Diamond high-pressure inclusion and preparation method thereof

Abstract

The invention relates to the technical field of new materials, and provides a diamond high-pressure inclusion and a preparation method thereof.The diamond high-pressure inclusion comprises a diamond high-pressure cabin and a solid high-pressure-state material located in the diamond high-pressure cabin; the high-pressure-state material is a material under the condition that the pressure is greater than one atmospheric pressure; the preparation method comprises the following steps: carrying out high-temperature and high-pressure treatment on a target material and more than two layers of film-form carbon materials serving as main raw materials, the target material is distributed between two adjacent layers of carbon materials in the film form; the high-temperature and high-pressure treatment enables the carbon material to be converted into the diamond hyperbaric chamber wrapping the high-pressure target material. According to the method, the carbon material in a film form is used as a raw material, the internal pressure state of the synthesized diamond inclusion, the granularity, the volume fraction, the spatial distribution state and the like of the wrapped material can be adjusted according to requirements, and then highly-controllable batch preparation of the diamond high-pressure inclusion composite material is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of new materials, and in particular to a diamond high-pressure inclusion and a preparation method thereof. Background Art

[0002] Natural high-pressure diamond inclusions originate from geological minerals. They are formed when natural diamonds capture high-pressure inclusion materials during their formation in the Earth's mantle and carry them to the Earth's surface. Diamond's extreme strength allows inclusions to maintain a certain degree of high underground pressure even after reaching the surface, allowing the structure and properties of high-pressure materials to be preserved in the form of inclusions at atmospheric pressure. Therefore, they hold great research and application value. However, the material type and morphology of natural diamond inclusions cannot be controlled, and they are extremely rare and difficult to obtain.

[0003] Chinese patent application number 220210515692.8 discloses a method for preparing a high-pressure material that can be separated from a high-pressure device. This technology proposes mechanically mixing a carbon material with a target material and then converting the mixture into a diamond high-pressure inclusion under high temperature and pressure. While simple, this method suffers from difficulties in uniformly mixing the carbon material and the target material. This makes it difficult to control the spatial distribution and particle size of the high-pressure material in the resulting inclusion, and the success rate of completely encapsulating the target material is limited.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The present invention provides a diamond high-pressure inclusion and a preparation method thereof, which are used to solve the defects of the prior art diamond high-pressure inclusion, such as the difficulty in controlling the spatial distribution and particle size of high-pressure state materials and the limited success rate of completely encapsulating the target material.

[0006] In a first aspect, the present invention provides a method for preparing a diamond high-pressure inclusion, wherein the diamond high-pressure inclusion comprises a diamond high-pressure chamber and a solid high-pressure material located within the diamond high-pressure chamber; the high-pressure material comprises a material at a pressure greater than 1 atmosphere; the preparation method comprises: using a solid target material and two or more layers of thin-film carbon material as main raw materials and subjecting them to high-temperature and high-pressure treatment; the target material having a certain spatial distribution and / or a certain size is encapsulated between two adjacent layers of the thin-film carbon material.

[0007] The high temperature and high pressure treatment transforms the carbon material into the diamond high pressure chamber enclosing the high pressure material.

[0008] The present invention first wraps the target material with a certain spatial distribution and / or a certain size between two adjacent layers of carbon material in the form of a thin film. The overall structure can be recorded as a composite film, and the composite film is used as the main raw material for high temperature and high pressure treatment. In this way, the technical advantages of the film preparation process and the technical characteristics of high temperature and high pressure treatment to convert carbon into diamond can be utilized to achieve control of the spatial distribution and / or particle size of the high-pressure material in the diamond high-pressure inclusion.

[0009] Carbon materials suitable for the present invention include, but are not limited to, one or a combination of two or more of graphite, carbon black, graphene, fullerene, carbon nanotubes, glassy carbon, and amorphous carbon.

[0010] Target materials suitable for the present invention include, but are not limited to, metals, ceramics, and semiconductor materials.

[0011] According to the method for preparing the diamond high-pressure inclusion provided by the present invention, before the high-temperature and high-pressure treatment, the target material is completely wrapped by the thin-film carbon material, so that there is no gap between the two adjacent layers of the wrapped thin-film carbon material.

[0012] According to the method for preparing the diamond high-pressure inclusion provided by the present invention, the preparation of the raw material includes: firstly arranging the target material on the carbon material in the form of a thin film, and then arranging the carbon material in the form of a thin film.

[0013] The carbon material in thin film form is formed by a thin film preparation process, and the thin film preparation process includes one or more of physical vapor deposition, chemical vapor deposition, atomic layer deposition, and wet chemical method.

[0014] According to the method for preparing the diamond high-pressure inclusion provided by the present invention, the total thickness of the composite film composed of two adjacent layers of the carbon material in the form of thin films and the target material therebetween is denoted as D, and the value range of D is 10 nm to 50 μm.

[0015] The thickness of a layer of the thin film carbon material is denoted as d, and d is greater than or equal to 30% of D.

[0016] According to the diamond high-pressure inclusion provided by the present invention, the target material may be in the form of particles, rods, flakes, or a combination of two or more thereof.

[0017] Preferably, the target material comprises nanoparticles in a monodisperse state.

[0018] According to the method for preparing the diamond high-pressure inclusions provided by the present invention, the high-temperature and high-pressure treatment comprises: treating the raw material under conditions of 15 to 100 GPa and 1200 to 2500° C.; Preferably, the raw material is treated under conditions of 15 to 100 GPa and 1200 to 2500° C. for 1 to 20 minutes.

[0019] In the high temperature and high pressure process of the present invention, methods including but not limited to resistance heating, laser heating and other methods that can generate high temperature can be used.

[0020] The present invention uses a thin film carbon material as one of the raw materials, and can achieve the structure (phase) and pressure value of the diamond high-pressure inclusion by changing the pressure and temperature parameters in a high-temperature and high-pressure process.

[0021] The method for preparing the diamond high-pressure inclusion provided by the present invention is characterized in that the high-temperature and high-pressure treatment is carried out using a diamond anvil cell or a large-cavity press.

[0022] The method for preparing the diamond high-pressure inclusion provided by the present invention comprises: A thin film preparation process is used to form a first layer of carbon material in the form of a thin film; forming a target material on the first layer of thin film-shaped carbon material to obtain a composite layer; forming a second layer of carbon material in the form of a thin film on the composite layer using a thin film preparation process to obtain a composite film; After stacking more than one layer of composite film, high temperature and high pressure treatment is carried out and pressure is released to obtain the diamond high pressure inclusion. Taking the high temperature and high pressure treatment of one layer of composite film as an example, the process is as follows: Figure 1 shown.

[0023] In a second aspect, the present invention further provides a diamond high-pressure inclusion, which is prepared by the above-mentioned method for preparing a diamond high-pressure inclusion; Preferably, the high pressure material comprises nanoparticles in a monodisperse state.

[0024] The materials of two adjacent layers of carbon materials in the form of thin films are the same or different.

[0025] The present invention provides a diamond high-pressure inclusion and a preparation method thereof. The diamond high-pressure inclusion comprises a diamond high-pressure chamber and a solid high-pressure material located within the chamber; the high-pressure material comprises a material under a pressure greater than 1 atmosphere; the preparation method comprises: using a target material and two or more layers of thin-film carbon material as primary raw materials, subjecting the material to high-temperature and high-pressure treatment; distributing the target material between two adjacent layers of the thin-film carbon material; and converting the carbon material into a diamond high-pressure chamber encapsulating the high-pressure target material through the high-temperature and high-pressure treatment. By using thin-film carbon material as raw material, the present invention can adjust the internal pressure state of the synthesized diamond inclusion, the particle size, volume fraction, spatial distribution state, etc. of the included material according to demand, thereby achieving highly controllable batch production of diamond high-pressure inclusion composite materials.

[0026] The method of the present invention can obtain products spanning multiple scales from nanometer to centimeter level, and can meet different application purposes. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 This is a schematic diagram of the main process of preparing diamond high-pressure inclusions.

[0029] Figure 2 This is a transmission electron microscope photograph of a cross section of the carbon-gold-carbon composite film of Example 2 of the present invention.

[0030] Figure 3 This is a plane transmission electron microscope photograph of the carbon-gold-carbon composite film of Example 2 of the present invention.

[0031] Figure 4 1 is the electron energy loss spectrum of the carbon layer of Example 2 of the present invention.

[0032] Figure 5 This is a high-resolution transmission electron microscope photograph of the diamond high-pressure inclusion of Example 2 of the present invention, in which the diamond encapsulates gold nanoparticles in a high-pressure state.

[0033] Figure 6 This is a high-resolution transmission electron microscope photograph of the diamond high-pressure inclusion of Example 3 of the present invention, in which the diamond encapsulates gold nanoparticles in a high-pressure state. DETAILED DESCRIPTION

[0034] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0035] The following combination Figures 1 to 6 The present invention describes the diamond high pressure inclusion and the preparation method thereof.

[0036] If no specific techniques or conditions are specified in the examples, the experiments were carried out according to the techniques or conditions described in the literature in the field or according to the product instructions. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased through regular channels.

[0037] The following examples are given for describing the preferred embodiments of the present invention.

[0038] Example 1

[0039] A method for preparing a diamond high-pressure inclusion comprises the following steps: (1) A carbon target was selected and magnetron sputtering was used. The magnetron sputtering process parameters were as follows: RF sputtering power 200 W, time 2600 s, Ar pressure 20 mTorr, Ar gas flow rate 30 sccm, and a carbon layer with a thickness of 20 nm was sputtered on the polyvinyl alcohol hydrogel layer substrate, which was recorded as the first carbon layer.

[0040] (2) Selecting a gold target, using a magnetron sputtering method, sputtering gold nanoparticles on the carbon layer obtained in step (1). The magnetron sputtering process parameters are: RF sputtering power 200 W, time 6 s, Ar gas pressure 20 mTorr, Ar gas flow rate 30 sccm, to obtain a composite layer with gold nanoparticles uniformly distributed on the surface.

[0041] (3) Selecting a carbon target, using a magnetron sputtering method, sputtering a carbon layer on the composite layer obtained in step (2), the magnetron sputtering process parameters are: RF sputtering power 200W, time 2600s, Ar gas pressure 20mTorr, Ar gas flow rate 30sccm, the carbon layer is recorded as the second carbon layer, and a composite film is obtained. Part of the first carbon layer and the second carbon layer in the composite film form sp 2 bonding, the sp 2 The bonding maintains a uniform distribution of gold nanoparticles between the first carbon layer and the second carbon layer, that is, before high temperature and high pressure treatment, the first carbon layer and the second carbon layer in the composite film completely wrap the gold nanoparticles, and there is no gap between the first carbon layer and the second carbon layer in the composite film.

[0042] (4) The composite film obtained in step (3) is dissolved in deionized water to remove the polyvinyl alcohol hydrogel layer, thereby obtaining a film having a sandwich structure consisting of a first carbon layer, gold nanoparticles, and a second carbon layer, wherein the total thickness of the film is 60 nm.

[0043] (5) Ten layers of the film obtained in step (4) were stacked, dried naturally, and then cut into square blocks with a side length of 90 μm; then placed in a diamond anvil press, with a layer of sodium chloride laid on the upper and lower sides of the pressure chamber as a thermal insulation layer, pressurized to 30 GPa, laser heated to 1700 ° C and maintained for 2 minutes; finally, the pressure was released to atmospheric pressure, and the diamond inclusions were removed.

[0044] The diamond inclusions obtained in step (5) were subjected to transmission electron microscopy analysis, and the results showed that the gold nanoparticles were evenly distributed in the nanocrystalline diamonds, and the (111) interplanar spacing of the gold nanoparticles encapsulated by diamonds was reduced relative to the initial state, indicating that they were in a high-pressure state.

[0045] Example 2

[0046] A method for preparing a diamond high-pressure inclusion comprises the following steps: (1) A carbon target was selected and magnetron sputtering was used. The magnetron sputtering process parameters were as follows: RF sputtering power 200 W, time 3900 s, Ar pressure 20 mTorr, Ar gas flow rate 30 sccm, and a carbon layer with a thickness of 30 nm was sputtered on the polyvinyl alcohol hydrogel layer substrate, which was recorded as the first carbon layer.

[0047] (2) Selecting a gold target, using a magnetron sputtering method, sputtering gold nanoparticles on the carbon layer obtained in step (1). The magnetron sputtering process parameters are: RF sputtering power 200 W, time 9 s, Ar gas pressure 20 mTorr, Ar gas flow rate 30 sccm, to obtain a composite layer with gold nanoparticles uniformly distributed on the surface.

[0048] (3) Select a carbon target and use a magnetron sputtering method to sputter a carbon layer on the composite layer obtained in step (2). The magnetron sputtering process parameters are: RF sputtering power 200W, time 3900s, Ar gas pressure 20mTorr, Ar gas flow rate 30sccm. This carbon layer is recorded as the second carbon layer to obtain a composite film. Its cross-sectional transmission electron microscopy photos and planar transmission electron microscopy photos are shown in Figure 2. Figure 2 and 3 As shown, the electron energy loss spectrum of the carbon layer in the film is as follows Figure 4 As shown, it can be seen that the first carbon layer and the second carbon layer in the composite film form sp 2 bonding, the sp 2The bonding maintains a uniform distribution of gold nanoparticles between the first carbon layer and the second carbon layer, that is, before high temperature and high pressure treatment, the first carbon layer and the second carbon layer in the composite film completely wrap the gold nanoparticles, and there is no gap between the first carbon layer and the second carbon layer in the composite film.

[0049] (4) The composite film obtained in step (3) is dissolved in deionized water to remove the polyvinyl alcohol hydrogel layer, thereby obtaining a film having a sandwich structure consisting of a first carbon layer, gold nanoparticles, and a second carbon layer, wherein the total thickness of the film is 90 nm.

[0050] (5) 20 layers of the film obtained in step (4) were stacked, dried naturally, and then cut into square blocks with a side length of 90 μm; then loaded into a diamond anvil press, the upper and lower pressure chambers were filled with argon as a thermal insulation layer, pressurized to 30 GPa, heated to 1700 ° C and maintained for 2 minutes; finally, the pressure was released to atmospheric pressure and the diamond inclusions were taken out.

[0051] The diamond inclusions obtained in step (5) were analyzed by transmission electron microscopy. Figure 5 As shown, gold nanoparticles are evenly distributed in nanocrystalline diamonds. Figure 2 and Figure 3 In contrast, the distribution and size of the gold nanoparticles encapsulated by diamond are preserved, and the average (111) interplanar spacing of the gold nanoparticles is Indicates that it is under high pressure.

[0052] Example 3

[0053] A method for preparing a diamond high-pressure inclusion comprises the following steps: (1) A carbon target was selected and magnetron sputtering was used. The magnetron sputtering process parameters were as follows: RF sputtering power 200 W, time 3900 s, Ar pressure 20 mTorr, Ar gas flow rate 30 sccm, and a carbon layer with a thickness of 30 nm was sputtered on the polyvinyl alcohol hydrogel layer substrate, which was recorded as the first carbon layer.

[0054] (2) Selecting a gold target, using a magnetron sputtering method, sputtering gold nanoparticles on the carbon layer obtained in step (1). The magnetron sputtering process parameters are: RF sputtering power 200 W, time 9 s, Ar gas pressure 20 mTorr, Ar gas flow rate 30 sccm, to obtain a composite layer with gold nanoparticles uniformly distributed on the surface.

[0055] (3) Select a carbon target and use magnetron sputtering to sputter a carbon layer on the composite layer obtained in step (2). The magnetron sputtering process parameters are: RF sputtering power 200W, time 3900s, Ar pressure 20mTorr, Ar flow rate 30sccm. This carbon layer is recorded as the second carbon layer to obtain a composite film. Part of the first carbon layer and the second carbon layer in the composite film form sp2 bonding, the sp 2 The bonding maintains a uniform distribution of gold nanoparticles between the first carbon layer and the second carbon layer, that is, before high temperature and high pressure treatment, the first carbon layer and the second carbon layer in the composite film completely wrap the gold nanoparticles, and there is no gap between the first carbon layer and the second carbon layer in the composite film.

[0056] (4) The composite film obtained in step (3) is dissolved in deionized water to remove the polyvinyl alcohol hydrogel layer, thereby obtaining a film having a sandwich structure consisting of a first carbon layer, gold nanoparticles, and a second carbon layer, wherein the total thickness of the film is 90 nm.

[0057] (5) 20 layers of the film obtained in step (4) were stacked, dried naturally, and then cut into square blocks with a side length of 60 μm; then loaded into a diamond anvil press, and argon gas was filled in the upper and lower pressure chambers as a thermal insulation layer. After pressurizing to 40 GPa, it was heated to 1900 ° C and maintained for 2 minutes; finally, the pressure was released to atmospheric pressure, and the diamond inclusions were taken out.

[0058] The diamond inclusions obtained in step (5) were analyzed by transmission electron microscopy. Figure 6 As shown, gold nanoparticles are evenly distributed in nanocrystalline diamonds, and the average (111) interplanar spacing of gold nanoparticles encapsulated by diamonds is This indicates that the diamond is in a high-pressure state, and its pressure is higher than that of the gold nanoparticles in Example 2. This indicates that in the high-temperature and high-pressure process, the structure (phase) and pressure value of the diamond high-pressure inclusion can be controlled by changing the pressure and temperature parameters.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for preparing a diamond high-pressure inclusion, wherein the diamond high-pressure inclusion comprises a diamond high-pressure chamber and a solid high-pressure material located within the diamond high-pressure chamber; the high-pressure material is a material at a pressure greater than 1 atmosphere; and wherein: The preparation method comprises: using a solid target material and two or more layers of thin film carbon material as main raw materials and subjecting them to high temperature and high pressure treatment; enclosing the target material with a certain spatial distribution and / or a certain size between two adjacent layers of the thin film carbon material; The high temperature and high pressure treatment transforms the carbon material into the diamond high pressure chamber enclosing the high pressure material.

2. The method for preparing diamond high-pressure inclusions according to claim 1, characterized in that: Before the high temperature and high pressure treatment, the target material is completely wrapped by the thin film carbon material, so that there is no gap between the two adjacent wrapped layers of thin film carbon material.

3. The method for preparing a diamond high-pressure inclusion according to claim 1 or 2, characterized in that: The preparation of the raw material includes: first setting the target material on the carbon material in the form of a thin film, and then setting the carbon material in the form of a thin film; the carbon material in the form of a thin film is formed by a thin film preparation process, and the thin film preparation process includes one or more of physical vapor deposition, chemical vapor deposition, atomic layer deposition, and wet chemical methods.

4. The method for preparing a diamond high-pressure inclusion according to any one of claims 1 to 3, characterized in that: The total thickness of the composite film composed of two adjacent layers of the carbon material in the form of a thin film and the target material therebetween is denoted as D, and the value range of D is 10 nm to 50 μm; The thickness of a layer of the thin film carbon material is denoted as d, and d is greater than or equal to 30% of D.

5. The diamond high-pressure inclusion according to any one of claims 1 to 4, characterized in that: The target material comprises a morphology of particles, rods, flakes, or a combination of two or more thereof; Preferably, the target material comprises nanoparticles in a monodisperse state.

6. The method for preparing a diamond high-pressure inclusion according to any one of claims 1 to 5, characterized in that: The high temperature and high pressure treatment comprises: treating the raw material under the conditions of 15 to 100 GPa and 1200 to 2500° C.; Preferably, the raw material is treated under conditions of 15 to 100 GPa and 1200 to 2500° C. for 1 to 20 minutes.

7. The method for preparing a diamond high-pressure inclusion according to any one of claims 1 to 6, characterized in that: The high temperature and high pressure treatment is performed using a diamond anvil cell or a large cavity press.

8. The method for preparing a diamond high-pressure inclusion according to any one of claims 1 to 7, characterized in that: include: A thin film preparation process is used to form a first layer of carbon material in the form of a thin film; forming a target material on the first layer of thin film-shaped carbon material to obtain a composite layer; forming a second layer of carbon material in the form of a thin film on the composite layer using a thin film preparation process to obtain a composite film; After stacking more than one layer of composite films, high temperature and high pressure treatment is performed and the pressure is released to obtain the diamond high pressure inclusion.

9. A diamond high-pressure inclusion, characterized in that: The diamond high-pressure inclusion is prepared by the preparation method of any one of claims 1 to 8.

10. The diamond high-pressure inclusion according to claim 9, characterized in that: The high-pressure material includes nanoparticles in a monodisperse state.

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