CN-121972655-A - High-oxidation-resistance flaky silver-plated copper powder and preparation method and application thereof

Abstract

The invention discloses high-oxidation-resistance flaky silver-plated copper powder and a preparation method and application thereof, and relates to the technical field of metal powder surface treatment, wherein the preparation method of the flaky silver-plated copper powder comprises the following steps of S1, cleaning the surface of the flaky copper powder; S2, carrying out surface modification on the flaky copper powder subjected to surface cleaning in the step S1 by adopting an organic treating agent, and S3, carrying out silver plating on the surface of the flaky copper powder subjected to surface modification in the step S2 to obtain flaky silver-plated copper powder. The silver layer on the surface of the flaky silver-plated copper powder is compact, has high oxidation resistance and good conductivity, and has excellent comprehensive performance, and the preparation method is simple and easy to control.

Inventors

• JIANG XUEXIN
• YANG JIN

Assignees

• 安徽壹石通材料科技股份有限公司

Dates

Publication Date

20260505

Application Date

20251216

Claims (10)

1. 1. The preparation method of the flake silver-plated copper powder with high oxidation resistance is characterized by comprising the following steps of: S1, cleaning the surface of flaky copper powder; s2, carrying out surface modification on the flaky copper powder subjected to surface cleaning in the step S1 by adopting an organic treating agent; s3, silver plating is carried out on the surface of the flaky copper powder subjected to the surface modification in the step S2, so that flaky silver-plated copper powder is obtained; The organic treating agent is at least one selected from tea polyphenols, chlorogenic acid and p-hydroxy cinnamic acid.
2. 2. The method of claim 1, wherein the copper flake has a median particle size of 10 to 40. Mu.m.
3. 3. The preparation method of the flaky copper powder according to claim 1, wherein the method for surface modification of the flaky copper powder comprises the steps of mixing an organic treating agent with copper powder in a solvent, adding sodium hydroxide to adjust the pH value of the solution to 9-10, stirring at a constant temperature of 50-70 ℃ for 2-4 hours, naturally cooling to room temperature, filtering, and washing with water to obtain the oxidation-resistant flaky copper powder.
4. 4. The method for preparing copper powder according to claim 1 or 3, wherein the organic treating agent is added in an amount of 1.5 to 3% by mass of the copper powder.
5. 5. The preparation method of the silver plating copper powder according to claim 1, wherein the method for plating silver on the surface of the flaky copper powder comprises the steps of uniformly mixing the copper powder subjected to surface modification with a reducing agent, and then dropwise adding a silver-ammonia solution for reaction to obtain the silver-plated copper powder.
6. 6. The method according to claim 5, wherein the reducing agent is at least one of glucose, vitamin C, and sodium potassium tartrate.
7. 7. The preparation method of the silver-ammonia solution according to claim 5, wherein the preparation method comprises the steps of dissolving silver nitrate in water, and then adding a complexing agent for reaction to obtain the silver-ammonia solution; Preferably, the complexing agent is at least one of ethylenediamine, diethylenetriamine and triethylenetetramine; preferably, the silver content of the silver ammonia solution is 3.1-42.9% of the mass of the copper powder, calculated as silver.
8. 8. The high oxidation resistance flake silver-plated copper powder obtained by the preparation method of any one of claims 1 to 7.
9. 9. The high oxidation resistance flaky silver-plated copper powder according to claim 8, wherein the particle size of the flaky silver-plated copper powder is 10-40 μm; Preferably, the silver content of the surface of the flaky silver-plated copper powder is 3.5-30%; preferably, the volume resistivity of the platy silver-plated copper powder is less than 3X 10 -4 ohm cm; Preferably, the oxidation resistance temperature of the flake silver-plated copper powder is higher than 240 ℃.
10. 10. Use of silver-plated copper powder according to claim 8 or 9 in photovoltaic silver paste.

Description

High-oxidation-resistance flaky silver-plated copper powder and preparation method and application thereof Technical Field The invention relates to the technical field of metal powder surface treatment, in particular to high-oxidation-resistance flaky silver-plated copper powder and a preparation method and application thereof. Background With the development of science and technology, the conductive paste becomes an indispensable raw material in modern industrial application. The silver-coated copper powder has the advantages of improving oxidation resistance of the copper powder to a certain extent, having excellent conductivity, greatly reducing cost of the conductive slurry by replacing the silver powder, and being beneficial to popularization and application of the slurry and reducing burden of enterprises. The specific surface area of the flake copper powder is large, the oxidation resistance is worse than that of copper powder with other shapes, and the oxidation resistance can be improved to a certain extent by singly plating silver, but the flake copper powder has a certain gap compared with silver-plated copper powder with other shapes, so that the application of the flake copper powder is limited. The method comprises the steps of ball milling silver balls and copper powder to obtain flaky silver-plated copper powder, carrying out displacement reaction on copper powder and silver salt to obtain flaky silver-plated copper powder by CN103920876B, carrying out direct reduction silver plating on flaky copper powder by CN101032750A, CN101294281B, carrying out acid washing and then reduction silver plating on flaky copper powder by CN109355034A, CN108941539B, CN114101665B, CN102133636B, carrying out stannous chloride treatment and amine activation on flaky copper powder by CN 108817377B and then reduction silver plating, carrying out alcohol washing and acid washing on copper powder by CN119927207A, and then carrying out reduction silver plating. None of the above patents solves the problems of large specific surface area and poor oxidation resistance of the flake copper powder. Therefore, it is very necessary to provide a method for preparing flake silver-plated copper powder with simple and easy control process, high oxidation resistance, good conductivity and compact plating. Disclosure of Invention In order to solve the problem of poor oxidation resistance of flaky silver-plated copper powder in the prior art, the invention provides a preparation method of flaky silver-plated copper powder, which has the advantages of simple and easily controlled process, compact plating layer, good conductivity and strong oxidation resistance. The technical problems to be solved by the invention are realized by adopting the following technical scheme: the first object of the invention is to provide a preparation method of flake silver-plated copper powder with high oxidation resistance, which comprises the following steps: S1, cleaning the surface of flaky copper powder; s2, carrying out surface modification on the flaky copper powder subjected to surface cleaning in the step S1 by adopting an organic treating agent; s3, silver plating is carried out on the surface of the flaky copper powder subjected to the surface modification in the step S2, so that flaky silver-plated copper powder is obtained; The organic treating agent is at least one selected from tea polyphenols, chlorogenic acid and p-hydroxy cinnamic acid. The second object of the invention is to provide the flake silver-plated copper powder with high oxidation resistance, which is obtained by the preparation method. The third object of the invention is to provide the application of the flaky silver-plated copper powder with high oxidation resistance in photovoltaic silver paste. The beneficial effects of the invention are as follows: 1. According to the invention, the organic treating agent is uniformly introduced into the surface of the flaky copper powder in a surface modification mode, the oxidation resistance of the copper powder can be effectively improved by the organic film formed by the organic treating agent, meanwhile, the oxidation resistance of the copper powder is further improved by utilizing the oxidation resistance of phenolic hydroxyl contained in the organic treating agent, and active groups contained in the organic treating agent can be introduced into active sites for subsequent silver plating, so that a uniform and compact silver layer can be formed. 2. The organic antioxidation layer is sandwiched between the copper layer and the silver layer, so that the reliability is higher, the stability is higher, and the conductivity of the product platy silver-plated copper powder is not influenced. Drawings FIG. 1 is an SEM image of flake silver-plated copper powder obtained in example 1; FIG. 2 is a thermogravimetric analysis of the flake silver-coated copper powder obtained in example 1; Fig. 3 is an SEM image of the flake silver-plated c