阅读说明：本技术 一种表面具有片状叠层结构的棒状银粉制备方法 (Preparation method of rod-like silver powder with flaky laminated structure on surface ) 是由 张亚红 齐勇 曹笃盟 杨建强 范秀娟 吴来红 包飞燕 王维斌 王国强 王悦 乔天 于 2021-08-25 设计创作，主要内容包括：本发明涉及棒状银粉技术领域,具体为一种表面具有片状叠层结构的棒状银粉制备方法,包括以下步骤,步骤一、将硝酸银送入搅拌器内,加入水后以35r/min对其搅拌5min后得到硝酸银溶液；步骤二、将步骤一中所得的硝酸银溶液送器皿内,加入一定比例的形貌控制试剂；步骤三、控制电解过程的电压和电流、阴阳极间距、刷粉周期得到银粉。本发明通过对比六种表面具有片状叠层结构的棒状银粉制备方法,六种表面具有片状叠层结构的棒状银粉制备方法均可制作出表面具有片状叠层结构的棒状银粉,不同于目前电解生产技术制备的结晶粗大的枝晶状银粉,该方法所制备的银粉表面具有片状叠层结构,提供了较大的比表面积,可以应用于催化和抗菌等领域。(The invention relates to the technical field of rod-shaped silver powder, in particular to a method for preparing rod-shaped silver powder with a flaky laminated structure on the surface, which comprises the following steps of firstly, feeding silver nitrate into a stirrer, adding water, and stirring for 5min at 35r/min to obtain a silver nitrate solution; step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a certain proportion of morphology control reagent is added; and step three, controlling the voltage and current in the electrolytic process, the cathode-anode distance and the brushing period to obtain the silver powder. According to the invention, compared with six rod-shaped silver powder preparation methods with the sheet-shaped laminated structure on the surface, the six rod-shaped silver powder preparation methods with the sheet-shaped laminated structure on the surface can prepare the rod-shaped silver powder with the sheet-shaped laminated structure on the surface, and the method is different from the traditional electrolysis production technology for preparing coarse crystallized dendritic silver powder.)

1. A method for preparing rodlike silver powder with a flaky laminated structure on the surface is characterized in that the method is an electrolysis method and comprises the following steps:

step one, feeding silver nitrate into a stirrer, adding water, and stirring for 5min at 35r/min to obtain a silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a certain proportion of morphology control reagent is added;

step three, controlling the voltage and current in the electrolysis process, the cathode-anode distance and the brushing period to obtain silver powder;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 0.5-1 h, and drying to obtain the rod-shaped silver powder with the surface having the flaky laminated structure.

2. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: the silver powder is rod-shaped, the length of the silver powder is 50-100 mu m, the diameter of the silver powder is 10-30 mu m, and the surface of the silver powder is of a flaky laminated structure.

3. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: the rod-like silver powder with the flaky laminated structure on the surface can be obtained by adding a morphology control reagent into the electrolyte, controlling the current in the electrolytic process, the brushing period and other factors.

4. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: in the third step, the cathode is a titanium plate, the anode is a coarse silver plate, and the distance between the electrodes is 5-20 cm.

5. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: and in the third step, electrolysis is carried out in a constant current mode, wherein the electrolysis current is 3-20A/dm 2.

6. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: and in the third step, after electrolyzing for a certain time, brushing off silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 10-60 s/time.

7. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: the silver powder with the flaky laminated open structure on the surface can be obtained by adding a morphology control reagent into an electrolyte, wherein the electrolyte is a silver nitrate solution with the concentration of 10-50 g/L.

8. The method for producing a silver powder having a rod-like silver powder with a plate-like layered structure on the surface thereof according to claim 1, wherein: the silver powder with the flaky laminated open structure on the surface can be obtained by adding a morphology control reagent into the electrolyte, wherein the morphology control reagent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, the mass ratio of the morphology control reagent to the silver nitrate is 20:10:2:1, and the mass ratio of the morphology control reagent to the silver nitrate added into the electrolyte is 1: 1-1: 10.

Technical Field

The invention relates to the technical field of rod-shaped silver powder, in particular to a preparation method of rod-shaped silver powder with a flaky laminated structure on the surface.

Background

With the high-speed innovation and development of electronic, information and microelectronic technologies, environmental protection, precision and miniaturization become the development direction of electronic components, and the requirements on the performance of the conductive paste are higher and higher.

The electrolytic silver powder prepared by the method is generally dendritic and is applied to preparation of alloy materials. The preparation technology of electrolytic silver powder at home and abroad mainly researches the preparation conditions of dendritic silver powder: preparing dendrite silver powder with smaller grain size by a constant current electrolysis method and taking a nitric acid and silver nitrate system as an electrolyte; ljiljana Avramovi' c and the like research that a nitric acid electrolyte forms acicular dendrites and a mixture of irregular and regular crystals, and an ammonia electrolyte forms apparent pine dendrites consisting of spherical particles; the Liao red science and the like prepare dendritic crystal nano silver by an electrochemical method in the presence of a complexing agent N-hydroxyethyl ethylenediamine-N, N, N-triacetic acid, and a preparation technology of rodlike silver powder with a flaky laminated structure on the surface is not reported at home and abroad, so that a preparation method of rodlike silver powder with a flaky laminated structure on the surface is urgently needed.

Disclosure of Invention

The invention aims to provide a method for preparing rodlike silver powder with a flaky laminated structure on the surface, which aims to solve the problems that the Liaohong science and the like in the background technology use an electrochemical method to prepare dendritic nano silver in the presence of a complexing agent N-hydroxyethyl ethylenediamine-N, N, N-triacetic acid, and the preparation technology of rodlike silver powder with a flaky laminated structure on the surface is not reported at home and abroad.

In order to achieve the purpose, the invention provides the following technical scheme: a method for preparing rodlike silver powder with a flaky laminated structure on the surface comprises the following steps:

step one, feeding silver nitrate into a stirrer, adding water, and stirring for 5min at 35r/min to obtain a silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a certain proportion of morphology control reagent is added;

step three, controlling the voltage and current in the electrolysis process, the cathode-anode distance and the brushing period to obtain silver powder;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 0.5-1 h, and drying to obtain the rod-shaped silver powder with the surface having the flaky laminated structure.

Preferably, the silver powder is rod-shaped, the length of the silver powder is 50-100 mu m, the diameter of the silver powder is 10-30 mu m, and the surface of the silver powder is of a flaky laminated structure.

Preferably, the rod-like silver powder with the flaky laminated structure on the surface can be obtained by adding a morphology control reagent into the electrolyte, controlling the current of the electrolysis process, and the brushing period.

Preferably, in the third step, the cathode is a titanium plate, the anode is a coarse silver plate, and the distance between the electrodes is 5-20 cm.

Preferably, in the third step, electrolysis is carried out in a constant current mode, and the electrolysis current is 3-20A/dm 2.

Preferably, the silver powder separated out from the titanium cathode plate is brushed away by a brush after electrolysis for a certain time in the third step, and the brushing period is 10-60 s/time.

Preferably, the silver powder with the flaky laminated open structure on the surface can be obtained by adding a morphology control reagent into an electrolyte, wherein the electrolyte is a silver nitrate solution with the concentration of 10-50 g/L.

Preferably, the silver powder with the flaky laminated open structure on the surface can be obtained by adding a morphology control agent into the electrolyte, the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, the mass ratio of the morphology control agent to the silver nitrate is 20:10:2:1, and the mass ratio of the morphology control agent to the silver nitrate added into the electrolyte is 1: 1-1: 10.

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

according to the invention, compared with six rod-shaped silver powder preparation methods with the sheet-shaped laminated structure on the surface, the six rod-shaped silver powder preparation methods with the sheet-shaped laminated structure on the surface can prepare the rod-shaped silver powder with the sheet-shaped laminated structure on the surface, and the method is different from the traditional electrolysis production technology for preparing coarse crystallized dendritic silver powder.

Drawings

FIG. 1 is a schematic view of SEM (250 times) of a rod-like silver powder having a lamellar stacking structure according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.

Referring to fig. 1, an embodiment of the present invention:

a method for preparing rodlike silver powder with a flaky laminated structure on the surface comprises the following steps:

step one, feeding silver nitrate into a stirrer, adding water, and stirring for 5min at 35r/min to obtain a silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a certain proportion of morphology control reagent is added;

step three, controlling the voltage and current in the electrolysis process, the cathode-anode distance and the brushing period to obtain silver powder;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 0.5-1 h, and drying to obtain the rod-shaped silver powder with the surface having the flaky laminated structure.

Further, the silver powder is rod-shaped, the length of the silver powder is 50-100 mu m, the diameter of the silver powder is 10-30 mu m, and the surface of the silver powder is of a flaky laminated structure.

Further, by adding a morphology control reagent into the electrolyte, controlling the current in the electrolytic process, and controlling the brushing period, the rod-like silver powder with the flaky laminated structure on the surface can be obtained.

Furthermore, in the third step, the cathode is a titanium plate, the anode is a coarse silver plate, and the distance between the electrodes is 5-20 cm.

Further, in the third step, electrolysis is carried out in a constant current mode, and the electrolysis current is 3-20A/dm 2.

Further, silver powder separated out from the titanium cathode plate is brushed away by a brush after electrolysis is carried out for a certain time in the third step, and the brushing period is 10-60 s/time.

Further, silver powder with a flaky laminated open structure on the surface can be obtained by adding a morphology control reagent into electrolyte, wherein the electrolyte is silver nitrate solution with the concentration of 10-50 g/L.

Further, silver powder with a flaky laminated open structure on the surface can be obtained by adding a morphology control agent into the electrolyte, wherein the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, the mass ratio of the morphology control agent to the silver nitrate is 20:10:2:1, and the mass ratio of the morphology control agent added into the electrolyte to the silver nitrate is 1: 1-1: 10.

The first embodiment is as follows:

step one, feeding silver nitrate into a stirrer, adding water, and stirring at 35r/min for 5min to obtain 10g/L silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a morphology control agent is added according to the mass ratio of 1: 1; the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, and the mass ratio of the morphology control agent to the ammonium citrate salt is 20:10:2: 1;

step three, adopting a constant-current electrolysis method, wherein the cathode is a titanium plate, the anode is a coarse silver plate, the inter-polar distance is 5cm, and the current is 20A/dm 2; after electrolyzing for a certain time, brushing off silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 30 s;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 0.5h, and obtaining the rod-shaped silver powder with the surface having the flaky laminated structure after drying.

Example two:

step one, feeding silver nitrate into a stirrer, adding water, and stirring at 35r/min for 5min to obtain 30g/L silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a morphology control agent is added according to the mass ratio of 1: 1; the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, and the mass ratio of the morphology control agent to the ammonium citrate salt is 20:10:2: 1;

step three, adopting a constant-current electrolysis method, wherein the cathode is a titanium plate, the anode is a coarse silver plate, the inter-polar distance is 10cm, and the current is 10A/dm 2; after electrolyzing for a certain time, brushing off silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 30 s;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 0.5h, and obtaining the rod-shaped silver powder with the surface having the flaky laminated structure after drying.

Example three:

step one, feeding silver nitrate into a stirrer, adding water, and stirring at 35r/min for 5min to obtain 10g/L silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a morphology control agent is added according to the mass ratio of 1: 1; the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, and the mass ratio of the morphology control agent to the ammonium citrate salt is 20:10:2: 1;

step three, adopting a constant-current electrolysis method, wherein the cathode is a titanium plate, the anode is a coarse silver plate, the inter-polar distance is 20cm, and the current is 50A/dm 2; after electrolyzing for a certain time, brushing off silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 30 s;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 0.8h, and drying to obtain the rod-shaped silver powder with the surface having the flaky laminated structure.

Example four:

step one, feeding silver nitrate into a stirrer, adding water, and stirring at 35r/min for 5min to obtain 40g/L silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a morphology control agent is added according to the mass ratio of 1: 1; the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, and the mass ratio of the morphology control agent to the ammonium citrate salt is 20:10:2: 1;

step three, adopting a constant-current electrolysis method, wherein the cathode is a titanium plate, the anode is a coarse silver plate, the inter-polar distance is 15cm, and the current is 15A/dm 2; after electrolyzing for a certain time, brushing silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 40 s;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 1h, and obtaining the rod-shaped silver powder with the surface having the flaky laminated structure after drying.

Example five:

step one, feeding silver nitrate into a stirrer, adding water, and stirring at 35r/min for 5min to obtain 45g/L silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a morphology control agent is added according to the mass ratio of 1: 1; the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, and the mass ratio of the morphology control agent to the ammonium citrate salt is 20:10:2: 1;

step three, adopting a constant-current electrolysis method, wherein the cathode is a titanium plate, the anode is a coarse silver plate, the inter-polar distance is 20cm, and the current is 10A/dm 2; after electrolyzing for a certain time, brushing silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 20 s;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 1h, and obtaining the rod-shaped silver powder with the surface having the flaky laminated structure after drying.

Example six:

step one, feeding silver nitrate into a stirrer, adding water, and stirring at 35r/min for 5min to obtain 50g/L silver nitrate solution;

step two, the silver nitrate solution obtained in the step one is sent into a vessel, and a morphology control agent is added according to the mass ratio of 1: 1; the morphology control agent is a mixture of sodium nitrate, nitric acid, ammonium formate and ammonium citrate salt, and the mass ratio of the morphology control agent to the ammonium citrate salt is 20:10:2: 1;

step three, adopting a constant-current electrolysis method, wherein the cathode is a titanium plate, the anode is a coarse silver plate, the inter-polar distance is 20cm, and the current is 20A/dm 2; after electrolyzing for a certain time, brushing silver powder separated out from the titanium cathode plate by using a brush, wherein the brushing period is 50 s;

step four, sending the silver powder obtained in the step three into a Buchner funnel, and cleaning the silver powder with deionized water;

step five, feeding the material obtained in the step four into a centrifuge for solid-liquid separation to obtain silver powder;

and sixthly, putting the silver powder obtained in the fifth step into a dryer to dry the silver powder for 1h, and obtaining the rod-shaped silver powder with the surface having the flaky laminated structure after drying.

By comparing the six preparation methods of the rod-shaped silver powder with the flaky laminated structure on the surface, the rod-shaped silver powder with the flaky laminated structure on the surface can be prepared by the six preparation methods of the rod-shaped silver powder with the flaky laminated structure on the surface.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.