阅读说明：本技术 掺杂杂原子的纳米金刚石 (Nano-diamond doped with heteroatom ) 是由 间彦智明 牧野有都 鹤井明彦 刘明 西川正浩 于 2020-03-16 设计创作，主要内容包括：本发明提供掺杂杂原子的纳米金刚石,其掺杂有至少一种杂原子,且满足以下的(i)和/或(ii)的要件：(i)BET比表面积为20～900m～(2)/g；(ii)初级粒子的平均尺寸为2～70nm。(The invention provides a heteroatom-doped nano-diamondA stone doped with at least one heteroatom and satisfying the following requirements (i) and/or (ii): (i) the BET specific surface area is 20 to 900m 2 (ii)/g; (ii) the primary particles have an average size of 2 to 70 nm.)

1. A heteroatom-doped nanodiamond, doped with at least one heteroatom, and satisfying the following requirements (i) and/or (ii):

(i) the BET specific surface area is 20 to 900m²/g；

(ii) The primary particles have an average size of 2 to 70 nm.

2. The heteroatom-doped nanodiamond according to claim 1, wherein,

the hetero atom contains at least one selected from carbon group elements, phosphorus and boron.

3. The heteroatom-doped nanodiamond according to claim 1 or 2, having a fluorescence peak.

4. The heteroatom-doped nanodiamond according to any one of claims 1-3, wherein,

the fluorescence peak is from at least one heteroatom-vacancy center.

5. The heteroatom-doped nanodiamond according to any one of claims 1 to 4, wherein the heteroatom-doped nanodiamond emitting fluorescence is further doped with phosphorus and/or boron.

6. The heteroatom-doped nanodiamond according to any one of claims 1-5, having a fluorescence peak in the range of 720-770 nm, the heteroatom comprising silicon.

7. The heteroatom-doped nanodiamond according to any one of claims 1-5, having a fluorescence peak in the range of 580-630 nm, the heteroatom comprising germanium.

8. The heteroatom-doped nanodiamond according to any one of claims 1-5, having a fluorescence peak in the range of 590-650 nm, the heteroatoms comprising tin.

9. The heteroatom-doped nanodiamond according to any one of claims 1-5, having a fluorescence peak in the range of 540-600 nm, the heteroatom comprising lead.

10. The heteroatom-doped nanodiamond according to any one of claims 1-9, comprising fluorescence emission based on NV (nitrogen-vacancy) centers.

11. The heteroatom-doped nanodiamond according to any one of claims 1-10, wherein,

the shape of the nano-diamond is spherical, ellipsoid or polyhedral.

12. The heteroatom-doped nanodiamond according to any one of claims 1 to 11, wherein the carbon content is 70 to 99 mass%, the hydrogen content is 0.1 to 5 mass%, and the nitrogen content is 0.1 to 5 mass%.

13. The heteroatom-doped nanodiamond according to any one of claims 1 to 12, wherein the ratio (D/G) of the peak area (D) of diamond to the peak area (G) of graphite in raman spectroscopy is 0.2 to 9.

14. The heteroatom-doped nanodiamond according to any one of claims 1 to 13, having a ratio (H/D) of a peak area (H) of surface hydroxyl groups (OH) to a peak area (D) of diamond in raman spectroscopy of 0.1 to 5.

15. The heteroatom-doped nanodiamond according to any one of claims 1 to 14, having a ratio (C/D) of a peak area (C) of a surface Carbonyl (CO) to a peak area (D) of diamond in raman spectroscopy of 0.01 to 1.5.

16. The heteroatom-doped nanodiamond according to any one of claims 1-15, having at least one oxygen-containing functional group terminus and/or at least one hydrogen-containing functional group terminus.

17. The heteroatom-doped nanodiamond according to any one of claims 1-16, wherein,

concentration of at least one heteroatom-vacancy centre of 1X 10¹⁰/cm³The above.

Technical Field

The present invention relates to heteroatom doped nanodiamonds.

Background

Diamond has a luminescent center which is a fluorescent chromophore of nanometer size and chemical stability, and does not exhibit decomposition, discoloration, or scintillation in vivo, which is common in a fluorescent substance of an organic substance, and therefore, it is expected as a probe for fluorescence imaging. In addition, spin information of electrons excited in the luminescence center may be measured from the outside, and thus, the use as ODMR (Optically Detected Magnetic Resonance) or a qubit is expected.

An SiV center, which is one of the luminescence centers of diamond, has a peak called ZPL (Zero Phonon Level) in the luminescence spectrum (non-patent document 1).

Silicon-doped diamond is produced by a CVD (chemical vapor deposition) method or the like (patent documents 1 to 2).

Non-patent document 2 analyzes nanodiamonds in meteorites, but nanodiamonds having a Silicon-Vacancy (SiV) center have not been produced. Non-patent document 2 shows that the SiV center is thermodynamically stable in the nanodiamond with a size of 1.1nm to 1.8nm by simulation.

Fig. 1 of non-patent document 3 discloses nanodiamonds having SiV centers adjusted by a CVD method by AFM (atomic force microscope). In the upper right graph of fig. 1, the height (nm) on the vertical axis and the position (μm) on the horizontal axis are shown, and it is clear that the peak height is about 9nm, but the width (position) is at least 70 nm.

Non-patent document 4 discloses the following: as the seed solution, 3 to 4nm of nanodiamond was used, and grown on a silicon wafer by MWPECVD method to obtain nanodiamond having an average particle size of 73nm containing SiV centers.

Documents of the prior art

Patent document

Patent document 1: japanese Kokai 2014-504254

Patent document 2: japanese patent laid-open No. 2004-176132

Non-patent document

Non-patent document 1: e.neuettal.applied PHYSICS LETTERS 98,243107, 243107(2011)

Non-patent document 2: nat nanotechnol.2014jan; 9(1) 54-8.doi:10.1038/nnano.2013.255.Epub 2013 Dec 8.

Non-patent document 3: adv Sci Lett.2011 Feb 1; 4(2):512-515.

Non-patent document 4: diamond and Related Materials, Volume 65,2016, Pages 87-90

Disclosure of Invention

Problems to be solved by the invention

It is an object of the present invention to provide a novel nanodiamond doped with a heteroatom.

Means for solving the problems

The present invention provides the following heteroatom-doped nanodiamonds.

An item 1. a heteroatom-doped nanodiamond, which is doped with at least one heteroatom and satisfies the following requirements (i) and/or (ii):

(i) the BET specific surface area is 20 to 900m²/g；

(ii) The primary particles have an average size of 2 to 70 nm.

The heteroatom-doped nanodiamond of item 2. item 1, wherein,

the hetero atom contains at least one member selected from the group consisting of carbon group elements, phosphorus and boron.

Item 3 the heteroatom-doped nanodiamond of item 1 or 2, having a fluorescence peak.

Item 4 the heteroatom-doped nanodiamond according to any one of items 1 to 3, wherein,

the fluorescence peak is derived from at least one heteroatom-vacancy centre.

The heteroatom-doped nanodiamond according to any one of claims 1 to 4, wherein,

the heteroatom-doped nanodiamond that emits fluorescence is further doped with phosphorus and/or boron.

The heteroatom-doped nanodiamond according to any one of claims 1 to 5, having a fluorescence peak in a range of 720 to 770nm, wherein the heteroatom includes silicon.

The heteroatom-doped nanodiamond of any one of claims 1-5, having a fluorescence peak in the range of 580-630 nm, the heteroatom comprising germanium.

The heteroatom-doped nanodiamond of any one of claims 1-5, having a fluorescence peak in the range of 590-650 nm, the heteroatom comprising tin.

The heteroatom-doped nanodiamond according to any one of claims 1 to 5, having a fluorescence peak in a range of 540 to 600nm, the heteroatom including lead.

The heteroatom-doped nanodiamond of any one of claims 1-9, comprising fluorescence emission based on NV (nitrogen-vacancy) centers.

The heteroatom-doped nanodiamond according to any one of claims 1 to 10, wherein,

the shape of the nano-diamond is spherical, ellipsoid or polyhedron.

Item 12 the heteroatom-doped nanodiamond according to any one of items 1 to 11, wherein the carbon content is 70 to 99 mass%, the hydrogen content is 0.1 to 5 mass%, and the nitrogen content is 0.1 to 5 mass%.

The heteroatom-doped nanodiamond according to any one of claims 1 to 12, wherein the ratio (D/G) of the diamond peak area (D) to the graphite peak area (G) in Raman spectroscopy is 0.2 to 9.

The heteroatom-doped nanodiamond according to any one of claims 1 to 13, wherein a ratio (H/D) of a peak area (H) of a surface hydroxyl group (OH) to a peak area (D) of diamond in Raman spectroscopy is 0.1 to 5.

The heteroatom-doped nanodiamond according to any one of claims 1 to 14, wherein a ratio (C/D) of a peak area (C) of a surface Carbonyl (CO) to a peak area (D) of diamond in Raman spectroscopy is 0.01 to 1.5.

The heteroatom-doped nanodiamond according to any one of claims 1-15, having at least one oxygen-containing functional group terminus and/or at least one hydrogen-containing functional group terminus.

The heteroatom-doped nanodiamond of any one of claims 1-16, wherein the concentration of at least one heteroatom vcenter is 1 x 10¹⁰/cm³The above.

ADVANTAGEOUS EFFECTS OF INVENTION

A known method of growing a nanodiamond layer doped with a heteroatom such as Si or B by CVD treatment of undoped nanodiamond particles placed on a silicon substrate forms nanodiamond particles having a large average primary particle size and/or a small specific surface area, and the shape thereof is distorted.

On the other hand, for example, the heteroatom-doped nanodiamond produced by the detonation method is a nanodiamond particle having a small average primary particle size and/or a large specific surface area, is nano-sized, is chemically stable, and does not exhibit decomposition, discoloration, or scintillation in a living body, and thus is useful as a probe for fluorescence imaging. Further, spin information of electrons excited in a heteroatom V (vacancy, hole) luminescence center may be measured from the outside, and thus, the use as ODMR (Optically Detected Magnetic Resonance method) and a qubit is expected

Drawings

Fig. 1 shows (a) an image of a 738nm bright point, (b) a result of fluorescence measurement of the bright point in fig. 1(a), and (c) a result of XRD measurement of a sample after mixed acid and alkali treatment, of a nanodiamond obtained by using triphenyl silanol as a heteroatom compound and adding the amount of the triphenylsilanol in an amount of 1 mass% in terms of an external proportion. In FIG. 1B, a fluorescence sideband (shoulder) is present at about 750nm, but this sideband may not be present depending on the sample.

Detailed Description

The heteroatom-doped nanodiamond of the present invention satisfies the following requirements (i) and/or (ii):

(i) the BET specific surface area is 20 to 900m²/g；

(ii) The primary particles have an average size of 2 to 70 nm.

The heteroatom compound is a compound containing at least one heteroatom (atom other than carbon), and may be any of an organic compound and an inorganic compound.

The hetero atom is selected from B, P, Si, S, Cr, Sn, Al, Ge, Li, Na, K, Cs, Mg, Ca, Sr, Ba, Ti, Zr, V, Nb, Ta, Mo, W, Mn, Fe, Ni, Cu, Ag, Zn, Cd, Hg, Ga, In, Tl, Pb, As, Sb, Bi, Se, Te, Co, Xe, F, Y and lanthanides, preferably selected from Si, Ge, Sn, B, P, Ni, Ti, Co, Xe, Cr, W, Ta, Zr, Zn, Ag, Pb and lanthanides, more preferably selected from Si, Ge, Sn, B, P, Ni, Ti, Co, Xe, Cr, W, Ta, Zr, Zn, Ag and Pb

Preferred heteroatoms to be doped in the nanodiamond are carbon group elements selected from Si, Ge, Sn and Pb, B (boron), P (phosphorus), Ni, and more preferred heteroatoms are Si, B, P.

In a preferred embodiment, the nanodiamond of the present invention contains at least one of a carbon group element selected from Si, Ge, Sn and Pb, B, P, Ni, and at least one of other hetero atoms.

In another preferred embodiment, the nanodiamond of the present invention comprises at least one selected from Si, B, P, Ni, and comprises at least one of other hetero atoms. The number of the hetero atoms doped in the nanodiamond is preferably 1 to 5, more preferably 1 to 4, and further preferably 1,2, or 3.

The heteroatom-doped nanodiamond according to a preferred embodiment of the present invention has a fluorescence peak. The heteroatom-doped nanodiamond according to another preferred embodiment of the present invention includes at least one heteroatom V center, thereby having a fluorescence peak. The wavelength of the fluorescence emission peak is preferably 720 to 770nm, more preferably 730 to 760nm in the case where the hetero atom contains silicon, 580 to 630nm, more preferably 590 to 620nm in the case where the hetero atom contains germanium, 590 to 650nm, more preferably 600 to 640nm in the case where the hetero atom contains tin, and 540 to 600nm, more preferably 550 to 590nm in the case where the hetero atom contains lead.

In a preferred embodiment of the present invention, the doped nanodiamond, in which the heteroatom is a fluorescence emitting heteroatom-vacancy center other than phosphorus and boron, may be further doped with phosphorus and/or boron. It is considered that the introduction of these atoms (B and/or P) has an effect of adjusting the charge of the heteroatom-V center other than B and/or P and the defect (luminescence center) derived from the other doped heteroatom, thereby stabilizing the fluorescence. In addition, the heteroatom-doped nanodiamond of the present invention may also include fluorescence based on NV centres. The NV center is a luminescence center based on nitrogen and holes (vacancies), and has a broad fluorescence spectrum having a peak based on ZPL (zero phonon ray) in the vicinity of 575nm and/or 637nm, for example, a broad fluorescence spectrum having a wavelength of 550 to 800nm when excited at 532 nm. For example, doping with a hetero atom that does not directly relate to fluorescence of phosphorus, boron, or the like is preferable because the NV center intensity may be increased. In yet another preferred embodiment of the present invention, the fluorescence peak of nanodiamond with heteroatom Si comprises a peak of about 738nm called ZPL (Zero Phonon Level).

The concentration of at least one heteroatom V center in the heteroatom-doped nanodiamond of the present invention is preferably 1 × 10¹⁰/cm³Above, more preferably 2 × 10¹⁰～1×10¹⁹/cm³. The concentration of the heteroatom V center is a total concentration of two or more kinds of heteroatom V centers in the case where the nanodiamond includes the heteroatom V centers. The concentration of the heteroatom V center can be identified, for example, by using a confocal laser microscope or a fluorescence absorption spectrometer.Reference is made to the literature for determining the concentration of heteroatom V centers by fluorescence absorbance analysis (DOI 10.1002/pssa.201532174).

The BET specific surface area of the nano-diamond doped with the heteroatom is preferably 20-900 m²A concentration of 25 to 800m²(iv)/g, more preferably 30 to 700m²A specific preferred range is 35 to 600m²(ii) in terms of/g. The BET specific surface area can be determined by nitrogen adsorption. The BET specific surface area can be measured, for example, under the following conditions using a device such as BELSORP-mini II (manufactured by Microtrac BEL Co., Ltd.).

Determination of powder amount: 40mg of

Pre-drying: treating at 120 deg.C under vacuum for 3 hr

Measurement temperature: 196 ℃ (liquid nitrogen temperature)

The average size of primary particles of the nanodiamond doped with a hetero atom is preferably 2 to 70nm, more preferably 2.5 to 60nm, further preferably 3 to 55nm, and particularly preferably 3.5 to 50 nm. The average size of the primary particles can be determined from the analysis result of powder X-ray diffraction (XRD) and by the scherrer equation. Examples of the XRD measuring device include a fully automatic multifunction X-ray diffraction device (manufactured by japan corporation).

The carbon content of the heteroatom-doped nanodiamond of the present invention is preferably 70 to 99 mass%, more preferably 75 to 98 mass%, and further preferably 80 to 97 mass%.

The hydrogen content of the heteroatom-doped nanodiamond of the present invention is preferably 0.1 to 5 mass%, more preferably 0.2 to 4.5 mass%, and further preferably 0.3 to 4.0 mass%.

The nitrogen content of the heteroatom-doped nanodiamond of the present invention is preferably 0.1 to 5 mass%, more preferably 0.2 to 4.5 mass%, and further preferably 0.3 to 4.0 mass%.

The carbon, hydrogen, and nitrogen contents of the heteroatom-doped nanodiamond can be determined by elemental analysis.

The heteroatom content of the heteroatom-doped nanodiamond of the present invention is preferably 0.0001 to 10.0 mass%, more preferably 0.0001 to 5.0 mass%, and further preferably 0.0001 to 1.0 mass%. The heteroatom content can be measured, for example, by inductively coupled plasma emission spectrometry (ICP-AES), XRF, SIMS (secondary ion mass spectrometry), and the heteroatom-doped nanodiamond can be quantified by melting in an alkali and then making an acidic solution. In addition, in the case where the nanodiamond contains two or more kinds of heteroatoms, the content of the heteroatoms is the total content thereof.

The heteroatom-doped nanodiamond according to a preferred embodiment of the present invention may identify characteristic peaks of diamond, graphite, surface hydroxyl (OH), and surface Carbonyl (CO) in a raman-shifted pattern by raman spectroscopy. The characteristic peak of diamond in the Raman shift spectrum is 1100-1400 cm^-1The characteristic peak of the graphite is 1450-1700 cm^-1The characteristic peak of surface hydroxyl (OH) is 1500-1750 cm^-1The characteristic peak of surface Carbonyl (CO) is 1650-1800 cm^-1. The areas of characteristic peaks of diamond, graphite, surface hydroxyl (OH), surface Carbonyl (CO) are shown by raman spectroscopy. The laser wavelength of the Raman light source is, for example, 325nm or 488 nm. As the Raman spectrometer, a confocal micro-Raman spectrometer (for example, trade name: micro laser Raman spectrometer LabRAM HR Evolution, horiba, manufactured by horiba Ltd.) can be used.

In the heteroatom-doped nanodiamond according to a preferred embodiment of the present invention, the ratio (D/G) of the peak area (D) of diamond to the peak area (G) of graphite is preferably 0.2 to 9, more preferably 0.3 to 8, and further preferably 0.5 to 7.

In the heteroatom-doped nanodiamond according to a preferred embodiment of the present invention, the ratio (H/D) of the peak area (H) of the surface hydroxyl group (OH) to the peak area (D) of the diamond is preferably 0.1 to 5, more preferably 0.1 to 4.0, and further preferably 0.1 to 3.0.

In the heteroatom-doped nanodiamond according to a preferred embodiment of the present invention, the ratio (C/D) of the peak area (C) of the surface carbonyl group (CO) to the peak area (D) of the diamond is preferably 0.01 to 1.5, more preferably 0.03 to 1.2, and further preferably 0.05 to 1.0.

As a raman analysis method of nanodiamonds, reference can be made to literature (for example, Vadym n. mocalin et al, NATURE NANOTECHNOLOGY,7(2012)11-23, particularly fig. 3).

In another preferred embodiment of the present invention, the heteroatom-doped nanodiamond may have at least one oxygen functional group terminal and/or at least one hydrogen terminal on the surface thereof. Examples of the terminal oxygen functional group include OH, COOH and CONH₂C is O, CHO, etc., preferably OH and C is O, COOH. The hydrogen terminal includes an alkyl group having 1 to 20 carbon atoms.

The presence of at least one oxygen functional group terminal on the surface of the heteroatom-doped nanodiamond suppresses the aggregation of the nanodiamond particles, and is therefore preferable. The presence of at least one hydrogen termination on the surface of the heteroatom-doped nanodiamond is preferable because the Zeta (Zeta) potential is positive and stable and highly dispersed in an acidic aqueous solution.

In another preferred embodiment of the present invention, the heteroatom-doped nanodiamond of the present invention may also have a core-shell structure. The core of the heteroatom-doped nanodiamond of the core-shell structure is a nanodiamond particle doped with at least one heteroatom. Preferably, the core is a moiety that fluoresces with a heteroatom V center. The shell is a non-diamond coating layer and may contain sp2 carbon, preferably further containing oxygen atoms. The shell may also be a graphite layer. The thickness of the shell is preferably 5nm or less, more preferably 3nm or less, and further preferably 1nm or less. The shell may have a hydrophilic functional group on the surface.

The heteroatom-doped nanodiamond may be preferably manufactured by a detonation method. The shape of the doped nanodiamond is preferably spherical, ellipsoidal, or polyhedral close to them.

The circularity is a numerical value indicating the complexity of a figure drawn by an image or the like. The maximum value is 1 for the circularity, and the numerical value becomes smaller as the figure becomes more complex. The circularity can be obtained by analyzing a TEM image of the heteroatom-doped nanodiamond with image analysis software (e.g., winROOF) and using the following equation.

Roundness 4 π × (area) ÷ (length around) ÷ 2

For example, in the case of a perfect circle with a radius of 10, it is a calculation formula of "4 π × (10 × 10 × π) ÷ (10 × 2 × π) ^ 2". The roundness was 1 (maximum value). That is, for roundness, perfect circles are the least complex figures. The circularity of the nanodiamond doped with a dopant atom is preferably 0.2 or more, more preferably 0.3 or more, and further preferably 0.35 or more.

In a preferred embodiment of the present invention, the heteroatom-doped nanodiamond particle has a diamond structure including sp3 carbon and the doped heteroatom in the center, and the surface thereof is covered with an amorphous layer composed of sp2 carbon. In a further preferred embodiment, the outer side of the amorphous layer may be covered by an oxidized graphite layer. Further, a hydrated layer may be formed between the amorphous layer and the graphite oxide layer.

In a preferred embodiment of the present invention, the heteroatom-doped nanodiamond has a positive or negative Zeta potential. The Zeta potential of the nano-diamond doped with the heteroatom is preferably-70 to 70mV, and more preferably-60 to 30 mV.

The heteroatom-doped nanodiamond of the present invention may be produced by a production method including the steps of: a step of mixing an explosive composition comprising at least one explosive and at least one heteroatom compound; and exploding the obtained mixture in a closed container. Examples of the container include a metal container and a synthetic resin container. The explosive and heteroatom compound are preferably formed by pressing (compressing), filling (casting). Examples of the method for producing the explosive and the particles (dry powder) of the heteroatom compound include a crystallization method, a pulverization method, and a spray flash evaporation method.

In the case of forming an explosive composition by a pressing method or a filling method, the explosive and the heteroatom compound are mixed in a dry powder or molten state or mixed using a solvent. The state of the explosive when mixed with the heteroatom compound may be any combination of four kinds of the following:

explosive (dry powder) and heteroatom compound (dry powder)

Explosive (dry powder) and heteroatom compound (molten state)

Explosive (in molten state) and heteroatom compound (dry powder)

Explosive (in molten state) and heteroatom compound (in molten state)

The mixing of the explosive and the heteroatom compound may be carried out in any condition with or without a solvent, and may be formed by a pressing method or a filling method after the mixing.

The average particle diameter of the explosive or the heteroatom compound is preferably 10mm or less, more preferably 5mm or less, and still more preferably 1mm or less. The average particle size can be measured by a laser diffraction/scattering method, an optical microscope, or a raman method.

The product obtained by explosion can be further subjected to a purification step and a post-treatment step. The purification process may include one or both of mixed acid treatment and alkali treatment. The purification step is preferably a mixed acid treatment step.

If an explosive composition comprising an explosive and a heteroatom compound is exploded in a container, graphite, metal impurities, a heteroatom simple substance, a heteroatom oxide, and the like are generated in addition to the heteroatom-doped nanodiamond. Graphite and metal impurities can be removed by mixed acid treatment, and in the case where the hetero atom is a carbon group element such as Si, Ge, Sn, Pb, etc., a simple substance of the carbon group element (Si, Ge, Sn, Pb) and an oxide of the carbon group element (SiO)₂、GeO₂、SnO、SnO₂、PbO、PbO₂Etc.) can be removed by alkali treatment.

The mixed acid may be a mixed acid of concentrated sulfuric acid and concentrated nitric acid, and preferably includes concentrated sulfuric acid: concentrated nitric acid is mixed acid with the volume ratio of 1: 1. The temperature of the mixed acid treatment is 50-200 ℃, and the time of the mixed acid treatment is 0.5-24 hours.

Examples of the base include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. The temperature of the alkali treatment is 30-150 ℃, and the time of the alkali treatment is 0.5-24 hours.

The post-treatment process may include annealing, gas phase oxidation. Through annealing treatment, the nano gold doped with hetero atomsThe heteroatom doped in the diamond may meet a defect (vacacy) to form a heteroatom V center. In addition, the graphite layer formed on the surface of the heteroatom-doped nanodiamond may be thinned or removed by vapor phase oxidation. Although this is an optional step, the hole forming step may be performed before annealing. The hole forming step is performed by irradiation with an ion beam or an electron beam. Even if the hole forming step is not performed, the heteroatom V center can be formed by annealing, but more heteroatom V centers can be formed by annealing after the hole forming step. The upper limit of the hole density introduced by ion beam irradiation or electron beam irradiation is the concentration (> 1X 10) at which diamond is destroyed²¹/cm³Hole concentration of) about the lower limit, for example, 1 × 10¹⁶/cm³Above, further 1X 10¹⁸/cm³The above. The ion beam is preferably an ion beam of hydrogen (H) or helium (He). For example, the energy of the hydrogen ion beam is preferably 10 to 1500keV, and the energy of the helium ion beam is preferably 20 to 2000 keV. The energy of the electron beam is preferably 500 to 5000 keV.

The annealing temperature is preferably 800 ℃ or higher, and the annealing time is preferably 30 minutes or longer.

The gas phase oxidation may be carried out in an atmospheric atmosphere, and the gas phase oxidation temperature is preferably 300 ℃ or higher, and the gas phase oxidation time is 2 hours or longer.

The explosive is not particularly limited, and a known explosive can be widely used. Specific examples thereof include: trinitrotoluene (TNT), cyclotrimethylenetrinitramine (hexogen, RDX), cyclotetramethylenetetranitramine (octoxygen), trinitronitrobenzonitril (terbutamine), pentaerythritol tetranitrate (PETN), Tetranitromethane (TNM), triaminotrinitrobenzene, hexanitrostilbene, diaminodinitrobenzofuroxan, and the like, and these may be used singly or in combination of two or more.

The specific examples of the heteroatom compounds described below are merely examples, and known heteroatom compounds can be widely used.

In the case where the heteroatom is silicon, as the organic silicon compound, there may be mentioned:

lower alkyl-containing silanes such as acetoxytrimethylsilane, diacetoxydimethylsilane, triacetoxymethylsilane, acetoxytriethylsilane, diacetoxydiethylsilane, triacetoxyethylsilane, acetoxytripropropylsilane, methoxytrimethylsilane, dimethoxydimethylsilane, trimethoxymethylsilane, ethoxytrimethylsilane, diethoxydimethylsilane, triethoxymethylsilane, ethoxytriethylsilane, diethoxydiethylsilane, triethoxyethylsilane, and trimethylphenoxysilane;

trichloromethylsilane, dichlorodimethylsilane, chlorotrimethylsilane, trichloroethylsilane, dichlorodiethylsilane, chlorotriethylsilane, trichlorophenylsilane, dichlorodiphenylsilane, chlorotritylsilane, dichlorodiphenylsilane, dichloromethylphenylsilane, dichloroethylphenylsilane, chlorodifluoromethylsilane, dichlorofluoromethylsilane, chlorofluorodimethylsilane, chloroethyldifluorosilane, dichloroethylfluorofluorosilicone, chlorodifluoropropylsilane, dichlorofluoropropylsilane, trifluoromethylsilane, difluorodimethylsilane, fluorotrimethylsilane, ethyltrifluorosilane, diethyldifluorosilane, triethylfluorosilane, trifluoropropylsilane, fluoropropylsilane, trifluorophenylsilane, difluorodiphenylsilane, fluorotriphenylsilane, tribromomethylsilane, dibromodimethylsilane, bromotrimethylsilane, bromotriethylsilane, bromotrimethylsilane, dichlorodiphenylsilane, and a mixture of, Silanes having a halogen atom such as bromotripropylsilane, dibromodiphenylsilane, bromotriphenylsilane, etc.;

polysilanes such as hexamethyldisilane, hexaethyldisilane, hexapropyldisilane, hexaphenyldisilane, and octaphenylcyclotetrasilane;

silazanes such as triethylsilazane, tripropylsilazane, triphenylsilazane, hexamethyldisilazane, hexaethyldisilazane, hexaphenyldisilazane, hexamethylcyclotrisilazane, octamethylcyclotetrasilazane, hexaethylcyclotrisilazane, octaethylcyclotetrasilazane and hexaphenylcyclotrisilazane;

aromatic silanes obtained by introducing a silicon atom into an aromatic ring, such as silabenzene and disilabenzene;

hydroxyl-containing silanes such as trimethylsilanol, dimethylphenylsilanol, triethylsilanol, diethylsilanediol, tripropylsilanol, dipropylsilanediol, triphenylsilanol, and diphenylsilanediol;

alkyl-or aryl-substituted silanes such as tetramethylsilane, ethyltrimethylsilane, trimethylpropylsilane, trimethylphenylsilane, diethyldimethylsilane, triethylmethylsilane, methyltriphenylsilane, tetraethylsilane, triethylphenylsilane, diethyldiphenylsilane, ethyltriphenylsilane and tetraphenylsilane;

carboxyl-containing silanes such as triphenylsilyl carboxylic acid, trimethylsilylacetic acid, trimethylsilylpropionic acid, and trimethylsilylbutanoic acid;

siloxanes such as hexamethyldisiloxane, hexaethyldisiloxane, hexapropyldisiloxane, and hexaphenyldisiloxane;

silanes having an alkyl group or an aryl group and having a hydrogen atom, such as methylsilane, dimethylsilane, trimethylsilane, diethylsilane, triethylsilane, tripropylsilane, diphenylsilane, and triphenylsilane;

tetrakis (chloromethyl) silane, tetrakis (hydroxymethyl) silane, tetrakis (trimethylsilyl) methane, tetrakis (dimethylsilyl) silane, tetrakis (tris (hydroxymethyl) silyl) silane, tetrakis (nitrolmethyl) silane; and so on.

As the inorganic silicon compound, there may be mentioned: silicon oxide, silicon oxynitride, silicon nitride, silicon oxycarbide, silicon carbonitride, silane, or a carbon material doped with silicon, or the like. As the carbon material to be doped with silicon, graphite (graphite), activated carbon, carbon black, ketjen black, coke, soft carbon, hard carbon, acetylene black, carbon fiber, mesoporous carbon, and the like can be cited.

Examples of the boron compound include: inorganic boron compounds, organic boron compounds, and the like.

Examples of the inorganic boron compound include: orthoboric acid, diboron dioxide, diboron trioxide, tetraboron pentoxide, boron tribromide, tetrafluoroboric acid, ammonium borate, magnesium borate and the like.

Examples of the organoboron compound include: triethylborane, (R) -5, 5-diphenyl-2-methyl-3, 4-propanol-1, 3,2-Azoborane, triisopropyl borate, 2-isopropoxy-4, 4,5, 5-tetramethyl-1, 3, 2-dioxaborane, bis (hexenylglycolic acid) diboron, 4- (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane-2-yl) -1H-pyrazole, N- [4- (4,4,5, 5-tetramethyl-1, 2, 3-dioxaborane-2-yl) phenyl]Tert-butyl carbamate, phenylboronic acid, 3-acetylphenylboronic acid, boron trifluoride acetate complex, boron trifluoride sulfolane complex, 2-thiopheneboronic acid, tris (trimethylsilyl) borate, and the like.

Examples of the phosphorus compound include: inorganic phosphorus compounds, organic phosphorus compounds, and the like. Examples of the inorganic phosphorus compound include ammonium polyphosphate and the like.

As the organic phosphorus compound, there can be mentioned: trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, dimethylethyl phosphate, methyldibutyl phosphate, ethyldipropyl phosphate, 2-ethylhexyl di (p-tolyl) phosphate, bis (2-ethylhexyl) p-tolyl phosphate, tricresyl phosphate, bis (dodecyl) p-tolyl phosphate, tris (2-butoxyethyl) phosphate, tricyclohexyl phosphate, triphenyl phosphate, ethyldiphenyl phosphate, dibutylphenyl phosphate, phenylbisdodecyl phosphate, tolyldiphenyl phosphate, tricresyl phosphate, p-tolylbis (2,5, 5' -trimethylhexyl) phosphate, tolyl-2, 6-ditolyl phosphate, trixylyl phosphate, hydroxyphenyl diphenyl phosphate, trihexyl diphenyl phosphate, ditexyl phosphate, and the like, Phosphoric acid esters such as tris (t-butylphenyl) phosphate, tris (isopropylphenyl) phosphate, 2-ethylhexyl diphenyl phosphate, bis (2-ethylhexyl) phenyl phosphate, tris (nonylphenyl) phosphate, and phenyl bisneopentyl phosphate;

condensed phosphates such as 1, 3-phenylenebis (diphenyl phosphate), 1, 4-phenylenebis (dixylyl) phosphate, 1, 3-phenylenebis (3,5,5 '-trimethylhexyl phosphate), bisphenol a bis (diphenyl phosphate), 4' -biphenylbis (dixylyl) phosphate, 1,3, 5-phenylenetris (dixylyl) phosphate), and phosphites such as trimethyl phosphite, triethyl phosphite, triphenyl phosphite, and tricresyl phosphite;

phosphites such as 1, 3-phenylenebis (diphenyl phosphite), 1, 3-phenylenebis (dixylyl phosphite), 1, 4-phenylenebis (3,5,5 '-trimethylhexyl phosphite), bisphenol a bis (diphenyl phosphite), 4' -biphenylbis (dixylyl phosphite), 1,3, 5-phenylenetris (dixylyl phosphite).

As the germanium compound, there can be mentioned: organic germanium compounds such as methyl germane, ethyl germane, methyl trimethyl germanium, dimethyl germanium diacetate, tributyl germanium acetate, tetramethoxy germanium, tetraethoxy germanium, isobutyl germane, alkyl germanium trichloride, dimethyl amino germanium trichloride, etc., and nitrotriphenol complex (Ge, etc.)₂(ntp)₂O), catechol complex (Ge (cat)₂) Or aminopyrene complex (Ge)₂(ap)₂Cl₂) Germanium complex, germanium alcoholate such as germanium ethoxide and germanium tetrabutoxide.

Examples of the tin compound include: tin (II) oxide, tin (IV) oxide, tin (II) sulfide, tin (IV) sulfide, tin (II) chloride, tin (IV) chloride, tin (II) bromide, tin (II) fluoride, inorganic tin compounds such as tin acetate and tin sulfate, alkyl tin compounds such as tetramethyl tin, monoalkyl tin oxide compounds such as monobutyl tin oxide, dialkyl tin oxide compounds such as dibutyl tin oxide, aryl tin compounds such as tetraphenyl tin, organotin compounds such as dimethyl tin maleate, hydroxybutyl tin oxide and monobutyl tin tris (2-ethylhexanoate), and the like.

Examples of the nickel compound include: divalent nickel halides such as nickel (II) chloride, nickel (II) bromide and nickel (II) iodide, inorganic nickel compounds such as nickel (II) acetate and nickel (II) carbonate, and organic nickel compounds such as nickel bis (ethylacetoacetate) and nickel bis (acetylacetonate).

Examples of the titanium compound include: inorganic titanium compounds such as titanium dioxide, titanium nitride, strontium titanate, lead titanate, barium titanate, and potassium titanate, and tetraalkoxytitanium such as tetraethoxytitanium, tetraisopropoxytitanium, and tetrabutoxytitanium; tetraethylene glycol titanate, di-n-butyl bis (triethanolamine) titanate, diisopropoxytitanium bis (acetylacetonate), isopropoxytitanium octanoate, isopropyltitanium trimethacrylate, isopropyltitanium triacrylate, triisostearoyl titanium isopropoxide, isopropyl tridecylphenylsulfonyl titanium isopropoxide, tris (butylmethylphosphonato) titanium isopropoxide, tetraisopropyl bis (dilaurylphosphato) titanate, dimethylacryloyloxyacetyl titanate, diacryloyloxyacetoxy titanate, dioctylphosphato ethylene titanate, trioctylphosphonato titanium isopropoxide, tetraisopropyl bis (dioctylphosphato) titanate, tetraoctyl bis (ditridecylato) phosphite titanate, tetrakis (2) bis (ditridecylo) phosphite acyloxy) titanate, 2-diallyloxymethyl-1-butyl) titanate, bis (dioctylphosphoato) oxyacetoxy titanate, tris (dioctylphosphoato) ethylene titanate, isopropyl tri (N-dodecyl) benzenesulfonyl titanate, isopropyl trioctyl titanate, isopropyl dimethacryloyl isostearyl titanate, isopropyl isostearyldiacryloyl titanate, isopropyl trioctylphosphoato) titanate, isopropyl tricumylphenyl titanate, isopropyl tris (N-aminoethyl) titanate and other organic titanium compounds.

Examples of the cobalt compound include: cobalt inorganic acid salts, cobalt halides, cobalt oxide, cobalt hydroxide, cobaltosic octacarbonyl, cobaltosic tetracarbonyl, cobaltosic dodecacarbonyl, tricobalt nonalkarbonyl, etc., cobalt tris (ethylacetoacetate), cobalt tris (acetylacetonate), organic acid salts of cobalt (e.g., acetate, propionate, cyanate, naphthenate, stearate), and alkylsulfonic acid salts (e.g., C) such as methanesulfonate, ethanesulfonate, octanesulfonate, dodecylsulfonate, etc_6-18Alkyl sulfonates); benzenesulfonates, p-toluenesulfonates, naphthalenesulfonates, decylbenzenesulfonates, dodecylbenzenesulfonates and the like aryl sulfonates optionally substituted with alkyl (e.g.，C_6-18Alkyl-aryl sulfonates)), organic cobalt complexes, and the like. Examples of the ligand constituting the complex include OH (hydroxyl group), alkoxy (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), acyl (acetyl group, propionyl group, etc.), alkoxycarbonyl (methoxycarbonyl group, ethoxycarbonyl group, etc.), acetylacetonyl group, cyclopentadienyl group, halogen atom (chlorine, bromine, etc.), CO, CN, oxygen atom, H₂O (hydrated), phosphine (triarylphosphine such as triphenylphosphine), or NH₃(ammine compound), NO₂(nitro), NO₃And nitrogen-containing compounds such as (nitrate), ethylenediamine, diethylenetriamine, pyridine, and phenanthroline.

As the xenon compound, for example: XeF₂、XeF₄、XeF₆、XeOF₂、XeOF₄、XeO₂F₄Isofluoride, XeO₃、XeO₄And oxides, etc.; xe (OH)₆And its salt Ba₃XeO₆Etc.; high xenon acid H₄XeO₆And salts thereof Na₄XeO₆(ii) a Complex with Metal carbonyl M (CO)₅Xe (M ═ Cr, Mo, W), hydrates, and the like.

Examples of the chromium compound include: chromium acetylacetonate complexes such as chromium acetylacetonate, chromium alkoxides such as chromium (III) isopropoxide, organic chromium compounds such as chromium (II) acetate and chromium (III) hydroxydiacetate, chromium (II) tris (allyl) chromium, chromium (III) trimethacrylate, chromium (crotyl) tris (crotyl) bis (cyclopentadienyl) chromium (i.e., chromocene), chromium (pentamethylcyclopentadienyl) bis (i.e., decamethyldiocyclopentadienyl) chromium, chromium (bis (phenyl) bis (ethylbenzene) chromium, chromium (mesitylene), chromium (bis (pentadienyl) bis, chromium (2, 4-dimethylpentadienyl) bis (allyl) tricarbonyl, (cyclopentadienyl) (pentadienyl) chromium, chromium (1-norbornyl) chromium, (trimethylmethane) tetracarbonylchromium, chromium (butadiene) dicarbonyl, (butadiene) tetracarbonylchromium, and chromium (cyclooctatetraene).

Examples of the tungsten compound include: inorganic tungsten compounds such as tungsten trioxide, ammonium tungstate and sodium tungstate, and boron atom-coordinated tungsten complexes such as ethylboroethylidene ligands; carbon atom coordinated tungsten complexes such as carbonyl ligands, cyclopentadienyl ligands, alkyl ligands and olefin ligands; nitrogen atom-coordinated tungsten complexes such as pyridine ligands and acetonitrile ligands; phosphorus atom-coordinated tungsten complexes coordinated with phosphine ligands, phosphite ligands, and the like; and an organic tungsten compound such as a sulfur atom-coordinated tungsten complex coordinated with a diethylthiocarbamate ligand or the like.

Examples of thallium compounds include: inorganic thallium compounds such as thallium nitrate, thallium sulfate, thallium fluoride, thallium chloride, thallium bromide, and thallium iodide, trialkylalialium such as trimethylthallium, triethylthallium, and triisobutylthallium, arylthallium such as dialkylthallium halides, dialkylthallium alkenyls, dialkylthallium alkynyls, triphenylthallium, and tritolylalium, organic thallium compounds such as diarylthallium halides, thallium 2-ethylhexanoate, thallium malonate, thallium formate, thallium ethanolate, and thallium acetylacetonate.

Examples of the zirconium compound include: and organic zirconium compounds such as zirconium nitrate, zirconium sulfate, zirconium carbonate, zirconium hydroxide, zirconium fluoride, zirconium chloride, zirconium bromide, zirconium iodide, and the like, zirconium n-propoxide, zirconium n-butoxide, zirconium t-butoxide, zirconium isopropoxide, zirconium ethoxide, zirconium acetate, zirconium acetylacetonate, zirconium butoxyacetylacetonate, zirconium bisacetoacetate, zirconium ethylacetoacetate, zirconium bisacetoacetate (zirconium acetylacetonate bisbenzothiazoacetate), zirconium hexafluoroacetylacetonate, zirconium trifluoroacetoacetate, and the like.

Examples of the zinc compound include: diethyl zinc, dimethyl zinc, zinc acetate, zinc nitrate, zinc stearate, zinc oleate, zinc palmitate, zinc myristate, zinc laurate, zinc acetylacetonate, zinc chloride, zinc bromide, zinc iodide, zinc carbamate, and the like.

Examples of the silver compound include: organic silver compounds such as silver acetate, silver pivalate, silver trifluoromethanesulfonate, and silver benzoate; silver nitrate, silver fluoride, silver chloride, silver bromide, silver iodide, silver sulfate, silver oxide, silver sulfide, silver tetrafluoroborate, silver hexafluorophosphate (AgPF)₆) Silver hexafluoroantimonate (AgSbF)₆) And inorganic silver compounds, and the like.

Examples of the lead compound include: lead monoxide (PbO)Lead dioxide (PbO)₂) Lead (Pb)₃O₄) White lead (2 PbCO)₃·Pb(OH)₂) Lead nitrate (Pb (NO))₃)₂) Lead chloride (PbCl)₂) Lead sulfide (PbS), chrome yellow (PbCrO)₄、Pb(SCr)O₄、PbO·PbCrO₄) Lead carbonate (PbCO)₃) Lead sulfate (PbSO)₄) Lead fluoride (PbF)₂) Lead tetrafluoride (PbF)₄) Lead bromide (PbBr)₂) Lead iodide (PbI)₂) And inorganic lead compound, lead acetate (Pb (CH)₃COO)₂) Lead tetracarboxylate (Pb (OCOCH)₃)₄) Tetraethyl lead (Pb (CH)₃CH₂)₄) Tetramethyl lead (Pb (CH)₃)₄) Tetrabutyl lead (Pb (C)₄H₉)₄) And the like.

Examples of the aluminum compound include: inorganic aluminum compounds such as alumina, alkoxy compounds such as trimethoxyaluminum, triethoxyaluminum, isopropoxyaluminum, isopropoxydiethoxyaluminum, and tributoxyaluminum; acyloxy compounds such as triacetoxy aluminum, aluminum tristearate, and aluminum tributyrate; aluminum isopropoxide, aluminum sec-butoxide, aluminum tert-butoxide, aluminum tris (ethylacetoacetate), aluminum tris (hexafluoroacetylacetonate), aluminum tris (ethylacetoacetate), aluminum tris (n-propylacetoacetate), aluminum tris (isopropylacetoacetate), aluminum tris (n-butylacetoacetate), aluminum trisalicylaldehyde, aluminum tris (2-ethoxycarbonylphenoxide), aluminum tris (acetylacetonate), trialkylaluminum such as trimethylaluminum, triethylaluminum and triisobutylaluminum, arylaluminum such as dialkylaluminum halide, dialkylaluminum alkenylate, dialkylaluminum alkynylaluminum, triphenylaluminum and tritylaluminum, and organoaluminum compound such as diarylaluminum halide.

Examples of the vanadium compound include: vanadic acid, metavanadic acid, and alkali metal salts thereof such as inorganic vanadium compounds, alkoxides of triethoxy vanadic acid, pentaethoxy vanadic acid, tripentoxy vanadic acid, triisopropoxy vanadic acid, and the like; acetonates such as vanadyl bisacetoacetonate, vanadium acetylacetonate, vanadyl acetylacetonate, and vanadyl oxyacetoacetonate; organic vanadium compounds such as vanadium stearate, vanadium pivalate, vanadium acetate and the like.

Examples of the niobium compound include: halides such as niobium pentachloride and niobium pentafluoride, inorganic niobium compounds such as niobium sulfate, niobic acid, and niobate, and organic niobium compounds such as niobium alkoxides.

Examples of the tantalum compound include: TaCl₅、TaF₅Iso-inorganic tantalum compound, Ta (OC)₂H₅)₅、Ta(OCH₃)₅、Ta(OC₃H₇)₅、Ta(OC₄H₉)₅、(C₅H₅)₂TaH₃、Ta(N(CH₃)₂)₅And organic tantalum compounds.

As the molybdenum compound, for example: inorganic molybdenum compounds such as molybdenum trioxide, zinc molybdate, ammonium molybdate, magnesium molybdate, calcium molybdate, barium molybdate, sodium molybdate, potassium molybdate, phosphomolybdic acid, ammonium phosphomolybdate, sodium phosphomolybdate, silicomolybdic acid, molybdenum disulfide, molybdenum diselenide, molybdenum ditelluride, molybdenum boride, molybdenum disilicide, molybdenum nitride, molybdenum carbide, and organic molybdenum compounds such as molybdenum dialkyldithiophosphate and molybdenum dialkyldithiocarbamate.

Examples of the manganese compound include: inorganic manganese compounds such as hydroxides, nitrates, acetates, sulfates, chlorides, and carbonates of manganese; including manganese oxalate, manganese acetylacetonate, or manganese alkoxide organic compounds such as manganese methoxide, manganese ethoxide, manganese butoxide, etc.

Examples of the iron compound include: inorganic iron compounds such as iron (II) fluoride, iron (III) fluoride, iron (II) chloride, iron (III) chloride, iron (II) bromide, iron (III) bromide, iron (II) iodide, iron (III) iodide, iron (II) oxide, iron (III) oxide, iron (II, III) tetraoxide, iron (II) sulfate, iron (III) sulfate, iron (II) nitrate, iron (III) nitrate, iron (II) hydroxide, iron (III) hydroxide, iron (II) perchlorate, iron (III) perchlorate, iron (II) ammonium sulfate, iron (III) tungstate oxide, iron (III) tetravanadate, iron (II) selenide, iron (II) trioxide, iron (III) pentoxide, iron (II) sulfide, iron (III) sulfide, iron (II) phosphide, iron (III) phosphide and the like; organic iron compounds such as iron (II) acetate, iron (III) acetate, iron (II) formate, iron (III) tricarboxylate, iron (II) tartrate, iron (III) sodium tartrate, iron (II) lactate, iron (II) oxalate, iron (III) ammonium citrate, iron (III) laurate, iron (III) stearate, iron (III) tripalmitate, iron (II) hexacyanide, iron (III) bis (2, 4-pentanedione) iron (II) dihydrate, iron (III) tris (2, 4-pentanedione), iron (III) tris (oxalato) potassium, iron (III) tris (trifluoromethanesulfonate), iron (III) p-toluenesulfonate, iron (III) dimethyldithiocarbamate, iron (III) diethyldithiocarbamate, and ferrocene.

Examples of the copper compound include: organic copper compounds such as copper oxalate, copper stearate, copper formate, copper tartrate, copper oleate, copper acetate, copper gluconate, and copper salicylate, and inorganic copper compounds such as natural minerals such as copper carbonate, copper chloride, copper bromide, copper iodide, copper phosphate, hydrotalcite, stehitite, and mantle rock.

Examples of the cadmium compound include: inorganic cadmium compounds such as cadmium fluoride, cadmium chloride, cadmium bromide, cadmium iodide, cadmium oxide and cadmium carbonate, and organic cadmium compounds such as cadmium phthalate and cadmium naphthoate.

Examples of mercury compounds include: inorganic mercury compounds such as mercuric chloride, mercuric sulfate and mercuric nitrate, and organic mercury compounds such as methylmercury, methylmercury chloride, ethylmercury chloride, phenylmercury acetate, thimerosal, mercury p-chlorobenzoate and mercury acetate fluorescein.

Examples of the gallium compound include: organic gallium compounds such as tetraphenylgallium and tetrakis (3,4, 5-trifluorophenyl) gallium, and inorganic gallium compounds such as gallium oxoate, gallium halide, gallium hydroxide and gallium cyanide.

Examples of the indium compound include: organic indium compounds such as triethoxy indium, indium 2-ethylhexanoate, and indium acetylacetonate, and inorganic indium compounds such as indium cyanide, indium nitrate, indium sulfate, indium carbonate, indium fluoride, indium chloride, indium bromide, and indium iodide.

Examples of the arsenic compound include: arsenic trioxide, arsenic pentoxide, arsenic trichloride, arsenic pentachloride, arsenous acid, arsenic acid, and salts thereof, inorganic arsenic compounds such as sodium arsenite, ammonium arsenite, potassium arsenite, ammonium arsenate, and potassium arsenate, and organic arsenic compounds such as arsenous acid, phenylarsonic acid, diphenylarsonic acid, p-hydroxyphenylarsonic acid, and p-aminophenylarsonic acid, and salts thereof, sodium arsenate, and potassium arsenate.

Examples of the antimony compound include: antimony oxide, antimony phosphate, KSb (OH), NH₄SbF₆Inorganic antimony compounds, antimony esters with organic acids, cyclic alkyl antimonite esters, and organic antimony compounds such as triphenylantimony.

Examples of the bismuth compound include: organic bismuth compounds such as triphenylbismuth, bismuth 2-ethylhexanoate and bismuth acetylacetonate, and inorganic bismuth compounds such as bismuth nitrate, bismuth sulfate, bismuth acetate, bismuth hydroxide, bismuth fluoride, bismuth chloride, bismuth bromide and bismuth iodide.

Examples of selenium compounds include: organic selenium compounds such as selenomethionine, selenocysteine, and selenocystine, and inorganic selenium compounds containing alkali metal selenate such as potassium selenate and alkali metal selenite such as sodium selenite.

As the tellurium compound, for example: telluric acid and its salts, tellurium oxide, tellurium chloride, tellurium bromide, tellurium iodide and tellurium alkoxide.

Examples of the magnesium compound include: organic magnesium compounds such as magnesium monoisopropoxide ethyl acetoacetate, magnesium bis (ethyl acetoacetate), magnesium monoisopropoxide alkyl acetoacetate, and magnesium bis (acetylacetonate), and inorganic magnesium compounds such as magnesium oxide, magnesium sulfate, magnesium nitrate, and magnesium chloride.

Examples of the calcium compound include: organic calcium compounds such as calcium 2-ethylhexanoate, calcium ethoxide, calcium methoxide ethoxide, and calcium acetylacetonate, and inorganic calcium compounds such as calcium nitrate, calcium sulfate, calcium carbonate, calcium phosphate, calcium hydroxide, calcium cyanide, calcium fluoride, calcium chloride, calcium bromide, and calcium iodide.

As the heteroatom compound having a heteroatom of Li, Na, K, Cs, S, Sr, Ba, F, Y or a lanthanoid, a known organic or inorganic compound can be used.

The heteroatom compound may be used alone or in combination of two or more.

The proportion of the explosive in the mixture comprising the explosive and the heteroatom compound is preferably 80 to 99.9999 mass%, more preferably 85 to 99.999 mass%, further preferably 90 to 99.99 mass%, particularly preferably 95 to 99.9 mass%, and the proportion of the heteroatom compound is preferably 0.0001 to 20 mass%, more preferably 0.001 to 15 mass%, further preferably 0.01 to 10 mass%, particularly preferably 0.1 to 5 mass%. The content of the heteroatom in the mixture containing the explosive and the heteroatom compound is preferably 0.000005 to 10 mass%, more preferably 0.00001 to 8 mass%, even more preferably 0.0001 to 5 mass%, particularly preferably 0.001 to 3 mass%, most preferably 0.01 to 1 mass%.

The explosive and the heteroatom compound may be mixed in powder form when they are solid, may be melted, or may be dissolved or dispersed in an appropriate solvent. The mixing may be performed by stirring, bead mill, ultrasonic wave, or the like.

In a preferred embodiment, the explosive composition comprising an explosive and a heteroatom compound further comprises a cooling medium. The cooling medium may be in any form of solid, liquid, or gas. As a method of using a cooling medium, there is a method of detonating a mixture of an explosive and a heteroatom compound in a cooling medium. Examples of the cooling medium include inert gases (nitrogen, argon, and CO), water, ice, liquid nitrogen, an aqueous solution of an heteroatom-containing salt, and a crystalline hydrate. Examples of the heteroatom-containing salt include ammonium hexafluorosilicate, ammonium silicate, tetramethylammonium silicate, and the like. When the cooling medium is, for example, water or ice, it is preferably used about 5 times the weight of the explosive.

In a preferred embodiment of the present invention, the mixture containing the explosive and the heteroatom compound is converted into diamond based on compression caused by a shock wave under high-pressure and high-temperature conditions generated by the explosion of the explosive (detonation method). Upon detonation of the explosive, heteroatoms are introduced into the diamond lattice. The carbon source for the nanodiamond may be an explosive and an organic heteroatom compound, but in case the mixture comprising an explosive and a heteroatom compound also comprises a carbon material without heteroatoms, this carbon material may also be the carbon source for the nanodiamond.

Examples

The present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 6

When the silicon-doped nanodiamonds were produced by the conventional method using TNT as an explosive and the dopants shown in table 1 as heteroatom compounds in the number of moles shown in table 1 based on the number of moles of TNT 1 under the conditions of temperature (K) and pressure (GPa) shown in table 1, nanodiamonds doped with silicon in the proportions shown in table 1 could be obtained.

The names and structural formulae of dopant molecules (silicon compounds) 1 to 6 for doping silicon are shown below.

Dopant molecule 1: silabenzene (silline)

Dopant molecule 2: tetramethylsilane (SiMe)₄)

Dopant molecule 3: tetrakis (nitroestermethyl) Silane (SiPETN)

Dopant molecule 4: tetrakis (dimethylsiloxy) silane (Si (SiMe)₂OH)₄)

Dopant molecule 5: tetrakis (trimethylsilyl) silane (Si (SiMe)₃)₄)

Dopant molecule 6: tetrakis (trimethylsilyl) methane (C (SiMe)₃)₄)

[ chemical formula 1]

[ Table 1]

As is clear from table 1, according to the present invention, a nanodiamond into which a large amount of silicon atoms is introduced can be obtained.

Example 7

Silicon-doped nanodiamonds were produced by a conventional method for producing nanodiamonds using about 60g of an explosive composition obtained by adding 10 parts by mass, 1 part by mass or 0.1 part by mass of triphenyl silanol as a heteroatom compound to 100 parts by mass of an explosive containing trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX). The obtained silicon-doped nanodiamond was subjected to the following treatment. The amount of triphenyl silanol added to the explosive is 10 mass%, 1 mass%, or 0.1 mass%.

(i) Mixed acid treatment

To 2800g of mixed acid (concentrated sulfuric acid: concentrated nitric acid: 11:1 by weight) was added 15g of nanodiamond obtained in the detonation test, and the mixture was treated at 150 ℃ for 10 hours while stirring.

(ii) Alkali treatment

1g of acid-mixed nanodiamond was added to 100mL of 8N aqueous sodium hydroxide solution, and the mixture was stirred and treated at 100 ℃ for 10 hours.

(iii) Annealing

The alkali-treated nanodiamond was annealed at 800 ℃ for 30 minutes in a vacuum atmosphere.

(iv) Gas phase oxidation

The annealed nanodiamond was subjected to gas phase oxidation treatment at 300 ℃ for 2 hours in an atmospheric atmosphere, thereby obtaining a silicon-doped nanodiamond according to the present invention.

(v) Fluorescence analysis

An aqueous suspension of 10 w/v% of the silicon-doped nanodiamond according to the present invention obtained by vapor phase oxidation was dropped on a glass substrate and dried to prepare an evaluation sample. The obtained evaluation sample was subjected to high-speed mapping using a micro-Raman spectrometer (trade name: LabRAM HR Evolution, horiba, manufactured by horiba Ltd.) to image a 738nm bright point. An image of 738nm bright spots of silicon-doped nanodiamond obtained using triphenyl silanol as the silicon compound and an addition amount of 1 mass% in terms of an external ratio is shown in fig. 1 (a). The fluorescence spectrum of the bright point in FIG. 1(a) is shown in FIG. 1 (b). A zero phonon line (fluorescence peak) at the center of SiV can be confirmed. The Si content of the obtained silicon-doped nanodiamond was 3.2 mass% when the amount of triphenyl silanol added in the explosive was 10 mass%, 0.15 mass% when the amount of addition was 1 mass%, and 0.03 mass% when the amount of addition was 0.1 mass%.

From fig. 1(b), it can be confirmed that the silicon-doped nanodiamond of the present invention has fluorescence of 738nm derived from the SiV center. Table 2 shows the average size and BET specific surface area of the primary particles of the obtained silicon-doped nanodiamond by XRD measurement.

[ Table 2]

Measurement of BET specific surface area

The device comprises the following steps: BELSORP-mini II (manufactured by Microtrac BEL Co., Ltd.)

Measurement of powder amount: 40mg of

Pre-drying: treating at 120 deg.C under vacuum for 3 hr

Measuring temperature: 196 ℃ (liquid nitrogen temperature)

Measurement of average size of Primary particles (powder X-ray diffraction (XRD))

The device comprises the following steps: full-automatic multifunctional X-ray diffraction device (manufactured by Kyowa Co., Ltd.)

Measurement of Si incorporation quantity (XRF)

The device comprises the following steps: fluorescent X-ray analyzer ZSX Primus IV, manufactured by Nippon Kogyo Co., Ltd

Example 8

A boron-doped nanodiamond was obtained in the same manner as in example 7, except that 1 part by mass of phenylboronic acid was used instead of 1 part by mass of triphenyl silanol in example 7.

Example 9

A phosphorus-doped nanodiamond was obtained in the same manner as in example 7, except that 1 part by mass of triphenylphosphine was used instead of 1 part by mass of triphenyl silanol in example 7.

Example 10

A nickel-doped nanodiamond was obtained in the same manner as in example 7, except that 1 part by mass of bis (acetylacetonato) nickel was used instead of 1 part by mass of triphenyl silanol in example 7.

Example 11

Nanodiamonds doped with silicon and boron were obtained in the same manner as in example 7, except that 0.5 part by mass of triphenyl silanol and 0.5 part by mass of phenyl boronic acid were used instead of 1 part by mass of triphenyl silanol in example 7.

Example 12

Silicon-and phosphorus-doped nanodiamonds were obtained in the same manner as in example 7, except that 0.5 part by mass of triphenyl silanol and 0.5 part by mass of triphenyl phosphine were used instead of 1 part by mass of triphenyl silanol in example 7.