Manufacturing method of nano copper powder

Abstract

The present invention relates to a method for manufacturing nano copper powder capable of efficiently producing high-quality copper powder controlled to nano size. In one embodiment, the manufacturing method can achieve a high reaction rate under mild reaction conditions and can provide nano copper powder having a uniform particle distribution.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing nano-sized copper powder. Background Technology

[0002] Copper powder is an important material widely used in various industrial fields. In particular, due to its excellent electrical and thermal conductivity, it has established itself as an essential material in electronic devices, batteries, conductive pastes, and catalysts. Traditionally, copper has been primarily used in wires, electrical circuits, and electrical contact materials, and thanks to its excellent electrical conductivity, it has played a key role in many industrial sectors.

[0003] Nano copper powder offers advantageous properties for various applications due to its large surface area and excellent physical and chemical reactivity. Copper powder manufactured at the nanoscale exhibits high reactivity and catalytic activity, and tends to show improved conductivity and mechanical properties. Such nano copper powder can play an important role, particularly in conductive pastes for wiring and electronic components in Heterojunction Technology (HJT) solar cells, heat dissipation and bonding pastes for power semiconductors, via-fill pastes for glass substrates for next-generation semiconductors, electromagnetic shielding materials, Energy Storage Systems (ESS), and catalysts. The problem to be solved

[0004] One aspect of the present invention provides a method for manufacturing nano copper powder capable of providing nano-sized copper powder of high quality. means of solving the problem

[0005] One aspect of the present invention is a method for producing nano copper powder, comprising using an aqueous solution comprising a copper precursor; a nonionic surfactant; a phosphite-based compound; and a reducing agent.

[0006] A method for manufacturing the nano copper powder according to one embodiment may comprise the step of reacting a first aqueous solution containing a copper precursor and a nonionic surfactant with a second aqueous solution containing a phosphite-based compound; and the step of mixing and reacting a third aqueous solution containing a reducing agent to produce nano copper powder.

[0007] The above second aqueous solution may further contain a basic substance.

[0008] The above phosphite-based compound may include sodium hypophosphite (NaH2PO2), potassium hypophosphite (KPH2O2), calcium hypophosphite (Ca(H2PO2)2), or ammonium hypophosphite (NH4H2PO2).

[0009] The concentration of copper ions in the above aqueous solution may be 0.01 to 10 M.

[0010] The concentration of the phosphite-based compound in the above aqueous solution may be 0.001 to 1 M.

[0011] The copper ions of the copper precursor and the phosphite compound may be used in a molar ratio of 1:0.005 to 1:0.5.

[0012] The average particle size of the above nano copper powder may be 20 nm to 2,000 nm.

[0013] The above nonionic surfactant may include polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, polysorbate, carboxymethyl cellulose, gelatin, dextran, or xanthan gum.

[0014] The copper precursor may include CuSO4, Cu(NO3)2, or CuCl2.

[0015] The above reaction may be carried out at a temperature of 10 to 90 ℃ for 10 to 100 minutes. Effects of the invention

[0016] According to one embodiment of the manufacturing method, high-quality copper powder controlled to nano-size can be efficiently manufactured.

[0017] A manufacturing method of one embodiment can achieve a fast reaction rate and high yield for the synthesis of nano copper powder under mild reaction conditions. The nano copper powder produced therefrom can have a uniform particle distribution and can be effectively applied in various industrial fields, such as wiring for Heterojunction Technology (HJT) solar cells, conductive paste for electronic components, heat dissipation and bonding paste for power semiconductors, via-fill paste for glass substrates for next-generation semiconductors, electromagnetic shielding materials, energy storage systems (ESS), and catalysts.

[0018] In addition, the manufacturing method of one embodiment is environmentally friendly and can improve productivity because it can produce nano copper powder under mild reaction conditions and in an aqueous environment. Brief explanation of the drawing

[0019] Figure 1 is an FE-SEM analysis image of the nano copper powder prepared in Example 1. Figure 2 is an FE-SEM analysis image of the nano copper powder prepared in Example 2. Figure 3 is an FE-SEM analysis image of the copper powder prepared in Comparative Example 1. Specific details for implementing the invention

[0020] Unless otherwise defined in this specification, all technical and scientific terms have the same meaning as generally understood by those skilled in the art to which the present invention pertains. The terms used in the description herein are merely for the purpose of effectively describing specific embodiments and are not intended to limit the present invention.

[0021] The singular form used in this specification is intended to include the plural form unless specifically indicated otherwise in the context.

[0022] Throughout this specification, the terms “comprising,” “having,” “containing,” or “having” any component mean that, unless specifically stated otherwise, other components are not excluded but may be included, and do not exclude elements, materials, or processes not additionally listed.

[0023] The numerical ranges used herein include lower and upper limits and all values ​​within the range, increments logically derived from the form and width of the defined range, all of which are limited, and all possible combinations of upper and lower limits of the numerical range defined in different forms. Unless otherwise specifically defined in this specification, values ​​outside the numerical range that may occur due to experimental error or rounding are also included in the defined numerical range.

[0024] Unless otherwise specifically defined in this specification, “about” may be considered to be a value within 30%, 25%, 20%, 15%, 10%, or 5% of the specified value.

[0025] The present disclosure will be described in detail below. However, this is merely illustrative and the present disclosure is not limited to the specific embodiments described illustratively.

[0026] One aspect of the present invention provides a method for manufacturing nano copper powder capable of efficiently producing high-quality copper powder controlled to nano size.

[0027] A method for manufacturing nano copper powder according to one embodiment may use an aqueous solution comprising a copper precursor; a nonionic surfactant; a phosphite-based compound; and a reducing agent.

[0028] Specifically, a method for manufacturing nano copper powder according to one embodiment may comprise the step of reacting a first aqueous solution containing a copper precursor and a nonionic surfactant with a second aqueous solution containing a phosphite-based compound; and the step of mixing and reacting a third aqueous solution containing a reducing agent to produce nano copper powder.

[0029] A method for manufacturing nano copper powder according to one embodiment can provide nano-sized copper powder having a uniform particle distribution by satisfying the above composition combination, and can achieve a fast reaction rate and a high yield under mild reaction conditions.

[0030] For example, the above reaction may be carried out at a temperature of 10 to 90 ℃, or 50 to 90 ℃, or 60 to 90 ℃, or 60 to 80 ℃ for 10 to 100 minutes, or 10 to 80 minutes, or 10 to 60 minutes, or 20 to 40 minutes.

[0031] The shape of the nano copper powder produced by the method according to one embodiment is not particularly limited and may be, for example, spherical, elliptical, or angular amorphous. The spherical shape may include not only a perfect sphere in the conventional sense where the surface is substantially equidistant from the center, but also a round shape close to a sphere where no angles are formed. The angular amorphous shape is not particularly limited as long as the particle is angular, and may include, for example, polyhedral shapes selected from tetrahedrons, hexahedrons, octahedrons, etc.; and plate shapes, etc.

[0032] The average particle size of the nano copper powder produced by the method according to one embodiment may be 20 nm to 2,000 nm, or 50 nm to 2,000 nm, 100 nm to 2,000 nm, or 200 nm to 2,000 nm, or 200 nm to 1,000 nm, or 300 nm to 1,000 nm, or 300 nm to 900 nm, or 400 nm to 900 nm, wherein the average particle size may refer to the average value of the longest length of the copper particles. The average particle size of the nano copper powder may be controlled by the type of phosphite compound, the molar ratio of copper ions to the phosphite compound, the type of nonionic surfactant, the molar ratio of copper ions to the nonionic surfactant, or a combination thereof. Here, the average particle size of the nano copper powder may refer to the value obtained by measuring the longest diameter of 100 random copper particles in an image observed by a field emission scanning electron microscope (FE-SEM), averaging the result, and rounding to the nearest ten (unit: nm).

[0033] With respect to the total aqueous solution above, the solid content may be used in an amount of 1 to 50 weight%, or 5 to 50 weight%, or 5 to 30 weight%, or 5 to 20 weight%, but is not limited thereto.

[0034] The above copper precursor may be used without limitation as long as it has high water solubility and can supply copper ions, and non-limiting examples may include Cu(II) precursors such as CuSO4, Cu(NO3)2, or CuCl2.

[0035] The concentration of copper ions in the above total aqueous solution may be 0.01 to 10 M, 0.01 to 5 M, 0.05 to 1 M, or 0.1 to 1 M, or 0.1 to 0.5 M, but is not limited thereto.

[0036] The above phosphite-based compound may include sodium hypophosphite (NaPH2O2), potassium hypophosphite (KPH2O2), calcium hypophosphite (Ca(H2PO2)2), or ammonium hypophosphite (NH4H2PO2).

[0037] The concentration of the phosphite compound in the above total aqueous solution may be 0.001 to 1 M, or 0.005 to 0.5 M, or 0.005 to 0.1 M, or 0.01 to 0.1 M, but is not limited thereto.

[0038] The copper ions of the copper precursor and the phosphite compound may be used in a molar ratio of 1:0.005 to 1:0.5, or 1:0.01 to 1:0.5, or 1:0.05 to 1:0.5, but are not limited thereto.

[0039] The second aqueous solution may further contain a basic substance, and the basic substance may be selected from sodium hydroxide, potassium hydroxide, and sodium carbonate.

[0040] The above phosphite-based compound and base material may be used in a molar ratio of 1:1 to 1:20, or 1:5 to 1:20, or 1:5 to 1:15, but are not limited thereto.

[0041] The above nonionic surfactants may be used without limitation as long as they are commonly used in the relevant technical field, and non-limiting examples may include polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, polysorbate, carboxymethyl cellulose, or gelatin, dextran, and xanthan gum.

[0042] The above nonionic surfactant may be used in an amount of 0.05 to 10 weight%, or 0.05 to 5 weight%, or 0.1 to 5 weight%, or 0.1 to 1 weight% with respect to the total aqueous solution, but is not limited thereto.

[0043] The above reducing agent may be used without limitation as long as it can reduce copper ions, and may be selected from hydrazine, NaBH4, LiBH4, formaldehyde, acetaldehyde, dextrose, glyoxal, and ascorbic acid as a non-limiting example.

[0044] The copper ions of the copper precursor and the reducing agent may be used in a molar ratio of 1:0.5 to 1:7, or 1:1 to 1:7, or 1:2 to 1:5, but are not limited thereto.

[0045] The above-described embodiment will be explained in more detail below through examples. However, the following examples are for illustrative purposes only and do not limit the scope of the claims.

[0046] [Example 1]

[0047] A first aqueous solution was prepared by dissolving 17.16g of Cu(NO3)23H2O and 1g of PVP(K-30) in 300g of distilled water, and a second aqueous solution was prepared by dissolving 1.06g of anhydrous sodium hypophosphite (NaH2PO2) and 5g of NaOH in 50g of distilled water. The first aqueous solution was heated to 50°C, after which the second aqueous solution was added and stirred for 20 minutes. A third aqueous solution was prepared by dissolving 17.2g of ascorbic acid in 50g of distilled water, and this solution was added to the mixture of the first and second aqueous solutions, and the mixture was stirred for 20 minutes while maintaining the temperature at 50°C.

[0048] Afterwards, the reactants were precipitated, washed twice with distilled water and twice with ethanol, and vacuum dried at 50°C to produce nano copper powder.

[0049] The nano copper powder prepared was observed using a field emission scanning electron microscope (FE-SEM). The longest diameters of 100 random copper particles were measured in the FE-SEM images, averaged, and rounded to the nearest ten (unit: nm) to determine the average particle size of the nano copper powder, and the average particle size of the nano copper powder in Example 1 was 500 nm (Fig. 1).

[0050] [Example 2]

[0051] The above Example 1 was carried out in the same manner except that the first aqueous solution was heated to 40°C, and the average particle size of the nano copper powder produced was confirmed to be 900 nm (Fig. 2).

[0052] [Comparative Example 1]

[0053] The above Example 1 was carried out in the same manner except that NaH2PO2 was not used, and the average particle size of the copper powder produced was confirmed to be 10 μm (Fig. 3).

[0054] As described above, the present disclosure has been explained by specific details and limited embodiments, but this is provided only to aid in a more comprehensive understanding of the present disclosure. The present disclosure is not limited to the above embodiments, and various modifications and variations are possible from this description by those skilled in the art to which the present disclosure pertains.

[0055] Accordingly, the present disclosure is not limited to the embodiments described above, and all things equivalent to or having equivalent variations to the claims set forth below, as well as the claims set forth below, shall be considered to be within the scope of the present disclosure.

Claims

Claim 1 A method for producing nano copper powder comprising: a step of reacting a first aqueous solution containing a copper precursor and a nonionic surfactant with a second aqueous solution containing a hypophosphite-based compound; and a step of mixing and reacting a third aqueous solution containing a reducing agent to produce nano copper powder. Claim 2 delete Claim 3 A method for manufacturing nano copper powder according to claim 1, wherein the second aqueous solution further comprises a basic substance. Claim 4 A method for producing nano copper powder according to claim 1, wherein the hypophosphite-based compound comprises sodium hypophosphite (NaH2PO2), potassium hypophosphite (KPH2O2), calcium hypophosphite (Ca(H2PO2)2), or ammonium hypophosphite (NH4H2PO2). Claim 5 A method for manufacturing nano copper powder according to claim 1, wherein the concentration of copper ions in the total aqueous solution is 0.01 to 10 M. Claim 6 A method for producing nano copper powder according to claim 1, wherein the concentration of the phosphite-based compound relative to the total aqueous solution is 0.001 to 1 M. Claim 7 A method for manufacturing nano copper powder according to claim 1, wherein the copper ions of the copper precursor and the phosphite-based compound are used in a molar ratio of 1:0.005 to 1:0.

5. Claim 8 A method for manufacturing nano copper powder according to claim 1, wherein the average particle size of the nano copper powder is 20 nm to 2,000 nm. Claim 9 A method for producing nano copper powder according to claim 1, wherein the nonionic surfactant comprises polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, polysorbate, carboxymethyl cellulose, gelatin, dextran, or xanthan gum. Claim 10 A method for producing nano copper powder according to claim 1, wherein the copper precursor comprises CuSO4, Cu(NO3)2, or CuCl2. Claim 11 A method for manufacturing nano copper powder according to claim 1, wherein the reaction is carried out at a temperature of 10 to 90 ℃ for 10 to 100 minutes.

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