CN108213456B - Preparation method of cubic nanometer copper powder - Google Patents
Preparation method of cubic nanometer copper powder Download PDFInfo
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- CN108213456B CN108213456B CN201711297170.0A CN201711297170A CN108213456B CN 108213456 B CN108213456 B CN 108213456B CN 201711297170 A CN201711297170 A CN 201711297170A CN 108213456 B CN108213456 B CN 108213456B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
- B22F1/054—Nanosized particles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
- B22F1/054—Nanosized particles
- B22F1/0553—Complex form nanoparticles, e.g. prism, pyramid, octahedron
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
Abstract
The invention belongs to a preparation method of cubic nanometer copper powder in the technical field of nanometer copper powder preparation. The method comprises the steps of taking copper salt as a raw material, taking deionized water or absolute ethyl alcohol as a solvent, adding stearic acid or oleic acid into a solution as a protective agent and a dispersing agent, adding a high-concentration alkali solution to enable the solution and the copper salt to generate a copper hydroxide colloid, and adjusting the pH value of the solution through the alkali solution to enable the solution to be alkaline; then, hydrazine hydrate is dropwise added into the prepared copper hydroxide colloid as a reducing agent, the mixture is heated at the constant temperature of 20-90 ℃, and the reaction lasts for 10-300min, so that the cubic nanometer copper powder can be obtained. The copper powder in the nano copper powder prepared by the method is cubic, the particle size distribution is uniform, the average side length is 100nm, the yield is over 90 percent, the dispersion degree is extremely high, the phenomenon of particle agglomeration is avoided, and the copper powder can be dispersed in water and a weak solvent; simple process, low heating temperature and low energy consumption, and is suitable for mass production.
Description
Technical Field
The invention belongs to the technical field of preparation of nano-copper powder, and particularly relates to a preparation method of cubic nano-copper powder.
Background
By copper nanopowder is meant copper powder in which the constituent phases or grains are less than 100nm in size in each dimension. Since the size of the composition phase or crystal grain is close to the size of a molecule, the nano copper powder has size effect, quantum tunnel effect, surface effect, volume effect and the like similar to other nano metal powder, thereby showing many special properties completely different from bulk metal copper, such as reduced melting point, increased surface energy, improved catalytic activity, greatly increased elongation rate, reduced conductivity and the like. Copper nanoparticles are widely used as coating materials, catalysts, conductive materials, rocket nozzles, advanced solid lubricants, and the like.
The cubic nanometer copper powder has extremely important application in the preparation of novel nanometer composite catalysts, can provide a catalyst matrix, and allows other materials to be attached to the catalyst matrix, so that a composite catalyst with extremely excellent performance can be obtained. Because each surface of the cubic nanometer copper powder is relatively flat, the main advantage of the cubic nanometer copper powder compared with the spherical nanometer copper powder is that whether other materials are attached to the cubic nanometer copper powder or not and the attachment condition are convenient to observe. In addition, the copper powder has high dispersity, can be uniformly dispersed in the soldering paste, and improves the mechanical property and the electrical property of the soldering paste. In a word, the cubic nanometer copper powder has extremely important application in the field of material science.
The preparation method of the nano copper powder is mainly divided into a physical method and a chemical method. Among them, physical methods include physical vapor deposition, high-energy ball milling, and gamma ray methods, and chemical methods include chemical vapor deposition, chemical precipitation, sol-gel method, hydrothermal method, electrolytic method, and liquid-phase reduction method. The existing liquid phase reduction method can be used for preparing the cubic nanometer copper powder, but the preparation method has high heating temperature and complicated operation steps, and the obtained powder has uneven granularity, is not easy to disperse and has lower yield. Therefore, it is necessary to develop a more practical method for preparing cubic copper nanoparticles with uniform particle size and easy dispersion.
Disclosure of Invention
The invention aims to provide a preparation method of cubic nanometer copper powder, which is characterized by comprising the following specific steps:
(1) dissolving a copper salt in deionized water or an absolute ethyl alcohol solvent, adding an acidic dispersing agent, and uniformly stirring by magnetic force to obtain a mixed solution of the copper salt and the dispersing agent;
(2) preparing a high-concentration alkali solution, quickly dripping the high-concentration alkali solution into the mixed solution in the step (1) under the magnetic stirring to generate Cu (OH)2A colloid;
(3) pouring the colloidal solution obtained in the step (2) into a three-neck flask, introducing a protective gas at normal pressure, heating the colloidal solution to a certain temperature, dropwise adding a reducing agent hydrazine hydrate into the colloidal solution, carrying out constant-temperature reaction under magnetic stirring, and obtaining a dispersion liquid of cubic nanometer copper powder after the reaction is finished;
(4) and (4) carrying out centrifugal separation on the cubic copper powder dispersion liquid obtained in the step (3), washing and vacuum drying to obtain cubic nanometer copper powder.
The copper salt in the step (1) is one or more of copper chloride, cuprous chloride, copper sulfate and copper nitrate, and the concentration of the copper salt in the solvent is 0.01-5 mol/L;
in the step (1), the acidic dispersing agent is stearic acid or oleic acid, when the acidic dispersing agent is stearic acid, ethanol is selected as a solvent, and the step (1) is carried out at 50 ℃; when the acidic dispersing agent is oleic acid, deionized water is selected as a solvent, and the step (1) is carried out at normal temperature; wherein the acidic dispersant also acts as a protectant.
The mass ratio of the acidic dispersant to the copper element is (0.1-50): 1.
The magnetic stirring speed in the step (2) and the step (3) is 500-1500 r/min.
The alkali solution in the step (2) is one or more of sodium hydroxide, potassium hydroxide and concentrated ammonia water, the selected solvent is the same as the solvent in the step (1), and the concentration of the alkali solution is 0.5-5 mol/L.
The speed of quickly adding the alkali liquor in the step (2) is 0.5-2L/min, and the pH value of the mixed solution is adjusted to 11-14 so as to quickly form a large amount of Cu (OH) with the size of small to nanometer level2The core of (1).
And (3) introducing a protective gas such as nitrogen or inert gas at normal pressure to prevent the generated nano copper powder from being oxidized by oxygen in the air, wherein the protective gas is stable gas such as nitrogen or inert gas.
The reaction temperature in the step (3) is 20-90 ℃, and the reaction time is 10-300 min.
In the step (3), the hydrazine hydrate is dropwise added to prevent a large amount of heat generated by the reaction and agglomerate original fine cores, wherein the mass ratio of the hydrazine hydrate to the copper element is (5-15): 1.
And (3) selecting anhydrous ethanol and/or deionized water as the detergent in the step (4), and washing for 3-4 times.
The content of the nano copper in the cubic nano copper powder obtained in the step (4) is not less than 95 wt%, and the balance is a dispersing agent on the surface of the nano copper; the side length of the copper nano particles is 50-200nm, and most of the copper nano particles are distributed at 50-100 nm; the cubic nanometer copper powder can be dispersed in water and weak solvent.
The invention has the beneficial effects that:
(1) the copper powder prepared by the method is cubic, has high dispersity, does not have the phenomenon of particle agglomeration, and has important practical value for research and development and industrialization of novel nano powder.
(2) The cubic nanometer copper powder prepared by the method has good oxidation resistance, uniform particle size distribution, average side length of 100nm, yield of more than 90 percent, side length distribution of 50-200nm and most of 50-100nm, and can be dispersed in water and weak solvent.
(3) The preparation method provided by the invention has the advantages of simple process, low heating temperature, low energy consumption, economy and high efficiency, and is suitable for mass production.
Drawings
FIG. 1 is a Transmission Electron Microscope (TEM) image of the cubic nanopattern powder prepared in example 1.
Detailed Description
The invention provides a preparation method of cubic nanometer copper powder, which is further explained by combining the attached drawings and an embodiment.
Fig. 1 is a Transmission Electron Microscope (TEM) image of the cubic copper nanoparticies prepared in example 1, from which it can be seen that the surfaces of the cubic copper nanoparticies are relatively smooth and the cubes are well-defined.
Example 1
(1) 5g of stearic acid was added to 250mL of 0.04mol/L CuCl at 50 deg.C2In the ethanol solution, the mixture is stirred evenly by magnetic force to obtain CuCl2And stearic acid;
(2) preparing 2mol/L NaOH ethanol solution, rapidly adding the NaOH ethanol solution into the solution obtained in the step (1) at the speed of 0.7L/min under the condition of magnetic stirring at 800r/min, adjusting the pH of the solution to 12, and preparing Cu (OH))2A colloid;
(3) pouring the colloidal solution obtained in the step (2) into a three-neck flask, and introducing N under normal pressure2Heating the colloidal solution with protective gas while stirring, heating to the external temperature of 75 ℃, dropwise adding 6.4g of hydrazine hydrate into the three-neck flask, stirring for 120min at constant temperature, and obtaining a cubic nano-copper dispersion liquid after the reaction is finished;
(4) and (4) carrying out centrifugal separation on the cubic copper powder dispersion liquid obtained in the step (3) to obtain copper colloid, washing the copper colloid with an absolute ethyl alcohol solution for three times, washing the copper colloid with deionized water for one time, and carrying out vacuum drying to obtain cubic nanometer copper powder with the side length of 60-120 nm.
Example 2
(1) At room temperature, 3g of oleic acid was added to 100mL of 0.1mol/L CuCl2In deionized water solution, stirring evenly by magnetic force to obtain CuCl2And oleic acid;
(2) preparing 4mol/L NaOH aqueous solution, rapidly adding the NaOH aqueous solution into the solution obtained in the step (1) at the speed of 1.2L/min under the condition of magnetic stirring at 700r/min to prepare Cu (OH)2A colloid;
(3) pouring the colloidal solution obtained in the step (2) into a three-neck flask, introducing argon gas as a protective gas, heating the colloidal solution while stirring, heating to an external temperature of 80 ℃, dropwise adding 4g of hydrazine hydrate into the three-neck flask, stirring at a constant temperature for 180min, and obtaining a nano-copper dispersion after the reaction is finished;
(4) and (4) carrying out centrifugal separation on the copper powder dispersion liquid obtained in the step (3) to obtain copper colloid, washing the copper colloid three times by using deionized water, and carrying out vacuum drying to obtain the cubic nanometer copper powder with the side length of 80-130 nm.
Example 3
(1) 3g of stearic acid was added to 200mL of 0.05mol/L CuSO at 50 deg.C4In ethanol solution to obtain CuSO4And stearic acid;
(2) preparing a KOH ethanol solution with the concentration of 1.5mol/L, rapidly adding the KOH ethanol solution into the solution obtained in the step (1) at the speed of 1.9L/min under the condition of magnetic stirring at 1000r/min, adjusting the pH value of the solution to 12, and preparing Cu (OH)2A colloid;
(3) pouring the colloidal solution obtained in the step (2) into a three-neck flask, introducing argon gas as a protective gas, heating the colloidal solution while stirring, heating to an external temperature of 75 ℃, dropwise adding 5g of hydrazine hydrate into the three-neck flask, stirring at a constant temperature for 300min, and obtaining a nano-copper dispersion after the reaction is finished;
(4) and (4) carrying out centrifugal separation on the copper powder dispersion liquid obtained in the step (3) to obtain copper colloid, washing the copper colloid with an absolute ethyl alcohol solution for three times, washing the copper colloid with deionized water for one time, and carrying out vacuum drying to obtain the cubic nanometer copper powder with side length distribution of 60-150 nm.
Claims (7)
1. The preparation method of the cubic nanometer copper powder is characterized by comprising the following specific steps of:
(1) dissolving a copper salt in deionized water or an absolute ethyl alcohol solvent, adding an acidic dispersing agent, and uniformly stirring by magnetic force to obtain a mixed solution of the copper salt and the dispersing agent; in the step (1), the acidic dispersing agent is stearic acid or oleic acid, when the acidic dispersing agent is stearic acid, ethanol is selected as a solvent, and the step (1) is carried out at 50 ℃; when the acidic dispersing agent is oleic acid, deionized water is selected as a solvent, and the step (1) is carried out at normal temperature;
(2) preparing a high-concentration alkali solution with the concentration of 0.5-5 mol/L, and quickly dropwise adding the high-concentration alkali solution into the mixed solution obtained in the step (1) to generate Cu (OH)2A colloid; the dropping speed of the alkali liquor is 0.5-2L/min, and the pH value of the mixed solution is adjusted to 11-14;
(3) pouring the colloidal solution obtained in the step (2) into a three-neck flask, introducing a protective gas under normal pressure, heating and stirring, dropwise adding a reducing agent hydrazine hydrate into the colloidal solution, reacting at constant temperature, and obtaining a dispersion liquid of cubic nanometer copper powder after the reaction is finished;
(4) carrying out centrifugal separation, washing and vacuum drying on the cubic copper powder dispersion liquid obtained in the step (3) to obtain cubic nanometer copper powder with side length distribution of 50-200 nm;
the content of the nano-copper in the cubic nano-copper powder obtained in the step (4) is not less than 95 wt%, and the balance is a dispersing agent on the surface of the nano-copper.
2. The method for preparing cubic nanometer copper powder as claimed in claim 1, wherein the copper salt in the step (1) is one or more of copper chloride, cuprous chloride, copper sulfate and copper nitrate, and the concentration of the copper salt in the solvent is 0.01 mol/L-5 mol/L.
3. The method for preparing cubic copper nanopowder according to claim 1, wherein the mass ratio of the acidic dispersant to the copper element is (0.1-50): 1.
4. The method for preparing cubic nanometer copper powder as claimed in claim 1, wherein the alkali solution in the step (2) is one or more of sodium hydroxide, potassium hydroxide and concentrated ammonia water.
5. The method for preparing cubic nanometer copper powder as claimed in claim 1, wherein the reaction temperature in the step (3) is 20-90 ℃ and the reaction time is 10-300 min.
6. The method for preparing cubic nanometer copper powder as claimed in claim 1, wherein the mass ratio of hydrazine hydrate to copper element in the step (3) is (5-15): 1.
7. The method for preparing cubic nanometer copper powder as claimed in claim 1, wherein the magnetic stirring speed in step (1) is 500-1500 r/min; and (4) selecting absolute ethyl alcohol and/or deionized water as the detergent, and washing for 3-4 times.
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| CN108796649A (en) * | 2018-07-17 | 2018-11-13 | 澳洋集团有限公司 | A kind of preparation method of magnetic viscose fibre |
| US11253920B2 (en) * | 2019-07-29 | 2022-02-22 | Honda Motor Co., Ltd. | Method for preparation of copper nanocubes utilizing tributylphosphine as a ligand |
| CN113337847B (en) * | 2021-05-11 | 2022-03-04 | 武汉大学 | Preparation method of cubic copper particles with multi-edge structure |
| CN113355149B (en) * | 2021-06-21 | 2022-07-22 | 江苏万标检测有限公司 | Preparation method of anti-wear hydraulic oil |
| CN114346254B (en) * | 2022-01-21 | 2023-08-18 | 重庆科技学院 | Method for preparing nanometer copper powder in eutectic ionic liquid |
| CN114835152A (en) * | 2022-05-14 | 2022-08-02 | 安徽纳洛米特新材料科技股份有限公司 | Method for industrially producing nano cuprous oxide |
| CN114951682B (en) * | 2022-05-27 | 2023-06-27 | 郑州大学 | Method for preparing Cu nano square by crystal face regulation and control and application thereof |
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| CN1861298A (en) * | 2005-05-13 | 2006-11-15 | 中国科学院理化技术研究所 | Method for preparing cube shaped copper particles |
| CN105798320A (en) * | 2014-12-31 | 2016-07-27 | 中国科学院化学研究所 | Method for preparing nanometer copper powder at low temperature |
| CN106853538A (en) * | 2016-12-19 | 2017-06-16 | 北京科技大学 | A kind of quick method for preparing particle diameter and the copper nano-particle of morphology controllable |
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| KR100797484B1 (en) * | 2006-08-29 | 2008-01-23 | 삼성전기주식회사 | Method for manufacturing cubic copper or copper oxide nanoparticles |
| CN102205422A (en) * | 2011-01-17 | 2011-10-05 | 深圳市圣龙特电子有限公司 | Nano copper powder for electronic paste and preparation process |
| CN103464774B (en) * | 2012-06-07 | 2016-02-24 | 荆门市格林美新材料有限公司 | The preparation method of low reunion Anti-Oxidation Copper Nanopowders |
| CN107159900B (en) * | 2017-05-10 | 2019-05-28 | 上海应用技术大学 | A kind of method of copper nanocube controllable preparation |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1861298A (en) * | 2005-05-13 | 2006-11-15 | 中国科学院理化技术研究所 | Method for preparing cube shaped copper particles |
| CN105798320A (en) * | 2014-12-31 | 2016-07-27 | 中国科学院化学研究所 | Method for preparing nanometer copper powder at low temperature |
| CN106853538A (en) * | 2016-12-19 | 2017-06-16 | 北京科技大学 | A kind of quick method for preparing particle diameter and the copper nano-particle of morphology controllable |
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Address after: 100088, 2, Xinjie street, Xicheng District, Beijing Patentee after: Youyan Technology Group Co.,Ltd. Patentee after: NATIONAL CENTER FOR NANOSCIENCE AND TECHNOLOGY Patentee after: GRIPM ADVANCED MATERIALS Co.,Ltd. Address before: 100088, 2, Xinjie street, Xicheng District, Beijing Patentee before: GENERAL Research Institute FOR NONFERROUS METALS Patentee before: NATIONAL CENTER FOR NANOSCIENCE AND TECHNOLOGY Patentee before: GRIPM ADVANCED MATERIALS Co.,Ltd. Address after: 100088, 2, Xinjie street, Xicheng District, Beijing Patentee after: China Youyan Technology Group Co.,Ltd. Patentee after: NATIONAL CENTER FOR NANOSCIENCE AND TECHNOLOGY Patentee after: GRIPM ADVANCED MATERIALS Co.,Ltd. Address before: 100088, 2, Xinjie street, Xicheng District, Beijing Patentee before: Youyan Technology Group Co.,Ltd. Patentee before: NATIONAL CENTER FOR NANOSCIENCE AND TECHNOLOGY Patentee before: GRIPM ADVANCED MATERIALS Co.,Ltd. |