CN112481698B - Method for improving nitrogen content of high-temperature high-pressure synthesized gem-grade diamond - Google Patents
Method for improving nitrogen content of high-temperature high-pressure synthesized gem-grade diamond Download PDFInfo
- Publication number
- CN112481698B CN112481698B CN202011135332.2A CN202011135332A CN112481698B CN 112481698 B CN112481698 B CN 112481698B CN 202011135332 A CN202011135332 A CN 202011135332A CN 112481698 B CN112481698 B CN 112481698B
- Authority
- CN
- China
- Prior art keywords
- carbon
- nitrogen
- temperature
- nitride powder
- carbon nitride
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/02—Elements
- C30B29/04—Diamond
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/082—Compounds containing nitrogen and non-metals and optionally metals
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B1/00—Single-crystal growth directly from the solid state
- C30B1/10—Single-crystal growth directly from the solid state by solid state reactions or multi-phase diffusion
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B1/00—Single-crystal growth directly from the solid state
- C30B1/12—Single-crystal growth directly from the solid state by pressure treatment during the growth
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
The invention belongs to the technical field of advanced material preparation, and provides a method for improving nitrogen content of high-temperature and high-pressure synthesized gem-grade diamond, which takes a carbon-nitrogen compound as a raw material, and adopts a molten salt auxiliary method to convert the carbon-nitrogen compound into carbon nitride powder containing C-N chemical bonds; the carbon nitride powder is used as raw material or additive, the metal alloy powder is used as catalyst, and the traditional cubic press is adopted to synthesize the gem-grade diamond monocrystal with high nitrogen content by a temperature gradient method. According to the diamond material with high nitrogen content, the carbon nitride material is used as a carbon source or an additive, nitrogen exists in the carbon source or the additive in a chemical bond mode, and a large number of NV color centers can be obtained under the conditions of high temperature and ultrahigh pressure; the carbon nitride material can not only provide nitrogen content, but also be used as a carbon source without introducing other impurities.
Description
Technical Field
The invention belongs to the technical field of advanced material preparation, relates to a method for preparing gem-grade diamond by a high-temperature high-pressure method, and particularly relates to a method for preparing high-nitrogen content diamond under the conditions of high temperature and high pressure by using carbon and nitrogen powder as a carbon source or a carbon source additive through purification treatment and prepressing forming.
Background
Diamond is the hardest substance in nature, and has a series of excellent properties such as high hardness, extremely high thermal conductivity, high refractive index, excellent chemical stability and the like. The artificial diamond is mainly synthesized by adopting a high-temperature high-pressure and chemical vapor deposition method, and is applied to drill bits, wire drawing dies and grinding materials or used as artware, ornaments and the like.
Diamonds can be classified into type i and type ii according to their nitrogen content. The diamond synthesized by artificial high temperature and high pressure is yellow (Ib type), and accounts for 98% of the total amount of natural diamondIt contains about 300ppm of nitrogen, and the nitrogen is present as a single substitutional atom, i.e., in a dispersed state. While the natural diamond has a nitrogen content of about 2X 103ppm, in which the nitrogen is present in the aggregated form, is mostly colorless (form Ia). The nitrogen concentrations and the existence forms of synthetic diamond and natural diamond are very different, resulting in many different properties of the two diamonds. The synthesis of the diamond with complete crystal form and high nitrogen content can provide an innovative technology for artificially synthesizing natural diamond and boron-coated nitrogen core diamond, and is helpful for deeply understanding and exploring the influence of nitrogen doping on the growth of the natural diamond. Meanwhile, the diamond types can be enriched, and the application field of the diamond is widened.
In recent years, researchers have attracted attention to the preparation of diamond single crystals by high temperature and high pressure and chemical vapor deposition methods, wherein the technology for synthesizing diamond by the high temperature and high pressure method is relatively mature. The basic principle is that under high temperature and high pressure, graphite is used as a carbon source, and alloy is used as a metal catalyst to synthesize diamond. Until now, the nitrogen content of diamond synthesized by an artificial high-temperature and high-pressure method is far different from that of natural diamond, and some researchers synthesize diamond with the nitrogen content as high as thousands of ppm, but the requirement on pressure is extremely high and no complete crystal form exists. Even if the nitrogen content of the synthesized diamond is similar to that of the natural diamond, the crystal size of the synthesized diamond is very small, so that the diamond has difficult measurement of properties and belongs to industrial-grade diamond single crystals. For this reason, there have been attempts to add NaN as a nitrogen-containing substance to an alloy solvent3、Ba(N3)2As an additive, the aim is to synthesize a gem-grade diamond single crystal with high nitrogen content. Researches for attempting to increase the nitrogen content of diamond single crystals and reduce the pressure and temperature for diamond synthesis by adding carbon nitride system materials so as to widen the functionalization of artificial diamonds are still rarely reported.
Disclosure of Invention
The invention aims to provide a process method for improving the nitrogen content of a gem-grade diamond synthesized by a high-temperature high-pressure method.
The technical scheme of the invention is as follows:
a method for improving the nitrogen content of a synthetic gem-grade diamond at high temperature and high pressure takes a carbon-nitrogen-hydrogen compound as a raw material, and the carbon-nitrogen-hydrogen compound is converted into carbon nitride powder containing C-N chemical bonds by a molten salt assisted method; synthesizing a gem-grade diamond monocrystal with high nitrogen content by a temperature gradient method by using carbon nitride powder as a raw material or an additive and metal alloy powder as a catalyst and adopting a traditional cubic press; the method comprises the following specific steps:
(1) synthesis of carbon nitride powder
The method for synthesizing the C-N material by adopting a molten salt assisted method comprises the following steps:
(1.1) high-purity halide salt ZnCl using a hydrocarbon of carbon and nitrogen as a raw material2NaCl, LiCl-KCl or KCl-NaCl is a molten salt medium; uniformly mixing a carbon-nitrogen-hydrogen compound and a molten salt medium in a ball mill according to a proportion; wherein the mass ratio of the low-melting-point halide salt to the high-melting-point halide salt in the molten salt medium is 1:3-3:1, and the mass ratio of the carbon-nitrogen hydride to the molten salt medium is 5% -50%;
(1.2) placing the ball-milled mixture in a nitrogen atmosphere at 5-15 ℃ for min-1Heating to 200-900 ℃ at the speed of (1) and keeping for 1 h;
(1.3) naturally cooling to room temperature, grinding the obtained solid, and completely removing inorganic salts and reaction residues by using a dilute hydrochloric acid solution with the mass fraction of 2% -20%;
(1.4) cleaning with hot deionized water and stirring for 2 hours, and finally filtering;
(1.5) washing the carbon nitride powder with distilled water to neutrality for a plurality of times, and then drying the carbon nitride powder in vacuum at 80 ℃ for 10-15h, or putting the carbon nitride powder into a water suspension solution and drying the carbon nitride powder in vacuum for 10-20h to obtain carbon nitride powder;
(2) high-temperature high-pressure synthesis of high-nitrogen content gem-grade diamond
Adding the carbon nitride powder obtained in the step (1) on the basis of a carbon source, wherein the mass ratio of the carbon nitride powder to the carbon source (such as graphite) is 20-100%, loading the treated raw material and the catalyst synthesis block into a pyrophyllite synthesis cavity, and controlling the pressure and the temperature; wherein the synthesis pressure is 4-10GPa, the temperature is 1000-1700 ℃, and the synthesis time is 10-48 hours; treating the synthesized sample in 30-60% dilute nitric acid at 100 ℃ for 20-40min, and then putting the synthesized crystal into a mixed solution of concentrated sulfuric acid and 96-98% concentrated nitric acid at a volume ratio of 1:10-1:1 for long-time fine purification treatment to remove impurities attached to the surface of the crystal; and finally, carrying out high-temperature annealing treatment on the high-nitrogen diamond under low pressure to convert the crystal into nearly colorless Ia type diamond, wherein the pressure is 2-4GPa, and the temperature is 1300-2000 ℃.
The invention has the beneficial effects that: according to the diamond material with high nitrogen content, the carbon nitride material is used as a carbon source or an additive, nitrogen exists in the carbon source or the additive in a chemical bond mode, and a large number of NV color centers can be obtained under the conditions of high temperature and ultrahigh pressure; the carbon nitride material can not only provide nitrogen content, but also be used as a carbon source without introducing other impurities.
Detailed Description
The following further describes the specific embodiments of the present invention in combination with the technical solutions.
(1) Selecting 1.0g, 7.4mmol of carbon nitrogen hydrogen compound adenine as raw material, ZnCl2NaCl as molten salt, in which ZnCl has a low melting point2ZnCl with the mass ratio of the high melting point NaCl to the high melting point NaCl being 1:1, namely 5.0g and 36.68mmol2And 5.0g, 85.56mmol of NaCl.
(2) Mixing adenine raw material and fused salt in a ball mill.
(3) Placing the mixture after ball milling into a crucible, and placing the crucible in a tube furnace at 5 ℃ for min in nitrogen atmosphere-1Heating to 800 ℃ at the speed of (1) and then preserving the heat for 1 h.
(4) After natural cooling, the solid obtained is ground and the inorganic salts and the residues of the reaction are removed completely with dilute hydrochloric acid solution. The mixture was stirred for 2 hours while washing with deionized water (80 ℃ C.), and finally filtered.
(5) Washing the mixture to neutrality by using distilled water for a plurality of times, and drying the mixture in vacuum at 80 ℃ for 12h to obtain the C-N material.
(6) And cleaning each assembly unit of the high-temperature and high-pressure equipment. Mixing the prepared carbon nitride powder with graphite according to the mass ratio of 50%, and prepressing and molding the mixture.
(7) Cold-pressing the metal catalyst into blocks, and then performing deoxidation treatment, wherein the mass ratio of the metal catalyst to the raw materials is 3: 7. the sample assembly block was placed in a drying oven (120 ℃ C.) for 2 hours to remove moisture adsorbed in the air in the assembly material.
(8) And taking out the sample assembly block, and placing the sample assembly block on a six-surface-top high-pressure device for diamond synthesis. The pressure was about 5.5GPa, the temperature was about 1450 ℃ and the time was 12 hours.
(9) After the crystal synthesis, the catalyst part wrapping the crystal is treated by heating acid and treated in hot dilute nitric acid (the concentration is 50%) at 100 ℃ for 30 min. Then the crystal is put into a mixed solution (volume ratio is 1: 1) of concentrated sulfuric acid and concentrated nitric acid for long-time fine boiling treatment to remove impurities attached to the surface of the crystal. Finally obtaining the gem-grade diamond with high nitrogen content.
Claims (2)
1. A method for improving the nitrogen content of a synthetic gem-grade diamond at high temperature and high pressure takes a carbon-nitrogen-hydrogen compound as a raw material, and the carbon-nitrogen-hydrogen compound is converted into carbon nitride powder containing C-N chemical bonds by a molten salt assisted method; synthesizing a gem-grade diamond monocrystal with high nitrogen content by a temperature gradient method by using carbon nitride powder as an additive and metal alloy powder as a catalyst and adopting a traditional cubic press; the method is characterized by comprising the following specific steps:
(1) synthesis of carbon nitride powder
The method for synthesizing the C-N material by adopting a molten salt assisted method comprises the following steps:
(1.1) high-purity halide salt ZnCl using a hydrocarbon of carbon and nitrogen as a raw material2NaCl, LiCl-KCl or KCl-NaCl is a molten salt medium; uniformly mixing a carbon-nitrogen-hydrogen compound and a molten salt medium in a ball mill according to a proportion; wherein the mass ratio of the low-melting-point halide salt to the high-melting-point halide salt in the molten salt medium is 1:3-3:1, and the mass ratio of the carbon-nitrogen hydride to the molten salt medium is 5% -50%;
(1.2) placing the ball-milled mixture in a nitrogen atmosphere at 5-15 ℃ for min-1Heating to 200-900 ℃ at the speed of (1) and keeping for 1 h;
(1.3) naturally cooling to room temperature, grinding the obtained solid, and completely removing inorganic salts and reaction residues by using a dilute hydrochloric acid solution with the mass fraction of 2% -20%;
(1.4) cleaning with hot deionized water and stirring for 2 hours, and finally filtering;
(1.5) washing the carbon nitride powder with distilled water to neutrality for a plurality of times, and then drying the carbon nitride powder in vacuum at 80 ℃ for 10-15h, or putting the carbon nitride powder into a water suspension solution and drying the carbon nitride powder in vacuum for 10-20h to obtain carbon nitride powder;
(2) high-temperature high-pressure synthesis of high-nitrogen content gem-grade diamond
Adding the carbon nitride powder obtained in the step (1) on the basis of a carbon source, wherein the mass ratio of the carbon nitride powder to the carbon source is 20-100%, loading the treated raw material and the catalyst synthesis block into a pyrophyllite synthesis cavity, and controlling the pressure and the temperature; wherein the synthesis pressure is 4-10GPa, the temperature is 1000-1700 ℃, and the synthesis time is 10-48 hours; treating the synthesized sample in 30-60% dilute nitric acid at 100 ℃ for 20-40min, and then putting the synthesized crystal into a mixed solution of concentrated sulfuric acid and 96-98% concentrated nitric acid at a volume ratio of 1:10-1:1 for long-time fine purification treatment to remove impurities attached to the surface of the crystal; finally, carrying out high-temperature annealing treatment on the high-nitrogen diamond under low pressure to convert the crystal into nearly colorless Ia type diamond, wherein the pressure is 2-4GPa, and the temperature is 1300-2000 ℃;
the carbon-nitrogen-hydrogen compound is adenine.
2. The method for increasing the nitrogen content of a high temperature high pressure synthetic gem grade diamond as claimed in claim 1, characterized in that the carbon source is graphite.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011135332.2A CN112481698B (en) | 2020-10-22 | 2020-10-22 | Method for improving nitrogen content of high-temperature high-pressure synthesized gem-grade diamond |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011135332.2A CN112481698B (en) | 2020-10-22 | 2020-10-22 | Method for improving nitrogen content of high-temperature high-pressure synthesized gem-grade diamond |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112481698A CN112481698A (en) | 2021-03-12 |
| CN112481698B true CN112481698B (en) | 2022-04-12 |
Family
ID=74926952
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011135332.2A Active CN112481698B (en) | 2020-10-22 | 2020-10-22 | Method for improving nitrogen content of high-temperature high-pressure synthesized gem-grade diamond |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112481698B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113441088B (en) * | 2021-08-18 | 2023-04-11 | 张相法 | Cubic boron nitride-diamond polycrystalline sintered body and manufacturing process thereof |
| CN114950271B (en) * | 2022-05-16 | 2023-04-14 | 湖南良诚新材料科技有限公司 | Preparation method of diamond monocrystal |
| CN117026356A (en) * | 2023-08-23 | 2023-11-10 | 山东省科学院新材料研究所 | Preparation method of nitrogen-doped diamond monocrystal |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109663543B (en) * | 2018-12-19 | 2023-02-24 | 郑州中南杰特超硬材料有限公司 | Preparation method for synthesizing polycrystalline diamond with boron-skin-nitrogen core through direct conversion |
-
2020
- 2020-10-22 CN CN202011135332.2A patent/CN112481698B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112481698A (en) | 2021-03-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112481698B (en) | Method for improving nitrogen content of high-temperature high-pressure synthesized gem-grade diamond | |
| KR101413653B1 (en) | A method for manufacturing SiC powders with high purity | |
| CN101308718B (en) | Rare earth - iron super magnetostriction material | |
| CN109252081A (en) | A kind of high-entropy alloy Binder Phase ultrafine tungsten carbide hard alloy and preparation method thereof | |
| CN112371148A (en) | Preparation method of novel catalyst for synthesizing diamond at high temperature and high pressure | |
| CN108557788B (en) | Low-energy-consumption black phosphorus single crystal preparation method | |
| CN109053175B (en) | Cerium-doped lutetium disilicate scintillation ceramic and preparation method thereof | |
| CN111074341A (en) | Method for preparing high-purity raw material | |
| CN105363386A (en) | High-temperature high-pressure preparation process for life diamond | |
| CN100366581C (en) | Making process of C/C heater for monocrystal silicon drawing furnace and polycrystal silicon smelting furnace | |
| CN105126853B (en) | One kind synthesis high-quality gem grade diamond large single crystal catalyst and preparation method thereof | |
| CN109663543B (en) | Preparation method for synthesizing polycrystalline diamond with boron-skin-nitrogen core through direct conversion | |
| CN1887803A (en) | Prepn process of heat isolating C/C screen for monocrystal silicon drawing furnace and polycrystal silicon smelting furnace | |
| CN107540411B (en) | Method for reducing residual silicon content in carbon fiber reinforced ceramic matrix composite | |
| CN108560053A (en) | The yttrium luetcium silicate scintillation material and its growing method that a kind of lanthanum, dysprosium, cerium are co-doped with | |
| CN110670136B (en) | Synthesis method of cubic boron nitride | |
| CN112981533A (en) | Method for growing aluminum nitride crystal by using metal aluminum and high-purity nitrogen as raw materials through PVT method | |
| CN114538387B (en) | Preparation method of high-purity tin telluride | |
| CN112064120B (en) | Seed crystal for large-size cultivation of diamond and preparation method thereof | |
| CN115573025A (en) | Method for growing artificial quartz crystal raw material for high-purity quartz sand with purity of more than 5N | |
| CN112495303B (en) | Self-sharpening diamond and preparation method thereof | |
| JPH0535084B2 (en) | ||
| RU2640788C1 (en) | Method for obtaining doped diamond monocrystal | |
| CN110922176A (en) | Production process of quartz ceramic crucible material | |
| JP2002018267A (en) | Graphite material for synthesizing semiconductor diamond and semiconductor diamond manufactured using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |