KR101130161B1 - 3-dimension nano structure and manufacturing method thereof - Google Patents

Abstract

Three-dimensional nanostructures are disclosed. 3D nanostructure according to an embodiment of the present invention is a step of etching the upper region of the current collector in the form of a three-dimensional nanostructure, forming a metal layer on the etched current collector, and a metal on the current collector formed metal layer Forming a compound layer. Accordingly, it is possible to provide a three-dimensional nanostructure easy to penetrate the electrolyte.

Current collector, electrode, sulfidation, nano structure

Description

3-dimensional nano structure and manufacturing method thereof

The present invention relates to a three-dimensional nanostructure and a method for manufacturing the same, and more particularly to a three-dimensional nanostructure and a method of manufacturing the same by etching the current collector.

Batteries can be classified into disposable primary batteries and rechargeable batteries that can be charged many times. Among these, the rechargeable battery has been popularized as an essential energy source for portable electronic devices such as laptops, camcorders, and mobile phones due to its ability to be charged many times.

The secondary battery is composed of a negative electrode, a positive electrode, an electrolyte, and a current collector. In the positive electrode, a reduction reaction occurs by electrons generated at the negative electrode, and the current collector supplies electrons generated from the negative electrode to the positive electrode active material when the battery is discharged, or electrons supplied from the positive electrode to the negative electrode active material at the time of charging. do.

In recent years, secondary batteries have been changed in form and size depending on their purpose, ranging from large-capacity batteries for power storage, medium-size batteries applied to transportation vehicles, and small batteries used as power sources for portable devices. It is becoming a trend.

However, the current collector used in the conventional variable battery generates plastic deformation as the shape of the battery changes. In the case of using a conventional current collector, if the shape is repeatedly changed, plastic deformation occurs and work hardening occurs, and as a result, the current collector is hardened and broken.

In order to solve such a problem, a battery current collector-electrode integrated device for which a alloy having shape memory characteristics is used as a current collector and Ti and Ni sulfides are formed on the surface of the current collector as an electrode active material has been devised.

Conventional battery electrodes utilize a process of applying a powder to an electrode active material and a conductive agent in a slurry form using a binder and a solvent capable of dissolving it, and then applying the same to a current collector. For this reason, the conventional battery electrode has a thick thickness of about 20 to 50 µm, and a problem of adhesion strength between the current collector and the electrode active material layer occurs.

In addition, the binder used to bond the electrode active material and the conductive agent to each other has a low electrical conductivity, which is a factor of increasing the resistance of the electrode. Moreover, the electrode prepared through the application and drying of the slurry has a small pore size and the surface pores are not easily connected with the inside, so that penetration of the electrolyte solution is not easy.

SUMMARY OF THE INVENTION An object of the present invention is to provide a current collector-electrode integrated device and a method of manufacturing the electrode active material which can be directly formed on the current collector by using electroless plating and sulfidation, and can secure the penetration region of the electrolyte solution.

Method for manufacturing a three-dimensional nanostructure according to an embodiment of the present invention for achieving the above object, the step of etching the upper region of the current collector in the form of a three-dimensional nanostructure, forming a metal layer on the etched current collector And forming a metal compound layer on the current collector on which the metal layer is formed.

The forming of the metal layer may include forming a metal layer on the current collector etched by using at least one of an electroless plating method, an electrolytic plating method, a sputtering method, and a vacuum deposition method.

Here, the metal compound layer may be a metal sulfide layer formed by sulfiding a current collector on which the metal layer is formed.

Alternatively, the metal compound layer may be formed through an oxidative heat treatment or may be a metal oxide layer formed by heat treating a precursor for forming an oxide layer.

In addition, the metal sulfide layer or the coating layer for improving the conductivity formed on the metal oxide layer may be further included.

In addition, the upper region of the current collector etched in the 3D nano form is formed of a plurality of nano structures, each nano structure may be capable of shape control.

On the other hand, the three-dimensional nanostructure according to an embodiment of the present invention, the upper region of the current collector etched in the form of a three-dimensional nanostructure, the metal layer formed on the etched current collector, and the current collector on the metal layer It includes a metal compound layer formed.

Here, the metal compound layer may be a metal sulfide layer formed by sulfiding a current collector on which the metal layer is formed.

Alternatively, the metal compound layer may be formed by an oxidizing heat treatment, or may be a metal oxide layer formed by heat treating a precursor for forming an oxide layer.

In addition, it may further include a coating layer for improving the conductivity formed on the metal sulfide layer or the oxide layer.

The upper region of the current collector etched in the 3D nano form may be formed of a plurality of nano structures, and each nano structure may be shape-controlled.

As a result, since the electrode active material is directly formed on the current collector, a low electrical conductivity does not require a binder and a conductive agent to increase the resistance of the electrode, and an inexpensive manufacturing process is possible.

In addition, since many pores are formed in the active material layer due to evaporation of ammonia gas and moisture during the heat treatment process of sulfidation, it is very easy to secure the penetration region of the electrolyte solution. As the electrolyte easily penetrates, it is easy to secure a path through which lithium ions can move, so that the reaction between the lithium ions and the electrode active material is more efficient.

Furthermore, the thickness of the active material layer of the electrode can be formed thinner, whereby the electrons move easily during battery reaction, thereby improving the performance of the battery.

In addition, it is possible to improve the performance of the energy converter using the three-dimensional nanostructures that facilitate electrolyte penetration.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the present invention.

1A through 1C are cross-sectional views illustrating a process of manufacturing a current collector-electrode integrated device according to an embodiment of the present invention.

1A is a cross-sectional view of the current collector 110 used in the current collector-electrode integrated device. As the current collector 10, a conductive material should be used. In the present embodiment, as the current collector 10, a copper plate having a thickness of 20 μm may be used.

1B is a cross-sectional view of the plating metal layer 20 formed on the current collector 10. The plating metal layer 20 is formed by electroless nickel plating. In this embodiment, the electroless plating is used as a method for forming nickel (Ni) and nickel phosphide (Ni ₃ P) plating on the current collector 10. In addition, as a raw material of nickel and nickel phosphide plating, nickel chloride (NiCl ₂ 6H ₂ O), sodium hypophosphite (NaPO ₂ H ₂ H ₂ O), sodium citrate (NaH ₃ C ₆ H ₅ O ₇ 2H) ₂ O), and ammonium chloride (NH ₄ Cl).

Electroless plating is a method of depositing metal on the surface of an object by self-catalytic reduction of metal ions in an aqueous metal salt solution by a reducing agent without receiving electrical energy from the outside, also called chemical plating or self-catalyst plating.

Prior to forming the plated metal layer 20 on the current collector 10, in order to form the plated metal layer 20 only on one side of the current collector 10, the plated metal layer 20 is not formed on the other side. It is preferable to face the copper plates of the same size as the current collector 10.

In order to form the plated metal layer 20, a plating solution is first prepared. In this embodiment, the plating solution is added to the raw material of nickel and nickel phosphide plating, that is, nickel chloride, sodium hypophosphite, sodium citrate, and ammonium chloride in distilled water, so that the temperature of this solution reaches a predetermined plating temperature. When the temperature is raised and the solution reaches a predetermined plating temperature, it is prepared by adjusting to a strong base (pH9) atmosphere using sodium hydroxide. Here, the predetermined plating temperature may be 90 degrees.

At this time, the raw material of nickel and nickel phosphide plating may be used in the amount of nickel chloride 45g / l, sodium hypophosphite 11g / l, sodium citrate 100g / l, and ammonium chloride 50g / 1 based on 1L of distilled water.

When the preparation of the plating solution is completed, the current collector 10 is immersed in the plating solution for a predetermined plating time. At this time, the current collector 10 may be in a state of facing the copper plate of the same size on the other side in order to form the plated metal layer 20 on one side. Here, the predetermined plating time may be 30 minutes.

After the predetermined plating time, for example, 30 minutes has elapsed by immersing the current collector 10 in the plating solution, the plated metal layer 20 is formed on the current collector 10 in the form as shown in FIG. 1B. As a result, one side of the current collector 10 is plated with nickel and nickel phosphide. Referring to FIG. 1B, spherical particles having a size of 2 to 3 μm are formed on the surface of the plated metal layer 20 formed on the current collector 10.

When forming a plated metal layer on the current collector 10 using electroless plating, zinc (Zn), iron (Fe), cadmium (Cd), cobalt (Co), nickel (Ni), tin (Sn), and lead Materials such as (Pb), copper (Cu), and silver (Ag) may also be used as raw materials.

FIG. 1C is a cross-sectional view of a metal sulfide layer 30 formed by sulfiding a current collector 10 having a plated metal layer 20 formed thereon. In this embodiment, as the raw material for the sulfidation treatment, ammonium polysulfide ((NH ₄ ) ₂ S _x ) and sodium sulfide (Na ₂ S) may be used.

In order to sulfide the current collector 10 on which the plated metal layer 20 is formed, first, a sulfidation solution is prepared. The sulfided solution can be prepared by adding ammonium polysulfide and sodium sulfide to distilled water to heat up the solution until it reaches a predetermined sulfiding temperature. In this case, the predetermined sulfidation temperature may be 80 degrees. In addition, during the temperature raising process of the sulfiding solution preparation process, it is preferable to stir at a predetermined rate until the sodium sulfide is completely dissolved. In preparing the sulfided solution, 200 ml of ammonium polysulfide and 0.47 g of sodium sulfide may be used based on 250 ml of distilled water.

When manufacturing the sulfided solution is completed, the sulfided solution is applied to the current collector 10 on which the plated metal layer 20 is formed, dried for a predetermined time, and then heated at a predetermined temperature, for example, 60 degrees for a predetermined time. .

In this way, the sulfidation process is completed when a predetermined time has elapsed while the sulfiding solution is applied onto the current collector 10 on which the plated metal layer 20 is formed and heat is applied at a predetermined temperature. When the sulfidation is completed, a current collector-electrode integrated element of the type shown in 1c is obtained.

As shown in FIG. 1C, as the ammonia gas (NH ₃ ) evaporates due to heat treatment in the process of sulfiding the current collector 10 having the plated metal layer 20 formed thereon, the surface of the current collector-electrode integrated device has a large amount. Pores are formed. The pores formed as described above have an effect of facilitating the penetration of the liquid electrolyte when the current collector-electrode integrated device is applied to the lithium secondary battery.

2A to 2C are views showing the surface shape of FIGS. 1A to 1C.

FIG. 2A shows the shape when the surface of the current collector 10 shown in FIG. 1A is observed using a scanning electron microscope. As shown in the drawing, the surface of the current collector 10 may have a curvature that appears when the current collector 10 is processed. However, the curvature of the current collector 10 surface does not affect the fabrication of the current collector-electrode integrated device.

FIG. 2B shows the shape when the surface of the current collector 10 on which the plated metal layer 20 shown in FIG. 1B is formed is observed using a scanning electron microscope. The particles shown in the plated metal layer 20 of FIG. 2B correspond to the spherical particles shown in FIG. 1B. These spherical particles are nickel phosphide (Ni ₃ P or Ni ₂ P). 2B, it can be seen that the curvature of the surface of the current collector 10 shown in FIG. 2A has disappeared.

FIG. 2C shows the shape when the surface of the current collector 10 on which the metal sulfide layer 30 shown in FIG. 1C is formed is observed using a scanning electron microscope. When the current collector 10 in which the plated metal layer 20 of FIG. 2 is formed is sulfided, many pores are formed on the surface while ammonia gas and moisture are evaporated during the heat treatment during the sulfidation process. At this time, the penetration region of the electrolyte is secured by pores formed by evaporation of ammonia gas and moisture.

3 is a graph showing charge / discharge according to a constant current test of a current collector-electrode integrated device according to an embodiment of the present invention.

FIG. 3 shows the current collector-electrode integrated device laminated with a liquid electrolyte and lithium ions in a stainless cell to construct a battery, and the battery was subjected to a constant current test in a voltage range of 0.8 to 2.8 V with a current of 50 mA. The charge / discharge curve at the time is shown. In the graph of FIG. 3, A is the charge / discharge curve in the first cycle, and B is the charge / discharge curve in the second cycle.

As shown in FIG. 3, the current collector-electrode integrated device exhibited a reaction section of 1.98 V and 1.3 V during a discharge process, and a reaction section at 1.9 V and 2.45 V during a charging process. 1.98V of the discharge process and 2.45V of the charge process are oxidation and reduction processes of nickel phosphide, and 1.3V of the discharge process and 1.9V of charging process are oxidation and reduction processes of nickel sulfide.

4 is a graph showing the discharge capacity according to the number of cycles of the current collector-electrode integrated device according to an embodiment of the present invention.

FIG. 4 is a graph (C) showing discharge capacity according to cycle number of a current collector-electrode integrated device under the same conditions as in FIG. 3. As the number of cycles increases, the discharge capacity decreases.

5 is a flowchart illustrating a method of manufacturing a current collector-electrode integrated device according to an embodiment of the present invention.

To prepare a plating solution for electroless plating (S100). Here, the plating solution is a solution containing nickel chloride, sodium hypophosphite, sodium citrate, and ammonium chloride in distilled water when the solution reaches a predetermined plating temperature, for example, 90 degrees. It may be a solution prepared by adjusting.

When the preparation of the plating solution is completed, the current collector 10 shown in FIGS. 1A and 2A is immersed in the plating solution based on a predetermined plating time, for example, for 30 minutes (S110). At this time, only one side of the current collector 10 should be plated.

After the predetermined plating time passes after the current collector 10 is immersed in the plating solution, the plated metal layer 20 is formed on one surface of the current collector 10. The current collector 10 having the plated metal layer 20 formed thereon is washed with distilled water, and the residual water is removed through a drying process (S120).

When the formation of the plating metal layer 20 using the electroless plating is completed, a sulfidation solution for sulfidation is prepared (S130). Here, the sulfidation solution may be a solution in which the solution in which ammonium polysulfide and sodium sulfide are added to distilled water is heated to reach a predetermined sulfation temperature, for example, 80 degrees. At this time, sodium sulfide, which is one of the raw materials of the sulfidation solution, must be completely dissolved.

When manufacturing of the sulfided solution is completed, the sulfided solution prepared previously is coated on the current collector 10 on which the plated metal layer 20 is formed, dried at room temperature for a predetermined time, for example, for 3 hours, and then at a predetermined temperature. For example, the sulfurization treatment is carried out for 12 hours at 60 degrees (S140).

After the sulfidation is completed, the metal sulfide layer 30 is formed on the current collector 10. This is washed with distilled water, and removes residual moisture through the drying process (S150).

Steps S100 to S120 correspond to a procedure of forming the plating metal layer 20 using electroless plating, and steps S130 to S150 correspond to a procedure of forming the metal sulfide layer 30 using sulfiding. The current collector-electrode integrated device is manufactured by such a procedure.

Through the above process and the active material layer of the electrode is formed. As described above, since the active material layer of the electrode formed through the electroless plating and the sulfidation process is formed thinner than the conventional electrode, the electrons can be easily moved during the battery reaction, thereby improving the performance of the battery.

The current collector-electrode integrated device may be laminated with a liquid electrolyte and lithium ions in a cell made of stainless steel to constitute a battery. When the battery is constructed using the current collector-electrode integrated device, the reaction area of lithium ions is increased due to the easy penetration of the liquid electrolyte.

6A through 6F are cross-sectional views illustrating a process of manufacturing a 3D nanostructure according to another embodiment of the present invention. Meanwhile, for convenience of description, detailed descriptions of parts overlapping with the description of FIGS. 1 to 5 will be omitted.

6A is a cross-sectional view of the current collector 110 used in the three-dimensional structure.

The current collector 110 serves to create a flow of electrons between the electrode active material and the battery terminal, and may be used without particular limitation as long as it has high conductivity without causing chemical change in the battery.

The current collector 110 is made of, for example, copper, nickel, stainless steel, titanium, aluminum, carbon-coated aluminum, nickel foam, copper foam, a polymer substrate coated with a conductive metal, and combinations thereof. One selected from the group may be used, and in some cases, the material may be processed into a foam type, a mesh type, a conductive material coating type, a perforated type, etc., but is not limited thereto. Alternatively, a material obtained by coating at least one surface of the above materials with another material may be used.

FIG. 6B is a cross-sectional view of a state in which a patterned mask is coated to etch the top of the current collector 110 into a three-dimensional nanostructure.

Hereinafter, an etching process for etching the upper part of the current collector 110 to form a 3D nanostructure will be described.

The etching process is classified into wet etching and dry etching according to the method. The wet etching is exposed using an acid-based chemical that reacts with a metal to corrode. It means melting the part (without PR pattern), and dry etching means forming a pattern by accelerating ions to remove material on exposed areas.

In addition, each etching method is divided into selective etching and nonselective etching. Selective etching refers to etching by reacting only on a layer of a surface without affecting another layer among layers. Selective etching refers to etching multiple layers simultaneously by reacting with other layers.

Selective etching in wet etching is made possible by the use of a combination of several chemicals to make an etchant to react only with specific materials, and in the case of dry etching, by injecting reactive gases that only react with specific materials. Especially in the case of dry etching, sputtering etching using magnetron, such as ion beam etching (IBE) or sputtering using only ion acceleration, is non-selective etching, and reactive gas is used for ion acceleration. Reactive ion etching (RIE) using is a selective etching.

In the case of etching the current collector 110 according to the present invention, both wet etching and dry etching may be used, and among them, selective etching may be used.

Hereinafter, a method of forming a mask pattern used for etching will be briefly described.

The pattern of the mask (not shown) may be formed by a lithography process.

Lithography refers to a process of changing a mask using photons, electrons, ions, etc. that have passed through the mask, and chemically treating the denatured parts to create a desired pattern. The lithography process can be divided into three stages. First, a photosensitive polymer material is uniformly applied to a material on which a pattern is to be formed. Thereafter, photons, electrons, ions, and the like having passed through a mask having a desired pattern engraved thereon are irradiated to the photosensitive film. Appropriate chemical processing (deeloping) to the modified photoresist film to form a pattern.

In some cases, more complex and detailed shapes can be produced by repeating lithography and processing several times.

Finally, as illustrated in FIG. 6B, the current collector 110 is etched using the mask 10 on which the pattern is formed. Here, the above-described dry etching or wet etching may be used as the etching method.

Subsequently, the mask remaining on the etched current collector is removed as shown in FIG. 6C. Here, as the mask removing liquid, organic solvents such as alcohols, glycols, ethers, esters, and ketones may be used.

6A to 6C, as illustrated in FIG. 6D, the current collector 110 having a top surface etched into a 3D nanostructure may be manufactured. Here, the plurality of nanostructures forming the three-dimensional nanostructure may be formed at a sufficient interval so that the electrolyte is interposed therebetween.

Here, the nanostructures may be mainly in the form of nano-tubes, nano-wires, nano-rods, nano-fibers, and in some cases, nano-rings ( It may be formed in the form of at least one of nano-ring, nano-horn (nano-horn).

Optionally, it is also possible to include nanoparticles having a diameter smaller than the void space between the nanostructures between the plurality of nanostructures (including inside the tube in the case of tubular shape). Here, the nanoparticles may be formed in a spherical shape, tubular shape, rod shape, tubular shape and the like.

FIG. 6F is a cross-sectional view of the metal layer 120 formed on the current collector 110 etched into the dimensional nanostructure. The metal layer 120 may be formed by a wet method such as an electroless plating method, an electroplating method, or a dry method such as sputtering or evaporation.

Here, electroless plating is a method in which metal ions in an aqueous metal salt solution are self-catalytically reduced by the force of a reducing agent to deposit metal on the surface of a workpiece without receiving electrical energy from the outside, also called chemical plating or self-catalyst plating. do. Electroplating is a method of covering an object's surface with a thin film of another metal using the principle of electrolysis, also called electroplating.

Sputtering is a method of attaching ions generated in plasma to a wafer using thin film equipment. Vacuum deposition is an electron beam or electric filament at high vacuum (5x10-5 to 1x10-7torr) to deposit a metal material. This method uses the principle of heating a boat to melt the metal on the boat and distilling it to condense onto the distilled metal cold wafer surface.

Here, carbon may be used as the metal layer 120. In this case, a metal may be plated on carbon and a metal sulfide (sulfide heat treatment) or metal oxide (oxidation heat treatment) layer may be formed as described below. According to this method, the area of contact between the metal sulfide or the metal oxide having low electrical conductivity and the carbon of the three-dimensional structure is increased, so that the electrode resistance is lower and the electrons can be supplied as compared to the structure in which the entire pillar is formed of the metal sulfide or metal oxide. The area is widened, and the performance of the battery can be improved.

In some cases, the metal layer 120 may include zinc (Zn), iron (Fe), cadmium (Cd), cobalt (Co), nickel (Ni), tin (Sn), lead (Pb), copper (Cu), And silver (Ag) and the like can be used.

6E is a cross-sectional view of the metal compound layer 130 formed on the current collector 110 having a three-dimensional nanostructure on which the metal layer 120 is plated.

Here, the metal compound layer 130 may be a metal sulfide or metal oxide 130 formed by sulfiding or oxidizing the current collector 110 having a nanostructure on which the metal layer 120 is plated.

The metal sulfide layer 130 may be formed by applying a sulfidation treatment solution to the current collector 110 having a three-dimensional nanostructure on which the metal layer 120 is plated, which is described above with reference to FIG. 1C, and thus, a detailed description thereof will be omitted.

The metal oxide layer 130 may be formed by an oxidizing heat treatment or a heat treatment using a precursor on the current collector 110 having a three-dimensional nanostructure on which the metal layer 120 is plated.

Meanwhile, in FIGS. 6C to 6F, a plurality of nano-rod shaped nanostructures are illustrated for convenience, but the number of nanostructures formed on the current collector 110 may vary depending on the interval at which the nanostructures are formed. . In addition, in FIG. 6B, the nanostructures are illustrated as being aligned in one direction, but may be irregularly arranged.

7A and 7B are cross-sectional views of three-dimensional nanostructures according to various embodiments of the present disclosure.

According to FIG. 7A, a three-dimensional nanostructure according to an embodiment of the present invention includes a current collector 110 and a sulfided metal layer 130.

The current collector 110 may be etched in the form of an upper region etched into a three-dimensional nanostructure, for example, by the method illustrated in FIGS. 6A to 6D.

The sulfided metal layer 130 is formed by sulfiding the metal layer 120 plated on the current collector 110 etched into a three-dimensional nanostructure to form an active material, for example, the method illustrated in FIGS. 6E and 6F. Can be processed.

According to FIG. 7B, a three-dimensional structure electrode according to another embodiment of the present invention includes a current collector 110, a sulfided metal layer 130, and a coating layer 140.

The coating layer 130 may be formed by coating and heat-treating a polymer, oil, sugars, liquid silicone, or the like.

8A to 8D are plan views illustrating a structure of a 3D nanostructure according to various embodiments of the present disclosure.

Referring to FIG. 8A, a plurality of nanostructures formed by etching the current collector 110 are formed at sufficient intervals so that an electrolyte may be interposed therebetween. Meanwhile, in FIG. 9A, although the nanostructures are formed to be aligned in both directions, the nanostructures may be irregularly arranged.

As described above, the nanostructures formed by etching the current collector 110 may be plated with a metal layer (not shown) and plated with a sulfided metal layer 130.

Referring to FIG. 8B, the plurality of nanostructures formed by etching the current collector 110 form groups, and the groups are formed at sufficient intervals so that an electrolyte may be interposed therebetween. In addition, the nanostructures constituting each group of nanostructures may be formed at a sufficient interval so that the electrolyte may be interposed therebetween.

As described above, the plurality of nanostructures formed by etching the current collector 110 may be plated with a metal layer (not shown) and plated with a sulfided metal layer 130.

8C and 8D, the plurality of nanostructures formed by etching the current collector 110 may have a cross section of a triangular shape and a rhombus shape. Or it may be formed to have another polygonal shape, the cross-sectional shape of each nanostructure is not limited thereto.

Meanwhile, in FIGS. 8A to 8D, the nanostructure 130 is formed in a vertical direction from the surface of the current collector 110 for convenience of description, but this is only an example, and the nanostructure 130 is formed. There is no limit to the direction. In addition, the nanostructures may be mainly in the form of nano-tubes, nano-wires, nano-rods, nano-fibers, and in some cases, nano-rings ( It may be formed in the form of at least one of nano-ring, nano-horn (nano-horn).

9A to 9D are cross-sectional views illustrating a configuration of an energy conversion device according to various embodiments of the present disclosure.

9A, the energy conversion device includes a first current collector 310, a first electrode unit 130, a second current collector 110 ′, a second electrode unit 130 ′, and an electrolyte unit 140. Include.

The first electrode unit 130 includes a plurality of nanostructures formed by etching an upper region of the first current collector 110.

The second electrode part 130 ′ is disposed to face the first electrode part 130, and includes a plurality of nano structures alternately disposed with the plurality of nano structures constituting the first electrode part 130.

Here, the nanostructures constituting the first electrode unit 130 and the second electrode unit 130 'are formed on the first current collector 110 and the second current collector 110' etched in the form of a three-dimensional nanostructure. The sulfided metal layer may be plated.

An electrolyte part 140 is interposed between the first electrode part 130 and the second electrode part 130 ′. Here, a liquid electrolyte or a solid electrolyte may be used for the electrolyte unit 140.

As the liquid electrolyte, for example, hydrochloric acid, sulfuric acid, nitric acid, sodium chloride, hydrogen chloride, copper sulfate, sodium sulfate, sodium hydroxide and the like can be used.

As the solid electrolyte, for example, ZrO 2, sodium β-alumina (NaAluO 17), AgI, RbAg 4 I 5, Nafion (trade name), an Asahi membrane, and the like can be used. However, the above materials are only one embodiment, and the materials used as the electrolyte are not limited thereto.

Meanwhile, in FIG. 9A, the nanostructures constituting the first electrode portion 130 and the second electrode portion 130 ′ are formed in the form of nanorods and are formed in a vertical direction from the surface of the substrate. And directions are not limited thereto.

9B is a cross-sectional view illustrating a configuration of an energy conversion device according to still another embodiment of the present invention.

According to FIG. 9B, the nanostructures constituting the first electrode unit 130 are formed in the form of nanotubes, and the nanostructures constituting the second electrode unit 130 ′ are formed in the form of nanowires.

In this case, the energy conversion device may be formed such that the nanowires constituting the second electrode portion 130 ′ are inserted into the nanotubes. In this case, the nanotubes constituting the first electrode 130 may have a diameter sufficient to allow the electrolyte 140 to penetrate therein even when the nanowires constituting the second electrode 130 are inserted. Can be.

Here, the nanostructures constituting the first electrode unit 130 and the second electrode unit 130 'are formed on the first current collector 110 and the second current collector 110' etched in the form of a three-dimensional nanostructure. The sulfided metal layer may be plated.

Of course, in this case, as shown in FIG. 9A, the nanotubes constituting the first electrode 130 and the nanowires constituting the second electrode 130 may be alternately arranged.

Meanwhile, the configuration of the energy conversion apparatus shown in FIGS. 9A and 9B may be a structure in which the three-dimensional nanostructures illustrated in FIGS. 8A, 8C, and 8D are disposed such that the nanostructures face each other.

Referring to FIG. 9C, the first electrode part 230 formed on the first current collector 210 may have a shape including a plurality of nanostructure groups composed of a plurality of nanostructures.

In addition, the second electrode part 230 ′ formed on the second current collector 210 ′ also has a shape including a plurality of nanostructure groups composed of a plurality of nanostructures.

Here, the nanostructures constituting the first electrode portion 230 and the second electrode portion 230 ′ are formed on the first current collector 210 and the second current collector 210 etched in the form of a three-dimensional nanostructure. The sulfided metal layer may be plated.

Here, the intervals in which the nanostructure groups constituting the first and second electrode portions 230 and 230 ′ are spaced apart from each other so that the plurality of nanomaterials constituting each of the nanostructure groups are wider than the spaced intervals. Groups can be in island form.

In addition, the group of nanostructures constituting the first and second electrode portions 230 and 230 ′ may be formed to be alternately arranged.

In this case, a sufficient gap between the nanostructure groups 230 and 230 'constituting the first and second electrode portions 230 and 230' may allow the electrolyte 240 to sufficiently penetrate between the nanostructure groups. can do.

According to FIG. 9D, the group of nanostructures constituting the first and second electrode portions 230 and 230 ′ may be formed to face each other at positions corresponding to each other. Even in this case, sufficient spacing between the nanostructure groups constituting the first and second electrode portions 230 and 230 ′ may allow the electrolyte 240 to sufficiently penetrate between the nanostructure groups.

According to the exemplary embodiment illustrated in FIGS. 9C and 9D, the surface area of the electrolyte 240 is sufficiently infiltrated and contacted between the group of nanostructures constituting the first and second electrode portions 230 and 230 ′. The efficiency can be improved.

Meanwhile, the configuration of the energy conversion device 400 illustrated in FIGS. 9C and 9D may be a structure in which the electrodes illustrated in FIG. 8B are disposed such that the nanostructures face each other.

10 is a flowchart illustrating a method for forming a three-dimensional nanostructure according to an embodiment of the present invention.

Referring to FIG. 10, first, the upper region of the current collector 110 is etched into a 3D nanostructure (S10). The plurality of nanostructures forming the three-dimensional nanostructure may be in the form of nanotubes, nanowires, nanorods, nanofibers, In some cases, at least one of a nano-ring and a nano-horn may be formed.

In addition, the plurality of nanostructures may have a cross section such as a circle, a rectangle, a triangle, a rhombus, or the like. Or it may be formed to have another polygonal shape, the cross-sectional shape of each nanostructure is not limited thereto.

In addition, the nanostructures 130 may be etched to be formed in a vertical direction, but this is only an example, and the direction in which the nanostructures 130 are formed is not limited.

Subsequently, the plating metal layer 120 is formed on the current collector 110 etched into the 3D nanostructure (S20).

Meanwhile, the washing and drying step may be optionally added before the step S20.

Subsequently, the current collector 110 etched in the form of a three-dimensional nanostructure in which the metal layer 120 is formed is washed with distilled water, and residual water is removed through a drying process (S30).

When the metal layer 120 of the three-dimensional structure is completed, a sulfiding solution for sulfidation is prepared (S40). Here, the sulfidation solution may be a solution in which the solution in which ammonium polysulfide and sodium sulfide are added to distilled water reaches a predetermined sulfation temperature, for example, 80 degrees. At this time, sodium sulfide, which is one of the raw materials of the sulfided solution, must be completely dissolved.

When manufacturing of the sulfided solution is completed, the sulfided solution prepared in step S30 is applied to the current collector 110 of the three-dimensional nanostructure on which the metal layer 120 is formed, and at a room temperature for a predetermined time, for example, 3 hours or more. After drying for a predetermined time, the temperature is left for a predetermined time to be sulfided (S50).

After the sulfidation process, the metal layer 120 formed on the current collector 110 having a three-dimensional nanostructure may be the metal sulfide layer 130. This is washed with distilled water, and removes residual moisture through the drying process (S60).

11 is a flowchart illustrating a method for forming a three-dimensional nanostructure according to another embodiment of the present invention.

Referring to FIG. 11, first, the upper region of the current collector 110 is etched into a 3D nanostructure (S11). The plurality of nanostructures forming the three-dimensional nanostructure may be in the form of nanotubes, nanowires, nanorods, nanofibers, In some cases, at least one of a nano-ring and a nano-horn may be formed.

In addition, the plurality of nanostructures may have a cross section such as a circle, a rectangle, a triangle, a rhombus, or the like. Or it may be formed to have another polygonal shape, the cross-sectional shape of each nanostructure is not limited thereto.

Subsequently, a plating metal layer is formed on the current collector having a three-dimensional nanostructure (S21).

Meanwhile, washing and drying steps may be optionally added before step S21.

Subsequently, the current collector 110 etched in the form of a three-dimensional nanostructure in which the plated metal layer 120 is formed is washed with distilled water, and residual water is removed through a drying process (S31).

Subsequently, a precursor solution for forming an oxide coating layer on the plating metal layer 120 is prepared (S41). The oxide coating layer may be formed of an anode oxide, a cathode oxide, a metal sulfide, or the like.

On the other hand, the precursor solution can be prepared by dissolving a metal oxide or a metal hydroxide precursor in a solvent. For example, the metal oxide or metal hydroxide precursor may include salts of metals such as Ni, Cu, Cr, Co, Zn, or Fe. Specifically, nickel nitrate, nickel acetate, nickel chloride, nickel carbonate, nickel sulfate Ferrous sulfate, cobalt sulfate, cobalt nitrate, cobalt chloride, zinc chloride, zinc sulfate, copper sulfate, cuprous chloride or potassium dichromate. However, the precursors exemplified above are just examples, and in the present invention, metal salts capable of generating hydroxides or oxides according to the pH change in the precursor solution may be used without limitation.

The kind of solvent in which a metal oxide or a metal hydroxide precursor is melt | dissolved is also not specifically limited. For example, an organic solvent excellent in mixing property with water can be used. By using such a solvent, it is possible to prepare a solvent in which water and an organic solvent are uniformly mixed, and by dissolving the metal oxide or metal hydroxide completely in the mixed solvent, it is possible to prepare a uniform solution as a whole. For example, an alcohol solvent such as methanol, ethanol, propanol or butanol may be used as the organic solvent.

When preparing a solution by injecting a metal oxide or metal hydroxide precursor into the solvent, the concentration of the solution is appropriately set according to the thickness of the desired metal oxide or metal hydroxide film, and is not particularly limited.

Subsequently, the precursor solution generated in step S41 is heat-treated on the plating metal layer 120 to form an oxide layer (not shown) (S51).

Finally, a coating layer may be optionally formed on the oxide layer (not shown) to improve conductivity. The coating layer may be formed by coating and heat-treating a polymer, oil, sugars, liquid silicone, or the like.

Meanwhile, the 3D nanostructure according to the present invention may be used as an electrode of a battery. Specifically, it may be used as an electrode of a secondary battery, a polymer battery, an electrochemical capacitor (eg, an electric double layer capacitor, a pseudo capacitor, etc.).

In addition, the three-dimensional nanostructure according to the present invention can provide a smooth electron migration path including the electrode active material by the sulfidation treatment, by including a porous three-dimensional nanostructure, it is possible to increase the electrolyte impregnation and reaction system area. As described above, other structures and structures of the battery and capacitor of the present invention containing the three-dimensional nanostructure of the present invention as an electrode active material are not particularly limited, and materials and structures common in this field may be applied without limitation.

While the above has been shown and described with respect to preferred embodiments of the invention, the invention is not limited to the specific embodiments described above, it is usually in the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Various modifications may be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

1A to 1C are cross-sectional views illustrating a process of forming a current collector-electrode integrated device according to an embodiment of the present invention.

2A to 2C are views showing the surface shape of FIGS. 1A to 1C.

3 is a graph showing charge / discharge according to a constant current test of a current collector-electrode integrated device according to an embodiment of the present invention.

4 is a graph showing the discharge capacity according to the number of cycles of the current collector-electrode integrated device according to an embodiment of the present invention.

5 is a flowchart illustrating a method of manufacturing a current collector-electrode integrated device according to an embodiment of the present invention.

6A through 6C are cross-sectional views illustrating a process of manufacturing a 3D nanostructure according to another embodiment of the present invention.

7A and 7B are cross-sectional views of three-dimensional nanostructures according to various embodiments of the present disclosure.

8A to 8D are plan views illustrating a structure of a 3D nanostructure according to various embodiments of the present disclosure.

9A to 9D are cross-sectional views illustrating a configuration of an energy conversion device according to various embodiments of the present disclosure.

10 is a flowchart illustrating a method for forming a three-dimensional nanostructure according to an embodiment of the present invention.

11 is a flowchart illustrating a method for forming a three-dimensional nanostructure according to another embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

10 current collector 20 plating metal layer

30: metal sulfide layer 110: current collector

120: metal layer 130: metal sulfide layer

Claims (11)

Etching the upper region of the current collector into a three-dimensional nanostructure; Forming a metal layer on the etched current collector; And Forming a metal compound layer on a current collector on which the metal layer is formed; The metal compound layer, Method for producing a three-dimensional nanostructure, characterized in that the metal sulfide layer formed by sulfiding the current collector on which the metal layer is formed. The method of claim 1, Forming the metal layer, A method for producing a three-dimensional nanostructure, characterized in that to form a metal layer on the current collector etched using at least one of electroless plating, electrolytic plating, sputtering and vacuum deposition. delete delete The method of claim 1, Forming a coating layer for improving the conductivity on the metal sulfide layer; Method for producing a three-dimensional nanostructure further comprising. The method of claim 1, The upper region of the current collector etched in the 3D nano form, It is formed of a plurality of nanostructures, each nanostructure is a method of manufacturing a three-dimensional nanostructures, characterized in that the shape controllable. A current collector whose upper region is etched into a three-dimensional nanostructure; A metal layer formed on the etched current collector; And And a metal compound layer formed on the current collector on which the metal layer is formed. The metal compound layer, 3D nanostructure, characterized in that the metal sulfide layer formed by sulfiding the current collector formed with the metal layer. delete The method of claim 7, wherein The coating layer for improving the conductivity formed on the metal sulfide layer; 3D nanostructure further comprising. The method of claim 7, wherein The upper region of the current collector etched in the 3D nano form, It is formed of a plurality of nanostructures, each nanostructure is a three-dimensional nanostructure, characterized in that the shape control is possible. delete

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