阅读说明：本技术 泡沫铜及其制备方法和应用 (Foam copper and preparation method and application thereof ) 是由 王进 吕雪玲 曹林洪 黄亚文 符亚军 于 2020-11-27 设计创作，主要内容包括：本发明提供了一种泡沫铜及其制备方法和应用,涉及泡沫铜制备技术领域,上述泡沫铜的制备方法首先以聚氨酯泡沫为基体依次进行预处理、化学沉积、电沉积将金属铜沉积于聚氨酯泡沫上；随后进行热还原处理去除聚氨酯泡沫,得到泡沫铜；其中,所述热还原处理的热还原气体为氢气占体积含量10％的H-2/Ar-2混合气体,因而本发明热还原过程中氢气的使用量较低,进而有效降低了泡沫铜制备的成本和能源消耗,同时上述制备方法还具有制备工艺简单,易于操作的优势。此外,本发明制得的泡沫铜为一个整体形状,相对于现有常规的粉末状泡沫铜,具有更利于后期应用的优势。(The invention provides a foamy copper and a preparation method and application thereof, relating to the technical field of foamy copper preparation, wherein the preparation method of the foamy copper comprises the steps of firstly taking polyurethane foam as a substrate, sequentially carrying out pretreatment, chemical deposition and electrodeposition to deposit metal copper on the polyurethane foam;then, carrying out thermal reduction treatment to remove polyurethane foam to obtain foam copper; wherein the hot reducing gas of the thermal reduction treatment is H with 10 percent of hydrogen volume content 2 /Ar 2 The mixed gas has low consumption of hydrogen in the thermal reduction process, so that the preparation cost and energy consumption of the foam copper are effectively reduced, and the preparation method has the advantages of simple preparation process and easiness in operation. In addition, the foam copper prepared by the invention is in an integral shape, and has the advantage of being more beneficial to later application compared with the conventional powdery foam copper.)

1. The preparation method of the foam copper is characterized by comprising the following steps of:

providing a polyurethane foam; then taking polyurethane foam as a substrate, sequentially carrying out pretreatment, chemical deposition and electrodeposition to deposit metal copper on the polyurethane foam; then, carrying out thermal reduction treatment to remove polyurethane foam to obtain foam copper;

the hot reducing gas of the thermal reduction treatment is H with the volume content of hydrogen being 10 percent₂/Ar₂And (4) mixing the gases.

2. The method of claim 1, wherein the polyurethane foam has a pore size density of 40 to 60 ppi.

3. The method for preparing copper foam according to claim 1, wherein the pretreatment comprises the steps of coarsening, sensitization, activation and dispergation which are sequentially performed.

4. The method for preparing the copper foam according to claim 3, wherein the coarsening solution is a sulfuric acid solution containing potassium permanganate;

more preferably, the coarsening time is 2-3 min;

preferably, the sensitizing solution is hydrochloric acid solution containing stannous chloride;

more preferably, the sensitization time is 5-8 min;

preferably, the activated activating solution is a hydrochloric acid solution containing palladium chloride;

more preferably, the activation time is 5-8 min;

preferably, the dispergation liquid for dispergation is formaldehyde solution;

more preferably, the time for degumming is 3-6 min.

5. The method for preparing copper foam according to claim 1, wherein the electroless plating solution for electroless deposition comprises copper sulfate pentahydrate, potassium sodium tartrate, formaldehyde, sodium hydroxide, potassium ferrocyanide and 2, 2' -bipyridine;

preferably, each L of the chemical plating solution comprises 16-25g of blue vitriol, 16-20g of sodium potassium tartrate, 16-20ml of formaldehyde, 14-20g of sodium hydroxide, 0.1-0.15g of potassium ferrocyanide and 0.1-0.15g of 2, 2' -bipyridyl.

6. The method for preparing copper foam according to claim 5, wherein the deposition time of the chemical deposition is 20-30 min, and the temperature is 60-70 ℃.

7. The method for preparing copper foam according to claim 1, wherein the electroplating solution for electrodeposition comprises copper sulfate pentahydrate, concentrated sulfuric acid, polyethylene glycol and 1, 4-butynediol;

preferably, each L of the electroplating solution comprises 200-250g of blue vitriol, 25-40mL of concentrated sulfuric acid, 0.03-0.04g of polyethylene glycol and 0.2-0.3g of 1, 4-butynediol;

preferably, the electroplating time of the electrodeposition is 20-40 min, the voltage is 1-2V, and the current density is 0.2-0.4A/cm²；

More preferably, the electrodeposition time is 30min, the voltage is 1V, and the current density is 0.35A/cm²。

8. The method for preparing copper foam according to claim 1, wherein the thermal reduction treatment method comprises the following steps: heating to 700 ℃ at a heating rate of less than or equal to 10 ℃/min, and then preserving heat for 1.5-2.5h to obtain the foam copper;

preferably, the method of thermal reduction treatment comprises the steps of: heating to 700 ℃ at a heating rate of less than or equal to 10 ℃/min, and then preserving heat for 1.5-2.5h to obtain the foam copper.

9. A copper foam produced by the method for producing a copper foam according to any one of claims 1 to 8.

10. Use of the copper foam according to claim 9 for the preparation of battery negative electrode materials, phase change energy storage device filling materials, electromagnetic shielding materials and/or catalyst supports.

Technical Field

The invention relates to the technical field of preparation of copper foam, in particular to copper foam and a preparation method and application thereof.

Background

The foam copper is a novel light multifunctional material with a large number of communicated holes uniformly distributed in a copper metal matrix, and has the characteristics of small density, high porosity, large specific surface area and the like. With the progress of modern electronic and optical technologies and the improvement of aerospace flight mission requirements, a series of high-power components with ultrahigh heat flow density, short-time and intermittent operation are urgently needed, and as the preparation cost of the copper foam is lower than that of the nickel foam and the electric conductivity is better, the copper foam is widely used for replacing the nickel foam to prepare battery cathode materials, phase change energy storage device filling materials, electromagnetic shielding materials and catalyst carriers.

The existing preparation methods of the foam copper are roughly divided into a directional solidification method, a seepage casting method, a powder metallurgy method, a dealloying method, an electrodeposition method and the like. However, the existing methods also have certain problems, which are as follows: 1. a directional solidification method: the method is characterized in that the gas has poor solubility in a metal liquid phase and a solid phase, supersaturated gas is separated out from the front edge of a solid-liquid interface during solidification, and the growth speed of bubbles is matched with the solidification speed of the metal by controlling process parameters, so that the porous metal with a directionally-grown regular pore structure is obtained. The difficulty with this approach is the uniform distribution and size of the gas outlet holes. 2. And (3) seepage casting: the granules are first deposited in a mould, or the porous prefabricated blocks are placed in a mould, and then the molten metal is infiltrated into the pores of the deposited or porous prefabricated bodiesAfter the metal melt is solidified, the space occupying materials are removed, and then the metal material with a porous structure can be obtained. This method also has disadvantages. Mainly reflected in the influence of technical conditions such as seepage pressure, temperature and the like, and the prepared product often has insufficient or excessive seepage. Uneven fluid distribution during seepage causes uneven porosity and the like. 3. Powder metallurgy: adding 2 mass percent of Al into Cu powder with the purity of 99.9 percent₂O₃Nano particles and foaming agent K with mass fraction of l 5% -50%₂CO, followed by mixing the mixed powder in a planetary ball mill for 4 h; and pressing the uniformly mixed powder to obtain a precursor, wherein the pressure used in pressing is 250 MPa: and finally, sintering and foaming the precursor in an oxygen-free environment. The sintering temperature and the foaming temperature are respectively 850 ℃, 1000 ℃ and K₂C0₃And the gas generated by decomposition foams the precursor to obtain the foam copper. The method has long time for process requirement and higher equipment requirement. 4. Dealloying: also known as selective corrosion, is a corrosion process in which active elements are selectively dissolved into an electrolyte under the action of an electrolyte by using an electrode potential difference between alloy components or electrochemical properties in the alloy, thereby leaving more stable elements. The method can be used for preparing the nano-porous copper and has the problems of serious pollution, difficult recovery and the like.

The electro-deposition method is also a preparation method of foamy copper which is widely applied in the prior art, and the principle of preparing the foamy copper is that a thin metal film is obtained on an organic matrix with a net structure through chemical plating so as to enable the matrix to have conductivity, and then a layer of metal is plated on the surface of the matrix through an electroplating method. Finally, the organic matrix is removed by firing to obtain a metal foam having a spatial network structure.

However, the existing electrodeposition method for preparing the copper foam has the defects of large environmental pollution, high cost, long production time, large demand on hydrogen and the like.

Therefore, in view of the defects of the existing copper foam preparation method, it is necessary and urgent to develop a copper foam preparation process which is low in hydrogen consumption, short in production time and environment-friendly.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

The first purpose of the invention is to provide a preparation method of copper foam, wherein the hot reducing gas in the heat reduction treatment in the preparation method is H with lower hydrogen content₂/Ar₂And the preparation method also has the advantages of simple preparation process and easy operation.

The second purpose of the invention is to provide the copper foam, which is prepared by the preparation method of the copper foam.

The third purpose of the invention is to provide an application of the copper foam, and the copper foam can be widely applied to the preparation process of battery negative electrode materials, phase change energy storage device filling materials, electromagnetic shielding materials and/or catalyst carriers.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

the invention provides a preparation method of foam copper, which comprises the following steps:

providing a polyurethane foam; then taking polyurethane foam as a substrate, sequentially carrying out pretreatment, chemical deposition and electrodeposition to deposit metal copper on the polyurethane foam; then, carrying out thermal reduction treatment to remove polyurethane foam to obtain foam copper;

the hot reducing gas of the thermal reduction treatment is H with the volume content of hydrogen being 10 percent₂/Ar₂And (4) mixing the gases.

Further, the pore diameter of the polyurethane foam is 40-60 ppi.

Further, the pretreatment comprises the steps of coarsening, sensitizing, activating and dispergating which are sequentially carried out;

preferably, the coarsening liquid is a sulfuric acid solution containing potassium permanganate;

more preferably, the coarsening time is 2-3 min;

preferably, the sensitizing solution is hydrochloric acid solution containing stannous chloride;

more preferably, the sensitization time is 5-8 min;

preferably, the activated activating solution is a hydrochloric acid solution containing palladium chloride;

more preferably, the activation time is 4-6 min;

preferably, the dispergation liquid for dispergation is formaldehyde solution;

more preferably, the time for degumming is 3-6 min.

Further, the chemical plating solution for chemical deposition comprises copper sulfate pentahydrate, sodium potassium tartrate, formaldehyde, sodium hydroxide, potassium ferrocyanide and 2, 2' -bipyridine;

preferably, each L of the chemical plating solution comprises 16-25g of blue vitriol, 16-20g of sodium potassium tartrate, 16-20ml of formaldehyde, 14-20g of sodium hydroxide, 0.1-0.15g of potassium ferrocyanide and 0.1-0.12g of 2, 2' -bipyridyl.

Furthermore, the deposition time of the chemical deposition is 20-30 min, and the temperature is 60-70 ℃.

Furthermore, the electroplating solution for electrodeposition comprises copper sulfate pentahydrate, polyethylene glycol and 1, 4-butynediol;

preferably, each L of the electroplating solution comprises 200-250g of blue vitriod, 0.03-0.04g of concentrated sulfuric acid 25-40 g of polyethylene glycol and 0.2-0.3g of 1, 4-butynediol;

preferably, the electroplating time of the electrodeposition is 20-30 min, the voltage is 1-2V, and the current density is 0.2-0.4A/cm²；

More preferably, the electroplating time of the electrodeposition is 25min, the voltage is 1V, and the current density is 0.4A/cm²。

Further, the method for thermal reduction treatment comprises the following steps: heating to 700 ℃ at a heating rate of less than or equal to 10 ℃/min, and then preserving heat for 1.5-2.5h to obtain the foam copper;

preferably, the method of thermal reduction treatment comprises the steps of: heating to 700 ℃ at the heating rate of 10 ℃/min, and then preserving heat for 2h to obtain the foam copper.

The invention provides the foamy copper prepared by the preparation method of the foamy copper.

The invention provides an application of the foamy copper in preparation of battery negative electrode materials, phase change energy storage device filling materials, electromagnetic shielding materials and/or catalyst carriers.

Compared with the prior art, the invention has the beneficial effects that:

the preparation method of the foam copper provided by the invention comprises the following steps of firstly, taking polyurethane foam as a substrate, sequentially carrying out pretreatment, chemical deposition and electrodeposition to deposit metal copper on the polyurethane foam; then, carrying out thermal reduction treatment to remove polyurethane foam to obtain foam copper; wherein the hot reducing gas of the thermal reduction treatment is H with 10 percent of hydrogen volume content₂/Ar₂And the mixed gas is adopted, so that the consumption of hydrogen in the thermal reduction process of the method is low (the conventional gas is CO and pure hydrogen), the preparation cost and the energy consumption of the copper foam are effectively reduced, and the preparation method also has the advantages of simple preparation process and easiness in operation.

The foamy copper provided by the invention is prepared by the preparation method of the foamy copper, and the foamy copper has the advantages of strong toughness (the thickness of a copper layer is increased by adjusting the thickness of an electroplating copper layer through electroplating time and concentration of electroplating solution, the toughness is increased), high conductivity (the density of the copper layer is increased by chemical plating and electroplating copper), and the foamy copper prepared by the invention is in an integral shape, and has the advantage of being more beneficial to later-stage application compared with the conventional powdery foamy copper.

The foamy copper provided by the invention can be widely applied to the preparation process of battery cathode materials, phase change energy storage device filling materials, electromagnetic shielding materials and/or catalyst carriers.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a microscopic structure view of a polyurethane foam provided in example 1 of the present invention;

FIG. 2 is a physical sensory diagram of the prepared copper foam provided in example 1 of the present invention;

FIG. 3 is a scanning electron microscope topography of the prepared copper foam provided in example 1 of the present invention;

fig. 4 is an XRD spectrum of the copper foam prepared in examples 1 to 6 of the present application, which is provided in experimental example 1 of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

According to one aspect of the present invention, a method for preparing copper foam comprises the steps of:

providing a polyurethane foam; then taking polyurethane foam as a substrate, sequentially carrying out pretreatment, chemical deposition and electrodeposition to deposit metal copper on the polyurethane foam; then, carrying out thermal reduction treatment to remove polyurethane foam to obtain foam copper;

the hot reducing gas of the thermal reduction treatment is H with the volume content of hydrogen being 10 percent₂/Ar₂And (4) mixing the gases.

The preparation method of the foam copper provided by the invention comprises the following steps of firstly, taking polyurethane foam as a substrate, sequentially carrying out pretreatment, chemical deposition and electrodeposition to deposit metal copper on the polyurethane foam; then, carrying out thermal reduction treatment to remove polyurethane foam to obtain foam copper; wherein the hot reducing gas of the thermal reduction treatment is H with 10 percent of hydrogen volume content₂/Ar₂The mixed gas is adopted, so the usage amount of hydrogen in the thermal reduction process of the method is low(conventional gases are CO, pure hydrogen, N₂/H₂1:3), so as to effectively reduce the cost and energy consumption of the preparation of the foamy copper, and meanwhile, the preparation method also has the advantages of simple preparation process and easy operation.

In a preferred embodiment of the present invention, the polyurethane foam has a pore size density of 40 to 60 ppi.

In a preferred embodiment, the polyurethane foam has a pore size density of 60 ppi.

In a preferred embodiment of the present invention, the pretreatment comprises the steps of roughening, sensitizing, activating and dispergating, which are performed in sequence;

in the above preferred embodiment, the roughening solution is a sulfuric acid solution containing potassium permanganate; the coarsening time is 2-3 min;

in a preferred embodiment, the roughening is to form a plurality of microscopic amorphous pits on the surface of the polyurethane skeleton, and during electroless plating, metal particles are deposited in the pits to form a plurality of riveting points, which is beneficial to improving the bonding force of the plating layer. And the hydrophilic group is added, so that the subsequent treatment is facilitated.

In the above preferred embodiment, the sensitizing solution is a hydrochloric acid solution containing stannous chloride; the sensitization time is 5-8 min;

as a preferred embodiment, the sensitization is intended to induce the deposition reaction by forming catalytic metal nuclei, generally referred to as activation sites, on the surface of the substrate. The formation process of the active center is a microscopic metal reduction process, a layer of reducing liquid film with reduction effect is formed on the surface of the plating base body through the action of the sensitizing solution, and then catalytic metal nuclei are reduced in the activating solution containing the active metal ions.

In the above preferred embodiment, the activated activating solution is a hydrochloric acid solution containing palladium chloride; the activation time is 4-6 min;

in a preferred embodiment, the sensitized polyurethane foam surface adsorbs a stannous ion liquid film, but the stannous salt does not have catalytic activity per se, and can only help the reduction deposition of metal ions with catalytic activity, so that the sensitized sample must be subjected to an activation treatment. The nature of the activation is a reduction reaction of the active metal. The noble metal particles generated by reduction are generally in a gel state, have high surface activity and can be adsorbed on the surface of a polyurethane framework. In the subsequent implementation process of the matrix electroless plating, the layer of gelatinous high-activity metal particles become the key of the electroless plating, namely catalytic centers generated by the plating layer, and the key condition is that the electroless plating can be performed spontaneously.

In the above preferred embodiment, the dispergation solution for dispergation is formaldehyde solution; the time for degumming is 3-6 min.

In a preferred embodiment of the present invention, the electroless plating solution for electroless deposition comprises copper sulfate pentahydrate, sodium potassium tartrate, formaldehyde, sodium hydroxide, potassium ferrocyanide and 2, 2' -bipyridine;

in the above preferred embodiment, the electroless plating solution comprises 16g of copper sulfate pentahydrate, 16g of sodium potassium tartrate, 16ml of formaldehyde, 14g of sodium hydroxide, 0.1g of potassium ferrocyanide and 0.1g of 2, 2' -bipyridine per L.

Preferably, the preparation method of the electroless plating solution comprises the following steps: preparing solution A: weighing 1.60g of copper sulfate pentahydrate, 1.6g of potassium sodium tartrate, 1.4g of sodium hydroxide, 0.01g of potassium ferrocyanide and 0.01g of 2,2 ' -bipyridine, weighing 1.6ml of formaldehyde, firstly weighing 30-40ml of deionized water in a 100ml beaker, adding the copper sulfate pentahydrate and the potassium sodium tartrate, stirring until the copper sulfate pentahydrate and the potassium sodium tartrate are dissolved, adding the weighed formaldehyde solution, stirring, then adding the sodium hydroxide, stirring until the sodium hydroxide is completely dissolved, preparing solution B, dissolving the potassium ferrocyanide and the 2,2 ' -bipyridine in the beaker filled with about 30ml of deionized water, stirring until the potassium ferrocyanide and the 2,2 ' -bipyridine are completely dissolved, finally pouring the solution B into the solution A, mixing and fixing the volume to 100 ml.

In a preferred embodiment of the present invention, the deposition time of the chemical deposition is 20 to 30min, and the temperature is 60 to 70 ℃.

In a preferred embodiment, the chemical deposition time is favorable for the surface coating of the polyurethane skeleton to be uniform, the temperature is increased to accelerate the reaction rate, and the solution is decomposed too fast at a high temperature, so that the polyurethane surface coating is less and the surface coating is not uniform.

In a preferred embodiment of the present invention, the electroplating solution for electrodeposition comprises copper sulfate pentahydrate, concentrated sulfuric acid, polyethylene glycol and 1, 4-butynediol;

in the above preferred embodiment, each L of the plating solution comprises 200g of copper sulfate pentahydrate, 0.03g of polyethylene glycol and 0.2g of 1, 4-butynediol;

preferably, the preparation method of the electroplating solution is as follows: firstly, 20g of blue vitriod is dissolved in a 100ml beaker, 0.003g of polyethylene glycol and 0.02g of 1, 4-butynediol are added into the 100ml beaker for dissolution, 8.4ml of concentrated sulfuric acid is slowly added, then deionized water is added to the volume of 100ml, and the mixture is stirred until all the raw materials are fully dissolved to obtain the electroplating solution.

In a preferred embodiment of the present invention, the electroplating time of the electrodeposition is 20 to 30min, the voltage is 1 to 2V, and the current density is 0.2 to 0.4A/cm²；

As a preferred embodiment, the electrodeposition has the characteristics of low voltage and low current, thereby reducing the cost and energy consumption and reducing the danger coefficient of production.

Preferably, the electroplating time of the electrodeposition is 25min, the voltage is 1V, and the current density is 0.2A/cm²。

In a preferred embodiment of the present invention, the method of thermal reduction treatment comprises the steps of: heating to 700 ℃ at a heating rate of less than or equal to 10 ℃/min, and then preserving heat for 1.5-2.5h to obtain the foam copper;

in a preferred embodiment, the thermal reduction temperature is an optimum thermal reduction temperature, and the polyurethane in the copper foam obtained by thermal reduction at a temperature lower than 600 ℃ is not completely burned off. The foam copper obtained by thermal reduction at 700 ℃ has good toughness.

Preferably, the method of thermal reduction treatment comprises the steps of: heating to 700 ℃ at the heating rate of 10 ℃/min, and then preserving heat for 2h to obtain the foam copper.

According to one aspect of the invention, the copper foam is prepared by the preparation method of the copper foam.

The foamy copper provided by the invention is prepared by the preparation method of the foamy copper, and the foamy copper has the advantages of strong toughness and high conductivity through detection.

According to one aspect of the invention, the copper foam is applied to preparation of battery negative electrode materials, phase change energy storage device filling materials, electromagnetic shielding materials and/or catalyst carriers.

The foamy copper provided by the invention can be widely applied to the preparation process of battery cathode materials, phase change energy storage device filling materials, electromagnetic shielding materials and/or catalyst carriers.

The technical solution of the present invention will be further described with reference to examples and comparative examples.

Example 1

A preparation method of copper foam comprises the following steps:

(1) and cleaning: firstly, polyurethane foam is cleaned, and the aperture of the polyurethane is 40-60 ppi; the structure of the polyurethane foam is shown in figure 1;

FIG. 1 is a microscopic structure of the polyurethane foam provided in this example;

(2) and coarsening: weighing 1.3g of potassium permanganate, adding about 90ml of deionized water into a 100ml beaker, weighing 7ml of concentrated sulfuric acid in a ventilation window, slowly pouring the concentrated sulfuric acid into the beaker while stirring, so as to be beneficial to heat dissipation of the concentrated sulfuric acid, preventing the concentrated sulfuric acid from being poured into water to burst and crack the bottom of the beaker, then adding the weighed potassium permanganate, stirring until the potassium permanganate is completely dissolved, finally fixing the volume to 100ml, and soaking the cleaned polyurethane foam in a roughening solution for 2 min;

(3) and sensitizing: cleaning coarsened polyurethane foam, and then carrying out sensitization treatment, wherein the sensitization liquid is prepared by weighing 2g of stannous chloride, adding 4ml of hydrochloric acid into a 100ml beaker, then pouring the stannous chloride into the beaker, stirring until the stannous chloride is completely dissolved, then adding deionized water to the beaker to reach a constant volume of 100ml, and finally adding one tin particle for sensitization for 5 min;

(4) and activating: cleaning sensitized polyurethane foam, then soaking the polyurethane foam in an activation solution, firstly weighing 0.02g of palladium chloride, adding 90ml of deionized water into a beaker, weighing 0.1ml of hydrochloric acid, pouring the hydrochloric acid into the beaker, uniformly stirring, adding the weighed palladium chloride, stirring until the palladium chloride is completely dissolved, adding the cleaned polyurethane foam, and activating for 5 min.

(5) And peptizing: carrying out degumming on the activated foam, measuring 0.3ml of formaldehyde into 100ml of deionized water, adjusting the ph to be 8, and soaking the foam after cleaning for 2 min;

(6) and chemical plating:

(6.1) preparing an electroless plating solution:

preparing solution A: weighing 1.60g of copper sulfate pentahydrate, 1.6g of potassium sodium tartrate, 1.4g of sodium hydroxide, 0.01g of potassium ferrocyanide and 0.01g of 2,2 ' -bipyridine, weighing 1.6ml of formaldehyde, firstly weighing 30-40ml of deionized water in a 100ml beaker, adding the copper sulfate pentahydrate and the potassium sodium tartrate, stirring until the copper sulfate pentahydrate and the potassium sodium tartrate are dissolved, adding the weighed formaldehyde solution, stirring, then adding the sodium hydroxide, stirring until the sodium hydroxide is completely dissolved, preparing solution B, dissolving the potassium ferrocyanide and the 2,2 ' -bipyridine in the beaker filled with about 30ml of deionized water, stirring until the potassium ferrocyanide and the 2,2 ' -bipyridine are completely dissolved, finally pouring the solution B into the solution A, mixing and fixing the volume to 100 ml.

(6.2) placing the polyurethane foam after the peptization into chemical plating solution for deposition and soaking for 30min, keeping the temperature at 65 ℃, and occasionally stirring the solution during the chemical plating process to make the plating solution uniform, so that ions can pass through the foam.

(7) And electroplating: using a direct current power supply device as an electrolytic bath, washing and soaking the foams after chemical plating into electroplating solution to be used as a cathode, using a metal copper sheet as an anode, and depositing a metal copper plating layer on the foams after the direct current power supply is connected;

the preparation method of the electroplating solution comprises the following steps: firstly, adding 20g of copper sulfate pentahydrate, 3.36g of concentrated sulfuric acid, 0.003g of polyethylene glycol and 0.02g of 1, 4-butynediol into a 100ml beaker, then adding deionized water to a constant volume of 100ml, and stirring until all raw materials are fully dissolved to obtain the electroplating solution.

The electroplating time is 30min, and the voltage: 1V, and the apparent current density is 0.4A/cm²。

(8) And thermal reduction: cleaning the electroplated foam copper with deionized water and absolute ethyl alcohol, putting the cleaned foam copper into a tubular furnace, vacuumizing the furnace to be below 100Pa, and introducing H with the hydrogen content of 10 percent₂/Ar₂Mixing the gases until the pressure in the pipe reaches the atmospheric pressure, opening an outlet valve, keeping the pressure in the pipe to be the same as the atmospheric pressure, setting the heating rate to be 10 ℃ per minute, heating the temperature to 700 ℃, preserving the heat for 2 hours, naturally cooling the temperature, keeping the hydrogen flow to be 74sccm, and carrying out thermal reduction to obtain the foam copper with the polyurethane material removed.

Then, the copper foam prepared in the embodiment is subjected to character identification, and specific results are shown in fig. 2 and fig. 3;

FIG. 2 is a physical image of the copper foam obtained in this example;

fig. 3 is a scanning electron microscope topography of the copper foam prepared in this example.

Examples 2 to 6

The following examples are similar to example 1 except that the electroless plating solution deposition soaking time in step (6.2) and the electroplating time in step (7) are different from example 1, and are specifically shown in the following table:

group of	Chemical plating bath deposition soaking (min)	Time of plating (min)
			Example 2	30	30
Example 3	30	40
			Example 4	40	20
Example 5	40	30
			Example 6	40	40

Experimental example 1

The applicant carries out XRD pattern detection on the copper foams prepared in the embodiments 2-6 and the embodiment 1, and the result is shown in figure 4;

FIG. 4 is an XRD pattern of copper foams obtained in examples 1 to 6 of the present application; pure copper with good crystallinity is obtained by different preparation parameters.

Example 7

A preparation method of copper foam comprises the following steps:

(1) and cleaning: firstly, cleaning polyurethane foam, wherein the pore diameter of polyurethane is 40 ppi;

(2) and coarsening: weighing 1.3g of potassium permanganate, adding about 90ml of deionized water into a 100ml beaker, weighing 7ml of concentrated sulfuric acid in a ventilation window, slowly pouring the concentrated sulfuric acid into the beaker while stirring, so as to be beneficial to heat dissipation of the concentrated sulfuric acid, preventing the concentrated sulfuric acid from being poured into water to burst and crack the bottom of the beaker, then adding the weighed potassium permanganate, stirring until the potassium permanganate is completely dissolved, finally fixing the volume to 100ml, and soaking the cleaned polyurethane foam in a roughening solution for 3 min;

(3) and sensitizing: cleaning coarsened polyurethane foam, and then carrying out sensitization treatment, wherein the sensitization liquid is prepared by weighing 2g of stannous chloride, adding 4ml of hydrochloric acid into a 100ml beaker, then pouring the stannous chloride into the beaker, stirring until the stannous chloride is completely dissolved, then adding deionized water to the beaker to reach a constant volume of 100ml, and finally adding one tin particle for sensitization for 8 min;

(4) and activating: cleaning the sensitized polyurethane foam, then soaking the polyurethane foam in an activation solution, firstly weighing 0.02g of palladium chloride, adding 90ml of deionized water into a beaker, weighing 0.1ml of hydrochloric acid, pouring the hydrochloric acid into the beaker, uniformly stirring, adding the weighed palladium chloride, stirring until the palladium chloride is completely dissolved, adding the cleaned polyurethane foam, and activating for 6 min.

(5) And dispergating; carrying out degumming on the activated foam, measuring 0.3ml of formaldehyde into 100ml of deionized water, adjusting the ph to be 8, and soaking the foam after cleaning for 4 min;

(6) and chemical plating:

(6.1) preparing electroless plating solution in the same way as in example 1;

(6.2) placing the polyurethane foam after the peptization into chemical plating solution for deposition and soaking for 20min, keeping the temperature at 70 ℃, and occasionally stirring the solution during the chemical plating process to make the plating solution uniform, so that ions can pass through the foam.

(7) And electroplating: the same procedure as in example 1 except for the plating time;

the electroplating time is 30min, and the voltage: 1V, and the apparent current density is 0.2A/cm²。

(8) And thermal reduction: the same as in example 1.

Comparative example 1

The roughening solution is added with chromium trioxide for roughening treatment besides potassium permanganate and concentrated sulfuric acid. The dispergation process adopts 10% hydrochloric acid solution to wash for one minute, and the electroplating solution comprises copper sulfate pentahydrate, concentrated sulfuric acid, polyethylene glycol, sodium chloride and lauryl sodium sulfate. The thermal reduction is carried out by adopting N2/H21: 3, the gas is thermally reduced. The experiment uses more materials, the process is complex, and the thermal reduction adopts gas with high hydrogen content.

Experimental example 2

Tests prove that the plating layer of the foam copper can be thickened and the electroplating is uniform when the foam copper is electroplated, so that higher conductivity is obtained; the toughness is increased by increasing the time of thermal reduction.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.