KR101573780B1 - Electorde material containing multi-element metal oxide deposited electrode for supercapacitor and preparation method thereof - Google Patents

Abstract

The present invention relates to an electrode for a capacitor in which an electrode material containing a multi-component metal oxide is electrodeposited and a method for manufacturing the same. According to various embodiments of the present invention, by using a multi-component metal oxide as an electrode material, it is possible to develop an electrode that can replace a conventionally expensive single-component metal oxide supercapacitor. By using a conventional conductive agent and a binder Since the electrode can be used as it is without departing from the method of manufacturing the electrode, it is possible to achieve the effect of improving the step of the process and reducing the process cost, and also, by using the manufacturing method of the present invention, nickel, cobalt and manganese It is possible to electrodeposit other metal oxides which are candidates of supercapacitors in addition to the ternary mixed metal oxide, and thus can be usefully used in the development of electrodes for lithium ion secondary batteries.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electrode for a supercapacitor to which an electrode material containing a multi-component metal oxide is electrodeposited,

The present invention relates to an electrode for a capacitor in which an electrode material containing a multi-component metal oxide is electrodeposited and a method for manufacturing the same.

Recently, demand for environmentally friendly hybrid vehicles has been gradually increasing to overcome problems such as depletion of petroleum resources. As a power source for an electric vehicle requiring high output, research on ultra-high capacity capacitors is being actively carried out. Supercapacitors, which have higher energy density than conventional capacitors and higher output densities than secondary batteries, are attracting attention as new energy storage devices.

The super capacitor includes an electric double layer capacitor (EDLC) using activated carbon as an electrode material, a conductive polymer such as polyaniline and polypyrrole, a transition metal oxide such as RuO ₂ and MnO ₂ , and a complex thereof (Mn-Ni, Mn And a pseudo-capacitor using an electrode material as an electrode material.

The currently used electric double layer capacitors (EDLC) have a porous structure of activated carbon-based material, and the activated carbon has a large specific surface area and uniform pores to provide capacitance, electric conductivity And has a high ion diffusion rate, and exhibits a low equivalent series resistance (ESR), which is stable in a wide potential range.

However, due to the limitation of the storage capacity, the low energy density acts as a limiting factor. As an alternative to the EDLC, a pseudo capacitor using metal oxide having a storage capacity three to four times larger than the EDLC is actively studied.

NiO _x , CoO _x , and MnO ₂ as the metal oxide electrode material of the pseudo capacitor have a relatively large improvement range due to poor non-storage capacity characteristics, and accordingly, a study on the manufacture and development of high capacity and low cost metal oxide electrodes . Among these, manganese, which has high price competitiveness, environmental friendliness, and abundant storage capacity, is in the form of manganese oxide and is attracting attention as a next generation secondary battery or a capacitor electrode material.

However, single manganese oxides have many points to be improved in terms of electrochemical performance, stability, and durability. Thus, various methods such as addition of a polymer or production of a binary metal oxide have been introduced to overcome the limitations.

Methods for producing metal oxides as electrode materials for pseudo-capacitors include chemical coprecipitation and freeze-drying, hydrothermal method using a high-temperature and high-pressure reactor, There is a method of producing a metal oxide or a method using a carbon nanotube nanocomposite material in which a solution for use is spun under an electric field to coat an ultrafine conductive polymer in which a metal oxide precursor, a conductive metal oxide precursor and a polymer are combined,

In the case of the sol-gel method in which the electrode material is directly deposited on the electrode, the process time is longer than several hours, and most of the methods are applied to the electrode in the powder state After the material is manufactured, the powder is always mixed with a binder for attachment to the carbon-based conductive agent and is attached to an aluminum foil to produce an electrode for a supercapacitor. Thus, the process time is lengthened and the cost Which is inefficient.

In addition, there is an electrochemical deposition method of a single-component metal oxide that has been studied in the past, but the electrodes used at this time are expensive to use expensive materials such as nickel foil and carbon nanotubes including platinum.

SUMMARY OF THE INVENTION The present invention provides an electrode material comprising a multi-component metal oxide.

Another object of the present invention is to provide an electrode for a capacitor in which an electrode material containing the multi-component metal oxide is electrodeposited.

Another problem to be solved by the present invention is to reduce the process steps of manufacturing the electrode using the powder particles used as the electrode active material, thereby reducing the processing cost. The electrodeposition method using the constant current method And a method of manufacturing the capacitor electrode.

According to an exemplary aspect of the present invention, there is provided an electrode material comprising a multi-component metal oxide having a composition represented by the following Formula 1:

[Chemical Formula 1]

M _a M ' _b M'' _c

(Wherein M, M ', M ", a, b and c are as defined herein).

According to another exemplary aspect of the present invention, there is provided an electrode for a capacitor in which an electrode material containing the multi-component metal oxide is deposited on a carbon-based substrate.

According to another exemplary embodiment of the present invention, a carbon-based substrate is immersed as a reference electrode, a counter electrode and a working electrode in a multi-component metal oxide precursor solution, and a multi-component metal oxide is electrodeposited on the substrate by applying an electric current The method of manufacturing an electrode for a capacitor according to claim 1,

According to various embodiments of the present invention, by using a multi-component metal oxide as an electrode material, it is possible to develop an electrode that can replace a conventionally expensive single-component metal oxide supercapacitor. By using a conventional conductive agent and a binder Since the electrode can be used as it is without departing from the method of manufacturing the electrode, it is possible to achieve the effect of improving the step of the process and reducing the process cost, and also, by using the manufacturing method of the present invention, nickel, cobalt and manganese It is possible to electrodeposit other metal oxides which are candidates of supercapacitors in addition to the ternary mixed metal oxide, and thus can be usefully used in the development of electrodes for lithium ion secondary batteries.

FIG. 1 is a graph showing a cyclic voltammogram of a graphite sheet electrode electrodeposited with nickel-cobalt-manganese oxide according to a scanning speed according to an embodiment of the present invention.
FIG. 2 is a graph showing a non-storage capacity of a graphite sheet electrode to which nickel-cobalt-manganese oxide is electrodeposited according to an embodiment of the present invention.
3 is a graph showing charge / discharge characteristics of a graphite sheet electrode electrodeposited with nickel-cobalt-manganese oxide according to an embodiment of the present invention.
FIG. 4 is a SEM image showing a low magnification obtained by observing the surface phenomenon of a graphite sheet electrodeposited with nickel-cobalt-manganese oxide according to an embodiment of the present invention.
FIG. 5 is a SEM image showing a high magnification image of a surface of a graphite sheet deposited with nickel-cobalt-manganese oxide according to an embodiment of the present invention.
6 is an EDAX image showing the composition of nickel-cobalt-manganese oxide on a graphite sheet electrodeposited with nickel-cobalt-manganese oxide according to an embodiment of the present invention.

Hereinafter, various aspects and various embodiments of the present invention will be described in more detail.

According to an aspect of the present invention, there is disclosed an electrode material comprising a multi-component metal oxide having a composition of the following formula:

[Chemical Formula 1]

M _a M ' _b M'' _c

Wherein M, M 'and M "are at least one metal selected from the group consisting of Ni, Co, Mn, Fe, Ir, V and Ti, Wherein a, b and c are atomic percentages of the metal, a, b and c are real numbers, and a + b + c = 100.

Preferably, the electrode material comprising the multi-component metal oxide has a composition of the following formula 1:

[Chemical Formula 1]

M _a M ' _b M'' _c

B, and c are atomic percentages of the metal, and a, b, and c are the atomic percentages of the metal, and M " Wherein a is 10? A? 80, b is 5? B? 35, c is 5? C? 80, and a + b + c = 100.

More preferably, the electrode material comprising the multi-component metal oxide has a composition represented by the following Formula 1:

[Chemical Formula 1]

M _a M ' _b M'' _c

B, and c are atomic percentages of the metal, and a, b, and c are the atomic percentages of the metal, and M " Wherein a is 50? A? 75, b is 5? B? 35, c is 5? C? 25, and a + b + c = 100.

Most preferably, the multicomponent metal oxide is selected from the group consisting of Ni ₆₁ Co ₂₆ Mn ₁₃ , Ni ₇₀ Co ₁₀ Mn _{20 ,} Ni ₆₁ Co ₂₆ Fe ₁₃ And the like.

According to an embodiment of the present invention, among the electrode materials containing a multi-component metal oxide, the nickel content is the highest at 50 to 75, so that the effect of thermal stability can be achieved. Particularly, Ni ₆₁ Co ₂₆ Mn ₁₃ The electrode material having the composition has a nickel content of about 5 times or more higher than the manganese content, so that it is possible to inhibit corrosion in the electrolytic solution in the aqueous solution and achieve the effect of electrochemical stability.

According to another aspect of the present invention, there is provided an electrode for a capacitor in which an electrode material containing the multi-component metal oxide is electrodeposited on a carbon-based substrate.

According to one embodiment of the present invention, the electrode for a capacitor exhibits a high operating life over a water-soluble electrolyte at a wide operating voltage of 1.5 V or more and an initial non-storage capacity of 10,000 cycles or more, and thus can be very useful as a capacitor electrode have.

In one embodiment of the present invention, the electrode material containing the multi-component metal oxide is electrodeposited in the form of spherical particles on a carbon-based substrate.

According to an embodiment of the present invention, the electrode material including the multi-component metal oxide may be electrodeposited in the form of spherical particles stacked on a carbon-based substrate.

In another embodiment of the present invention, the carbon-based substrate is characterized by being at least one selected from a graphite sheet and a nickel foil.

In another embodiment of the present invention, the electrode has a reserve capacity of 200600 F / g at a current density of 2060 A / g.

According to an embodiment of the present invention, when the scanning speed is 20 mV / s, the capacitance of the capacitor is very high at 550.1 F / g, and at a scanning speed of 300 mV / s, 224.2 F / g , Indicating a high non-storage capacity. In addition, it was confirmed that the non-storage capacity of 423 F / g is high even when the current density is as high as 50 A / g, which means that the non-storage capacity of 100-200 F / g at the current density of 30 A / (See Experimental Example 1 and Figs. 1 to 3).

According to another aspect of the present invention, there is provided a method of manufacturing a multi-component metal oxide precursor solution, comprising: immersing a carbon-based substrate as a reference electrode, a counter electrode, and a working electrode in a multi-component metal oxide precursor solution; A method of manufacturing an electrode for a capacitor is disclosed.

In one embodiment of the present invention, the electrodeposition current to be applied is in the range of -50 mA / cm ² to -100 mA / cm ² .

According to an embodiment of the present invention, in the process of applying current, which is an essential condition for electrodeposition of a multi-component metal oxide on a carbon-based substrate, the content of electrodeposited multi-component metal oxide increases as the current increases. When the applied current is less than mA / cm ^{2, the} electrodeposition may occur due to the lack of reduction due to insufficient current density. If the current is applied at a current higher than -100 mA / cm ² , The generation reaction occurs largely, which interferes with electrodeposition.

In another embodiment of the present invention, the multicomponent metal oxide precursor solution is prepared by adding a third precursor solution to a mixed precursor solution obtained by mixing a first precursor solution and a second precursor solution,

Wherein the molar ratio of the second precursor to the first precursor in the mixed precursor solution is from 2: 1 to 3: 1,

The molar ratio of the first precursor to the third precursor in the multicomponent metal oxide precursor solution is 10: 1 to 30: 1,

Wherein the first precursor, the second precursor and the third precursor are selected from the group consisting of nickel chloride (NiCl ₂揃 6H ₂ O), cobalt chloride (CoCl ₂揃 6H ₂ O), manganese acetate (Mn (CH ₃ COO) ₂揃 4H ₂ O) .

In another embodiment of the present invention, the multi-component metal oxide is characterized by having a composition represented by the following formula (1)

[Chemical Formula 1]

M _a M ' _b M'' _c

Wherein M, M 'and M "are at least one metal selected from the group consisting of Ni, Co, Mn, Fe, Ir, V and Ti, Wherein a, b and c are atomic percentages of the metal, a, b and c are real numbers, and a + b + c = 100.

Preferably, the multicomponent metal oxide has a composition of the following formula:

[Chemical Formula 1]

M _a M ' _b M'' _c

B, and c are atomic percentages of the metal, and a, b, and c are the atomic percentages of the metal, and M " Wherein a is 10? A? 80, b is 5? B? 35, c is 5? C? 80, and a + b + c = 100.

More preferably, the multi-component metal oxide is characterized by having a composition represented by the following formula:

[Chemical Formula 1]

M _a M ' _b M'' _c

B, and c are atomic percentages of the metal, and a, b, and c are the atomic percentages of the metal, and M " B is a real number, 50? A? 75, b is 5? B? 35, c is 5? C? 25, and a + b + c = 100.

Most preferably, the multicomponent metal oxide is selected from the group consisting of Ni ₆₁ Co ₂₆ Mn ₁₃ , Ni ₇₀ Co ₁₀ Mn _{20 ,} Ni ₆₁ Co ₂₆ Fe ₁₃ And the like.

In another embodiment of the present invention, the reference electrode is at least one electrode selected from Ag / AgCl, a reference hydrogen electrode (SHE), a standard hydrogen electrode (NHE), and a calomel.

In another embodiment of the present invention, the carbon-based substrate used as the working electrode is at least one selected from a graphite sheet and a nickel foil.

In another embodiment of the present invention, the carbon-based substrate comprises: (a) performing a polishing operation on the surface of the carbon-based substrate to increase the roughness;

(b) dipping the carbon-based substrate obtained in step (a) in an aqueous acid solution of at least one selected from 10-30 wt% sulfuric acid, 20-30 wt% nitric acid or hydrochloric acid to etch the surface;

(c) a step of immersing the carbon-based substrate obtained in the step (b) in a C ₁ -C ₆ alcohol to remove micro-defects and impurities.

In still another embodiment of the present invention, the substrate on which the multi-component metal oxide oxide is deposited may further include a heat treatment at a temperature of 100-300 ° C.

As a concrete example according to one embodiment of the present invention, if a method for manufacturing an electrode for a capacitor in which a multicomponent metal oxide has a composition of Ni ₆₁ Co ₂₆ Mn ₁₃ and a carbon-based substrate is graphite,

Cobalt-manganese oxide on the substrate by immersing Ag / AgCl and a counter electrode as a reference electrode in a nickel-cobalt-manganese precursor solution and a graphite substrate as a working electrode and applying a current of -50 mA to -75 mA, The method may further include a step of heat-treating the substrate to which the multi-component metal oxide oxide is deposited at a temperature of 100-300 ° C.

The metal oxide precursor solution having the composition of Ni ₆₁ Co ₂₆ Mn ₁₃ is a bath prepared for electrodepositing a metal oxide oxide having a composition of nickel-cobalt-manganese on a carbon-based substrate, Preferably:

(I) mixing a nickel precursor solution and a cobalt precursor solution to obtain a nickel-cobalt precursor mixture solution; And

(Ii) adding a manganese precursor solution to the nickel-cobalt precursor mixed solution obtained in the step (i).

According to an embodiment of the present invention, in order to prepare the nickel-cobalt-manganese oxide precursor solution, the order of the mixing of the precursor solutions is important. When the mixing process of the solution is not sequentially performed, There may be a problem of stable compound formation or precipitation generation of the molecular state in the solution due to chemical interaction of the compound.

The nickel-cobalt precursor mixture solution and the manganese precursor solution were mixed in a volume ratio of 1: 1,

The molar concentration of the nickel precursor solution is 0.08-0.2 M, the molar concentration of the cobalt precursor solution is 0.02-0.05 M, and the molar concentration of the manganese precursor solution is 0.001-0.0025 M.

On the other hand, the graphite substrate includes: (a) performing a polishing operation on the graphite surface to increase the roughness;

(b) etching the surface of the graphite substrate obtained in step (a) by immersing the graphite substrate in at least one acid aqueous solution selected from 10-30 wt% sulfuric acid, 20-30 wt% nitric acid or hydrochloric acid;

(c) a step of immersing the graphite substrate obtained in the step (b) in a C ₁ -C ₆ alcohol to remove micro-defects and impurities.

According to another aspect of the present invention, there is provided a plasma display panel comprising: (A) an electrode for a capacitor in which an electrode material containing the multi-component metal oxide is electrodeposited on a carbon-based substrate; (B) an electrolyte; (C) a current collector; And (D) a separator, wherein the electrolyte (B) is at least one water-soluble electrolyte selected from Na ₂ SO ₄ , KOH, KCl, and H ₂ SO ₄ .

According to an embodiment of the present invention, when the water-soluble electrolyte is used as the electrolyte of the conventional capacitor, there is a problem that the performance of the battery is deteriorated. However, the capacitor of the present invention can be used even if the electrolyte of 0.5 M Na ₂ SO ₄ is used as the electrolyte, And the charge / discharge results of the battery can be obtained.

In one embodiment of the present invention, the capacitor is a supercapacitor.

Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the scope and content of the present invention can not be construed to be limited or limited by the following Examples. In addition, it is apparent that, based on the teachings of the present invention including the following examples, those skilled in the art can easily carry out the present invention in which experimental results are not specifically shown.

Example  One

(1) Step 1: Pretreatment of graphite sheet for working electrode

The following experiment was carried out to pretreat the graphite sheet used for the working electrode.

First, a physical polishing operation to rub the graphite sheet with silicon carbide paper (SiC paper) to increase the roughness of the surface was performed. Then, the surface was chemically etched by soaking in 20 wt% sulfuric acid for 20 seconds, The graphite sheet thus formed was immersed in a 2M ethanol solution for 20 seconds to remove micro-level defects and impurities.

The pretreated graphite sheet was taken out of ethanol, washed with distilled water, and then dried in an oven at 65 ° C for 6 hours to remove moisture completely.

Before electrodeposition, a sheet that had been thoroughly dried was prepared and kept in such a way as to avoid exposure to the air as much as possible.

(2) Step 2: Preparation of precursor solution

NiCl ₂ · 6H ₂ O), cobalt chloride (CoCl ₂ · 6H ₂ O), and manganese acetate (Mn (CH ₃ COO) ₂ · 4H ₂ O) reagents were prepared for the preparation of ternary metal oxide electrodes for supercapacitors Nickel, cobalt, and manganese oxides.

First, nickel and cobalt precursor solutions were prepared at 0.1 M and 0.04 M concentrations, respectively, so that the molar ratio of cobalt to nickel in solution was 2.5: 1, and then mixed to prepare a nickel-cobalt mixed solution. The manganese precursor solution was separately prepared at a concentration of 0.005 M so that the molar ratio of manganese to nickel was 20: 1.

(3) Step 3: Preparation of ternary mixed solution for electrodeposition

The mixed solution of nickel-cobalt precursor and the manganese precursor solution prepared in the step 2 were mixed at a volume ratio of 1: 1 and stirred for 1 to 2 minutes to prepare the mixed nickel-cobalt-manganese solution.

(4) Step 4: Electrodeposition and Oxide Crystallization

The graphite sheet (exposed area: 2.5 cm x 3 cm) prepared in the above step 1 was connected to the working electrode and the counter electrode, and the solution of the nickel-cobalt-manganese precursor obtained in the above step 3 was used with the Ag / AgCl electrode as the reference electrode Which was installed in a bath. Electrodeposition proceeded at room temperature and proceeded by the method of galvanostatic method. The applied current was -75 mA and the electrodeposition was carried out for 2 minutes.

The surface of the electrodeposited graphite sheet was washed with distilled water, and water was removed to measure the electrodeposited mass. In the case of the graphite sheet, the graphite sheet was dried in an oven at 65 ° C for 6 hours to remove water. After mass measurement, annealing was carried out at 250 ° C for 3 hours for oxide crystallization.

Experimental Example  1: electrochemical analysis

Electrochemical analysis was performed by 3-electrode method. The potentiostat used in the experiment was Prinston VSP equipment.

Ag / AgCl was used as a reference electrode, and a graphite sheet on which the nickel-cobalt-manganese oxide was electrodeposited was connected to a working electrode, and a platinum mesh-coated Ti electrode coated with titanium on titanium After the connection, electrochemical analysis was performed after installing in a bath containing 0.5 M Na ₂ SO ₄ electrolyte.

As shown in the cyclic voltammetry graph showing the performance of the graphite sheet electrode electrodeposited with nickel-cobalt-manganese oxide as a supercapacitor, as shown in FIG. 1, although the scanning speed is increased, Respectively.

As shown in FIG. 2, the non-storage capacity of the graphite sheet electrode electrodeposited with nickel-cobalt-manganese oxide was measured according to the scanning speed. As a result, the non-storage capacity at 20 mV / s was 550.1 F / , And it was confirmed that even at a high scanning speed of 300 mV / s, a high non-storage capacity of 224.2 F / g was obtained.

Further, as shown in FIG. 3, the charge reversal characteristics of the nickel-cobalt-manganese oxide electrodeposited graphite sheet were examined. As a result, it was found that the discharge time of 16.08 seconds at a high current density of 50 A / g, Capacity, which exhibits higher performance than metal oxide capacitors having a current limit of about 100-200 F / g at a current density of 30 A / g.

Experimental Example  2: Characteristic evaluation

The surface phenomenon of the graphite sheet electrodeposited with the nickel-cobalt-manganese oxide was observed with a scanning microscope (Jeol Co., JEM 5200). The results are shown in FIGS. 4 and 5, The composition of the electrodeposited layer was analyzed by an energy dispersive X-ray spectrometer (EDAX; Oxford instrument D6841), and the results are shown in Table 1 and FIG.

As shown in FIGS. 4 and 5, the nickel-cobalt-manganese oxide electrodeposited on the graphite sheet was found to be electrodeposited in the form of spherical particles, which is a thin film when electrodepositing a single- , And it was confirmed that the nickel-cobalt-manganese oxide particles were electrodeposited on the entire graphite sheet in the stacked form as shown in the low magnification of FIG. 4.

Element C O Mn Co Ni Atomic% 9.43 34.39 6.94 14.89 34.36

As shown in Table 1, the EDAX image analysis confirmed that the nickel-cobalt-manganese oxide was composed at a ratio of about Ni ₆₁ Co ₂₆ Mn ₁₃ , and the presence of chlorine (Cl) in the EDAX image of FIG. The amount detected by the cobalt precursor is less than about 1% of the total amount, so it is excluded from the entire constituents.

Claims (16)

delete An electrode material comprising a multicomponent metal oxide having a composition represented by the following formula:
[Chemical Formula 1]
M _a M ' _b M'' _c
(In the formula 1,
Wherein M is Ni,
M 'is Co,
M " is Mn or Fe,
Wherein a, b and c are atomic percentages of the metal,
Wherein a, b and c are real numbers,
a is 50? a? 75,
B is 5 ≤ b ≤ 35,
Wherein c is 5? C? 25,
a + b + c = 100).
An electrode for a capacitor, wherein the electrode material comprising the multi-component metal oxide of claim 2 is deposited on a carbon-based substrate.
The method of claim 3,
Wherein the carbon-based substrate is graphite or nickel foil.
The method of claim 3,
Wherein the electrode has a specific capacity of 200-600 F / g at a current of 20-60 A / g.
A method for manufacturing an electrode for a capacitor, comprising: immersing a carbon-based substrate as a reference electrode, a counter electrode, and a working electrode in a solution of a multi-component metal oxide precursor; and applying an electric current to deposit a multi-component metal oxide on the substrate ,
Wherein the multi-component metal oxide has a composition represented by the following formula (1): < EMI ID =
[Chemical Formula 1]
M _a M ' _b M'' _c
(In the formula 1,
Wherein M is Ni,
M 'is Co,
M " is Mn or Fe,
Wherein a, b and c are atomic percentages of the metal,
Wherein a, b and c are real numbers,
a is 50? a? 75,
B is 5 ≤ b ≤ 35,
Wherein c is 5? C? 25,
a + b + c = 100).
The method according to claim 6,
Wherein the current is from -50 mA / cm ² to -100 mA / cm ² .
The method according to claim 6,
The multi-component metal oxide precursor solution is prepared by adding a third precursor solution to a mixed precursor solution obtained by mixing a first precursor solution and a second precursor solution,
Wherein the molar ratio of the first precursor to the second precursor in the mixed precursor solution is from 2: 1 to 3: 1,
The molar ratio of the first precursor to the third precursor in the multicomponent metal oxide precursor solution is 10: 1 to 30: 1,
Wherein the first precursor, the second precursor and the third precursor are selected from the group consisting of nickel chloride (NiCl ₂揃 6H ₂ O), cobalt chloride (CoCl ₂揃 6H ₂ O), manganese acetate (Mn (CH ₃ COO) ₂揃 4H ₂ O ). ≪ / RTI >
delete delete The method according to claim 6,
Wherein the reference electrode is one electrode selected from Ag / AgCl, a reference hydrogen electrode, a standard hydrogen electrode, and a calomel.
The method according to claim 6,
Wherein the carbon-based substrate is a graphite sheet or a nickel foil.
The method according to claim 6,
The carbon-based substrate may include (a) performing a polishing operation on the surface of the carbon-based substrate to increase the roughness;
(b) dipping the carbon-based substrate obtained in step (a) in an aqueous acid solution of at least one selected from 10-30 wt% sulfuric acid, 20-30 wt% nitric acid or hydrochloric acid to etch the surface;
(c) immersing the carbon-based substrate obtained in the step (b) in a C ₁ -C ₆ alcohol to remove micro-defects and impurities, thereby obtaining a capacitor electrode.
The method according to claim 6,
Wherein the substrate on which the multi-component metal oxide oxide is deposited is further subjected to a heat treatment at a temperature of 100-300 ° C.
(A) an electrode for a capacitor in which an electrode material comprising the multi-component metal oxide of claim 2 is deposited on a carbon-based substrate;
(B) an electrolyte;
(C) a current collector; And
(D) a separating film,
Wherein the electrolyte (B) is at least one aqueous solution selected from Na ₂ SO ₄ , KOH, KCl, and H ₂ SO ₄ .
16. The method of claim 15,
Wherein the capacitor is a supercapacitor.

Images