KR20120064997A - Method for manufacturing ag nano-wire - Google Patents

Abstract

PURPOSE: A manufacturing method of a silver nano-wire is provided to manufacture a nano-silver wire in a uniformed size by using AAO(Anodic Aluminum Oxide) and nano-ink and to minimize influence of the fabrication condition of the nano-silver wire. CONSTITUTION: A manufacturing method of a nano-silver wire comprises the following steps: eliminating a barrier layer of AA0(Anodic Aluminum Oxide)(s100); adding the aluminum anodic oxide into nano-silver ink and forming a vacuum condition(s102); heat treating the aluminum anodic oxide at 200-400 deg. Celsius(s106); and dissolving the heat treated aluminum anodic oxide(s108). The aluminum anodic oxide is formed in a template form. In the elimination step, the aluminum anodic oxide is dipped in mixed solution of deionized water and NaOH. The nano-silver ink includes nano-silver particles having particle size of less than 10 nano meters.

Description

Method for manufacturing silver nanowires {Method for manufacturing Ag nano-wire}

The present invention relates to a method for manufacturing silver nanowires, and more particularly, to a method for manufacturing silver nanowires using silver nano ink containing aluminum anodic oxide (AA0) and silver nanoparticles. will be.

Nanotechnology is a microfabrication technology that requires nanometer-scale precision, meaning one billionth.

Nanotechnology is a technology that creates materials, devices, or systems that exhibit new or improved physical, chemical, and biological properties by manipulating, analyzing, and controlling them in the nanometer-sized range.

In particular, nano-materials having a one-dimensional nanostructure have a unique quantum characteristic, and thus, there is a wide range of applications.

Nanoparticles, on the other hand, are nanotubes that are hollow in size depending on their shape, such as nano-tubes, rod-shaped nanorods, and nanorods, which do not have a constant growth direction. -wire), nanorods are grown in the same direction as nanorods, but are tapered toward the ends, and nano-powders, which are nano-sized powders.

Silver nanoparticles have recently been applied to various fields as nanoparticle materials.

Silver nanoparticles are relatively harmless to the human body, and silver nanoparticles have been used in various fields due to effects such as sterilization, removal of harmful components, and deodorization.

Among the silver nanoparticles, a conventional method of manufacturing silver nanowires having a rod shape but not having a constant growth direction will be described.

Among the conventional methods for producing silver nanowires, there is a method of synthesis through a solvent such as silver nitrate (AgNO 3: silver nitrate) and ethanol and heat treatment thereof.

However, the manufacturing method of such silver nanowires has a problem in that the size of the produced silver nanowires is very unevenly synthesized.

As another method of manufacturing a conventional silver nanowire, there is also a method using aluminum anodic aluminum oxide (AA0).

The conventional method using aluminum anodic oxide is dropping or immersing liquid silver nitrate in aluminum anodic oxide to allow natural ingress, followed by heat treatment (calcination), and then removing aluminum anodic oxide to recover silver nanowires. It is a method of manufacturing the wire.

However, in such a method, the quality of the silver nanowires is very sensitive to the concentration of silver nitrate and the heat treatment conditions, so there is a problem in reproducibility.

Another conventional method for producing silver nanowires using aluminum anodic oxide is to introduce silver particles into aluminum anodic oxide using electrodeposition, which is characterized by constant current deposition, constant voltage deposition, alternating current deposition, pulse Vapor deposition, cyclic voltammetry, and the like are widely used.

However, in the case of the method using the electro-deposition, it is very difficult to control the process parameters, and the pore size of 180 nm to 400 nm or more is required for the aluminum anode oxide in order to fill the aluminum anode oxide well. The size of the nanowires is also increased and there is a problem in that the field that can be used is limited.

In order to solve the conventional problems as described above, the present invention proposes a method for producing silver nanorods which is more uniform and has a minimal influence on the manufacturing conditions of silver nanowires.

It is possible to produce silver nanowires having a smaller size, and therefore, to propose a method of manufacturing silver nanowires, which is not limited in the field in which silver nanowires can be used.

Still other objects of the present invention will be readily understood through the following description of the embodiments.

In order to achieve the object as described above, according to an aspect of the present invention there is provided a method for producing a silver nanowire.

According to one preferred embodiment of the present invention, a method of manufacturing Ag nano-wire, comprising: removing a barrier layer of aluminum anode (AA0); Injecting the aluminum anode oxide from which the barrier layer is removed into a silver nano ink and forming a vacuum state; Heat-treating the aluminum anodic oxide which was introduced into the silver nano ink and formed a vacuum state; And dissolving the heat-treated aluminum anode oxide is provided.

The aluminum anode oxide may be formed in the form of a template.

The aluminum anode oxide is, by immersing aluminum in acetone, ultrasonic cleaning and drying; Immersing the dried aluminum in an electrolyte solution in which perchloric acid (HClO 4) and ethanol (C 2 H 5 OH) are mixed at a volume ratio of 1: 3, respectively, and then applying a constant voltage of 10 to 40 V; Applying a constant voltage of 20 to 50 V by immersing aluminum to which the constant voltage of 10 to 40 V was applied in oxalic acid; Immersing the aluminum applied with the constant voltage of 20 to 50 V in a solution in which chromic acid, phosphoric acid, and deionized water are mixed; And immersing the immersed aluminum in an electrolyte solution in which the perchloric acid (HClO 4) and the ethanol (C 2 H 5 OH) are mixed at a volume ratio of 1: 3, respectively, and then applying a constant voltage of 10 to 40 V. And immersing aluminum to which the constant voltage of 10 to 40 V is applied to the mixed solution of copper chloride and hydrochloric acid.

Removing the barrier layer of the aluminum anode oxide may be performed by immersing the aluminum anode oxide in a mixed solution of sodium hydroxide (NaOH) and deionized water (DI water).

The silver nano ink may be silver nano ink including silver nano particles having a size of 10 nm or less.

The step of heat-treating the aluminum anodic oxide, which was added to the silver nano ink and formed a vacuum state, may be performed within a temperature range of 200 to 400 ° C.

Dissolving the heat treated aluminum anode oxide may be performed by immersing the aluminum anode oxide for 5 to 24 hours in a solution of 60 ° C mixed with 9 g of chromic acid, 30 ml of phosphoric acid, 500 ml of ultrapure water.

After performing the step of dissolving the heat-treated aluminum anode oxide, the step of recovering the silver nanowires from the dissolved aluminum anode oxide may be further performed.

The recovering of the silver nanowires from the dissolved aluminum anode oxide may be performed by repeatedly filtering and drying the dissolved aluminum anode oxide on filter paper.

As described above, according to the method for producing silver nanowires according to the present invention, silver nanowires having a more uniform size can be produced, and there is an advantage that the production conditions of silver nanowires are minimally affected. .

And it is possible to manufacture a silver nanowire having a smaller size, and thus there is an advantage that the field where the silver nanowires can be used is not limited.

1 is a flow chart showing the order in which the manufacturing method of the silver nanowires according to an embodiment of the present invention.
FIG. 2 is a diagram of an electron microscope image of the cross section of the aluminum anodized oxide after the silver nano ink is introduced into the aluminum anodized oxide according to the method of manufacturing the silver nanowire according to the preferred embodiment of the present invention before the heat treatment is performed. FIG.
FIG. 3 is a diagram illustrating an electron microscope image of a cross section of aluminum anode oxide after heat treatment is performed after the silver nano ink is introduced into the aluminum anode oxide according to the manufacturing method of the silver nanowire according to the preferred embodiment of the present invention.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for like elements in describing each drawing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be.

On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art.

Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be denoted by the same reference numerals regardless of the reference numerals and redundant description thereof will be omitted.

First, with reference to FIG. 1, the order in which the manufacturing method of the silver nanowire according to the exemplary embodiment of the present invention is made will be described.

FIG. 1 is a flowchart illustrating a procedure of manufacturing a silver nanowire according to an exemplary embodiment of the present invention.

As shown in FIG. 1, in the method of manufacturing the silver nanorods according to the preferred embodiment of the present invention, first, a barrier layer of aluminum anode oxide (AA0) is removed (S100).

The barrier layer is also referred to as an unlayered layer. In general, when a metal and a semiconductor are brought into contact with each other to pass a current, resistance may vary depending on the direction of the current, and a high resistance layer is formed on the semiconductor side.

This barrier layer acts to block electrons or holes, which are carriers of current, so that they cannot easily flow to one side.

The removal of the barrier layer is intended to prevent the growth direction of the silver nanowires from being uniform since the growth direction of the silver nanowires is characterized in that the growth direction is not constant unlike the silver nanorods.

The method of removing the barrier layer of the aluminum anode oxide may be performed by immersing and dissolving in a mixed solution of sodium hydroxide (NaOH) and deionized water (DI water).

Meanwhile, the aluminum anode oxide used in the present invention may preferably be a template having a shape of a thin plate of aluminum anode oxide having nano-sized pores.

For example, the following method may be used as a method of manufacturing a template of aluminum anode oxide having such nano-sized pores.

First, aluminum is immersed in acetone, and then ultrasonically cleaned for 5 to 30 minutes, followed by washing with deionized water.

Then, electropolishing is performed.

In electrolytic polishing, aluminum is deposited in an electrolyte mixture of perchloric acid and ethanol at a ratio of 1: 3 to dissipate heat generated by reaction under constant voltage of 10 to 40 V and constant current of 0.2 to 0.8 A. It can be stirred through an agitation device, externally or internally.

This electropolishing time is preferably 5 to 30 minutes, the electrolyte temperature may be made in the range of -5 to 50 ℃.

The electrolytically polished specimens were taken out, washed, dried, and then mixed with oxalic acid and deionized water to form 3 mol of oxalic acid, followed by primary anodic oxidation.

In this case, the constant voltage is preferably 20 to 50V, the constant current is 5 to 20Ma, the processing time may be performed in the range of 1 to 48 hours.

In order to optimize the alignment and shape uniformity of the nano pores, alumina, which is aluminum oxide produced during the primary anodic oxidation, is removed.

The removal of the alumina is immersed in the mixed solution of chromic acid and phosphoric acid, wherein the temperature is 20 to 60 ℃, the treatment time is preferably carried out in the range of 5 to 24 hours.

On the other hand, when the removal of alumina is completed, a secondary anodic oxidation reaction is performed under the same conditions as the primary anodic oxidation reaction.

Upon completion of the secondary anodic oxidation reaction, aluminum is selectively dissolved by removing aluminum since the aluminum anodized oxide having a nano-sized pore and the aluminum part are mixed.

The aluminum may be removed using a mixed solution of copper chloride and hydrochloric acid, and the treatment temperature may be performed in a range of 20 to 30 ° C. and a treatment time of 0.5 to 1 hour.

The template of the aluminum anode oxide prepared in this way has a very uniform pore size and can control the pore size by adjusting the treatment time and other process conditions.

On the other hand, the production of a template of aluminum anode oxide having nano-sized pores is not limited to this method, and there is no limitation as long as it is a method capable of manufacturing aluminum anode oxide having nano-sized pores.

The aluminum anode oxide from which the barrier layer has been removed is loaded into the silver nano ink (S102).

Next, the aluminum anode oxide charged in the silver nano ink is put in a device such as a vacuum chamber to make a vacuum state (S104).

In other words, the aluminum anodized oxide in which the barrier layer is removed is introduced into the silver nano ink to form a vacuum state.

In this way, the air in the nano-sized micropores of the aluminum anodic oxide escapes and the silver nanoparticles contained in the silver nano ink enter the micropores of the aluminum anodic oxide.

The silver nano ink is an ink containing silver nano particles having a particle size of 10 nm or less, and is widely available as a ready-made product, and the present invention uses such silver nano ink which can be easily purchased on the market.

Thus, the aluminum anode oxide of silver nanoparticles of the silver nano ink introduced into the micropores is heated (S106).

The heating of the aluminum anode oxide into which the silver nano ink is introduced, that is, the heat treatment, may be performed by placing the aluminum anode oxide on a hot plate heated to a temperature range of 200 to 400 ° C.

Through this heating process, the silver nanoparticles are connected to each other to generate silver nanowires.

On the other hand, when the heating of the aluminum anode oxide is completed, the aluminum anode oxide is dissolved to recover the silver nanowires (S104).

First, dissolution of the aluminum anode oxide is preferably performed by immersing a solution containing 9 g of chromic acid, 30 ml of phosphoric acid, and 500 ml of ultrapure water at 60 ° C. in a suitable time depending on the thickness of the aluminum anode oxide in a range of 5 to 24 hours. But it is not limited thereto.

In addition, the method of recovering only the silver nanowires from the dissolved aluminum anode oxide may be recovered by dissolving the aluminum anode oxide after heating and filtering and drying the filter paper several times on a conventional chemical experiment filter, but the present invention is not limited thereto. .

When the silver nanowires are manufactured using the silver nano ink and the aluminum anode oxide, the silver nanowires may be manufactured through a simpler and simpler process.

In particular, by using silver nano ink widely used as a ready-made product, it is possible to manufacture silver nanowires more easily, and it is possible to manufacture silver nanowires under conditions that are not complicated and sensitive processing conditions as in the prior art.

Hereinafter, the shape of the silver nanowires manufactured by the method for manufacturing the silver nanowires according to the preferred embodiment of the present invention will be described with reference to FIGS. 2 and 3.

First, FIG. 2 is a diagram illustrating an electron microscope image of a cross section of aluminum anodic oxide before heat treatment after injecting silver nano ink into aluminum anodic oxide according to a method of manufacturing silver nanowires according to a preferred embodiment of the present invention. to be.

As also shown in the figure taken with the electron microscope of FIG. 2, the aluminum anode oxide used for this invention has the fine pore 220. As shown in FIG.

When the aluminum anodic oxide is charged into a silver nano ink having silver nanoparticles 210 having a size of 10 nm and placed in a vacuum chamber or the like to create a vacuum state, the silver nano particles 210 of the silver nano ink are formed of aluminum anodic oxide. It will be drawn into the fine pores 220.

On the other hand, the fine pores 220 of the aluminum anode oxide generally has a size of about 70 nm, whereas the silver nanoparticles 210 included in the silver nano ink have a size of 10 nm or less, as shown in FIG. 2. Before the heat treatment of the aluminum anode oxide, silver nanoparticles 210 having a size of 10 nm are present in the minute pores 220 of the aluminum anode oxide.

When the heat treatment is performed in such a state, as shown in FIG. 3, silver nanoparticles 210 having a size of 10 nm or less are connected to each other to form a silver nanowire 200.

The silver nanowires 200 formed as described above have a size of 70 nm or less, which is the size of the micropores 220 of the aluminum anode oxide.

In general, silver nanowires have a rod shape, but unlike the silver nanorods, the growth direction is not constant, and the silver nanowires formed by the present invention may be made of silver nanowires in which the growth direction is not constant. This is because the barrier layer is removed from the aluminum anode oxide.

Therefore, according to the method for manufacturing silver nanowires according to the present invention, it is possible to easily manufacture a plurality of silver nanowires having a size of about 70 nm, which is the size of the micropores of the aluminum anode oxide.

In addition, since the silver nanowires are formed by the micropores of the aluminum anode oxide, the silver nanowires may be more uniformly formed.

In addition, since silver nanowires are formed through heat treatment using aluminum anode oxide, which is widely used in the related art, the formation of silver nanowires is not significantly affected by manufacturing conditions for the production of silver nanowires.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art will be able to make various modifications, changes, and additions within the spirit and scope of the present invention. Additions should be considered to be within the scope of the following claims.

200: silver nanoparticles 210: silver nanowires
220: micropores of aluminum anode oxide

Claims (9)

In the manufacturing method of silver nano-wire (Ag nano-wire),
Removing a barrier layer of aluminum anodic aluminum oxide (AA0);
Injecting the aluminum anode oxide from which the barrier layer is removed into a silver nano ink and forming a vacuum state;
Heat-treating the aluminum anodic oxide which was introduced into the silver nano ink and formed a vacuum state; And
And dissolving the heat treated aluminum anodic oxide.
The method of claim 1,
The aluminum anode oxide is a method of manufacturing a silver nano wire, characterized in that formed in the form of a template (template).
The method of claim 1,
The aluminum anode oxide is,
Immersing aluminum in acetone to perform ultrasonic cleaning and then drying;
Immersing the dried aluminum in an electrolyte solution in which perchloric acid (HClO 4) and ethanol (C 2 H 5 OH) are mixed at a volume ratio of 1: 3, respectively, and then applying a constant voltage of 10 to 40 V;
Applying a constant voltage of 20 to 50 V by immersing aluminum to which the constant voltage of 10 to 40 V was applied in oxalic acid;
Immersing the aluminum applied with the constant voltage of 20 to 50 V in a solution in which chromic acid, phosphoric acid, and deionized water are mixed;
Immersing the immersed aluminum in an electrolyte solution in which the perchloric acid (HClO 4) and ethanol (C 2 H 5 OH) are mixed in a volume ratio of 1: 3, respectively, and then applying a constant voltage of 10 to 40 V; And
A method for producing silver nanowires, characterized in that the aluminum anodized oxide produced by immersing the aluminum applied a constant voltage of 10 to 40V in a mixed solution of copper chloride and hydrochloric acid.
The method of claim 1,
Removing the barrier layer of the aluminum anode oxide is characterized in that is performed by immersing the aluminum anode oxide in a mixed solution of sodium hydroxide (NaOH: sodium hydroxide) and DI water (DI water: deionized water) Method for producing silver nanowires.
The method of claim 1,
The silver nano ink is a silver nano-wire manufacturing method, characterized in that the silver nano ink containing silver nanoparticles of 10nm size or less.
The method of claim 1,
The step of heat-treating the aluminum anodic oxide which was added to the silver nano ink and formed a vacuum state, the manufacturing method of the silver nanowires, characterized in that carried out within a temperature range of 200 to 400 ℃.
The method of claim 1,
Dissolving the heat treated aluminum anode oxide,
9 g of chromic acid, 30 ml of phosphoric acid, 500 ml of ultrapure water is prepared by dipping the aluminum anode oxide for 5 to 24 hours in a solution of 60 ° C.
The method of claim 1,
After the step of dissolving the heat treatment the aluminum anode oxide,
The method for producing silver nanowires, characterized in that to perform the step of recovering the silver nanowires from the dissolved aluminum anode oxide.
The method of claim 8,
Recovering the silver nanowires from the dissolved aluminum anode oxide,
Method of producing a silver nanowires, characterized in that by repeating the process of filtering and drying the dissolved aluminum anodic oxide on the filter paper.

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