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  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
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  • C09K11/00—Luminescent materials, e.g. electroluminescent or chemiluminescent
  • C09K11/08—Luminescent materials, e.g. electroluminescent or chemiluminescent containing inorganic luminescent materials
  • C09K11/65—Luminescent materials, e.g. electroluminescent or chemiluminescent containing inorganic luminescent materials containing carbon
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
  • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
  • H01M4/624—Electric conductive fillers
  • H01M4/626—Metals
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
  • H01M4/90—Selection of catalytic material
  • H01M4/92—Metals of platinum group
  • H01M4/925—Metals of platinum group supported on carriers, e.g. powder carriers
  • H01M4/926—Metals of platinum group supported on carriers, e.g. powder carriers on carbon or graphite
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
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  • C01P2002/00—Crystal-structural characteristics
  • C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
  • C01P2002/82—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by IR- or Raman-data
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2002/00—Crystal-structural characteristics
  • C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
  • C01P2002/86—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by NMR- or ESR-data

Definitions

• the present invention relates to a method for producing platinum-loaded single-crystal spherical carbon nanoparticles.
• Carbon nanoparticles are nanoparticles made of carbon atoms, and those with a particle diameter of less than 10 nm are also called carbon quantum dots.
• Quantum dots are known to be made from metal elements such as CdSe and CdTe, and exhibit fluorescence. However, these quantum dots are not suitable for use inside the human body, and so alternative materials have been sought.
• carbon nanoparticles can be produced by either a top-down or bottom-up method.
• Known top-down methods for producing carbon nanoparticles include, for example, methods for producing carbon nanoparticles from carbon materials of at least micron size, such as graphite, carbon nanotubes, and diamond, using laser ablation, arc discharge, and electrochemical techniques.
• known bottom-up methods for producing carbon nanoparticles include, for example, a method known as the hydrothermal method, in which pure water or an organic solvent is heat-treated under high-temperature and high-pressure conditions, and a method that utilizes chemical vapor deposition (CVD).
• CVD chemical vapor deposition
• hydrophilization of the carbon nanoparticle surface is carried out by an oxidation reaction in the atmosphere, or by mixing a surfactant in an aqueous solution and dispersing the nanoparticles in the aqueous solution, followed by an oxidizing agent. Hydrophilization of carbon nanoparticles in an aqueous solution that also uses surfactants requires a washing process to remove the surfactant after treatment, and this cumbersome process has been an issue.
• Claim 1 of Patent Document 1 describes a carbon nanoparticle phosphor containing carbon atoms, oxygen atoms, nitrogen atoms, and optionally hydrogen atoms. Because of the C-N bond and C-O bond, the carbon nanoparticle phosphor can be dispersed in an aqueous solution.
• Claim 9 discloses that the carbon nanoparticle phosphor is produced by a method including a step of hydrothermal synthesis of a solution in which an organic substance selected from the group consisting of citric acid, benzoic acid, glucose, fructose, and sucrose, amines, and one or more selected from inorganic acids and acetic acid are dissolved in a water-soluble solvent.
• the spatial lattice which is structural information of the carbon nanoparticle phosphor, and the carbon nanoparticle phosphor carrying platinum are not disclosed.
• Patent Document 2 describes a carbon composite for oxygen reduction catalysts (claim 1) that contains nanosheet-shaped graphene oxide or a reduced product thereof and carbon quantum dots. It describes that the carbon quantum dots may be carbon obtained by a conventional hydrothermal reaction, for example, by heating an aqueous solution containing a carbon source compound such as citric acid and a nitrogen source compound such as ethylenediamine at a temperature equal to or higher than the boiling point of water (claim 6, [0031], etc.). However, it does not disclose that the carbon quantum dots are single crystal and spherical, or that platinum-loaded carbon quantum dots are disclosed.
• Patent Document 3 describes a method for producing luminescent nanocarbon (claim 1, [0013]) that includes a reaction step in which a raw material solution containing a carbon source compound and a nitrogen source compound is reacted by a solvothermal synthesis method or the like.
• This luminescent nanocarbon is produced by hydrothermal synthesis similar to the production method in Patent Document 1.
• it does not disclose that the luminescent nanocarbon is single-crystalline and spherical, or that platinum is supported on the luminescent nanocarbon.
• Patent document 4 describes a method for forming carbon dots, which includes (a) mixing carbon powder with sulfuric acid and nitric acid to form a carbon powder mixture; (b) heating the carbon powder mixture under reflux to form a refluxed carbon powder mixture, and then (c) cooling the refluxed carbon powder mixture; and (d) neutralizing the refluxed carbon powder mixture to form a neutralized carbon powder mixture containing solubilized carbon dots (claim 1, [0036]).
• the carbon powder is oxidized to a quantum size of 1.5 to 6 nm ([0037], [0038]).
• the carbon dots prepared by the above formation method have abundant carboxyl groups on the surface and may have negative charges on the carboxyl groups ([0048]).
• the carbon dots are different from the platinum-loaded single-crystalline spherical carbon nanoparticles of the present invention because they have abundant carboxyl groups on the surface.
• Patent document 4 also does not disclose that the carbon dots are single-crystalline and spherical, or that platinum is loaded on the carbon dots.
• Patent Document 5 which is owned by the applicant of the present application, describes a method for producing semiconductor microparticles (claim 1) by using a fluid processing device equipped with relatively rotating processing surfaces that can approach and separate.
• Specific examples of the semiconductor element are described as being elements selected from the group consisting of silicon, germanium, carbon and tin ([0037]). However, no specific examples are described in which the semiconductor element is carbon. Even based on Patent Document 5, it is not possible to obtain the platinum-loaded single-crystal spherical carbon nanoparticles of the present invention. Furthermore, Patent Document 5 does not disclose that the nanoparticles are single-crystal and spherical, or that they are loaded with platinum.
• Patent Document 6 which is owned by the same applicant as the present application, describes a method for producing metal-loaded carbon particles by using a fluid treatment device equipped with relatively rotating treatment surfaces that can approach and separate ([0221] to [0263]).
• a fluid treatment device equipped with relatively rotating treatment surfaces that can approach and separate ([0221] to [0263]).
• platinum-loaded carbon black is produced by reacting a mixture of carbon black and a reducing agent with a dinitrodiammine platinum nitrate solution.
• the carbon black is used as is as a raw material, and there is no disclosure that the carbon particles are single crystal and spherical.
• Patent document 7 describes a fuel cell including a surface nanostructure 3 having platinum catalyst nanoparticles 4 and carbon nanoparticles 5 (claim 1, figure 1, etc.). However, it does not disclose that the carbon nanoparticles are single crystal and spherical.
• Non-Patent Document 1 describes the synthesis of amine-terminated carbon quantum dots by reducing carbon tetrachloride with a hydride reducing agent such as lithium aluminum hydride to form carbon quantum dots, which are then reacted with an arylamine in the presence of a platinum catalyst.
• the carbon quantum dots in Non-Patent Document 1 have NH 2 groups on their surfaces, and therefore are different from the platinum-loaded single-crystal spherical carbon nanoparticles of the present invention.
• Non-Patent Document 1 does not disclose that the carbon quantum dots are single-crystal and spherical, or that platinum-loaded carbon quantum dots are disclosed.
• platinum-loaded single-crystalline spherical carbon nanoparticles can be produced by reacting a solution containing a carbon halide with a reducing agent containing the anion of an aromatic compound produced by mixing lithium, sodium or potassium with an aromatic compound, and then continuously reacting with a solution containing a platinum halide, and that the produced platinum-loaded single-crystalline spherical carbon nanoparticles can be used as a battery electrode with improved conductivity over conventional carbon nanoparticles, making it possible to increase the battery packing density, and can also be used as a non-toxic catalyst, thereby completing the present invention. That is, the present invention is as follows.
• a method for producing platinum-supported single-crystal spherical carbon nanoparticles in which platinum particles are supported on the surface of single-crystal spherical carbon nanoparticles comprising the steps of: A raw material solution of single-crystal spherical carbon nanoparticles containing a carbon halide is mixed with a reduced solution of platinum-supported single-crystal spherical carbon nanoparticles containing an anion of an aromatic compound produced from lithium, sodium or potassium and an aromatic compound, to produce single-crystal spherical carbon nanoparticles; and then continuously adding a platinum source liquid containing a platinum halide to the obtained mixture to produce platinum-supported single-crystalline spherical carbon nanoparticles.
• An apparatus comprising: a fluid pressure imparting mechanism for imparting pressure to a fluid to be processed; a first processing member; at least two processing members of a second processing member capable of moving relatively close to and away from the first processing member; and a rotation drive mechanism for relatively rotating the first processing member and the second processing member, At least two processing surfaces, a first processing surface and a second processing surface, are provided at positions facing each other in each of the processing parts, and each of the processing surfaces constitutes a part of a sealed flow path through which a fluid to be processed of the pressure is caused to flow, and two or more kinds of fluids to be processed, at least one of which contains a reactant, are mixed and reacted between the two processing surfaces,
• the second processing member has a pressure-receiving surface, and at least a part of this pressure-receiving surface is constituted by the second processing surface, and this pressure-receiving surface generates a force that moves the second processing surface in a direction away from the first
• [5] The manufacturing method described in [4], wherein the opening is located downstream of a point at which the flow of the fluid to be processed passed between the two processing surfaces becomes a laminar flow.
• [6] The method according to any one of [1] to [5], wherein the molar ratio of the lithium, sodium or potassium to the carbon halide is 7:1 to 4:1.
• the aromatic compound is at least one selected from the group consisting of biphenyl, naphthalene, 1,2-dihydronaphthalene, anthracene, phenanthrene, and pyrene.
• the platinum-loaded single crystal spherical carbon nanoparticle reduced solution has at least four chemical shift peaks in the range of 5.5 ppm to 6.5 ppm in the 1 H-NMR spectrum.
• the solvent contained in the reduced solution of the platinum-loaded single-crystalline spherical carbon nanoparticles is tetrahydrofuran, 2-methyltetrahydrofuran, or dimethoxyethane, each of which has a residual moisture content of 10 ppm or less.
• the manufacturing method of the present invention makes it possible to manufacture platinum particle-supported single-crystalline spherical carbon nanoparticles.
• Platinum-supported single-crystalline spherical carbon nanoparticles manufactured by the manufacturing method of the present invention are supported with platinum particles that have excellent electrical conductivity, which improves the electrical conductivity of the carbon nanoparticles.
• compound semiconductors formed from cadmium, selenium, tellurium, etc. are not toxic to living organisms, there is no need to recover them after use as catalysts or battery materials.
• they because they are spherical, they can be densely packed with electrode materials for solar cells and secondary ion batteries, and can be used as negative electrodes for lithium ion batteries, fuel cell catalysts, and electrode materials for solar cells.
• 1 shows an IR absorption spectrum of naphthalene anions in a reduced solution of platinum particle-supported single-crystal spherical carbon nanoparticles.
• 1 shows a 1 H-NMR spectrum of a reduced solution of platinum particle-supported single-crystal spherical carbon nanoparticles.
• 7 shows the 7 Li-NMR spectrum of the reduced solution of platinum particle-supported single-crystal spherical carbon nanoparticles.
• 1 shows a TEM observation image of platinum-supported single-crystal spherical carbon nanoparticles prepared in Example 1-1.
• Example 1 shows a TEM observation image of platinum supported on platinum-supporting single-crystal spherical carbon nanoparticles prepared in Example 1-1, and the measured value of the 5-plane lattice spacing.
• 1 shows an STEM observation image of platinum-loaded single-crystal spherical carbon nanoparticles prepared in Example 1-2, and a line analysis of platinum by STEM-EDS.
• 1 shows the IR spectrum and waveform separation spectrum (2800 cm ⁇ 1 to 3000 cm ⁇ 1 ) of the platinum-supported single-crystal spherical carbon nanoparticles prepared in Example 1-1.
• Example 1 shows the IR spectrum and waveform separation spectrum (900 cm ⁇ 1 to 1900 cm ⁇ 1 ) of the platinum-supported single-crystal spherical carbon nanoparticles prepared in Example 1-1.
• 1 shows the fluorescence spectrum of platinum-supported single-crystal spherical carbon nanoparticles prepared in Example 1-2.
• 1 shows an X-ray diffraction pattern of platinum-supported single-crystal spherical carbon nanoparticles prepared in Example 1-4.
• 3 shows an STEM observation image of platinum-loaded single-crystal spherical carbon nanoparticles prepared in Example 3-1, and a surface analysis of platinum by STEM-EDS.
• Platinum-supported single crystal spherical carbon nanoparticles produced by the production method of the present invention are single crystal spherical carbon nanoparticles on which platinum particles are supported.
• the single crystal spherical carbon nanoparticles contained in the platinum-supported single crystal spherical carbon nanoparticles are single crystal and spherical.
• the average particle diameter of the single crystal spherical carbon nanoparticles is preferably 1 nm to 200 nm. If the average particle diameter is 200 nm or more, it becomes difficult to achieve high-density packing when the platinum-supported single crystal spherical carbon nanoparticles are used as a secondary battery negative electrode material.
• the single crystal spherical carbon nanoparticles are hexagonal.
• the spatial lattice of this hexagonal crystal can have a simple lattice structure and a rhombohedral lattice structure.
• the single crystal spherical carbon nanoparticles may be spherical or approximately spherical.
• the average circularity calculated by the formula 4 ⁇ S/ Z2 using the perimeter (Z) and area (S) of a projected image of the single-crystal spherical carbon nanoparticles observed by a transmission electron microscope is 0.85 or more, more preferably 0.90 or more, and even more preferably 0.95 or more.
• the average particle size of the single-crystal spherical carbon nanoparticles is preferably 1.2 nm to 10 nm, more preferably 1.5 nm to 7 nm, and even more preferably 2 nm to 5 nm.
• the average particle size of the platinum particles is, for example, 1 nm to 10 nm, preferably 1.5 nm to 5 nm, more preferably 1 nm to 3 nm, and even more preferably 0.2 nm to 2 nm.
• carbon nanotubes since these do not have a band gap, excited electrons generated by excitation light and holes, which are electron vacancies left by the excited electrons, immediately recombine and do not produce fluorescence. For this reason, carbon made of carbon atoms having sp 2 hybrid orbitals needs to be able to generate a band gap by some method.
• One method for this is to cut the bond region of carbon atoms having sp 2 hybrid orbitals in the graphene layer and introduce bonds of carbon atoms having sp 3 hybrid orbitals that are generated by bonding with carbon atoms or elements other than carbon atoms.
• the bonds of carbon atoms having sp 3 hybrid orbitals can generate C-H bonds or C-O bonds by bonding hydrogen or oxygen to the ends of the graphene layer. Therefore, it is preferable to use carbon particles having a structure in which graphene layers constituting the single-crystal spherical carbon nanoparticles are stacked, with C-H bonds present within the graphene layers and C-O bonds present at the ends of the graphene layers.
• the surface functional groups of the single-crystal spherical carbon nanoparticles can be confirmed, for example, by the presence of absorption in the wave number region of 2800 cm -1 to 2950 cm -1 , which is assigned to the stretching vibration of the C-H bonds, and in the wave number region of 1000 cm -1 to 1100 cm -1 , which is assigned to the stretching vibration of the C-O bonds, in an IR absorption spectrum.
• the platinum-loaded single crystal spherical carbon nanoparticles of Example 1-1 show absorption peaks due to C-H bonds at 2932 cm -1 and 2957 cm -1 , 2856 cm -1 and 2871 cm -1 , and an absorption peak due to C-O bonds at 1056 cm -1 , confirming a structural change that contributes to the generation of a band gap due to carbon atoms having sp3 hybrid orbitals.
• the platinum-supported single crystal spherical carbon nanoparticles are preferably platinum-supported single crystal spherical carbon particles in which the area of an absorption peak (stretching vibration of C-O bond) at 1000 cm -1 to 1100 cm -1 obtained by waveform separation of the wave number range of 900 cm -1 to 1900 cm -1 in an IR absorption spectrum is 15% or less (ratio of C-O bond), more preferably 2% or more and 15% or less, even more preferably 2% or more and 10% or less, and even more preferably 2% or more and 8.5% or less of the total area in the wave number range of 900 cm -1 to 1900 cm -1.
• the platinum-supported single crystal spherical carbon nanoparticles are preferably spherical carbon nanoparticles that produce a fluorescence maximum in the wavelength range of 400 nm to 600 nm in the fluorescence spectrum.
• the platinum-supported single crystal spherical carbon particles are preferably platinum-supported single crystal spherical carbon nanoparticles in which the area of an absorption peak at 1300 cm -1 to 1400 cm -1 obtained by waveform separation of the wave number range of 900 cm -1 to 1900 cm -1 in an IR absorption spectrum is 10% or less (ratio of C-N bonds), more preferably 8% or less, and even more preferably 6.5% or less of the total area in the wave number range of 900 cm -1 to 1900 cm -1.
• Fluorescence of carbon nanoparticles is known to occur via three different mechanisms: (A) Control of the fluorescent color by controlling the physical factor of changing the band gap of electronic energy according to the particle size of carbon nanoparticles into which carbon atoms having sp3 hybrid orbitals have been introduced (known as the quantum effect). (B) By surface modification, which involves treating the carbon nanoparticle surface with various chemical substances, various substituents, such as alkyl groups and amino groups with different molecular chain lengths, are chemically bonded to the silicon nanoparticle surface, and the fluorescent color is controlled via the surface substituents. (C) The fluorescent color is controlled by chemical factors, utilizing composition changes mediated by oxygen and nitrogen contained in the carbon nanoparticles.
• the platinum-loaded single-crystal spherical carbon nanoparticles of the present invention generate fluorescence by the synergistic action of (A) the quantum effect mechanism and (C) the oxygen-mediated mechanism among the three mechanisms (A) to (C) above. This mechanism is different from that of the amino-terminated carbon nanoparticles of Non-Patent Document 1, which use the quantum effect mechanism (A) and the surface modification mechanism (B).
• the single-crystal spherical carbon nanoparticles of the present invention preferably generate a fluorescence maximum in the wavelength range of 400 nm to 600 nm.
• the present invention is a method for producing platinum-supported single-crystalline spherical carbon nanoparticles in which platinum particles are supported on the surface of single-crystalline spherical carbon nanoparticles, which comprises mixing a single-crystalline spherical carbon nanoparticle raw material solution (liquid B) containing halocarbon with a platinum-supported single-crystalline spherical carbon nanoparticle reduced solution (liquid A) containing an anion of an aromatic compound produced from lithium, sodium or potassium and an aromatic compound to produce single-crystalline spherical carbon nanoparticles, and then continuously adding a platinum raw material solution (liquid C) containing haloplatinum to the resulting mixture to produce platinum-supported single-crystalline spherical carbon nanoparticles.
• the platinum-supported single-crystalline spherical carbon nanoparticle raw material solution (liquid B) and the platinum raw material solution (liquid C) are mixed with the platinum-supported single-crystalline spherical carbon nanoparticle reduced solution (liquid A) in a thin film fluid formed between two processing surfaces arranged opposite to each other, which can approach and separate from each other, at least one of which rotates relative to the other, to continuously produce platinum-supported single-crystalline spherical carbon nanoparticles.
• the raw material for the single-crystal spherical carbon nanoparticles is not particularly limited as long as it is a substance that can precipitate single-crystal spherical carbon nanoparticles by reduction.
• the raw material is preferably carbon tetrahalide, more preferably carbon tetrachloride, carbon tetrabromide, carbon tetraiodide, etc., and even more preferably carbon tetrachloride, carbon tetrabromide, etc.
• Platinum raw material liquid (C liquid) The raw material for the platinum particles to be supported on the single-crystal spherical carbon nanoparticles is not particularly limited as long as it is a substance that can be reduced to support platinum particles on the surface of the single-crystal spherical carbon nanoparticles.
• Preferred are platinum halides, and preferred are chloroplatinic acid (IV) hexahydrate (H 2 PtCl 6.6H 2 O) and platinum chloride (IV) (PtCl 4 ).
• solvents for the platinum-supported single-crystal spherical carbon nanoparticle reduction solution (Solution A), the single-crystal spherical carbon nanoparticle raw material solution (Solution B) and the platinum raw material solution (Solution C) are not particularly limited as long as they can dissolve the single-crystal spherical carbon nanoparticle raw material and the platinum raw material, can reduce the platinum raw material to support platinum particles on the single-crystal spherical carbon nanoparticles, and are inert and do not affect the reduction reaction.
• Preferred examples of the solvent include ether, etc., more preferably tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,2-dimethoxyethane (DME), or a mixture thereof, and even more preferably THF or 2-methyltetrahydrofuran.
• THF tetrahydrofuran
• DME 1,2-dimethoxyethane
• the residual oxygen concentration in the solvent used in the present invention is less than 0.1 ppm.
• Platinum-loaded single-crystal spherical carbon nanoparticle reduction solution (solution A))
• the reducing substance contained in the platinum-loaded single-crystal spherical carbon nanoparticle reduction solution is not particularly limited as long as it can reduce the raw material of the single-crystal spherical carbon nanoparticles and the platinum raw material contained in the platinum-loaded single-crystal spherical carbon nanoparticle raw material solution and can precipitate platinum particles as platinum-loaded single-crystal spherical carbon nanoparticles.
• the reducing substance include a combination of metallic lithium, sodium or potassium with an aromatic compound, and more preferably a combination of metallic lithium with an aromatic compound.
• Aromatic compounds include, for example, those that can transfer one electron from metallic lithium to an aromatic compound to generate a lithium cation and an aromatic compound anion.
• the aromatic compound anion that has been transferred has one electron in the lowest unoccupied molecular orbital (LUMO) of the aromatic compound, and is therefore an anion radical.
• LUMO unoccupied molecular orbital
• the reduction potential of carbon tetrachloride is -1.9 V, so in order to reduce carbon tetrachloride to carbon nanoparticles, the potential of the aromatic compound anion must be lower than -1.9 V.
• the potential is the value relative to silver (Ag)/silver chloride (AgCl) as a reference electrode (reference electrode).
• aromatic compounds with a potential lower than -1.9 V include naphthalene (-2.53 V), biphenyl (-2.68 V), 1,2-dihydronaphthalene (-2.57 V), phenanthrene (-2.49 V), anthracene (-2.04 V), pyrene (-2.13 V), or mixtures thereof, and preferably naphthalene, biphenyl, etc.
• tetracene (-1.55 V) and azulene (-1.62 V) are not suitable for the reduction of carbon tetrachloride.
• the molar ratio of metallic lithium, sodium or potassium to the aromatic compound is, for example, 1:1 to 1:5, preferably 1:1 to 1:1.5, and more preferably 1:1 to 1:1.2.
• the molar ratio of metallic lithium, sodium or potassium to the raw material of the single crystal spherical carbon nanoparticles is, for example, 10:1 to 1.2:1, preferably 7:1 to 1.5:1, and more preferably 5:1 to 3:1. It is preferable to use metallic lithium, sodium or potassium in excess of the raw material of the platinum-supported single crystal spherical carbon nanoparticles. By using in excess, platinum-supported single crystal spherical carbon nanoparticles can be produced.
• the single crystal spherical carbon nanoparticles are not completely reduced, and halogen atoms derived from the raw material remain in the single crystal spherical carbon nanoparticles, and they are no longer spherical.
• the solvent for the platinum-supported single crystal spherical carbon nanoparticle reduction solution include the above-mentioned solvents used in the single crystal spherical carbon nanoparticle raw material solution.
• the concentration of metallic lithium in the platinum-supported single crystal spherical carbon nanoparticle reduction solution is not particularly limited, but is determined according to the molar ratio of the metallic lithium, sodium or potassium to the raw material of the single crystal spherical carbon nanoparticles.
• Alkaline metals can be dissolved in ether-based organic solvents in the presence of aromatic compounds, but the reducing power is obtained by aromatic compound anions generated by the transfer of electrons generated by dissolving alkali metals to the LUMO of aromatic compounds.
• the structure of the reducing solution that generates reducing power is preferably in a state where lithium cations (Li + ) generated after electron transfer to the aromatic compound and naphthalene anions (NPT ⁇ - ) are directly bonded by Coulomb force without a solvent (Li + ⁇ NPT ⁇ - ), and in a structure where the solvent THF is interposed between the metallic lithium cations and the naphthalene anions (Li + ⁇ THF ⁇ NPT ⁇ - ).
• This solution structure has the problem of reducing reducing power because the lithium cations (Li + ) and naphthalene anions (NPT ⁇ - ) are solvated and bonded to each other by Coulomb force in a mutually solvated structure (Li + ⁇ THF ⁇ THF ⁇ NPT ⁇ - ) at storage temperatures of 25° C. or higher.
• the temperature after production of the platinum-loaded single-crystalline spherical carbon nanoparticle reduced solution is controlled to be maintained at less than 10° C., and the bond between the naphthalene anions (NPT ⁇ - ) and lithium cations (Li + ) by Coulomb force can be stably controlled, thereby maintaining reducing power.
• the necessity of storing the reducing solution at low temperature is to maintain a state of high reducing power as described above and to suppress the size distribution of platinum-supported single crystal carbon nanoparticles. Furthermore, when aromatic anions with high reducing power are present in the solvent, it is preferable to store the reducing solution at low temperature in view of the stability of the solvent after the reduction solution is prepared. When the storage temperature of the reducing solution is high, if a cyclic ether such as THF is used as the solvent, the aromatic compound anion causes a reduction polymerization reaction of THF, etc.
• a ring-opened compound of THF generated by reduction of a halocarbon will be mixed into the single crystal spherical carbon nanoparticles, so it is preferable to suppress the polymerization reaction.
• polymerization reaction inhibitors for THF include phenol-based polymerization inhibitors that are added to suppress the generation of peroxides of cyclic ethers such as THF, and preferably BHT (2,6-di-tert-butyl-4-methylphenol).
• the solvent can be further stabilized by using a solvent with higher stability than THF, such as 2-methyltetrahydrofuran.
• the platinum-supported single-crystalline spherical carbon nanoparticles of the present invention can be produced, for example, by mixing a single-crystalline spherical carbon nanoparticle raw material liquid (Liquid B) and a platinum-supported single-crystalline spherical carbon nanoparticle reduced liquid (Liquid A) in a thin film fluid formed between two processing surfaces arranged opposite each other and capable of approaching and separating, at least one of which rotates relative to the other, and then continuously mixing this with a liquid containing the platinum raw material (Liquid C).
• Liquid B single-crystalline spherical carbon nanoparticle raw material liquid
• Liquid A platinum-supported single-crystalline spherical carbon nanoparticle reduced liquid
• the apparatus used in the manufacturing method of the present invention includes, for example, a fluid treatment device proposed by the applicant of the present application and described in JP 2009-112892 A.
• the apparatus includes a stirring tank having an inner peripheral surface with a circular cross section and a stirring tool attached to the inner peripheral surface of the stirring tank with a small gap therebetween, and the stirring tank has at least two fluid inlets and at least one fluid outlet.
• a first treated fluid containing one of the reactants among the treated fluids is introduced into the stirring tank from one of the fluid inlets, and a second treated fluid containing one of the reactants different from the reactant is introduced into the stirring tank from a flow path different from that of the first treated fluid from the other of the fluid inlets.
• At least one of the stirring tank and the stirring tool rotates at high speed relative to the other to make the treated fluid into a thin film state, and in this thin film, at least the reactants contained in the first treated fluid and the second treated fluid are reacted with each other.
• an apparatus based on the same principle as the fluid treatment device described in Patent Documents 6 and 7 can be mentioned.
• the single crystal spherical carbon nanoparticles are produced by mixing the single crystal spherical carbon nanoparticle raw material liquid (liquid B) and the platinum-loaded single crystal spherical carbon nanoparticle reduction liquid (liquid A) in the thin film fluid.
• the single crystal spherical carbon nanoparticles are produced in two steps, first producing graphene layers as the nuclei of the single crystal spherical carbon nanoparticles, and then stacking these layers together to grow the single crystal spherical carbon nanoparticles.
• platinum-loaded single crystal spherical carbon nanoparticles can be produced by mixing platinum raw material liquid (liquid C).
• platinum-loaded single-crystalline spherical carbon nanoparticles when carbon tetrachloride, carbon tetrabromide, or carbon tetraiodide is used as the raw material for single-crystalline spherical carbon nanoparticles and reduced with a platinum-loaded single-crystalline spherical carbon nanoparticle reducing solution to produce single-crystalline spherical carbon nanoparticles, lithium chloride, lithium bromide, or lithium iodide is generated as a by-product. These by-products have a high solubility in ether-based solvents, and therefore have the advantage of being easily separated from the platinum-loaded single-crystalline spherical carbon nanoparticles by centrifugation.
• the platinum-supported single-crystal spherical carbon nanoparticles produced by the production method of the present invention can be used, for example, as a non-toxic catalyst, a light-emitting element, a light-emitting material that emits fluorescence, a negative electrode for a lithium-ion battery, an electrode material for a solar cell, a fuel cell catalyst, and a bonding material for a substrate of a semiconductor device.
• TEM Observation A transmission electron microscope JEM-2100 (manufactured by JEOL Ltd.) was used for TEM observation of platinum-supported single crystal spherical carbon nanoparticles.
• the above-mentioned TEM observation sample was used as the sample.
• the observation conditions were an acceleration voltage of 200 kV and an observation magnification of 10,000 times or more.
• the particle size was calculated from the distance between the maximum outer circumferences of the platinum-supported single crystal spherical carbon nanoparticles observed by TEM, and the average value (average particle size) of the results of measuring the platinum-supported single crystal spherical carbon nanoparticle size for 50 particles was calculated.
• STEM-EDS analysis For elemental mapping and quantification of platinum-loaded single crystal spherical carbon nanoparticles by STEM-EDS analysis, an atomic resolution analytical electron microscope, JEM-ARM200F (manufactured by JEOL Ltd.), equipped with an energy dispersive X-ray analyzer, Centurio (manufactured by JEOL Ltd.) was used.
• the observation conditions were an acceleration voltage of 200 kV, an observation magnification of 50,000 times or more, and a beam diameter of 0.2 nm.
• IR absorption spectrum of the platinum-supported single crystal spherical carbon nanoparticles was measured by the attenuated total reflection (ATR) method using a Fourier transform infrared spectrophotometer FT/IR-6600 (manufactured by JASCO Corporation). The measurement conditions were a resolution of 4.0 cm -1 , an accumulation count of 128 times, a diamond prism (ATR PRO470-H, an accessory of FT/IR-6600) was used, and the incidence angle was 45°.
• ATR Attenuated total reflection
• the accumulation count was 128 times, and a diamond prism (PKS-D1F) (wide area: refractive index 2.4) was incorporated into the ATRPRO ONE, an accessory of FT/IR-6600, and the incidence angle was 45°.
• the infrared (IR) absorption spectrum measured for the THF solution of metallic lithium, which is the reducing solution, and the platinum-supported single crystal spherical carbon nanoparticles produced in the examples and comparative examples is referred to as the IR spectrum.
• the waveform separation was carried out by curve fitting using a spectrum analysis program attached to the control software of the FT/IR-6600 so that the residual sum of squares was 0.05 or less.
• naphthalene (Confirmation of the generation of aromatic compound anions by IR spectrum)
• the case of naphthalene will be described as an example of an aromatic compound.
• Metallic lithium was added to a THF solution in which naphthalene was dissolved, generating naphthalene anions, which are reducing species, and the generation was confirmed by IR absorption spectroscopy.
• the measurement sample was prepared by dropping a reducing solution onto a potassium bromide (KBr) plate in an argon atmosphere glove box, covering the dropped solution with another KBr plate, holding the sample in a MagHoldIR (manufactured by JUSCO Engineering), removing the sample from the argon atmosphere glove box, and immediately measuring the sample by a transmission method using a Fourier transform infrared spectrophotometer FT/IR-6600 (manufactured by JASCO Corporation).
• the measurement conditions were a resolution of 4.0 cm -1 and 8 times of accumulation.
• naphthalene (Confirmation of the production of aromatic compound anions by NMR spectroscopy) As an example of aromatic compound anion generation, naphthalene will be described.
• the generation of naphthalene anions can be determined by the chemical shift of nuclear magnetic resonance (NMR).
• NMR nuclear magnetic resonance
• 1 H-NMR focusing on hydrogen atoms, hydrogen atoms bonded to carbon atoms of naphthalene are divided into two types, H ⁇ and H ⁇ , and can be determined from the change in chemical shifts shown by these. Since naphthalene anions accept electrons generated by dissolving metallic lithium, it is necessary to evaluate the bond state with lithium cations. This allows evaluation focusing on lithium cations by 7 Li-NMR.
• the measurement sample was filled in a quartz sample tube with a reducing solution in an argon glove box, and then removed after sealing.
• the measurement of the lithium cation 7 Li-NMR spectrum and the hydrogen atom 1 H-NMR spectrum was performed at room temperature with a sample rotation frequency of 15 Hz.
• software No-D NMR (Ver.5) (manufactured by JEOL Ltd.) that can be used with only the reduction solution without using a deuterium solvent was used.
• THF was used as the solvent
• NMR spectrum measurement with this software was performed by automatically extracting the NMR spectrum of THF, and measuring the 1 H-NMR spectrum using this as a reference.
• LiCl lithium chloride
• the fluorescence spectrum of the platinum-supported single crystal spherical carbon nanoparticles was measured using a spectrofluorometer FT-6500 (manufactured by JASCO Corporation).
• the above-mentioned sample solution for TEM observation was used as the sample.
• the sample solution dispersed in THF was placed in a quartz cell (optical path length: 1 cm) in a glove box with an argon atmosphere, the top was sealed, and the cell was removed from the glove box and measured.
• the measurement conditions were an excitation bandwidth of 3 nm, a fluorescence bandwidth of 3 nm, a response of 0.1 seconds, a scanning speed of 100 nm/min, and a data acquisition interval of 0.5 nm.
• the circularity as an index for evaluating the sphericity of platinum-supported single crystal spherical carbon nanoparticles was calculated as follows.
• the circularity of platinum-supported single crystal spherical carbon nanoparticles was approximated as an ellipse by using TEM image software iTEM (manufactured by Olympus Soft Imaging Solutions GmbH) to image obtained by TEM observation.
• TEM image software iTEM manufactured by Olympus Soft Imaging Solutions GmbH
• S area
• 4 ⁇ S/ Z2 was calculated using the values of perimeter (Z) and area (S) to obtain the circularity.
• the average value of the major axis (D) of the ellipses was calculated as the average particle size. The measurement was performed for 50 independent platinum-supporting spherical carbon nanoparticles.
• X-Ray Diffraction For the XRD measurement, an EMPYREAN powder X-ray diffraction measurement device (manufactured by the Malvern Panalytical Division of Spectris Co., Ltd.) was used. The measurement conditions were: measurement range: 10 to 100 [°2 ⁇ ], Cu anticathode, tube voltage: 45 kV, tube current: 40 mA, and scan speed: 0.013°/min.
• Example 1 In Example 1, a THF solution (single crystal spherical carbon nanoparticle raw material liquid (liquid B)) in which carbon tetrachloride (CCl 4 ), a raw material for single crystal spherical carbon nanoparticles, was dissolved was reduced using a THF solution in which metallic lithium was dissolved in naphthalene (platinum-loaded single crystal spherical carbon nanoparticle reduction liquid (liquid A)) to produce single crystal spherical carbon nanoparticles, which were then continuously mixed with a THF solution of chloroplatinic acid (IV) hexahydrate (platinum raw material liquid (liquid C)) to continuously produce platinum-loaded single crystal spherical carbon nanoparticles without exposure to air.
• Table 1 shows the formulations for Examples 1-1 to 1-4.
• Example 1 The solvent used in Example 1 is ultra-dehydrated tetrahydrofuran (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) with a residual moisture content of 10 ppm or less.
• a platinum-supported single-crystalline spherical carbon nanoparticle reduced solution liquid A
• a single-crystalline spherical carbon nanoparticle raw material solution liquid B
• a platinum raw material solution liquid C
• the platinum-supported single-crystalline spherical carbon nanoparticle reduced solution (liquid A) was prepared by dissolving metallic lithium to a concentration of 0.0515 mol/L in a THF solution in which naphthalene was dissolved at a preparation temperature of 20°C and 0.0515 mol/L with a glass-coated magnetic stirrer.
• the single-crystalline spherical carbon nanoparticle raw material solution (liquid B) was prepared by dissolving carbon tetrachloride, which is a single-crystalline spherical carbon nanoparticle raw material, in THF and then stirring with a glass-coated magnetic stirrer for at least 60 minutes.
• the platinum raw material liquid (liquid C) was prepared by dissolving the platinum raw material chloroplatinic acid (IV) hexahydrate in THF and stirring the solution for at least 60 minutes with a Teflon-coated magnetic stirrer.
• CCl4 is carbon tetrachloride (manufactured by Kanto Chemical Co., Ltd.)
• Li is metallic lithium (manufactured by Kishida Chemical Co., Ltd.
• C10H8 is naphthalene (manufactured by Kanto Chemical Co., Ltd.)
• H2PtCl6.6H2O is chloroplatinic acid (IV) hexahydrate (manufactured by Kishida Chemical Co., Ltd.).
• FIG. 1c shows the result of subtracting the IR absorption spectrum of the solvent THF from the IR absorption spectrum of the THF solution in which only naphthalene is dissolved.
• FIG. 1b shows the result of subtracting the IR absorption spectrum of the solvent THF from the IR absorption spectrum of the naphthalene THF solution in which metallic lithium is dissolved.
• FIG. 1a shows the result of subtracting the IR absorption spectrum of FIG . 1c from the IR absorption spectrum of FIG. 1b by correcting the intensity of the IR absorption spectrum of FIG. 1c at 1508 cm ⁇ 1 so as to match the absorbance of FIG. 1b at 1508 cm ⁇ 1.
• the peaks at 1488 cm ⁇ 1 and 1183 cm ⁇ 1 confirmed in FIG. 1a indicate that naphthalene anions are generated by the transfer of electrons generated by the dissolution of metallic lithium to the LUMO of naphthalene.
• the particle size of the produced single crystal spherical carbon particles is distributed depending on the change in reducing power of the solution A. Therefore, it is preferable to check the reducing power.
• the absorption peak at 1183 cm ⁇ 1 is steep and can be measured as a single peak, so the reducing power can be clearly determined by the decrease in the intensity of this absorption peak, and it can be confirmed that the intensity of this absorption peak decreases significantly when the reducing power decreases.
• Naphthalene anion (NPT ⁇ - ) and lithium cation (Li + ) can exist in a state where they are bound via the solvent THF (NPT ⁇ - ⁇ THF ⁇ Li + ), or in a state where they are directly bound without THF (NPT ⁇ - ⁇ Li + ).
• the two peaks at 6.35 ppm and 6.4 ppm, and the two peaks at 5.9 ppm and 6.1 ppm are thought to reflect the states in which naphthalene anion and lithium cation are bound by Coulomb force in the presence of THF.
• the peak at 0 ppm was in a state in which naphthalene anions solvated with THF and lithium cations solvated with THF were bonded by Coulomb force (THF ⁇ NPT ⁇ - ⁇ THF) ⁇ (THF ⁇ Li + ⁇ THF) even if naphthalene anions were present.
• LiCl lithium chloride
• the prepared platinum-loaded single crystal spherical carbon nanoparticle reduced solution (liquid A), single crystal spherical carbon nanoparticle raw material solution (liquid B), and platinum raw material solution (liquid C) were mixed using a fluid treatment device described in Patent Document 6 by the applicant of the present application.
• the fluid treatment device described in Patent Document 6 is the device described in Figure 1 (B) of the same publication, in which the openings d20 and d30 of the second and third introduction parts are concentric ring shapes surrounding the central opening of the processing surface 2, which is a disk formed in a ring shape.
• a platinum-supported single crystal spherical carbon nanoparticle reduced solution (liquid A) was introduced between the processing surfaces 1 and 2 from the first introduction part d1, and while the processing part 10 was operated at a rotation speed of 700 to 5000 rpm, a single crystal spherical carbon nanoparticle raw material liquid (liquid B) was introduced between the processing surfaces 1 and 2 from the second introduction part d2, and the platinum-supported single crystal spherical carbon nanoparticle reduced solution and the single crystal spherical carbon nanoparticle raw material liquid were mixed in the thin film fluid, and single crystal spherical carbon nanoparticles were precipitated between the processing surfaces 1 and 2.
• a platinum raw material liquid (liquid C) was introduced between the processing surfaces 1 and 2 from the third introduction part d3, and mixed with the mixed fluid containing single crystal spherical carbon nanoparticles in the thin film fluid.
• Platinum particles were supported on the surface of the single crystal spherical carbon nanoparticles, and a discharge liquid containing platinum-supported single crystal spherical carbon nanoparticles (hereinafter, platinum-supported single crystal spherical carbon nanoparticle dispersion liquid) was discharged from between the processing surfaces 1 and 2 of the fluid processing device.
• the discharged platinum-loaded single-crystal spherical carbon nanoparticle dispersion was collected in a beaker via a vessel.
• Table 2 shows the operating conditions of the fluid treatment device.
• the introduction temperatures (liquid delivery temperatures) and introduction pressures (liquid delivery pressures) of liquid A, liquid B, and liquid C shown in Table 2 were measured using a thermometer and a pressure gauge installed in the sealed introduction paths (first introduction part d1, second introduction part d2, and third introduction part d3) leading between the processing surfaces 1 and 2.
• the introduction temperature of liquid A shown in Table 2 is the actual temperature of liquid A under the introduction pressure in the first introduction part d1
• the introduction temperature of liquid B is the actual temperature of liquid B under the introduction pressure in the second introduction part d2
• the introduction temperature of liquid C is the actual temperature of liquid C under the introduction pressure in the third introduction part d3.
• the liquid delivery temperature is 20°C, and the liquid delivery pressure is 0.1 MPaG or less.
• a wet cake sample was prepared from the platinum-loaded single-crystalline spherical carbon nanoparticle dispersion discharged from the fluid processing device and collected in a beaker.
• the preparation was carried out according to a conventional method, the discharged platinum-loaded single-crystalline spherical carbon nanoparticle dispersion was collected, and the platinum-loaded single-crystalline spherical carbon nanoparticles were precipitated from this collected liquid by centrifugation (30190G for 2 hours) to separate the supernatant. After that, ultrasonic cleaning with THF and precipitation were repeated, and the finally obtained platinum-loaded single-crystalline spherical carbon nanoparticles were dried at -0.10 MPaG at 25°C for 20 hours to obtain a dry powder.
• Figure 4 shows a TEM image of platinum-loaded single crystal spherical carbon nanoparticles produced in Example 1-1. Similar results were confirmed for platinum-loaded single crystal spherical carbon nanoparticles in Examples 1-2 to 1-4. Since lattice fringes were observed in one direction, it was confirmed that the single crystal spherical carbon nanoparticles were single crystals.
• the lattice spacing of single crystal spherical carbon nanoparticles the measured length value of 5 lattice plane spacing, 1580 pm, divided by 5 was 316 pm.
• the lattice spacing of the loaded platinum particles as shown in Figure 5, the measured length value of 5 lattice plane spacing, 1155 pm, divided by 5 was 231 pm. These were assigned to the carbon (003) plane and the platinum (111) plane, respectively.
• Figure 6 shows the STEM observation image of the platinum-loaded single crystal spherical carbon nanoparticles produced in Example 1-2, and the result of overlaying the detection intensity of the line analysis of the platinum particles by STEM-EDS.
• High platinum intensity was detected on the surface side of the platinum-loaded spherical carbon nanoparticles, and it was confirmed that platinum particles were loaded on the surface of the single crystal spherical carbon nanoparticles.
• Platinum was also detected inside the platinum single crystal spherical carbon nanoparticles. This shows that platinum particles of about 1 nm, which are finer than the generally known particle size of about 3 nm when platinum particles are loaded, are adsorbed and coated on the surface of the single crystal spherical carbon particles.
• (C—H bond) 7 shows the results of waveform separation of the region of wave numbers 2800 cm -1 to 3000 cm -1 in the IR spectrum measurement of the platinum-supported single crystal spherical carbon nanoparticles of Example 1-1.
• the absorption peaks at 2856 cm -1 and 2871 cm -1 and the absorption peaks at 2932 cm -1 and 2957 cm -1 are attributed to the CH 3 bond and CH 2 bond of the C-H bond, respectively, and it was confirmed that the platinum-supported single crystal spherical carbon nanoparticles were hydrogenated.
• the same was confirmed for Examples 1-1, 1-3, and 1-4.
• the numbers in parentheses indicate the relative area ratio.
• Example 8 shows the results of waveform separation of the wave number region of 900 cm -1 to 1900 cm -1 in the IR spectrum measurement of the platinum-supported single crystal spherical carbon nanoparticles of Example 1-1.
• the peak wave number of each band after waveform separation and the relative area ratio are shown in parentheses.
• the C-O bonds of platinum-loaded single crystal spherical carbon nanoparticles can be generated by moisture always controlled to 10 ppm or less when platinum-loaded single crystal spherical carbon nanoparticles are produced by a reduction reaction in ultra-dehydrated THF, a grade specified for residual moisture in THF of 10 ppm or less.
• the surface of platinum-loaded single crystal spherical carbon nanoparticles is formed from the loaded platinum particles, C-O bonds, and C-H bonds, and has the characteristic of being easily dispersible in organic solvents.
• the C-N bond is generated by reacting with the outermost surface of the graphene layer that was not protected by oxygen due to exposure to the air atmosphere during the cleaning and recovery work of the platinum-supported single crystal spherical carbon nanoparticles.
• the presence of the C-N bond also indicates the termination of the bond defects of the single crystal spherical carbon particles by nitrogen.
• the C-N bond has absorption in the wave number region of 1300 cm -1 to 1400 cm -1 , so that the band 5 with the peak wave number of 1371 cm -1 corresponds to the C-N bond, and the relative area ratio (ratio of C-N bonds) is 6.0%.
• the ratio of the C-N bond is preferably 10% or less. This C-N bond may not be detected when the C-O bond terminates the carbon atom bond defects.
• Figure 9 shows the fluorescence spectrum observed for the platinum-loaded single crystal spherical carbon nanoparticles of Example 1-2 at an excitation wavelength of 240 nm.
• the fluorescence peak wavelength was 420 nm, and it was confirmed that visible light fluorescence can be obtained by ultraviolet light of less than 300 nm.
• the change in the fluorescence peak wavelength in platinum-loaded single crystal spherical carbon nanoparticles is explained by the quantum effect (A) of the three mechanisms (A) to (C).
• the fluorescence peak wavelength of platinum-loaded single crystal spherical carbon nanoparticles is thought to shift to the short wavelength side because the band gap increases as the particle size of the single crystal spherical carbon nanoparticles decreases, and this is a result of the quantum effect mechanism (A).
• the single crystal spherical carbon nanoparticles of the present invention are not surface-modified with alkyl groups, amino groups, etc., and do not have the surface modification mechanism (B) of the three mechanisms. Therefore, it is thought that the fluorescence is generated by the synergistic effect of the oxygen-mediated mechanism (C) due to oxygen being bonded to the single crystal spherical carbon particles, and the quantum effect mechanism (A).
• the peaks with diffraction angles 2 ⁇ of 42.2° and 44.6° appear due to the simple lattice of the hexagonal structure, and the peak with diffraction angle 2 ⁇ of 43.3° appears due to the rhombohedral lattice.
• the spatial lattice when the spatial lattice is a simple lattice, it means that if two graphene layers are A and B, it has a layered structure such as ABABAB..., and in the rhombohedral lattice, it means that if three graphene layers are A, B, and C, they have a layered structure such as ABCABCABC.... Therefore, the presence of a diffraction peak at 2 ⁇ of about 43° obtained in FIG. 10 indicates that the spatial lattice of the single-crystal spherical carbon nanoparticles is a rhombohedral lattice.
• Table 3 shows the average particle size, average circularity, average lattice spacing of the graphene layers of the carbon particles, average lattice spacing of the platinum particles, ratio of C-O bonds obtained from IR spectra, and fluorescence peak wavelength measured at an excitation wavelength of 240 nm for the platinum-loaded single crystal spherical carbon nanoparticles of Examples 1-1 to 1-4.
• Comparative Example 1 The recipe of Comparative Example 1 was the same as that of Example 1 shown in Table 1, but platinum-loaded single-crystal spherical carbon nanoparticles were produced by lowering the disk rotation speed to 600 rpm and 500 rpm as shown in Table 4. Table 5 shows the results of the obtained platinum-loaded single-crystal spherical carbon nanoparticles. No change was observed in the crystal structure when the disk rotation speed was reduced to less than 700 rpm.
• Example 2 shows the results of platinum-supported single crystal spherical carbon nanoparticles when the platinum-supported single crystal spherical carbon nanoparticle reduced solution (liquid A) was prepared at 5° C. and the disk rotation speed was 5000 rpm to 2100 rpm.
• the compositions of the platinum-supported single crystal spherical carbon nanoparticle reduced solution (liquid A) and the single crystal spherical carbon nanoparticle raw material solution (liquid B) were the same as those in Example 1, and were produced under the conditions shown in Table 1.
• Table 6 shows the production conditions of Example 2, and the results of the obtained platinum-supported single crystal spherical carbon nanoparticles are as shown in Table 7.
• the higher the disk rotation speed the smaller the average particle size.
• Comparative Example 2 The recipe for Comparative Example 2 was the same as that for Example 1 shown in Table 1, but platinum-loaded single crystal spherical carbon nanoparticles were produced at a disk rotation speed of 700 rpm and 500 rpm and a temperature of the platinum-loaded single crystal spherical carbon nanoparticle reduction solution (Solution A) of 0° C. as shown in Table 8.
• Table 9 shows the results of the platinum-loaded single crystal spherical carbon nanoparticles produced.
• the average circularity of the platinum-loaded single crystal spherical carbon nanoparticles produced at a disk rotation speed of 700 rpm and 500 rpm and a solution A temperature of 5° C. was less than 0.8.
• Example 3 The formulations of the A, B and C solutions in Example 3 are shown in Table 10.
• Carbon tetrachloride has four chlorine atoms bonded to carbon atoms, so in order to remove all four chlorine atoms and reduce them to carbon particles, the metallic lithium and naphthalene in the platinum-supported single-crystal spherical carbon nanoparticle reduction solution (A solution) are required in a molar ratio of 4 times that of carbon tetrachloride.
• the metallic lithium and naphthalene molar ratio in the reduction solution is set to 1/8 times that of carbon tetrachloride, and the flow rate of the A solution reduction solution during production is set to 8 times that of carbon tetrachloride, in order to relatively lower the naphthalene concentration in the reaction solution during the production of platinum-supported single-crystal spherical carbon nanoparticles.
• the metallic lithium and naphthalene in the reduction solution are set to 4 times that of carbon tetrachloride, as in the chemical reaction.
• the flow rate ratio of the platinum-loaded single crystal spherical carbon nanoparticle reduced solution (solution A) to the single crystal spherical carbon nanoparticle raw material solution (solution B) was set to 1:1, and platinum-loaded single crystal spherical carbon nanoparticles were produced by changing the flow rates of solutions A and B.
• Table 10 shows the recipe for producing platinum-loaded single crystal spherical carbon nanoparticles
• Table 11 shows the production conditions.
• FIG 11 shows an STEM observation image of the platinum-loaded single crystal spherical carbon nanoparticles produced in Example 3-1, and the element distribution obtained by STEM-EDS. From these results, it was confirmed that platinum particles are uniformly loaded on the platinum-loaded single crystal spherical carbon nanoparticles, which is different from the case where platinum particles are randomly loaded on the single crystal spherical carbon nanoparticles as confirmed in Example 1-1 when the single crystal spherical carbon particle diameter is around 15 nm. It was also confirmed that platinum particles are uniformly loaded on the single crystal spherical carbon nanoparticles in Examples 3-2 and 3-3.
• single-crystal spherical carbon nanoparticles are produced in a solution, and platinum particles are continuously produced.
• Table 12 shows the results of the obtained platinum-supported single-crystal spherical carbon nanoparticles.
• the manufacturing method of the present invention makes it possible to manufacture platinum-loaded single-crystal spherical carbon nanoparticles.
• the manufactured platinum-loaded single-crystal spherical carbon nanoparticles have the advantage that they do not have the toxicity to living organisms that compound semiconductors formed from cadmium, selenium, tellurium, etc. have, and therefore do not need to be recovered after use as catalysts or electrode materials.
• they are spherical, they can be densely packed with electrode materials for solar cells and secondary ion batteries, and because platinum particles are supported, they can be used as negative electrodes for lithium ion batteries and electrode materials for solar cells, with improved conductivity in contact between carbon nanoparticles.

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