent, and has excellent laser characteristics.
  • Such graphene particles have characteristics similar to those of semiconductor quantum dots in inorganic materials, so they are called graphene quantum dots, and the radius of graphene quantum dots is within the Bohr radius, which is non-toxic and harmless.
  • the narrow fluorescence wavelength and wide laser wavelength make it an excellent application for light-emitting diodes (LEDs) and bio-imaging as well as photovoltaic devices and sensors.
  • the technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a method for preparing graphene quantum dots of different oxygen contents.
  • the invention provides a preparation method of graphene quantum dots with different oxygen contents, which comprises the following steps:
  • Step 1 dispersing graphene oxide in a peroxide solution to obtain a graphene oxide dispersion
  • Step 2 mixing the graphene oxide dispersion with an alkali solution and purifying to obtain a graphene quantum dot dry powder
  • Step 3 After loading the graphene quantum dot dry powder on the carrier, gradient elution is performed to obtain graphene quantum dots with different oxygen contents.
  • the graphene oxide has a carbon to oxygen ratio of 0.5 to 5.
  • the graphene oxide dispersion has a mass concentration of graphene oxide of 0.1% to 5%; and/or the mass concentration of the peroxide solution is 3% to 30%.
  • the peroxide is at least one of hydrogen peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, sodium perborate, peroxydibenzoyl or dilauroyl peroxide.
  • the method further comprises the steps of: reacting the purified product with a reducing agent in a solvent, and purifying to obtain a graphene quantum dot dry powder.
  • the gradient elution in the third step is specifically: gradient elution by vacuum liquid chromatography or column chromatography.
  • the eluent used in the gradient elution includes a first polar solvent and a second polar solvent, the first polar solvent having a polarity greater than a polarity of the second polar solvent; the first pole
  • the solvent includes one or more of water, methanol, ethanol, ethylene glycol, hydrochloric acid-methanol solution, tetrahydrofuran, formic acid, acetic acid, acetonitrile, N,N-dimethylformamide, diethyl ether, acetone, and nitromethane.
  • the second polar solvent comprises one or more of cyclohexane, n-hexane, petroleum ether, ethyl acetate, dimethyl carbonate, dichloromethane, chloroform, carbon tetrachloride.
  • the present invention provides a graphene quantum dot having an oxygen content of 2% to 40%.
  • the emission wavelength is from 550 nm to 750 nm.
  • the present invention provides a fluorescent material comprising graphene quantum dots prepared by the above-described method for preparing different oxygen content graphene quantum dots.
  • the invention provides a method for preparing graphene quantum dots with different oxygen content, which firstly disperses graphene oxide in a solution of peroxide to obtain a graphene oxide dispersion; in this step, the peroxide acts as an oxidant. It can be beneficial to form graphene quantum dots with wide oxygen content distribution, which provides a precondition for subsequent obtaining of different oxygen content graphene quantum dots; then, the graphene oxide dispersion liquid is mixed with the alkali liquid to obtain graphene quantum dots. Finally, the graphene quantum dots are loaded and then eluted with a gradient. By changing the polarity of the eluent, the graphene quantum dots with different oxygen contents are obtained after elution.
  • the oxygen content of the graphene quantum dots can be controlled, thereby achieving controllable emission wavelength of the product, and providing reliable use for graphene quantum dots in the fields of LED, cell labeling and the like. Premise.
  • the method provided by the present invention is also simple and easy to operate.
  • Example 1 is an atomic force microscope chart of Sample 1 in Example 1 of the present invention.
  • Example 2 is a fluorescence spectrum diagram of Sample 1 at different excitation wavelengths in Example 1 of the present invention
  • Figure 3 is an atomic force microscope diagram of Sample 3 in Example 2 of the present invention.
  • Figure 4 is an atomic force microscope diagram of Sample 6 in Example 3 of the present invention.
  • Figure 5 is an atomic force microscope diagram of Sample 10 in Example 4 of the present invention.
  • Figure 6 is a normalized fluorescence spectrum of Samples 1 to 5, and Samples 9 to 11 in the examples of the present invention.
  • Embodiments of the present invention provide a method for preparing graphene quantum dots of different oxygen contents, which includes the following steps:
  • Step 1 dispersing graphene oxide in a peroxide solution to obtain a graphene oxide dispersion
  • Step 2 mixing the graphene oxide dispersion with an alkali solution and purifying to obtain a graphene quantum dot dry powder
  • Step 3 After loading the graphene quantum dot dry powder, a gradient elution is performed to obtain graphene quantum dots with different oxygen contents.
  • the first step is a process of preparing a graphene oxide dispersion.
  • the dispersion is preferably performed by ultrasonic dispersion, and further, the ultrasonic dispersion may be carried out for 0.5 h to 2 h.
  • Peroxide is used to form hydroxyl radicals in solution and acts as an oxidizing agent. The present inventors have found that the use of peroxide as an oxidizing agent facilitates the formation of graphene quantum dots having a broad oxygen content distribution, and provides a prerequisite for obtaining graphene quantum dots having different oxygen contents.
  • the peroxide may be an organic peroxide or an inorganic peroxide, and may be, for example, hydrogen peroxide, ammonium persulfate, sodium persulfate, potassium hydrogen persulfate, sodium perborate, or dibenzoyl peroxide. At least one of peroxides such as dilauroyl peroxide. Preferably, the peroxide is at least one of hydrogen peroxide, ammonium persulfate, or dibenzoyl peroxide.
  • the mass concentration of graphene oxide in the prepared graphene oxide dispersion is preferably 0.1 to 5%, and the concentration of graphene oxide is too high, the system compares the cotton, affecting the yield of graphene quantum dots; Low is difficult to collect products.
  • the mass concentration of the peroxide solution is preferably from 3 to 30%. Low peroxide concentration, low yield of graphene quantum dots; peroxide If the concentration is too high, the reaction system is unstable and the heat release is too large.
  • the inventors have also found that the carbon-oxygen ratio of graphene oxide GO has a certain influence on the oxygen content of the final graphene quantum dots, and the larger the carbon-oxygen ratio of the raw materials, the wider the oxygen content distribution of the graphene quantum dots.
  • the graphene oxide may have a carbon to oxygen ratio (C:O) of 0.5 to 5.
  • the graphene oxide has a carbon to oxygen ratio of 1 to 2.
  • Step two is a process of preparing graphene oxide quantum dots.
  • the lye may be an inorganic lye, such as NaOH, KOH, or an organic lye such as ethylenediamine, trimethylamine, n-butylamine, tetramethylammonium hydroxide or the like.
  • the lye is preferably a saturated solution.
  • Step two may be: slowly adding the graphene oxide dispersion to a saturated alkali solution. Further, in order to control the reaction rate and improve the uniformity of the mixing of the raw materials, the above mixing is preferably carried out by dropwise addition, and the lye is brought to a stirring state before the dropwise addition and during the dropwise addition.
  • the graphene oxide is dispersed and dropped into the stirred alkali solution by dropwise addition.
  • the agitation may be mechanical agitation or magnetic agitation, and the rotation speed may be from 60 rpm to 800 rpm.
  • the temperature of the mixed reaction of the graphene oxide dispersion and the saturated alkali solution may be 0 to 120 ° C, and the reaction temperature has a certain influence on the size of the prepared graphene quantum dots. The higher the temperature, the smaller the size. However, the higher the temperature, the more intense the reaction and the less control it is.
  • the reaction temperature is from 20 ° C to 30 ° C.
  • the heating method is preferably a water bath heating or an oil bath heating.
  • the volume ratio of the graphene oxide dispersion to the saturated lye is (10 to 100):1.
  • purification is carried out to obtain a graphene quantum dot dry powder. Purification can take the following steps:
  • the reaction system is filtered, and the filtrate is a graphene quantum dot solution
  • the mixed crystal of the graphene quantum dot and the salt is washed with an organic solvent, washed, and the organic phase-insoluble inorganic salt is removed by filtration, and finally the organic phase is evaporated to obtain a graphene quantum dot dry powder.
  • the organic solvent is preferably a relatively polar organic solvent such as methanol, ethanol, ethylene glycol, (0.5-10): 1 (v/v) 37% hydrochloric acid-methanol solution, tetrahydrofuran (THF), At least one of formic acid, acetic acid, acetonitrile, N,N-dimethylformamide (DMF), diethyl ether, and acetone. More preferably, the organic solvent is at least one of methanol, acetonitrile, tetrahydrofuran, 1:1 (v/v) 37% hydrochloric acid-methanol solution.
  • a relatively polar organic solvent such as methanol, ethanol, ethylene glycol, (0.5-10): 1 (v/v) 37% hydrochloric acid-methanol solution, tetrahydrofuran (THF), At least one of formic acid, acetic acid, acetonitrile, N,N-dimethylformamide (DMF), diethyl ether
  • the oxygen content of the graphene quantum dot can also be reduced by purifying after purifying: the purified product is reacted with a reducing agent in an organic solvent, and purified. A graphene quantum dot dry powder is obtained.
  • the above purified product is also a graphene quantum dot dry powder, its oxygen content is relatively high, and after a single reduction step, a graphene quantum dot having a relatively low oxygen content can be obtained.
  • One skilled in the art can select whether to perform this step based on the demand for the performance of the target product.
  • the reducing agent may be at least one of sodium borohydride, potassium borohydride, hydrazine hydrate, zinc-hydrochloric acid, iron-acetic acid, lithium aluminum hydride, sodium naphthalene, sodium amalgam, and Raney nickel.
  • the reducing agent is at least one of sodium borohydride, zinc-hydrochloric acid (1:2, molar ratio), and sodium amalgam.
  • the amount of the reducing agent to be added may be 2 to 2.5 equivalents (the chemical formula of the case where the GQDs have the highest oxygen content is C 2 (OH) 2 , thereby calculating the reducing agent equivalent).
  • the reaction medium for the reduction reaction may be water or a tetrahydrofuran solution.
  • the step may specifically be: preparing the graphene quantum dot dry powder obtained after purification into a water or tetrahydrofuran solution having a mass percentage of 0.1 to 5%, and heating in an air bath, and the heating temperature may be 25 ° C to 100 ° C, preferably 30 °C ⁇ 60°C, and the reducing agent added is reduced and refluxed for 0.5 ⁇ 4h to obtain graphene quantum dots with low oxygen content, and then purified, and the graphene quantum dot dry powder with lower oxygen content can be obtained.
  • the specific purification can be:
  • the reaction system after the reduction reaction is filtered, and the filtrate is evaporated to obtain a mixed crystal of a low oxygen content graphene quantum dot and a salt; the crystal is washed with an organic solvent, and the inorganic salt insoluble in the organic phase is removed by filtration to obtain a low oxygen content.
  • the organic solvent is preferably a less polar organic solvent such as cyclohexane, n-hexane, petroleum ether (30-60), petroleum ether (60-90), petroleum ether (90-120), ethyl acetate, dimethyl carbonate, dichloromethane, chloroform, tetrachlorination Carbon or the like is preferably ethyl acetate, petroleum ether (60-90), n-hexane, dichloromethane or a mixture thereof.
  • the organic solvent is preferably a less polar organic solvent such as cyclohexane, n-hexane, petroleum ether (30-60), petroleum ether (60-90), petroleum ether (90-120), ethyl acetate, dimethyl carbonate, dichloromethane, chloroform, tetrachlorination Carbon or the like is preferably ethyl acetate, petroleum ether (60-90), n-hexane, dichloromethane or
  • Step 3 is a process for obtaining graphene quantum dots of different oxygen contents, and the present invention is achieved by using a gradient elution method. Specifically, extraction of graphene quantum dots of different oxygen contents is achieved by using eluents of different polarities.
  • the graphene quantum dots eluted by the highly polar eluent have a higher oxygen content and a lower polarity and a lower oxygen content.
  • the supported carrier may be alumina, chromatographic silica gel or activated carbon, specifically, alumina of 60 mesh to 325 mesh, activated carbon of 60 mesh to 325 mesh, or silica gel of 60 to 325 mesh.
  • the carrier is a chromatography silica gel, more preferably 100 to 200 mesh chromatography silica gel.
  • the steps of the load can be specifically as follows:
  • the graphene quantum dot dry powder is formed into a paste with a carrier in a solvent, and dried to obtain a carrier supporting the graphene quantum dots. More specifically, the graphene quantum dot dry powder is dissolved in a solvent to prepare a solution having a mass percentage of 0.5 to 5%, and then an equal volume of the carrier is added to the solution, and the mixture is slowly stirred to form a paste, and the obtained paste is Drying at room temperature gives a support carrying graphene quantum dots.
  • the solvent may be at least one of an organic solvent such as methanol, ethanol, tetrahydrofuran, ethyl acetate, acetone, cyclohexane or dichloromethane, preferably methanol, tetrahydrofuran, dichloromethane or a mixture thereof.
  • an organic solvent such as methanol, ethanol, tetrahydrofuran, ethyl acetate, acetone, cyclohexane or dichloromethane, preferably methanol, tetrahydrofuran, dichloromethane or a mixture thereof.
  • the eluent used in the gradient elution includes a first polar solvent and a second polar solvent, and the polarity of the first polar solvent is greater than the polarity of the second polar solvent, that is, the first polar solvent is More polar solvents, which may specifically include: water, methanol, ethanol, ethylene glycol, hydrochloric acid-methanol solution, tetrahydrofuran, formic acid, acetic acid, acetonitrile, N,N-dimethylformamide, diethyl ether, acetone, nitrate One or more of the base methane; the second polar solvent is a less polar solvent comprising: cyclohexane, n-hexane, petroleum ether, ethyl acetate, dimethyl carbonate, dichloromethane, three Methyl chloride, carbon tetrachloride One or more of them.
  • the change in the polarity of the eluent can be achieved by varying the ratio of the first polar solvent to the second polar solvent.
  • the volume ratio of the second polar solvent to the first polar solvent may be 1: (0.05 to 20).
  • Gradient elution is specifically: gradient elution by vacuum liquid chromatography or column chromatography.
  • vacuum liquid chromatography is used for gradient elution, that is, the carrier supporting the graphene quantum dots is separated and purified by vacuum liquid chromatography (VLC), and the oxygen content is obtained.
  • VLC vacuum liquid chromatography
  • a short silica gel column was filled, and the carrier loaded with GQDs in the previous step was added to the top of the column for VLC vacuum liquid chromatography.
  • the eluent is selected from a small polar solvent with a mixing ratio of 1: (0.05 to 20) and a large polar solvent, and successively eluted in batches. After the elution, graphene quantum dots with different oxygen contents can be obtained. Subsequently, the eluted products can be separately characterized by fluorescence to determine the purity thereof, and the organic phase of the single component is evaporated to obtain graphene quantum dots having different oxygen contents.
  • the graphene quantum dots were purified by vacuum liquid chromatography. The amount of eluent was small, and the isolated graphene quantum dots had a narrower oxygen content distribution.
  • the invention provides a method for preparing graphene quantum dots with different oxygen content, which firstly disperses graphene oxide in a solution of peroxide to obtain a graphene oxide dispersion; in this step, the peroxide acts as an oxidant. It can be beneficial to form graphene quantum dots with wide oxygen content distribution, which provides a precondition for subsequent obtaining of different oxygen content graphene quantum dots; then, the graphene oxide dispersion liquid is mixed with the alkali liquid to obtain graphene quantum dots. Finally, the graphene quantum dots are loaded and then eluted with a gradient. By changing the polarity of the eluent, the graphene quantum dots with different oxygen contents are obtained after elution.
  • the oxygen content of the graphene quantum dots can be controlled, thereby achieving controllable emission wavelength of the product, and providing reliable use for graphene quantum dots in the fields of LED, cell labeling and the like. Premise.
  • the method provided by the present invention is also simple and easy to operate.
  • Embodiments of the present invention also provide a graphene quantum dot having an oxygen content of 2% to 40%.
  • the emission wavelength may be 500 nm to 750 nm; the oxygen content is preferably 15% to 40%; the emission wavelength is preferably 550 nm to 700 nm; the oxygen content is more preferably 15% to 25%; and the emission wavelength is more preferably 550 nm to 600 nm.
  • the graphene quantum dots can be applied to a fluorescent material.
  • another embodiment of the present invention also provides a fluorescent material.
  • the fluorescent material includes the above-described graphene quantum dots.
  • the fluorescent material may be a fluorescent dye used for cell labeling, a fluorescent powder of an LED, a light emitting layer material of a WLED, or the like.
  • the graphene oxide concentration was 0.3% by weight.
  • the saturated sodium hydroxide solution was heated in a water bath at 20 ° C until the temperature of the system was the same as the temperature of the water bath, and mechanical stirring or magnetic stirring was started at a rotation speed of 100 rpm.
  • the graphene oxide dispersion was dropped into a saturated sodium hydroxide solution dropwise, and the reaction was sufficiently carried out by stirring.
  • the volume ratio of the graphene oxide dispersion to the saturated sodium hydroxide solution was 10:1.
  • the mixture was filtered, and the cake was discarded to obtain an aqueous solution of graphene quantum dots (GQDs).
  • GQDs graphene quantum dots
  • the aqueous solution of GQDs was added to hydrochloric acid to adjust the pH to 6-7, and then slowly evaporated to dryness to obtain a mixed crystal of GQDs and a salt.
  • the crystals were washed with a 37% hydrochloric acid-methanol solution having a volume ratio of 5:1, and the inorganic salts insoluble in the system were removed by filtration, and the solvent was evaporated to dryness to obtain a dry powder of GQDs.
  • the present embodiment produces graphene quantum dots having different oxygen contents.
  • Fig. 2 The above sample 1 was subjected to fluorescence test analysis, and the analysis results are shown in Fig. 2. It can be seen from Fig. 2 that the prepared graphene quantum dots have excitation dependence, and light of different wavelengths excites them, and the peak positions of the emission peaks are different, and have unique fluorescence characteristics.
  • the concentration of GO was 4.5% by weight.
  • the saturated potassium hydroxide solution was heated in an oil bath at 120 ° C until the temperature of the system was the same as the temperature of the water bath, and mechanical stirring or magnetic stirring was started at a rotation speed of 500 rpm.
  • the graphene oxide dispersion was dropped into a saturated potassium hydroxide solution dropwise by dropwise addition, and the reaction was sufficiently carried out by stirring. Oxidation The volume ratio of the graphene dispersion to the saturated potassium hydroxide solution was 100:1. After all the dropwise addition was completed, the mixture was filtered, and the cake was discarded to obtain an aqueous solution of GQDs.
  • the aqueous solution of GQDs was added to hydrochloric acid to adjust the pH to 6-7, and then slowly evaporated to dryness to obtain a mixed crystal of GQDs and a salt.
  • the crystals were washed with tetrahydrofuran, the inorganic salts insoluble in THF were removed by filtration, and finally THF was evaporated to give a dry powder of GQDs.
  • the dry powder of the previous GQDs was made into a 1% aqueous solution, heated in an air bath, heated at 95 ° C, and 2.5 equivalents of hydrazine hydrate were added to reduce GQDs, and refluxed for 2 hours. After completion of the reaction, the possible residue was removed by filtration, and excess reducing agent was quenched with hydrochloric acid. The filtrate was again evaporated to give a mixed crystal of a low oxygen content of GQDs and a salt. The crystals were washed with ethyl acetate, and the inorganic salts insoluble in ethyl acetate were removed by filtration, and evaporated to dryness to give a dry powder of low oxygen content GQDs.
  • the dry powder and the 0.5% methanol solution were added to an equal volume of 200 mesh chromatography silica gel, and the mixture was slowly stirred to form a paste, and the obtained paste was dried at room temperature to obtain a carrier supporting GQDs. .
  • a short silica gel column was filled, and the silica gel loaded with GQDs was added to the top of the column in the previous step, and subjected to VLC vacuum liquid chromatography.
  • the eluent was selected from dichloromethane-ethanol in a mixing ratio of 1:0.05 to 1:10, and gradually divided into 10 groups and gradually increased from 1:0.05 to 1:1, and successively eluted in batches. Among them, 1:0.155, 1:0.575, 1:1 components belong to the pure phase. After the three pure phases were separately evaporated to dryness, graphene quantum dot dry powders having different oxygen contents were obtained, which were respectively recorded as sample 3, sample 4, and sample 5.
  • Figure 3 is an atomic force microscope image of Sample 3. As can be seen from the figure, the prepared product is a graphene quantum dot.
  • the present embodiment produces graphene quantum dots having different oxygen contents.
  • the concentration of GO was 2% by weight.
  • the saturated sodium hydroxide solution was heated in a water bath at 80 ° C until the temperature of the system was the same as the temperature of the water bath, and mechanical stirring or magnetic stirring was started at a rotation speed of 500 rpm.
  • the graphene oxide dispersion was dropped into a saturated sodium hydroxide solution dropwise by dropwise addition, and the reaction was sufficiently carried out by stirring.
  • the volume ratio of the graphene oxide dispersion to the saturated sodium hydroxide solution was 50:1. After all the dropwise addition was completed, the mixture was filtered, and the cake was discarded to obtain an aqueous solution of GQDs.
  • the aqueous solution of GQDs was added to hydrochloric acid to adjust the pH to 6-7, and then slowly evaporated to dryness to obtain a mixed crystal of GQDs and a salt.
  • the crystals were washed with tetrahydrofuran, the inorganic salts insoluble in THF were removed by filtration, and finally THF was evaporated to give a dry powder of GQDs.
  • the dry powder fraction of the previous GQDs was mixed into a 2% aqueous solution, heated in an air bath at a heating temperature of 30 ° C, and GQDs were reduced by adding 2 equivalents of hydrazine hydrate, and refluxed for 2 hours. After completion of the reaction, the possible residue was removed by filtration, and excess reducing agent was quenched with hydrochloric acid. The filtrate was again evaporated to give a mixed crystal of a low oxygen content of GQDs and a salt. The crystals were washed with ethyl acetate, and the inorganic salts insoluble in ethyl acetate were removed by filtration, and evaporated to dryness to give a dry powder of low oxygen content GQDs.
  • the dry powder of the low oxygen content GQDs and the dry powder with higher oxygen content obtained above are mixed 1:1 together, and a 3 wt% methanol solution is prepared together, and an equal volume of 200 mesh chromatography silica gel is added to the solution, and the mixture is slowly stirred. A paste was formed, and the obtained paste was dried at room temperature to obtain a GQDs-loaded carrier.
  • a short silica gel column was filled, and the silica gel loaded with GQDs was added to the top of the column in the previous step, and subjected to VLC vacuum liquid chromatography.
  • the eluent was selected from petroleum ether (boiling range 60-90)-acetone with a mixing ratio of 1:0.05 to 1:20, and gradually divided into 20 groups and gradually increased from 1:0.05 to 1:20, and successively eluted in batches.
  • the components of 1:1, 1:15, 1:20 belong to the pure phase, and the three pure phases are separately evaporated to obtain the dry powder of graphene quantum dots with different oxygen contents, which are respectively recorded as sample 6, sample 7 And sample 8.
  • Figure 4 is an atomic force microscope image of Sample 6. As can be seen from the figure, the prepared product is a graphene quantum dot.
  • the concentration of GO was 4% by weight.
  • a saturated ethylenediamine solution is provided.
  • the saturated ethylenediamine solution was heated in a water bath at 80 ° C until the temperature of the system was the same as the temperature of the water bath, and mechanical stirring or magnetic stirring was started at a rotation speed of 500 rpm.
  • the graphene oxide dispersion was dropped into a saturated ethylenediamine solution dropwise by dropwise addition, and the reaction was sufficiently carried out by stirring.
  • the volume ratio of the graphene oxide dispersion to the saturated ethylenediamine solution was 80:1. After all the dropwise addition was completed, the mixture was filtered, and the cake was discarded to obtain an aqueous solution of GQDs.
  • the aqueous solution of GQDs was added to hydrochloric acid to adjust the pH to 6-7, and then slowly evaporated to dryness to obtain a mixed crystal of GQDs and a salt.
  • the crystals were washed with tetrahydrofuran, the inorganic salts insoluble in THF were removed by filtration, and finally THF was evaporated to give a dry powder of GQDs.
  • the GQDs dry powder was mixed into a 3% methanol solution, and an equal volume of 200 mesh chromatography silica gel was added to the solution to slowly form a paste, and the obtained paste was dried at room temperature to obtain a GQDs-loaded carrier.
  • a short silica gel column was filled, and the silica gel loaded with GQDs was added to the top of the column in the previous step, and subjected to VLC vacuum liquid chromatography.
  • the eluent was selected from ethyl acetate-methanol in a mixing ratio of 1:0.05 to 1:20, and gradually divided into 20 groups and gradually increased from 1:0.05 to 1:20, and successively eluted in batches.
  • the 1:6, 1:13 and 1:18 components belong to the pure phase, and the three pure phases are separately evaporated to obtain the graphene quantum dot dry powders with different oxygen contents, which are respectively recorded as sample 9, sample 10 And sample 11.
  • Figure 4 is an atomic force microscope image of Sample 10. As can be seen from the figure, the prepared product is a graphene quantum dot.
  • the fluorescence emission wavelength is also different.
  • the method provided by the invention can prepare graphene quantum dots with an emission wavelength of 500 nm to 750 nm, and in particular, can produce graphene quantum dots with an emission wavelength of 550 nm to 700 nm.

Abstract

提供一种不同含氧量的石墨烯量子点的制备方法、石墨烯量子点和荧光材料。该制备方法包括如下步骤：将氧化石墨烯分散在过氧化物溶液中，得氧化石墨烯分散液；将氧化石墨烯分散液与碱液混合，提纯，得到石墨烯量子点干粉；将石墨烯量子点干粉负载于载体后，进行梯度洗脱，得到不同含氧量的石墨烯量子点。该制备方法可以实现石墨烯量子点的含氧量可控，进而实现产品发射波长可控，为石墨烯量子点在LED、细胞标记等领域的应用提供了可靠的前提。该方法还具有简单、易于操作的特点。

Description

不同含氧量的石墨烯量子点的制备方法、石墨烯量子点和荧光材料
本申请要求于2015年08月25日提交中国专利局，申请号为201510528994.9、发明名称为“不同含氧量的石墨烯量子点的制备方法、石墨烯量子点和荧光材料”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明属于荧光纳米材料技术领域，具体涉及一种不同含氧量的石墨烯量子点的制备方法、石墨烯量子点和荧光材料。
背景技术
自从2004年英国曼彻斯特大学的Andre Geim及Konstantin Novoselof首次成功剥离热解石墨并观测到石墨烯以来，学界内对于新型碳材料的研究热度就一直没有消退过。石墨烯的成功分离意味着理论对于二维晶体热力学不稳定的预言被破除，也就带来了许多新领域研究的可能。
完美的石墨烯具有理想的二维结构，它由六边形晶格组成，每个碳原子通过σ键在晶格平面方向上与其他的三个碳原子结合，未成σ键的电子则作为π电子，组成了垂直于晶格平面的π轨道体系。π电子可在平面上任意移动。但更为重要的是，由于石墨烯特有的结构，其能带结构呈狄拉克锥的形式，而在狄拉克点上，石墨烯的导带和价带重合，因此在其狄拉克点上电子和空穴的有效质量皆为零，对应的电子和空穴的迁移率都相同且无限接近于无穷大，这意味着其载子既可以是空穴也可以是电子，且其载子迁移率极大，因此理想的石墨烯应当具有极好的导电性，预测其能够承受比铜高六个数量级的电流密度。
目前的研究对于大片层的石墨烯已经有一系列激动人心的研究工作已经发表，而对于二维的片层尺度大小被束缚在玻尔半径的石墨烯及氧化石墨烯颗粒的研究，也正如火如荼的进行着。对于这样的石墨烯颗粒，由于保留了一定的氧化官能团或缺陷，且尺寸变小，故其能带并非连续，由此导致其载子可被激发。载子被激发后形成激子，而激子又被限制在了该石墨烯的三个空间方向的能带隙里，单层石墨烯厚度在1nm左右，片层大小在玻尔半径左右，由于这样的石墨烯对应的能带隙较大，这导致激子退激发后形成的激光发射波长较宽，具有极好的激光特性。而这类石墨烯颗粒，有类似无机材料中的半导体量子点所具有的特性，因此被称之为石墨烯量子点，石墨烯量子点的半径在波尔半径之内，其无毒无害，荧光波长窄，激光波长宽，在发光二级管(LED)和生物成像以及光伏器件和传感器上能起到极好的应用。
目前对于石墨烯量子点的研究中，主要采用的制备方法有四种。这四种方法分别是对石墨烯进行再氧化的二次氧化法、从有机小分子出发的有机合成法、电子束或离子束蚀刻的方法以及对碳材料进行微观切割的方法。然而，现有制备方法不能够制备可控的含氧量的石墨烯量子点，这造成了产品也就是石墨烯量子点的发射波长不可调，换句话说，不能够选择合适的发光颜色，在LED等的应用中就难以构成合适的色坐标。另外，含氧量过低的石墨烯量子点往往是油溶性的，难以在生物中应用，然而处理成一定含氧量的石墨烯量子点，就能够使其在水相中有较高的溶解度，从而便于进行细胞标记等生物应用。
发明内容
本发明所要解决的技术问题在于克服现有技术的缺陷，提供一种不同含氧量的石墨烯量子点的制备方法。
本发明提供一种不同含氧量的石墨烯量子点的制备方法，其包括如下步骤：
步骤一：将氧化石墨烯分散在过氧化物溶液中，得氧化石墨烯分散液；
步骤二：将所述氧化石墨烯分散液与碱液混合，提纯，得到石墨烯量子点干粉；
步骤三：将所述石墨烯量子点干粉负载于载体后，进行梯度洗脱，得到不同含氧量的石墨烯量子点。
其中，所述的氧化石墨烯的碳氧比为0.5～5。所述氧化石墨烯分散液中氧化石墨烯的质量浓度为0.1％～5％；和/或，所述过氧化物的溶液的质量浓度为3％～30％。所述过氧化物为过氧化氢、过硫酸铵、过硫酸钠、过硫酸氢钾、过硼酸钠、过氧二苯甲酰、过氧二月桂酰中的至少一种。
进一步，所述步骤二中，在所述提纯后还包括如下步骤：将提纯后的产物在溶剂中与还原剂进行反应，提纯，得到石墨烯量子点干粉。
具体地，步骤三中所述梯度洗脱具体为：采用真空液相色谱法或者柱层析法进行梯度洗脱。所述梯度洗脱使用的洗脱剂包括第一极性溶剂和第二极性溶剂，所述第一极性溶剂的极性大于所述第二极性溶剂的极性；所述第一极性溶剂包括：水、甲醇、乙醇、乙二醇、盐酸-甲醇溶液、四氢呋喃、甲酸、乙酸、乙腈、N，N-二甲基甲酰胺、乙醚、丙酮、硝基甲烷中的一种或多种；所述第二极性溶剂包括:环己烷、正己烷、石油醚、乙酸乙酯、碳酸二甲酯、二氯甲烷、三氯甲烷、四氯化碳中的一种或多种。
以及，本发明提供一种石墨烯量子点，其含氧量为2％～40％。
进一步，其发射波长为550nm～750nm。
进一步，本发明提供一种荧光材料，其包括上述不同含氧量的石墨烯量子点的制备方法制备的石墨烯量子点。
本发明提供一种不同含氧量石墨烯量子点的制备方法，该方法是首先将氧化石墨烯分散在过氧化物的溶液中，得到氧化石墨烯分散液；此步骤中过氧化物作为氧化剂，其可以有利于形成含氧量分布较宽的石墨烯量子点，为后续得到不同含氧量的石墨烯量子点提供了前提；然后将氧化石墨烯分散液与碱液混合，得到石墨烯量子点；最后将石墨烯量子点负载后梯度洗脱，通过改变洗脱剂的极性，洗脱后得到不同含氧量的石墨烯量子点。由此可知，通过采用本发明提供的方法，可以实现石墨烯量子点的含氧量可控，进而实现产品发射波长可控，为石墨烯量子点在LED、细胞标记等领域的应用提供了可靠的前提。此外，本发明提供的方法还具有简单、易于操作的特点。
附图说明
图1是本发明实施例1中样品1的原子力显微镜图；
图2是本发明实施例1中样品1在不同激发波长下的荧光光谱图；
图3是本发明实施例2中样品3的原子力显微镜图；
图4是本发明实施例3中样品6的原子力显微镜图；
图5是本发明实施例4中样品10的原子力显微镜图；
图6是本发明实施例中样品1至样品5，以及样品9至样品11的归一化荧光光谱图。
具体实施方式
为了使本发明的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本发明进行进一步详细说明。应当理解，此处所描述的具体实施例仅仅用以解释本发明，并不用于限定本发明。
本发明实施例提供一种不同含氧量的石墨烯量子点的制备方法，其包括如下步骤：
步骤一：将氧化石墨烯分散在过氧化物溶液中，得氧化石墨烯分散液；
步骤二：将所述氧化石墨烯分散液与碱液混合，提纯，得到石墨烯量子点干粉；
步骤三：将所述石墨烯量子点干粉负载后，进行梯度洗脱，得到不同含氧量的石墨烯量子点。
步骤一是制备氧化石墨烯分散液的过程。其中，为了避免氧化石墨烯发生团聚等情况，分散优选采用超声分散，进一步地，超声分散的时间可以为0.5h～2h。过氧化物用于在溶液中形成羟基自由基，起到氧化剂的作用。本发明人发现，采用过氧化物作为氧化剂，有利于形成含氧量分布较宽的石墨烯量子点，为得到不同含氧量的石墨烯量子点提供了前提。该过氧化物可以为有机过氧化物，也可以为无机过氧化物，例如可以为过氧化氢、过硫酸铵、过硫酸钠、过硫酸氢钾、过硼酸钠、过氧二苯甲酰、过氧二月桂酰等过氧化物中的至少一种。优选地，所述过氧化物为过氧化氢、过硫酸铵、或者过氧化二苯甲酰中的至少一种。
其中，制备的氧化石墨烯分散液中氧化石墨烯的质量浓度优选为0.1～5％，氧化石墨烯浓度过高，体系会比较绵绸，影响石墨烯量子点的产率；氧化石墨烯浓度过低则给收集产物带来难度。过氧化物溶液的质量浓度优选为3～30％。过氧化物浓度过低，石墨烯量子点产率较低；过氧化物 浓度过高，容易造成反应体系不稳定，放热过大。
本发明人还发现，氧化石墨烯GO的碳氧比例对最终石墨烯量子点的含氧量具有一定的影响，原料的碳氧比例越大，石墨烯量子点的含氧量分布越宽。所述的氧化石墨烯的碳氧比(C：O)可以为0.5～5，优选地，所述氧化石墨烯的碳氧比为1～2。
步骤二是制备氧化石墨烯量子点的过程。所述碱液可以为无机碱液，如NaOH，KOH，也可以为有机碱液，如乙二胺、三甲胺，正丁胺，四甲基氢氧化铵等。碱液优选为饱和溶液。步骤二可以是：将所述氧化石墨烯分散液缓慢加入到饱和碱液中。进一步地，为了控制反应速度，提高原料混合的均匀性，上述混合优选采用滴加混合，并且在滴加前及滴加过程中使碱液处于搅拌状态。具体地可以为：采用滴加的方式将氧化石墨烯分散液滴到搅拌的碱液中。上述搅拌可以为机械搅拌或磁力搅拌，转速可以为60rpm～800rpm。氧化石墨烯分散液与饱和碱液的混合反应的温度可以为0～120℃，反应温度对于制备的石墨烯量子点的尺寸具有一定的影响，温度越高，尺寸越小。但是温度越高，反应也越剧烈，越不容易控制。优选地，反应温度为20℃～30℃。加热方式优选采用水浴加热或油浴加热。
优选地，所述氧化石墨烯分散液与饱和碱液的体积比为(10～100)：1。反应结束后进行提纯可得到石墨烯量子点干粉。提纯可以采用如下步骤：
将反应后体系过滤，滤液即为石墨烯量子点溶液；
调整石墨烯量子点溶液的pH到6～7，可以选用盐酸或者其他酸来调节。调整pH值后缓慢蒸干，得到石墨烯量子点与盐的混合结晶物；
将所述石墨烯量子点与盐的混合结晶物用有机溶剂洗涤，洗涤后过滤除去有机相不溶的无机盐，最后蒸干有机相，得到石墨烯量子点干粉。
其中，所述有机溶剂优选为极性较大的有机溶剂，例如甲醇、乙醇、乙二醇、(0.5～10):1(v/v)的37％盐酸-甲醇溶液、四氢呋喃(THF)、 甲酸、乙酸、乙腈、N，N-二甲基甲酰胺(DMF)、乙醚、丙酮中的至少一种。更优选地，有机溶剂为甲醇、乙腈、四氢呋喃、1:1(v/v)的37％盐酸-甲醇溶液中的至少一种。
当需要含氧量较低的氧化石墨烯量子点时，还可以在提纯后通过如下步骤降低石墨烯量子点的含氧量：将提纯后的产物在有机溶剂中与还原剂进行反应，提纯，得到石墨烯量子点干粉。上述提纯后的产物虽然也是石墨烯量子点干粉，但是其含氧量相对较高，再经过一次还原的步骤，可以获得含氧量相对较低的石墨烯量子点。本领域技术人员可以根据对目标产物性能的需求来选择是否进行此步骤。
上述还原剂可以为硼氢化钠、硼氢化钾、水合肼、锌-盐酸、铁-乙酸、氢化铝锂、萘基钠、钠汞齐、雷尼镍中的至少一种。优选地，所述还原剂为硼氢化钠，锌-盐酸(1:2，摩尔比)，钠汞齐中的至少一种。还原剂的加入量可以为2～2.5个当量(计GQDs含氧量最高情况下可能的化学式为C2(OH)2，以此计算还原剂当量)。
还原反应的反应介质，即上述溶剂可以为水或四氢呋喃溶液。此步骤具体可以为：将提纯后得到的石墨烯量子点干粉配成质量百分比为0.1～5％的水或四氢呋喃溶液，在空气浴下加热，加热温度可以为25℃～100℃，优选为30℃～60℃，并加入的还原剂还原回流0.5～4h，得到含氧量较低的石墨烯量子点，而后再进行提纯，可以得到含氧量较低的石墨烯量子点干粉。提纯具体可以为：
将还原反应后的反应体系过滤，蒸干滤液，得到低含氧量的石墨烯量子点和盐的混合结晶；再用有机溶剂洗涤结晶，过滤除去有机相中不溶的无机盐，得到低含氧量石墨烯量子点的干粉；其中，所述有机溶剂优选为极性较小的有机溶剂，如环己烷、正己烷、石油醚(30-60)、石油醚(60-90)、石油醚(90-120)、乙酸乙酯、碳酸二甲酯、二氯甲烷、三氯甲烷、四氯化 碳等，优选为乙酸乙酯，石油醚(60-90)，正己烷，二氯甲烷或它们的混合物。
步骤三是得到不同含氧量的石墨烯量子点的过程，本发明通过采用梯度洗脱法来实现。具体而言，通过采用不同极性的洗脱液来实现不同含氧量的石墨烯量子点的提取。极性大的洗脱液洗脱出的石墨烯量子点的含氧量较高，极性小的含氧量较低。
本步骤具体是先进行性负载，再进行梯度洗脱。先进性负载有助于减少洗脱剂的用量，使操作更加简便。负载的载体可以为氧化铝、层析硅胶或活性炭，具体可以为60目～325目的氧化铝，60目～325目的活性炭，或60～325目层析硅胶。优选地，载体为的层析硅胶，更优选为100～200目的层析硅胶。
负载的步骤具体可以如下：
将石墨烯量子点干粉在溶剂中与载体形成糊状物，干燥后得负载石墨烯量子点的载体。更具体地，将石墨烯量子点干粉溶解于溶剂中，配成质量百分比为0.5～5％的溶液，再加入与溶液等体积的载体，缓慢搅拌形成糊状物，将得到的糊状物在室温下烘干，得到负载石墨烯量子点的载体。其中，所述的溶剂可以为甲醇、乙醇、四氢呋喃、乙酸乙酯、丙酮、环己烷、二氯甲烷等有机溶剂中的至少一种，优选为甲醇，四氢呋喃，二氯甲烷或它们的混合物。
梯度洗脱使用的洗脱剂包括第一极性溶剂和第二极性溶剂，所述第一极性溶剂的极性大于所述第二极性溶剂的极性，即第一极性溶剂为极性较大的溶剂，其具体可以包括：水、甲醇、乙醇、乙二醇、盐酸-甲醇溶液、四氢呋喃、甲酸、乙酸、乙腈、N，N-二甲基甲酰胺、乙醚、丙酮、硝基甲烷中的一种或多种；第二极性溶剂为极性较小的溶剂，其包括:环己烷、正己烷、石油醚、乙酸乙酯、碳酸二甲酯、二氯甲烷、三氯甲烷、四氯化碳 中的一种或多种。通过改变第一极性溶剂和第二极性溶剂的比例，可实现洗脱剂极性的变化。梯度洗脱过程中，第二极性溶剂与第一极性溶剂的体积比可以为1：(0.05～20)。
梯度洗脱具体为：采用真空液相色谱法或者柱层析法进行梯度洗脱。作为本发明的优选方案，选用真空液相色谱法进行梯度洗脱，即将负载石墨烯量子点的载体利用真空液相色谱法(VLC)对其进行分离纯化，得到就得到了含氧量不同的石墨烯量子点。更具体地，该步骤如下：
填充一支短硅胶柱，将上一步得到负载了GQDs的载体加在柱顶，进行VLC真空液相色谱法分离。洗脱剂选用混合比为1:(0.05～20)的小极性溶剂与大极性溶剂，逐次分批洗脱。洗脱后便可得到不同含氧量的石墨烯量子点。后续可以对洗脱产物分别进行荧光表征确定其纯度，将单一组分的有机相蒸干，就得到了含氧量不同的石墨烯量子点。
选用真空液相色谱法纯化石墨烯量子点，洗脱剂用量少，分离出的石墨烯量子点含氧量分布更窄。
本发明提供一种不同含氧量石墨烯量子点的制备方法，该方法是首先将氧化石墨烯分散在过氧化物的溶液中，得到氧化石墨烯分散液；此步骤中过氧化物作为氧化剂，其可以有利于形成含氧量分布较宽的石墨烯量子点，为后续得到不同含氧量的石墨烯量子点提供了前提；然后将氧化石墨烯分散液与碱液混合，得到石墨烯量子点；最后将石墨烯量子点负载后梯度洗脱，通过改变洗脱剂的极性，洗脱后得到不同含氧量的石墨烯量子点。由此可知，通过采用本发明提供的方法，可以实现石墨烯量子点的含氧量可控，进而实现产品发射波长可控，为石墨烯量子点在LED、细胞标记等领域的应用提供了可靠的前提。此外，本发明提供的方法还具有简单、易于操作的特点。
本发明实施例还提供一种石墨烯量子点，其含氧量为2％～40％，其发 射波长可以为500nm～750nm；含氧量优选为15％～40％；发射波长优选为550nm～700nm；含氧量更优选为15％～25％；发射波长更优选为550nm～600nm。该石墨烯量子点可以应用于荧光材料上。
相应的，本发明另一实施例还提供一种荧光材料。该荧光材料包括上述石墨烯量子点。具体而言，该荧光材料可以为用于细胞标记的荧光染料，也可以为LED的荧光粉，还可以为WLED的发光层材料，等等。
以下结合具体实施例对本发明的具体实现进行详细描述。
实施例1：
将氧化石墨烯(C:O＝5)溶解于浓度为5wt％的过氧化氢溶液中，在180W功率下超声分散30min，配成氧化石墨烯分散液。该分散液中，氧化石墨烯浓度为0.3wt％。
配置饱和氢氧化钠溶液。
将饱和氢氧化钠溶液在20℃的水浴下加热，至体系温度与水浴温度相同，开始机械搅拌或磁力搅拌，转速为100rpm。接着，氧化石墨烯分散液以逐滴加入的方式滴入饱和氢氧化钠溶液中，通过搅拌充分反应。氧化石墨烯分散液与饱和氢氧化钠溶液的体积比例为10：1。全部滴加完成后，将混合液过滤，弃去滤饼，得到石墨烯量子点(GQDs)的水溶液。
将GQDs的水溶液加入盐酸调整pH到6-7，再缓慢蒸干，得到GQDs与盐的混合结晶。再用体积比为5:1的37％盐酸-甲醇溶液洗涤结晶，过滤除去体系中不溶的无机盐，蒸干去除溶剂，得到GQDs的干粉。
将GQDs干粉溶于甲醇，配成质量浓度为5％的甲醇溶液，加入与溶液等体积的200目层析硅胶，缓慢搅拌形成糊状物，再将得到的糊状物在室 温下烘干，得到了负载GQDs的载体。
填充一支短硅胶柱，将上一步得到负载了GQDs的硅胶加在柱顶，进行VLC真空液相色谱法分离。洗脱剂选用混合比为1:0.05到1:10的乙酸乙酯-甲醇，分成10组逐渐从1：0.05增到1：1，逐次分批洗脱。其中，1：3，1：10的组分属于纯相。两个纯相分别蒸干后，得到了含氧量不同的石墨烯量子点干粉，分别记为样品1和样品2。图1是样品1的原子力显微镜图，从图上可以看出，制备出的产品为石墨烯量子点，且其尺寸大致分布均匀。对上述样品进行元素分析，结果如下：
  [N]％ [C]％ [H]％ [S]％ [O]％
样品1 0 74.874 2.384 0.006 22.736
样品2 0 68.85 3.005 0.006 28.139
由此可知，本实施例制备出含氧量不同的石墨烯量子点。
对上述样品1进行荧光测试分析，分析结果如图2所示。由图2可知，制备的石墨烯量子点具备受激依赖性，不同波长的光激发它，发射峰的峰位位置不同，具有独特的荧光特性。
实施例2：
将GO(C:O＝1)溶解于浓度为30wt％的过硫酸铵的溶液中，在120w功率下超声1h分散，配置成石墨烯分散液。该分散液中，GO的浓度为4.5wt％。
配置饱和氢氧化钾溶液。
将饱和氢氧化钾溶液在120℃的油浴下加热，至体系温度与水浴温度相同，开始机械搅拌或磁力搅拌，转速为500rpm。接着，氧化石墨烯分散液以逐滴加入的方式滴入饱和氢氧化钾溶液中，通过搅拌充分反应。氧化 石墨烯分散液与饱和氢氧化钾溶液的体积比为100：1。全部滴加完成后，将混合液过滤，弃去滤饼，得到GQDs的水溶液。
将GQDs的水溶液加入盐酸调整pH到6-7，再缓慢蒸干，得到GQDs与盐的混合结晶。再用四氢呋喃洗涤结晶，过滤除去THF中不溶的无机盐，最后蒸干THF，得到GQDs的干粉。
将前面的GQDs的干粉配成1％的水溶液，在空气浴下加热，加热温度为95℃，并加入2.5个当量的水合肼对GQDs进行还原，回流2h。完成反应后，过滤除去可能的残渣，用盐酸淬灭过量的还原剂。再蒸干滤液，得到低含氧量的GQDs和盐的混合结晶。再用乙酸乙酯洗涤结晶，过滤除去乙酸乙酯中不溶的无机盐，蒸干后得到低含氧量GQDs的干粉。
将该干粉与配成0.5％的甲醇溶液，加入与溶液等体积的200目层析硅胶，缓慢搅拌形成糊状物，再将得到的糊状物在室温下烘干，得到了负载GQDs的载体。
填充一支短硅胶柱，将上一步得到负载了GQDs的硅胶加在柱顶，进行VLC真空液相色谱法分离。洗脱剂选用混合比为1:0.05到1:10的二氯甲烷-乙醇，分成10组逐渐从1：0.05增到1：1，逐次分批洗脱。其中，1：0.155，1：0.575，1：1的组分属于纯相。三个纯相分别蒸干后，得到了含氧量不同的石墨烯量子点干粉，分别记为样品3、样品4和样品5。图3是样品3的原子力显微镜图，从图上可以看出，制备出的产品为石墨烯量子点。
对上述样品进行元素分析，分析结果如下表：
  [N]％ [C]％ [H]％ [S]％ [O]％
样品3 1.56 95.671 0.016 0 2.747
样品4 0.76 91.92 0.744 0 6.576
样品5 1.82 88.63 1.181 0 8.369
由此可知，本实施例制备出含氧量不同的石墨烯量子点。
实施例3：
将GO(C:O＝2)溶解于浓度为20wt％的过硫酸钾溶液中，在100w功率下超声2h分散，配置成氧化石墨烯分散液。该分散液中，GO的浓度为2wt％。
配置饱和氢氧化钠溶液。
将饱和氢氧化钠溶液在80℃的水浴下加热，至体系温度与水浴温度相同，开始机械搅拌或磁力搅拌，转速为500rpm。接着，取氧化石墨烯分散液以逐滴加入的方式滴入饱和氢氧化钠溶液中，通过搅拌充分反应。氧化石墨烯分散液与饱和氢氧化钠溶液的体积比例为50：1。全部滴加完成后，将混合液过滤，弃去滤饼，得到GQDs的水溶液。
将GQDs的水溶液加入盐酸调整pH到6-7，再缓慢蒸干，得到GQDs与盐的混合结晶。再用四氢呋喃洗涤结晶，过滤除去THF中不溶的无机盐，最后蒸干THF，得到GQDs的干粉。
将前面的GQDs的干粉取部分配成2％的水溶液，在空气浴下加热，加热温度为30℃，并加入2个当量的水合肼对GQDs进行还原，回流2h。完成反应后，过滤除去可能的残渣，用盐酸淬灭过量的还原剂。再蒸干滤液，得到低含氧量的GQDs和盐的混合结晶。再用乙酸乙酯洗涤结晶，过滤除去乙酸乙酯中不溶的无机盐，蒸干后得到低含氧量GQDs的干粉。
将前述低含氧量GQDs干粉的与前面得到的含氧量较高的干粉1:1混合在一起，共同配成3wt％的甲醇溶液，加入与溶液等体积的200目层析硅胶，缓慢搅拌形成糊状物，再将得到的糊状物在室温下烘干，得到了负载GQDs的载体。
填充一支短硅胶柱，将上一步得到负载了GQDs的硅胶加在柱顶，进行VLC真空液相色谱法分离。洗脱剂选用混合比为1:0.05到1:20的石油醚(沸程60-90)-丙酮，分成20组逐渐从1：0.05增到1：20，逐次分批洗脱。其中，1：1，1：15，1：20的组分属于纯相，三个纯相分别蒸干后，得到了含氧量不同的石墨烯量子点干粉，分别记为样品6、样品7和样品8。图4是样品6的原子力显微镜图，从图上可以看出，制备出的产品为石墨烯量子点。
对上述样品进行元素分析，分析结果如下表：
  [N]％ [C]％ [H]％ [S]％ [O]％
样品6 1.09 95.262 0.006 0 3.642
样品7 0.001 80.63 1.973 0.002 17.385
样品8 0 75.242 2.802 0.004 21.952
由此可知我们获得了不同含氧量的石墨烯量子点。
实施例4：
将GO(C:O＝4)溶解于浓度为3wt％的过氧二苯甲酰的溶液中，在100w功率下超声2h分散，配置成氧化石墨烯分散液。该分散液中，GO的浓度为4wt％。
配置饱和乙二胺溶液。
将饱和乙二胺溶液在80℃的水浴下加热，至体系温度与水浴温度相同，开始机械搅拌或磁力搅拌，转速为500rpm。接着，取氧化石墨烯分散液以逐滴加入的方式滴入饱和乙二胺溶液中，通过搅拌充分反应。氧化石墨烯分散液与饱和乙二胺溶液的体积比例为80:1。全部滴加完成后，将混合液过滤，弃去滤饼，得到GQDs的水溶液。
将GQDs的水溶液加入盐酸调整pH到6-7，再缓慢蒸干，得到GQDs与盐的混合结晶。再用四氢呋喃洗涤结晶，过滤除去THF中不溶的无机盐，最后蒸干THF，得到GQDs的干粉。
将GQDs干粉配成3％的甲醇溶液，加入与溶液等体积的200目层析硅胶，缓慢搅拌形成糊状物，再将得到的糊状物在室温下烘干，得到了负载GQDs的载体。
填充一支短硅胶柱，将上一步得到负载了GQDs的硅胶加在柱顶，进行VLC真空液相色谱法分离。洗脱剂选用混合比为1：0.05到1：20的乙酸乙酯-甲醇，分成20组逐渐从1：0.05增到1：20，逐次分批洗脱。其中，1：6，1：13和1：18的组分属于纯相，三个纯相分别蒸干后，得到了含氧量不同的石墨烯量子点干粉，分别记为样品9、样品10和样品11。图4是样品10的原子力显微镜图，从图上可以看出，制备出的产品为石墨烯量子点。
对上述样品进行元素分析，分析结果如下表：
  [N]％ [C]％ [H]％ [S]％ [O]％
样品9 0.228 69.351 0.064 0.003 30.354
样品10 0.005 63.872 1.811 0 34.312
样品11 0.034 59.096 2.135 0.004 38.731
由此可知我们获得了不同含氧量的石墨烯量子点。
对样品1至样品5，以及样品9至样品11进行荧光分析，分析结果如图6所示。上述样品的发射波长依次为557nm，577nm，497nm，511nm，532nm，607nm，643nm，677nm。
由图6可知，石墨烯量子点的含氧量不同时，荧光发射波长也不同。本发明提供的方法可制备发射波长为500nm～750nm的石墨烯量子点，尤其是可以制备出发射波长为550nm～700nm的石墨烯量子点。
以上所述仅为本发明的较佳实施例而已，并不用以限制本发明，凡在本发明的精神和原则之内所作的任何修改、等同替换和改进等，均应包含在本发明的保护范围之内。

Claims (10)

  1. 一种不同含氧量的石墨烯量子点的制备方法，其包括如下步骤：
    步骤一：将氧化石墨烯分散在过氧化物溶液中，得氧化石墨烯分散液；
    步骤二：将所述氧化石墨烯分散液与碱液混合，提纯，得到石墨烯量子点干粉；
    步骤三：将所述石墨烯量子点干粉负载于载体后，进行梯度洗脱，得到不同含氧量的石墨烯量子点。
  2. 根据权利要求1所述的不同含氧量的石墨烯量子点的制备方法，其特征在于，所述的氧化石墨烯的碳氧比为0.5～5。
  3. 根据权利要求1所述的不同含氧量的石墨烯量子点的制备方法，其特征在于，所述氧化石墨烯分散液中氧化石墨烯的质量浓度为0.1％～5％；和/或，所述过氧化物的溶液的质量浓度为3％～30％。
  4. 根据权利要求1所述的不同含氧量的石墨烯量子点的制备方法，其特征在于，所述过氧化物为过氧化氢、过硫酸铵、过硫酸钠、过硫酸氢钾、过硼酸钠、过氧二苯甲酰、过氧二月桂酰中的至少一种。
  5. 根据权利要求1所述的不同含氧量的石墨烯量子点的制备方法，其特征在于，所述步骤二中，在所述提纯后还包括如下步骤：
    将提纯后的产物在溶剂中与还原剂进行反应，提纯，得到石墨烯量子点干粉。
  6. 根据权利要求1至5任意一项所述的不同含氧量的石墨烯量子点的制备方法，其特征在于，步骤三中所述梯度洗脱具体为：采用真空液相色谱法或者柱层析法进行梯度洗脱。
  7. 根据权利要求6所述的同含氧量的石墨烯量子点的制备方法，其特征在于，所述梯度洗脱使用的洗脱剂包括第一极性溶剂和第二极性溶剂，所述第一极性溶剂的极性大于所述第二极性溶剂的极性；所述第一极性溶剂包括：水、甲醇、乙醇、乙二醇、盐酸-甲醇溶液、四氢呋喃、甲酸、乙酸、乙腈、N，N-二甲基甲酰胺、乙醚、丙酮、硝基甲烷中的一种或多种；所述第二极性溶剂包括:环己烷、正己烷、石油醚、乙酸乙酯、碳酸二甲酯、二氯甲烷、三氯甲烷、四氯化碳中的一种或多种。
  8. 一种石墨烯量子点，其特征在于，其含氧量为2％～40％。
  9. 根据权利要求8所述的石墨烯量子点，其特征在于，其发射波长为550nm～750nm。
  10. 一种荧光材料，其特征在于，包括权利要求8或9所述的石墨烯量子点。
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108394886A (zh) * 2018-04-03 2018-08-14 中国工程物理研究院材料研究所 一种基于强碱切割氧化石墨制备碳量子点的方法、其产品及应用
CN109052365A (zh) * 2018-09-06 2018-12-21 苏州仁勤新材料有限公司 一种碳量子点的制备方法
CN111170311A (zh) * 2020-02-28 2020-05-19 太原理工大学 一种石墨烯量子点荧光薄膜及其制备方法
CN111982893A (zh) * 2019-05-21 2020-11-24 天津理工大学 一种基于石墨烯量子点的电化学发光检测日落黄的方法
CN113912050A (zh) * 2020-07-09 2022-01-11 Tcl科技集团股份有限公司 石墨烯量子点及其加工方法

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107557003A (zh) * 2017-09-28 2018-01-09 苏州轻光材料科技有限公司 一种蓝色荧光石墨烯量子点制备方法及在白光led应用
CN107986268A (zh) * 2017-12-13 2018-05-04 天津宝兴威科技股份有限公司 一种烷基功能化石墨烯量子点的制备方法
CN108946716A (zh) * 2018-09-30 2018-12-07 西安理工大学 一种无酸法制备石墨烯量子点的方法
CN111384267B (zh) * 2018-12-29 2021-09-10 Tcl科技集团股份有限公司 石墨烯量子点薄膜的制备方法和发光二极管及其制备方法
CN110540192B (zh) * 2019-09-11 2023-04-25 上海市第六人民医院 一种石墨烯量子点的制备方法
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CN113827734B (zh) * 2021-09-22 2023-08-01 青岛大学 具有多种生物医学功能的金属离子配位硼量子点复合载体的制备方法
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102660270A (zh) * 2012-05-03 2012-09-12 吉林大学 溶剂热法制备荧光石墨烯量子点的方法
CN102876327A (zh) * 2012-10-29 2013-01-16 吉林大学 一种用化学修饰法制备荧光颜色可控的石墨烯量子点的方法
CN103738941A (zh) * 2013-11-14 2014-04-23 盐城增材科技有限公司 一种石墨烯量子点的制备方法
CN103965867A (zh) * 2014-04-09 2014-08-06 上海大学 一种qd-led用石墨烯量子点包覆氧化锌的核壳结构量子点的制备方法
CN104477900A (zh) * 2014-12-15 2015-04-01 中国科学院武汉物理与数学研究所 一种微波法制备多色荧光石墨烯量子点的方法
CN104556004A (zh) * 2014-12-26 2015-04-29 西北大学 一种可控荧光石墨烯量子点的制备方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120171093A1 (en) * 2010-11-03 2012-07-05 Massachusetts Institute Of Technology Compositions comprising functionalized carbon-based nanostructures and related methods
CN102849724B (zh) * 2012-10-12 2014-08-20 上海交通大学 一种水溶性碳量子点的制备方法
CN103787319B (zh) * 2014-01-17 2015-10-14 深圳粤网节能技术服务有限公司 一种石墨烯量子点的大规模制备方法
CN104229790B (zh) * 2014-09-25 2016-05-18 深圳粤网节能技术服务有限公司 石墨烯量子点的制备方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102660270A (zh) * 2012-05-03 2012-09-12 吉林大学 溶剂热法制备荧光石墨烯量子点的方法
CN102876327A (zh) * 2012-10-29 2013-01-16 吉林大学 一种用化学修饰法制备荧光颜色可控的石墨烯量子点的方法
CN103738941A (zh) * 2013-11-14 2014-04-23 盐城增材科技有限公司 一种石墨烯量子点的制备方法
CN103965867A (zh) * 2014-04-09 2014-08-06 上海大学 一种qd-led用石墨烯量子点包覆氧化锌的核壳结构量子点的制备方法
CN104477900A (zh) * 2014-12-15 2015-04-01 中国科学院武汉物理与数学研究所 一种微波法制备多色荧光石墨烯量子点的方法
CN104556004A (zh) * 2014-12-26 2015-04-29 西北大学 一种可控荧光石墨烯量子点的制备方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108394886A (zh) * 2018-04-03 2018-08-14 中国工程物理研究院材料研究所 一种基于强碱切割氧化石墨制备碳量子点的方法、其产品及应用
CN109052365A (zh) * 2018-09-06 2018-12-21 苏州仁勤新材料有限公司 一种碳量子点的制备方法
CN111982893A (zh) * 2019-05-21 2020-11-24 天津理工大学 一种基于石墨烯量子点的电化学发光检测日落黄的方法
CN111170311A (zh) * 2020-02-28 2020-05-19 太原理工大学 一种石墨烯量子点荧光薄膜及其制备方法
CN113912050A (zh) * 2020-07-09 2022-01-11 Tcl科技集团股份有限公司 石墨烯量子点及其加工方法
CN113912050B (zh) * 2020-07-09 2023-11-14 Tcl科技集团股份有限公司 石墨烯量子点及其加工方法

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