Method for synthesizing boron phosphide polycrystalline block by using amorphous boron source and phosphorus source through one-step method

Abstract

The invention is applicable to the technical field of boron phosphide polycrystalline synthesis, and provides a method for synthesizing a boron phosphide polycrystalline block by using an amorphous boron source and a phosphorus source through a one-step method, which comprises the following steps: fully ball-milling and mixing amorphous boron powder and amorphous phosphorus powder; pressing the raw materials into a cylinder; the cylinder is placed in a high-pressure assembly, then the high-pressure assembly is placed in a cavity of a cubic press, and heating is conducted for 60 min under the conditions that the pressure ranges from 2 GPa to 5 GPa and the temperature ranges from 950 DEG C to 1350 DEG C. The invention also provides a boron phosphide polycrystalline block and an application of the boron phosphide polycrystalline block in preparation of a high-heat-dissipation device. The boron phosphide polycrystalline ceramic sintered body is synthesized at high temperature and high pressure through a one-step method by adopting a domestic cubic press, the cost is low, the time is short, the process is simple, the pressure is relatively low, and the yield is high; the synthesized sample has the characteristics of simple process, high hardness, high heat conductivity and the like, has very wide application potential, can be used for superhard inorganic compounds, refractory materials, high heat dissipation devices or ships and the like, and can prevent ship bodies and parts from being corroded by seawater and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of boron phosphide polycrystal synthesis, and in particular relates to a method for synthesizing a boron phosphide polycrystal block by using an amorphous boron source and a phosphorus source in a one-step process. Background Art

[0002] With the continuous development of science and technology and the continuous progress of urbanization, the demand for high-performance materials is also growing. Boron phosphide materials have begun to attract people's attention because of their unique properties. Boron phosphide materials have a hardness of 32Gpa under a load of 100g; its density is 2.90g / cm 3 It is a material with relatively high density; it has good thermal conductivity and thermal stability; in terms of optics, its film has good light transmittance in a wide band and good corrosion resistance; it has good chemical stability and generally does not react with concentrated acid and alkaline solutions.

[0003] Although boron phosphide has good performance, it is difficult to synthesize it under normal pressure. However, it is relatively easy to synthesize a single pure phase of boron phosphide under high pressure. Generally speaking, the conventional method for preparing boron phosphide materials is as follows:

[0004] Although the method of thermal decomposition of PCl3·BCl3 can produce the target material, the process is relatively complicated and the product quality is unstable;

[0005] The method of boron reacting with zinc phosphide or phosphine. Zinc phosphide and phosphine are relatively difficult to obtain and the cost is relatively high. At the same time, there may be the problem of generating dangerous gases during the reaction process, which poses certain safety risks.

[0006] The method of using crystalline boron and elemental phosphorus for synthesis requires relatively high conditions, higher pressure and temperature to synthesize the target product, and usually requires metallic nickel as a catalyst, and cannot synthesize polycrystalline;

[0007] The chemical vapor deposition method requires placing a silicon substrate with a catalyst in a sealed tubular furnace filled with inert gas protection, then evacuating the furnace, raising the temperature to a certain level, and then introducing boron source and phosphorus source precursors to react to obtain the target product. This method has low production efficiency, takes a long time and costs a lot, and has potential hazards from reaction sources and exhaust gases, among other issues.

[0008] The above conventional methods are difficult to obtain boron phosphide polycrystalline ceramic sintered bodies, and the current preparation methods of boron phosphide have many problems, or the performance of the samples prepared is not ideal, and there is also a lot of room for improvement in application. Therefore, it is of great practical significance to develop a new preparation method of boron phosphide materials and expand their application fields. Summary of the invention

[0009] The purpose of the embodiments of the present invention is to provide a method for synthesizing a polycrystalline bulk of boron phosphide using an amorphous boron source and a phosphorus source in a one-step process, aiming to solve the problems raised in the above-mentioned background technology.

[0010] The embodiment of the present invention is implemented as follows: a method for synthesizing a polycrystalline boron phosphide block by a one-step method using an amorphous boron source and a phosphorus source, comprising the following steps:

[0011] (1) fully mixing amorphous boron powder and amorphous phosphorus powder by ball milling;

[0012] (2) Pressing the raw material into a cylinder;

[0013] (3) The cylinder is placed in a high-pressure assembly, and the high-pressure assembly is then placed in the cavity of a six-sided press, and heated for 60 minutes at a pressure of 2-5 GPa and a temperature of 950-1350°C.

[0014] Preferably, in step (1), the molar ratio of the amorphous boron powder to the amorphous phosphorus powder is 1:1.

[0015] Preferably, in step (1), the purity of the amorphous boron powder is 90%.

[0016] Preferably, in step (1), the purity of the amorphous boron powder is 99%.

[0017] Preferably, in step (1), the purity of the amorphous phosphorus powder is 98.5%.

[0018] Preferably, in step (2), the raw material is pressed into a cylinder under 3 Mpa, with a diameter of 10 mm and a height of 4 mm.

[0019] Another object of an embodiment of the present invention is to provide a boron phosphide polycrystalline block, which is synthesized using the above method.

[0020] Another object of the embodiment of the present invention is to provide an application of the above-mentioned boron phosphide polycrystalline block in the preparation of high heat dissipation devices.

[0021] The embodiment of the present invention provides a method for synthesizing a polycrystalline boron phosphide block in one step using an amorphous boron source and a phosphorus source. The method adopts a domestic six-sided top press machine, uses amorphous boron powder (amorphous boron powder) and amorphous phosphorus powder as raw materials, and synthesizes a polycrystalline boron phosphide ceramic sintered body in one step under high temperature and high pressure. The method has the characteristics of low cost, short synthesis time, simple synthesis process, low synthesis pressure, low synthesis temperature, high yield, etc. The synthesized sample has the characteristics of simple process, high hardness, high thermal conductivity, etc., and has broad application potential. It can be used in superhard inorganic compounds, refractory materials, high heat dissipation devices or ships, etc., and can prevent the hull and parts from being corroded by seawater, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a picture of the sample prepared according to Example 1 of the present invention;

[0023] Figure 2 This is a scanning electron microscope image of the sample prepared according to Example 1 of the present invention;

[0024] Figure 3 The X-ray diffraction pattern of the sample prepared in Example 1 of the present invention;

[0025] Figure 4 The X-ray diffraction pattern of the sample prepared in Example 8 of the present invention;

[0026] Figure 5 The X-ray diffraction pattern of the amorphous boron powder with a purity of 90% used in the embodiment of the present invention;

[0027] Figure 6 This is an X-ray diffraction pattern of the amorphous phosphorus powder used in the embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] The embodiment of the present invention uses amorphous boron powder (amorphous boron powder) and amorphous phosphorus powder as raw materials, wherein the purity of the amorphous boron powder is 90% or 99%, and the X-ray diffraction spectrum of the amorphous boron powder (amorphous boron powder) raw material with a purity of 90% is as follows: Figure 5 The amorphous phosphorus powder may be specifically amorphous red phosphorus powder with a purity of 98.5%, and the X-ray diffraction pattern of the amorphous red phosphorus raw material is as shown in Figure 6 shown.

[0030] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0031] Embodiment 1: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0032] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0033] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 4 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0034] Embodiment 2: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0035] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0036] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 4 GPa and a temperature of 1050°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0037] Embodiment 3: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0038] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0039] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 4 GPa and a temperature of 950°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0040] Embodiment 4: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0041] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0042] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 4 GPa and a temperature of 1250°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0043] Embodiment 5: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0044] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then put into a planetary ball mill for mixing, and then the mixed raw materials are put into a grinding tool and pre-pressed into a cylinder at 3Mpa, and then put into a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by talc blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite tightly attached to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide sintered composites, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring.

[0045] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 3 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0046] Embodiment 6: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0047] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0048] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 2 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0049] Embodiment 7: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0050] (1) Amorphous boron powder (amorphous boron powder) with a purity of 99% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0051] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 5 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0052] Embodiment 8: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0053] (1) Amorphous boron powder (amorphous boron powder) with a purity of 90% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0054] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 4 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0055] Embodiment 9: A boron phosphide polycrystalline block, wherein the synthesis method comprises the following steps:

[0056] (1) Amorphous boron powder (amorphous boron powder) with a purity of 90% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0057] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 5 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0058] Embodiment 10: A boron phosphide polycrystalline block, the synthesis method of which comprises the following steps:

[0059] (1) Amorphous boron powder (amorphous boron powder) with a purity of 90% and amorphous red phosphorus with a purity of 98.5% in a molar ratio of 1:1 are taken as initial raw materials, and the selected raw materials are then mixed in a planetary ball mill, and then the mixed raw materials are placed in a grinding tool and pre-pressed into a cylinder at 3Mpa, and then placed in a high-pressure assembly, wherein the outermost layer of the high-pressure assembly is wrapped by pyrophyllite blocks, the center of the outer periphery is a steel cap, and further inside are copper sheets and graphite sheets, and further inside is a sintered cylindrical liner composed of magnesium oxide and aluminum oxide, the inner layer of which has a layer of graphite close to the inner wall, and the two ends of the liner are closed by plugs composed of magnesium oxide and aluminum oxide composite sintering, and the inside is a sample, and the periphery of the sample is protected by molybdenum and an insulating ring;

[0060] (2) The assembled high-pressure assembly is placed in the synthesis cavity of a six-sided top press, heated at a pressure of 2 GPa and a temperature of 1150°C for 60 minutes, and then cooled and depressurized to obtain a boron phosphide polycrystalline ceramic sintered body.

[0061] Performance Testing:

[0062] The sample prepared in Example 1 was analyzed to obtain a real photo as shown in the following figure: Figure 1 As shown, the sample is a small disc with a diameter of 10 mm and a height of 4 mm. The sintered density is 2.85 g / cm 3 The density is close to 98.3%, the conductivity is 4S / m, and its structure is sphalerite structure. The sample prepared in Example 7 is analyzed and the scanning electron microscope image is as follows: Figure 2 As shown, under an electron microscope, it can be seen that the grain size is at the micron level;

[0063] The X-ray diffraction pattern of the sample prepared in Example 8 is as follows: Figure 3 As shown, the X-ray diffraction pattern of the sample prepared in Example 1 is as follows Figure 4 shown.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for synthesizing a polycrystalline boron phosphide block by a one-step method using an amorphous boron source and a phosphorus source, characterized in that: The following steps are involved: (1) fully mixing amorphous boron powder and amorphous phosphorus powder by ball milling; (2) Pressing the raw material into a cylinder; (3) The cylinder is placed in a high-pressure assembly, and the high-pressure assembly is then placed in the cavity of a six-sided press, and heated for 60 minutes at a pressure of 2-5 GPa and a temperature of 950-1350°C.

2. The method for synthesizing a polycrystalline boron phosphide block by one-step method using an amorphous boron source and a phosphorus source according to claim 1, characterized in that: In step (1), the molar ratio of the amorphous boron powder to the amorphous phosphorus powder is 1:

1.

3. The method for synthesizing a polycrystalline boron phosphide block by one-step method using an amorphous boron source and a phosphorus source according to claim 1, characterized in that: In step (1), the purity of the amorphous boron powder is 90%.

4. The method for synthesizing a polycrystalline boron phosphide block by one-step method using an amorphous boron source and a phosphorus source according to claim 1, characterized in that: In step (1), the purity of the amorphous boron powder is 99%.

5. The method for synthesizing a polycrystalline boron phosphide block by one-step method using an amorphous boron source and a phosphorus source according to claim 1, characterized in that: In step (1), the purity of the amorphous phosphorus powder is 98.5%.

6. The method for synthesizing a polycrystalline boron phosphide block by one-step method using an amorphous boron source and a phosphorus source according to claim 1, characterized in that: In step (2), the raw material is pressed into a cylinder under the condition of 3 Mpa, with a diameter of 10 mm and a height of 4 mm.

7. A boron phosphide polycrystalline block, characterized in that: It is synthesized by the method described in any one of claims 1 to 5.

8. Use of the boron phosphide polycrystalline block as claimed in claim 7 in preparing high heat dissipation devices.

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