Coralline copper oxide powder, copper powder and preparation method

Abstract

The invention provides a preparation method of coralline copper oxide powder, a preparation method of coralline copper powder, the coralline copper oxide powder and the coralline copper powder, and relates to the technical field of powder materials. The preparation method of the coralline copper oxide powder comprises the following steps: preparing a copper salt aqueous solution and a precipitant aqueous solution; converting the copper salt aqueous solution into copper salt aerosol, converting the precipitant aqueous solution into precipitant aerosol, and mixing the copper salt aerosol and the precipitant aerosol for gas-liquid phase reaction to obtain a suspension containing a copper compound; carrying out homogeneous hydrothermal reaction on the suspension to obtain a reacted solid substance so as to obtain copper precursor powder; and roasting the copper precursor powder to obtain the coralline copper oxide powder. The preparation cost of the coralline copper oxide powder and the copper powder can be reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of powder materials, and in particular to a method for preparing coral-like copper oxide powder, a method for preparing coral-like copper powder, coral-like copper oxide powder and coral-like copper powder. Background Art

[0002] Ultrafine copper oxide is a brown-black metal oxide powder, soluble in dilute acid, insoluble in water and ethanol. It has the characteristics of large specific surface area, high chemical activity, high electron mobility, high thermal conductivity, strong adsorption capacity, strong selectivity, and special electrical, optical, catalytic and other properties. It is widely used in catalytic reactions such as oxidation, reduction, and hydrogenation, and is suitable for lithium-ion batteries, energetic materials, gas sensors, printing and dyeing, glass, ceramics, and medicine. Ultrafine copper powder is a purple-brown or brown powder, mostly used in the production of microelectronic devices and the manufacture of multilayer ceramic capacitor terminals. It can also be used as a catalyst in the reaction process of carbon dioxide and hydrogen to synthesize methanol, as well as petroleum lubricants and the pharmaceutical, electroplating, and coating industries.

[0003] Compared with ordinary coarse particles, ultrafine powders have completely different physical and chemical properties, including small size effect, surface effect, quantum size effect and macroscopic quantum tunneling effect, which makes them exhibit excellent conductivity, magnetism and high catalytic activity.

[0004] Currently, the preparation of copper oxide powder and copper powder generally has the problem of high cost.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] The purpose of the present disclosure is to provide a method for preparing coral-like copper oxide powder, a method for preparing coral-like copper powder, coral-like copper oxide powder and coral-like copper powder, thereby overcoming the problem of high preparation cost of copper oxide powder and copper powder at least to a certain extent.

[0007] According to a first aspect of the present disclosure, a method for preparing coral-like copper oxide powder is provided, comprising: preparing a copper salt aqueous solution and a precipitant aqueous solution; converting the copper salt aqueous solution into a copper salt aerosol, converting the precipitant aqueous solution into a precipitant aerosol, and obtaining a suspension containing copper compounds after the copper salt aerosol and the precipitant aerosol are mixed and subjected to a gas-liquid phase reaction; subjecting the suspension to a homogeneous hydrothermal reaction to obtain a solid substance after the reaction to obtain a copper precursor powder; and calcining the copper precursor powder to obtain the coral-like copper oxide powder.

[0008] Optionally, the copper salt in the copper salt aqueous solution is copper sulfate or copper chloride, and the copper ion concentration in the copper salt aqueous solution is 0.5 mol / L to 1.5 mol / L; the precipitant in the precipitant aqueous solution is sodium carbonate, sodium hydroxide or a mixture of sodium carbonate and sodium hydroxide, and the concentration of the precipitant in the precipitant aqueous solution is 1 mol / L to 3 mol / L.

[0009] Optionally, converting the copper salt aqueous solution into a copper salt aerosol comprises: converting the copper salt aqueous solution into a copper salt aerosol using an atomizing device; wherein the liquid inlet amount of the copper salt aqueous solution in the atomizing device is set to 110 mL / h to 350 mL / h, and the air flow rate of the atomizing device is set to 5 L / min to 20 L / min.

[0010] Optionally, performing a homogeneous hydrothermal reaction on the suspension includes: placing the suspension in a sealed reactor, and performing a homogeneous hydrothermal reaction at a temperature of 80° C. to 120° C. for a reaction time of 4 h to 10 h.

[0011] Optionally, obtaining the solid matter after the reaction to obtain the copper precursor powder includes: performing solid-liquid separation on the suspension after the reaction to obtain the solid matter after the reaction; wherein the solid-liquid separation method includes suction filtration or centrifugation; washing the solid matter; drying the washed solid matter to obtain the copper precursor powder; wherein the drying method includes vacuum drying or freeze drying.

[0012] Optionally, the copper precursor powder is calcined to obtain coral-like copper oxide powder, including: heating the temperature to 350°C to 500°C at a heating rate of 5°C / min to 10°C / min, calcining the copper precursor powder, and keeping the temperature for 2h to 4h to obtain coral-like copper oxide powder.

[0013] According to a second aspect of the present disclosure, a method for preparing coral-like copper powder is provided, comprising: preparing coral-like copper oxide powder by adopting any of the above methods for preparing coral-like copper oxide powder; and subjecting the coral-like copper oxide powder to hydrogen reduction treatment to obtain coral-like copper powder.

[0014] Optionally, the coral-like copper oxide powder is subjected to hydrogen reduction treatment to obtain coral-like copper powder, including: heating the temperature to 180°C to 300°C at a heating rate of 5°C / min to 10°C / min, subjecting the coral-like copper oxide powder to hydrogen reduction treatment, and keeping the temperature for 30min to 2h to obtain coral-like copper oxide powder.

[0015] According to a third aspect of the present disclosure, a coral-like copper oxide powder is provided, which is prepared by any of the above-mentioned methods for preparing coral-like copper oxide powder.

[0016] According to a fourth aspect of the present disclosure, a coral-like copper powder is provided, which is prepared by any of the above-mentioned methods for preparing coral-like copper powder.

[0017] In the scheme of the exemplary embodiment of the present disclosure, on the one hand, by configuring aerosol, gas-liquid phase reaction and hydrothermal combined process, nanoparticle self-assembled coral-shaped copper oxide powder and copper powder can be obtained, which is beneficial to the uniformity and dispersibility of grain size and shape, low cost, simple and easy process implementation and easy control of process conditions. On the other hand, the scheme of the present disclosure converts the reactant solution into an aerosol, and then conducts a gas-liquid phase reaction, thereby effectively regulating the dispersibility of the copper precursor powder and avoiding the agglomeration of particles. On the other hand, through the preparation process of the present disclosure, coral-shaped copper oxide powder and copper powder can be obtained. The coral-shaped morphology has a high specific surface area, so that the copper oxide powder has a strong adsorption capacity when used in battery and catalytic scenarios, and also has more contact points and active sites. In addition, it makes it easier for copper powder to form a conductive network in the application, which is beneficial to the transmission of the reactant, and has excellent electrochemical, catalytic activity and stability.

[0018] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0020] Figure 1 The flowchart of the method for preparing coral-like copper oxide powder according to an exemplary embodiment of the present disclosure is schematically shown.

[0021] Figure 2 A flow chart of a method for preparing coral-like copper powder according to an exemplary embodiment of the present disclosure is schematically shown.

[0022] Figure 3 The XRD (X-ray Diffraction) diagram of the copper oxide powder prepared in Example 1 of the present disclosure is schematically shown.

[0023] Figure 4 A high-magnification SEM (Scanning Electron Microscope) image of the copper oxide powder prepared in Example 1 of the present disclosure is schematically shown.

[0024] Figure 5 A low-magnification SEM image of the copper oxide powder prepared in Example 1 of the present disclosure is schematically shown. DETAILED DESCRIPTION

[0025] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be more comprehensive and complete, and the concepts of the example embodiments are fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced while omitting one or more of the specific details, or other methods, processes, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present disclosure.

[0026] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated descriptions will be omitted. The flowcharts shown in the accompanying drawings are only exemplary illustrations and do not necessarily include all the steps. For example, some steps can also be decomposed, while some steps can be combined or partially combined, so the actual execution order may change according to the actual situation.

[0027] For the preparation of copper oxide powder and copper powder, in some schemes, for example, sol-gel method, microemulsion method, hydrothermal method, chemical precipitation method, template method, electrochemical synthesis method and spray pyrolysis method can be used. Liquid phase chemical synthesis means is an effective method for preparing various metal oxide ultrafine powders. However, some liquid phase precipitation methods are difficult to be effectively controlled in terms of material transport and growth, resulting in the need to add surfactants or add more control means to achieve effective regulation of the morphology and scale of particles. At the same time, what copper oxide and copper ultrafine powders need more in the fields of catalysis and electrochemistry is ultrafine particles with high specific surface area and uniform morphology. Therefore, it is necessary to control the transport, nucleation and growth of materials in the preparation process with low cost, low energy consumption and low pollution to achieve a controllable preparation scheme for copper oxide and copper ultrafine powders with high specific surface area.

[0028] In view of this, the present disclosure provides a new method for preparing copper oxide powder and copper powder.

[0029] Figure 1 The flowchart of the method for preparing coral-like copper oxide powder according to an exemplary embodiment of the present disclosure is schematically shown. Figure 1 The method for preparing the coral-like copper oxide powder according to the embodiment of the present disclosure may include the following steps:

[0030] S12. Prepare a copper salt aqueous solution and a precipitant aqueous solution.

[0031] In an exemplary embodiment of the present disclosure, on one hand, a copper salt and deionized water may be used to prepare a copper salt aqueous solution. On the other hand, a precipitant and deionized water may be used to prepare a precipitant aqueous solution.

[0032] Specifically, the copper salt in the copper salt aqueous solution may be copper sulfate or copper chloride, and the copper ion concentration in the copper salt aqueous solution is, for example, 0.5 mol / L to 1.5 mol / L. The precipitant in the precipitant aqueous solution may be sodium carbonate, sodium hydroxide, or a mixture of sodium carbonate and sodium hydroxide, and the concentration of the precipitant in the precipitant aqueous solution is, for example, 1 mol / L to 3 mol / L.

[0033] S14. Converting the copper salt aqueous solution into copper salt aerosol, converting the precipitant aqueous solution into precipitant aerosol, and after the copper salt aerosol and the precipitant aerosol are mixed to undergo gas-liquid phase reaction, obtaining a suspension containing copper compounds.

[0034] In an exemplary embodiment of the present disclosure, the aqueous solution can be converted into an aerosol by means of a high-pressure airflow. Specifically, the aqueous solution can be converted into an aerosol by an atomizing device (e.g., an atomizing spray gun, etc.). It is understood that the process of converting the copper salt aqueous solution into the copper salt aerosol and the process of converting the precipitant aqueous solution into the precipitant aerosol can be the same.

[0035] Taking the conversion of copper salt aqueous solution into copper salt aerosol as an example, atomization equipment can be used to convert the copper salt aqueous solution into copper salt aerosol. The liquid inlet of the copper salt aqueous solution in the atomization equipment can be set to 110 mL / h to 350 mL / h, and the gas flow rate of the atomization equipment can be set to 5 L / min to 20 L / min.

[0036] Under the action of high-pressure airflow, the copper salt aerosol and the precipitant aerosol are mixed to perform a gas-liquid phase reaction, and the gas-liquid phase reaction can be a reaction in a limited area at room temperature, and the size of the reaction area can be less than or equal to 20 μm, for example, 5 μm to 20 μm. The disclosed embodiment can also refer to the gas-liquid phase reaction as a gas-liquid phase confined micro-area reaction.

[0037] For example, two atomizing devices can be used to convert a copper salt aqueous solution into a copper salt aerosol and a precipitant aqueous solution into a precipitant aerosol respectively, whereby, based on the action of the high-pressure airflow, the two aerosols will undergo a gas-liquid phase reaction in a limited area.

[0038] During the gas-liquid phase reaction, stirring may be continued to obtain a suspension of the copper compound.

[0039] S16. Performing a homogeneous hydrothermal reaction on the suspension to obtain a solid substance after the reaction to obtain a copper precursor powder.

[0040] In an exemplary embodiment of the present disclosure, the suspension obtained in step S14 is placed in a sealed reactor to perform a homogeneous hydrothermal reaction. Specifically, a homogeneous hydrothermal reaction is performed at a temperature of 80° C. to 120° C. for a reaction time of 4 h to 10 h.

[0041] First, the suspension after the reaction can be subjected to solid-liquid separation to obtain the solid matter after the reaction; wherein the solid-liquid separation method includes, for example, suction filtration or centrifugation. Next, the solid matter can be washed. Subsequently, the washed solid matter can be dried to obtain the copper precursor powder; wherein the drying method includes, for example, vacuum drying or freeze drying.

[0042] S18. calcining the copper precursor powder to obtain coral-like copper oxide powder.

[0043] For the calcination process, the temperature can be increased to 350° C. to 500° C. at a heating rate of 5° C. / min to 10° C. / min and kept warm for 2 h to 4 h, thereby obtaining coral-like copper oxide powder from the copper precursor powder.

[0044] Through the above preparation process, the copper oxide powder obtained is a coral-like copper oxide ultrafine powder formed by self-assembly of nanoparticles, and its primary particle size is about 20nm to 30nm. The primary particles self-assemble into nanorods, and then further assemble into coral shapes. The nanorods are about 180nm to 210nm long and about 20nm to 30nm in diameter.

[0045] Based on the above preparation process, further, the embodiment of the present disclosure also provides a method for preparing coral-like copper powder.

[0046] Figure 2 The flowchart of the method for preparing coral-like copper powder according to an exemplary embodiment of the present disclosure is schematically shown. Figure 2 The method for preparing the coral-like copper powder according to the embodiment of the present disclosure may include the following steps:

[0047] S22. Preparation of coral-like copper oxide powder.

[0048] Specifically, the coral-like copper oxide powder can be prepared by the preparation method of steps S12 to S18.

[0049] S24. Performing hydrogen reduction treatment on the coral-like copper oxide powder to obtain coral-like copper powder.

[0050] For the hydrogen reduction treatment process, specifically, the temperature can be raised to 180° C. to 300° C. at a heating rate of 5° C. / min to 10° C. / min, and kept warm for 30 min to 2 h to obtain coral-like copper powder from coral-like copper oxide powder.

[0051] The copper powder obtained in the embodiment of the present disclosure is coral-shaped ultrafine copper powder, and the thickness of the powder laying layer is 5 mm to 20 mm.

[0052] The disclosed solution adopts an atomization method to effectively control the irregular agglomeration phenomenon of the copper precursor during the nucleation and growth process. Without adding any dispersant, by screening the type, concentration and ratio of the precipitant, an oriented growth coral-shaped copper oxide ultrafine powder can be obtained. At the same time, in the further hydrothermal process, the crystallinity of the copper oxide particles is effectively improved.

[0053] In addition, the preparation scheme disclosed in the present invention is conducive to the uniformity of the size and shape of the copper oxide grains and the dispersibility. Before the hydrothermal process, the reactant solution is first converted into an aerosol and a gas-liquid phase reaction is carried out, which can effectively regulate the dispersibility of the copper oxide precursor particles and avoid the agglomeration of the particles. The preparation process disclosed in the present invention has low cost, simple process, low energy consumption, continuous operation and easy control of process conditions.

[0054] In addition, the copper oxide powder and copper powder prepared by the disclosed scheme have high purity, good crystallinity, uniform morphology, and good dispersibility. A series of coral-like copper oxide and copper particles formed by self-assembly of nanoparticles with controllable particle size can be obtained, and the primary particle size is about 20nm to 30nm. The primary particles are self-assembled into nanorods, and then further assembled into corals. The nanorods are about 200nm long and about 20nm to 30nm in diameter. Compared with spherical or flaky copper oxide and copper particles, the coral-like morphology has a higher specific surface area. The coral-like copper oxide particles are used in batteries and catalytic materials with stronger adsorption capacity, and also have more contact points and active sites. Coral-like metallic copper particles are easier to form a conductive network in the application, which is conducive to the transmission of the reactants and has more excellent electrochemical, catalytic activity and stability. The present disclosure effectively obtains coral-like copper oxide and copper particles with high dispersibility, high uniformity, and high specific surface area under the conditions of low cost and low energy consumption.

[0055] The preparation process of the copper oxide powder disclosed in the present invention is described below by way of examples.

[0056] Example 1

[0057] First, copper salt and precipitant are prepared into copper salt aqueous solution and precipitant aqueous solution with concentrations of 1.25 mol / L and 2.94 mol / L respectively, wherein the copper salt is copper sulfate, and the precipitant is a mixture of sodium carbonate and sodium hydroxide, and the addition ratio is 1:2.

[0058] Next, the copper salt aqueous solution and the precipitant aqueous solution were converted into aerosols and subjected to gas-liquid phase reaction, wherein the liquid feed rate was 200 mL / h and the gas flow rate was 15 L / min, thereby obtaining a suspension containing a copper compound.

[0059] Subsequently, the obtained suspension was transferred to a sealed high-pressure reactor for a homogeneous hydrothermal reaction at a temperature of 90°C for a reaction time of 6 hours to obtain a copper precursor suspension. After the reactor was cooled to room temperature, the suspension obtained after the reaction was subjected to solid-liquid separation and washing, and then the filter cake was placed in a vacuum drying oven for drying at a temperature of 80°C to obtain a dark brown copper precursor powder.

[0060] Then, the dried copper precursor powder is calcined at a high temperature with a heating rate of 10°C / min, a reaction temperature of 400°C, and a heat preservation time of 1 hour to obtain coral-like copper oxide powder.

[0061] Figure 3 The XRD pattern of the copper oxide powder prepared in Example 1 of the present disclosure is schematically shown. Figure 3 It can be seen that the copper oxide powder prepared in Example 1 of the present disclosure has the same diffraction peak as the copper oxide in the standard PDF card, has no impurity phase generated, and has good crystallinity.

[0062] Figure 4 The high-magnification SEM image of the copper oxide powder prepared in Example 1 of the present disclosure is schematically shown. Figure 4 As shown, the prepared copper oxide is coral-like copper oxide particles formed by self-assembly of nanoparticles, with a primary particle size of about 20nm to 30nm. The primary particles self-assemble into nanorods, which are then further assembled into coral shapes. The nanorods are about 200nm long and about 20nm to 30nm in diameter.

[0063] Figure 5 The low-magnification SEM image of the copper oxide powder prepared in Example 1 of the present disclosure is schematically shown. Figure 5 As shown, the copper oxide powder prepared in Example 1 of the present disclosure has good particle dispersibility and no obvious agglomeration phenomenon.

[0064] Example 2

[0065] First, copper salt and precipitant are prepared into copper salt aqueous solution and precipitant aqueous solution with concentrations of 0.5 mol / L and 1 mol / L respectively, wherein the copper salt is copper sulfate, and the precipitant is a mixture of sodium carbonate and sodium hydroxide, and the addition ratio is 1:1.

[0066] Next, the copper salt aqueous solution and the precipitant aqueous solution were converted into aerosols and subjected to gas-liquid phase reaction, wherein the liquid feed rate was 110 mL / h and the gas flow rate was 5 L / min, thereby obtaining a suspension containing a copper compound.

[0067] Subsequently, the obtained suspension was transferred to a sealed high-pressure reactor for a homogeneous hydrothermal reaction at a temperature of 80°C for 4 hours to obtain a copper precursor suspension. After the reactor was cooled to room temperature, the suspension obtained after the reaction was subjected to solid-liquid separation and washing, and then the filter cake was placed in a vacuum drying oven for drying at a temperature of 80°C to obtain a dark brown copper precursor powder.

[0068] Then, the dried copper precursor powder is calcined at a high temperature with a heating rate of 5°C / min, a reaction temperature of 350°C, and a heat preservation time of 2h to obtain coral-like copper oxide powder.

[0069] Example 3

[0070] First, copper salt and precipitant are prepared into copper salt aqueous solution and precipitant aqueous solution with concentrations of 1.5 mol / L and 3 mol / L respectively, wherein the copper salt is copper sulfate, and the precipitant is a mixture of sodium carbonate and sodium hydroxide, and the addition ratio is 1:1.

[0071] Next, the copper salt aqueous solution and the precipitant aqueous solution were converted into aerosols and subjected to gas-liquid phase reaction, wherein the liquid feed rate was 350 mL / h and the gas flow rate was 20 L / min, thereby obtaining a suspension containing copper compounds.

[0072] Subsequently, the obtained suspension was transferred to a sealed high-pressure reactor for a homogeneous hydrothermal reaction at a temperature of 120°C for a reaction time of 6 hours to obtain a copper precursor suspension. After the reactor was cooled to room temperature, the suspension obtained after the reaction was subjected to solid-liquid separation and washing, and then the filter cake was placed in a vacuum drying oven for drying at a temperature of 80°C to obtain a dark brown copper precursor powder.

[0073] Then, the dried copper precursor powder is calcined at a high temperature with a heating rate of 5°C / min, a reaction temperature of 500°C, and a heat preservation time of 4 hours to obtain coral-like copper oxide powder.

[0074] Furthermore, the present disclosure also provides a coral-like copper oxide powder, which is prepared by the method of steps S12 to S18 above.

[0075] Furthermore, the present disclosure also provides a coral-like copper powder, which is prepared by the method of step S22 and step S24.

[0076] It should be noted that although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0077] In addition, the above-mentioned figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present disclosure, and are not intended to be limiting. It is easy to understand that the processes shown in the above-mentioned figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0078] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing what is disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and embodiments are to be considered merely as exemplary, and the true scope and spirit of the present disclosure are indicated by the claims.

[0079] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A method for preparing coral-like copper oxide powder, characterized in that: include: preparing a copper salt aqueous solution and a precipitant aqueous solution; The copper salt aqueous solution is converted into a copper salt aerosol, and the precipitant aqueous solution is converted into a precipitant aerosol, and after the copper salt aerosol and the precipitant aerosol are mixed and subjected to gas-liquid phase reaction, a suspension containing a copper compound is obtained; Performing a homogeneous hydrothermal reaction on the suspension to obtain a solid substance after the reaction to obtain a copper precursor powder; The copper precursor powder is calcined to obtain coral-like copper oxide powder.

2. The preparation method according to claim 1, characterized in that: The copper salt in the copper salt aqueous solution is copper sulfate or copper chloride, and the copper ion concentration in the copper salt aqueous solution is 0.5 mol / L to 1.5 mol / L; The precipitant in the precipitant aqueous solution is sodium carbonate, sodium hydroxide or a mixture of sodium carbonate and sodium hydroxide, and the concentration of the precipitant in the precipitant aqueous solution is 1 mol / L to 3 mol / L.

3. The preparation method according to claim 1, characterized in that: Converting the copper salt aqueous solution into a copper salt aerosol comprises: converting the copper salt aqueous solution into a copper salt aerosol by using an atomizing device; Wherein, the liquid inlet amount of the copper salt aqueous solution in the atomizing device is set to 110 mL / h to 350 mL / h, and the gas flow rate of the atomizing device is set to 5 L / min to 20 L / min.

4. The preparation method according to claim 1, characterized in that: The suspension is subjected to a homogeneous hydrothermal reaction comprising: The suspension is placed in a sealed reactor, and a homogeneous hydrothermal reaction is carried out at a temperature of 80° C. to 120° C. for a reaction time of 4 h to 10 h.

5. The preparation method according to claim 1 or 4, characterized in that: The solid material after the reaction is obtained to obtain copper precursor powder, including: Performing solid-liquid separation on the suspension after the reaction to obtain the solid matter after the reaction; wherein the solid-liquid separation method includes suction filtration or centrifugation; washing the solid matter; The washed solid material is dried to obtain copper precursor powder; wherein the drying method includes vacuum drying or freeze drying.

6. The preparation method according to claim 1, characterized in that: The copper precursor powder is calcined to obtain coral-like copper oxide powder, comprising: The copper precursor powder is calcined at a heating rate of 5°C / min to 10°C / min to 350°C to 500°C, and kept warm for 2h to 4h to obtain coral-like copper oxide powder.

7. A method for preparing coral-like copper powder, characterized in that: include: The coral-like copper oxide powder is prepared by the method for preparing the coral-like copper oxide powder according to any one of claims 1 to 6; The coral-like copper oxide powder is subjected to hydrogen reduction treatment to obtain coral-like copper powder.

8. The preparation method according to claim 7, characterized in that: The coral-like copper oxide powder is subjected to hydrogen reduction treatment to obtain coral-like copper powder, comprising: The temperature is raised to 180° C. to 300° C. at a heating rate of 5° C. / min to 10° C. / min, the coral-like copper oxide powder is subjected to hydrogen reduction treatment, and the temperature is kept for 30 minutes to 2 hours to obtain the coral-like copper oxide powder.

9. A coral-like copper oxide powder, characterized in that: The coral-like copper oxide powder is prepared by the preparation method of any one of claims 1 to 6.

10. A coral-like copper powder, characterized in that: The coral-shaped copper powder is prepared by the preparation method of claim 7 or 8.

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