KR101736096B1

KR101736096B1 - Preparation method of mesoporous NiCo2O4 nanostructures

Info

Publication number: KR101736096B1
Application number: KR1020160008204A
Authority: KR
Inventors: 심재진; 웬방호아; 라미엘샤메인산흐세
Original assignee: 영남대학교 산학협력단
Priority date: 2016-01-22
Filing date: 2016-01-22
Publication date: 2017-05-16

Abstract

The present invention relates to a preparation method of a mesoporous NiCo_2O_4 nanostructure. In the case where the mesoporous NiCo_2O_4 nanostructure produced by the preparation method is used as an active material of an electrode, the nanostructure shows a high specific capacitance of 879 and 343 F/g in the current density of 0.5 and 20 A/g, respectively; reduction in the capacitance after using the nanostructure for 1,500 times is only 4.7% compared to the initial capacity, and thus the nanostructure shows excellent circulation stability; and a composite can be simply and effectively produced.

Description

Preparation method of mesoporous NiCo2O4 nanostructures < RTI ID = 0.0 >

The present invention relates to a method for producing a NiCo ₂ O ₄ nanostructure having a mesoporous structure.

The super capacitor is an energy storage device that stores and supplies electric energy by using the capacitor behavior caused by the electrochemical reaction between the electrode and the electrolyte. The super capacitor is superior in energy density and power density to the conventional electrolytic capacitor and the secondary battery, It is a new concept of energy storage power source that can store and supply energy quickly.

Generally, supercapacitor electrode materials can be classified into three types including carbonaceous materials, conducting polymers, and transition metal oxides / hydroxides. Among them, considerable attention has been devoted to transition metal oxides / hydroxides with various valence states known as pseudocapacitive materials due to their advantages with excellent theoretical specific capacitance and high energy density , RuO ₂ has typically exhibited significant non-storage capacities and electrochemical reversibility, but RuO ₂ is expensive and rarely limits commercial and practical applications, so that much effort has been devoted to replacing replaceable metals for supercapacitor applications Have been devoted to the development of oxide electrode materials.

Recently, nickel cobaltite (NiCo ₂ O ₄ ) has attracted much attention as a potential candidate for achieving the above object. The nickel cobaltite (NiCo ₂ O ₄ ) is a low cost, abundant resource and environmental friendliness But has very high electrical conductivity (at least 100 times) and electrochemical activity better than NiO and Co ₃ O ₄ .

Various methods for preparing the mesoporous structure of NiCo ₂ O ₄ have been proposed. For example, a sol-gel method, a coprecipitation method, a hydrothermal synthesis method, a microwave irradiation method, microwave irradiation and electrodeposition have been proposed. However, most of these methods require a large amount of dangerous organic chemicals, stabilizers, and complex synthetic pathways that are harmful to the environment and require costly processes. This is pointed out as a problem.

It is therefore necessary to develop efficient and cost effective methods and to use "green" solvents.

Korea Patent No. 1563231

It is an object of the present invention to provide a method for producing a NiCo ₂ O ₄ nanostructure using a NiCo ₂ O ₄ nanostructure having a mesoporous structure obtained by irradiating a microwave on a mixture formed by dissolving a nickel precursor and a cobalt precursor in deionized water and an ionic liquid, Non-storage capacity and stability.

In order to accomplish the above object, the present invention provides a method for producing a nickel-cobalt precursor, comprising: dissolving a nickel precursor and a cobalt precursor in deionized water and an ionic liquid to form a mixture; Adding oxalic acid and sodium hydroxide to the mixture, and stirring and dissolving the mixture; Heating the mixture to which oxalic acid and sodium hydroxide have been added by irradiating microwave in a microwave reactor; Cooling the nanostructured NiCo ₂ O ₄ nanostructure to a room temperature after the microwave irradiation, centrifuging the nanostructure, and washing and drying the separated NiCo ₂ O ₄ nanostructure; And firing the dried NiCo ₂ O ₄ nanostructure of the mesoporous structure. The present invention also provides a method for producing a NiCo ₂ O ₄ nanostructure having a mesoporous structure.

The present invention also provides a NiCo ₂ O ₄ nanostructure having a mesoporous structure produced by the above production method.

When the mesoporous NiCo ₂ O ₄ nanostructure obtained by the production process according to the present invention is used as an electrode active material, it has a high non-storage capacity of 879 and 343 F / g at current densities of 0.5 and 20 A / g, respectively And the storage capacity after 1,500 times of use is only 4.7% of the initial capacity, which shows excellent cyclic stability. Thus, the NiCo ₂ O ₄ nanostructure of the mesoporous structure is very useful as various electrode materials. Can be manufactured in a simple and effective manner.

1 is a view showing a process for producing a NiCo ₂ O ₄ nanostructure having a mesoporous structure.
2 is a SEM image of NiCo ₂ O ₄ nanorods (a, b) having a mesoporous structure and NiCo ₂ O ₄ nanoparticles (c, d) having a mesoporous structure.
FIG. 3 is a TEM image of a mesoporous NiCo ₂ O ₄ nanorod (a, c), a mesoporous NiCo ₂ O ₄ nanoplate (b), and an HRTEM image of a mesoporous NiCo ₂ O ₄ nanoplate d.
FIG. 4 shows the XRD patterns of mesoporous NiCo ₂ O ₄ precursors after microwave irradiation for 10 minutes (a) and 15 minutes (b), wherein the mesoporous NiCo ₂ O ₄ nanorod XRD pattern (c) , And an XRD pattern (d) of a mesoporous NiCo ₂ O ₄ nano-plate.
Figure 5 is the XPS examination of NiCo ₂ O ₄ nano-plate of the mesopore structure (a), the mesoporous structure NiCo the ₂ O ₄ nano-board Ni 2p (b), 2p ( c) , and O 1s (d) of the Co High-resolution XPS.
6 is a view showing a nitrogen adsorption and desorption of NiCo ₂ O ₄ nano-plate of the mesopore structure isotherm (a), the mesoporous structure of NiCo ₂ O ₄ nano-pore size distribution plate (b).
Figure 7 is 1 NiCo ₂ O ₄ nano rods and nano-board-discharge curves (a), mesopores structure of NiCo ₂ O ₄ Age of the nano rods and nano plate Nyquist diagram of the mesoporous structure, with a current density in A / g ( (C) of the electrode using NiCo ₂ O ₄ nanoparticles of the mesoporous structure as the active material at various scan rates (2, 5, 10, and 20 mV / s); The galvanostatic discharge curves (d) of electrodes using mesoporous NiCo ₂ O ₄ nanoparticles as active materials at various current densities (0.5, 1, 2, 4, 8 A / g) of NiCo ₂ O ₄ used the recovery of the electrode used as the nanorods and the constant current ratio power storage capacity of the electrode using a nano panreul active material retention ratio (e), the active material of NiCo ₂ O ₄ nano-plate of the mesopore structure at a current density of 4 a / g (F) of the comparative average non-storage capacity.

Hereinafter, the present invention will be described in more detail.

The inventors of the present invention have found that when a NiCo ₂ O ₄ nanostructure having a mesoporous structure prepared by irradiating an ionic liquid and a microwave is used for an electrode as an active material, the electrode has a high non-storage capacity and an excellent circulation cycle stability. The present invention has been completed based on this finding.

The present invention relates to: Dissolving the nickel precursor and the cobalt precursor in deionized water and an ionic liquid to form a mixture; Adding oxalic acid and sodium hydroxide to the mixture, and stirring and dissolving the mixture; Heating the mixture to which oxalic acid and sodium hydroxide have been added by irradiating microwave in a microwave reactor; Cooling the nanostructured NiCo ₂ O ₄ nanostructure to a room temperature after the microwave irradiation, centrifuging the nanostructure, and washing and drying the separated NiCo ₂ O ₄ nanostructure; And firing the dried NiCo ₂ O ₄ nanostructure of the mesoporous structure. The present invention also provides a method for producing a NiCo ₂ O ₄ nanostructure having a mesoporous structure.

The nickel precursor may be at least one selected from the group consisting of nickel acetate tetrahydrate (Ni (CH ₃ COO) ₂ .4H ₂ O), nickel nitrate hexahydrate (Ni (NO ₃ ) ₂ .6H ₂ O) (NiCl ₂ .4H ₂ O), and the cobalt precursor is any one selected from the group consisting of cobalt acetate tetrahydrate (Co (CH ₃ COO) ₂ .4H ₂ O), cobalt nitrate hexahydrate (Co ₃ ) ₂ · 6H ₂ O), and cobalt chloride · tetrahydrate (CoCl ₂ · 4H ₂ O), but the present invention is not limited thereto.

The ionic liquid may also be selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluoroborate 3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, and 1-butyl-3-methylimidazolium bis (trifluoromethylsulfate) (1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide), but the present invention is not limited thereto.

In addition, the mixture in which oxalic acid and sodium hydroxide are added may be heated in a microwave reactor for 5 to 20 minutes to 80 to 120 ° C to irradiate the microwave, but the present invention is not limited thereto.

The dried mesoporous NiCo ₂ O ₄ nanostructure may be calcined at 250-350 ° C. for 1-3 hours at a ramping rate of 0.5-1.5 ° C./min, but is not limited thereto .

In addition, the NiCo ₂ O ₄ nanostructure of the mesoporous structure has a mesopore structure of NiCo ₂ O ₄ nanorod or And may be a mesoporous NiCo ₂ O ₄ nano-plate, but is not limited thereto.

The NiCo ₂ O ₄ nanorods of the mesoporous structure can be obtained by heating for 10 minutes at 100 ° C. by microwave irradiation. The mesoporous NiCo ₂ O ₄ nanoparticles were heated at 100 ° C. for 15 minutes This can be obtained by examining microwaves.

The present invention also provides a mesoporous NiCo ₂ O ₄ nanostructure produced by the above process.

In addition, the mesoporous NiCo ₂ O ₄ nanostructure may be a material of a supercapacitor electrode, a secondary battery electrode, a catalyst, or a sensor, but is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited by these examples.

&Lt; Example 1 > A mesoporous NiCo ₂ O ₄ Manufacture of nanorods

All chemicals used in the experiments were used without purification.

As a typical synthesis method of a mesoporous NiCo ₂ O ₄ nanorod, 0.1 mmol of nickel acetate · tetrahydrate (Ni (CH ₃ COO) ₂ · 4H ₂ O) and 0.1 mmol of cobalt acetate · Co (CH ₃ COO) ₂ · 4H ₂ O) was dissolved in 0.6 mL of deionized water and 0.4 mL of 1-butyl-3-methylimidazolium tetrafluoroborate (hereinafter referred to as [BMIM] [BF ₄ ] After dissolving in a mixed solvent, 0.3 mmol of oxalic acid (H ₂ C ₂ O ₄ ) and 0.1 mL of 0.5 M sodium hydroxide aqueous solution were added for 10 minutes while stirring.

After adding oxalic acid and an aqueous solution of sodium hydroxide, the mixture was heated to 100 DEG C for 10 minutes in a microwave reactor (CEM Discover) and then cooled to room temperature. The sample was separated by centrifugation and washed with deionized water and absolute ethanol ) And dried in air. Finally, the dried sample was placed in a quartz tube and calcined at 300 ° C. for 2 hours at a heating rate of 1 ° C./min to synthesize a mesoporous NiCo ₂ O ₄ nanorod.

&Lt; Example 2 > A mesoporous NiCo ₂ O ₄ Manufacture of nano plates

And the microwave irradiation time was 15 minutes.

<Experimental Example 1> A mesoporous NiCo ₂ O ₄ Characterization of nanorods and nanoplates

SEM (Hitachi, S-4200) was used as a scanning electron microscope (SEM) to analyze the characteristics of the previously prepared mesoporous NiCo ₂ O ₄ nanorods and nanoparticles, X-ray diffraction (XRD) was performed by using a Cu Kα-ray diffraction (XRD) spectrophotometer, and the transmission electron microscope (TEM) X-ray photoelectron spectroscopy (XPS) was performed using X-ray photoelectron spectroscopy (XPS) using Al Kα monochromatized radiation (Thermo Scientific , K-Alpha), respectively.

FIG. 2 shows an SEM image of a mesoporous NiCo ₂ O ₄ nanorod (a, b) and a mesoporous NiCo ₂ O ₄ nanoplate (c, d) The NiCo ₂ O ₄ nanostructure of the mesoporous structure produced by the irradiation showed two different morphologies. When the microwave and the heat treatment were performed for 10 minutes, the resultant NiCo ₂ O ₄ nanostructure product was found to be 50 It was a nanorod with diameters of -100 nm and various micrometer lengths. Microwave treatment for 15 minutes revealed that the mesoporous NiCo ₂ O ₄ nanostructure had a thin plate structure of several hundred nanometers in size.

3 is a TEM image showing the morphology of the mesoporous NiCo ₂ O ₄ nanorods and nanoparticles. The NiCo ₂ O ₄ nanorods (FIG. 3 (a) and FIG. 3 (c) ) And a nano plate (Fig. 3 (b)). The structure of the mesoporous structure is a result of improving the electrochemical performance of the electrode / electrolyte The contact area can be significantly improved, and with reference to the inset in FIG. 3 (c), the selected-area electron diffraction pattern can be used to characterize the high polycrystalline nature of the obtained product, NiCo ₂ O ₄ nanorod Lt; RTI ID = 0.0 > diffraction < / RTI >

Referring to FIG. 3 (d), FIG. 3 (d) shows a high-resolution TEM image of a mesoporous NiCo ₂ O ₄ nanoparticle having a size of about 5 to 20 nm, 0.25, 0.28, and 0.47 nm, which are close to the theoretical plate interval of the NiCo ₂ O ₄ (311), (220) and (111) planes.

4, a wide angle X-ray diffraction pattern of a NiCo ₂ O ₄ nanorod and a nano plate of a mesoporous structure before and after firing is shown. After microwave irradiation, a prepared mesoporous structure of NiCo ₂ The O ₄ precursor is a typical crystalline pattern (Figs. 4 (a) and 4 (b)) conforming to the presence of nickel oxalate (JCPDS No. 01-0296) and cobalt oxalate (JCPDS No.01-02-99) . (111), (220), (311), (222), (400), (422), (511), (440) and (440) after pyrolysis of the cobalt oxalate precursor at 300 ° C for 2 hours. 53.1) and exhibits 2? Of 19.1, 31.4, 36.8, 38.3, 44.9, 55.8, 59.3, 65.1 and 73.5 degrees with a standard peak indicated by a red line, and spinel NiCo ₂ O ₄ polycrystalline structure (JCPDF file no. 20-0781).

5, high-resolution XPS of Ni 2p (b), Co 2p (c) and O 1s (d) of a mesoporous NiCo ₂ O ₄ nanoplate is shown, The oxidation state of the pore structure NiCo ₂ O ₄ nanoparticles was obtained by XPS.

The O 1S spectra (FIG. 5 (b)) show the above survey spectra and core-level Ni 2p, Co 2p and O 1s peaks at 529.6, 530.8, 532.1 and 534.0 eV The binding energies represent four peaks, meaning O _I , O _II , O _III , and O _IV , respectively. The O _I is the metal-refers to oxygen bond, and the O _II is hydroxy, and is related to the oxygen of the hydroxyl groups, in particular O 1s present in the spectrum of O _II on the surface of the mesoporous structure of NiCo ₂ O ₄ is NiCo ₂ O ₄ Indicating that the surface of the material has been hydroxylated as a result of substitution of oxygen atoms by surface oxyhydroxide or hydroxyl groups. The O _III component is also caused by more defect sites with hypoxic coordination observed in materials with small particles, which O < RTI ID = 0.0 > _IV < / RTI > is absorbed physically and chemically at or near the surface Which corresponds to the multiplicity of the water.

Referring to FIG. 5 (c), FIG. 5 (c) shows a high resolution XPS of Co 2p, wherein the Co 2p peak has two spin-orbit doublets, Co ²⁺ and Co ³⁺ 5 (b), the Ni 2p spectrum is divided into two rotating-orbit pairs, which are characterized by Ni ²⁺ and Ni ³ , and two satellites, . These XPS results show that the surface of NiCo ₂ O ₄ has a composition including Co ²⁺ , Co ³⁺ , Ni ²⁺ , and Ni ³⁺ , and the formula of NiCo ₂ O ₄ is generally expressed as Co ²⁺ _1-x Co ³⁺ _x [Co ³⁺ Ni ²⁺ _x Ni ³⁺ _1-x ] O ₄ (0 < x < 1) (cations in brackets are in octahedral sites and outward cations are in tetrahedral sites). The atomic ratio of Co and Ni of the NiCo ₂ O ₄ was about 2: 1, which is very close to the precursor injection amount.

As 6, Figure 6 shows the pore size distribution (b) of the mesopore structure of NiCo ₂ O ₄ nano-plate of the nitrogen adsorption and desorption isotherms (a), mesopores structure of NiCo ₂ O ₄ nano-plates, this experiment was a porous properties of the mesoporous structure of NiCo ₂ O ₄ nano-structures, the NiCo ₂ O ₄ nano-rods, and a specific surface area of NiCo ₂ O ₄ nano-plates, respectively 122.3 and 75.8 m ² / g. In addition, the mesoporous NiCo ₂ O ₄ nano-plate includes an adsorption / desorption hysteresis loop, which implies the existence of a mesopore structure among the structures. The average pore sizes of the mesoporous NiCo ₂ O ₄ nanorods and NiCo ₂ O ₄ nanoparticles were 3.8 and 4.7 nm, respectively, and the nanoparticles showed slightly higher porosity than the nanorods. The mesoporous NiCo ₂ O ₄ nanostructures have a significant effect on electrochemical performance due to their ability to promote mass diffusion / transport (eg, penetration of electrolyte and ion transfer) and ensure a high electroactive surface area . Therefore, it is thought that the nanoparticles have high performance in electrochemical applications.

&Lt; Experimental Example 2 > A mesoporous NiCo ₂ O ₄ Performance analysis of electrodes using nanorods and nano-plates as active materials

The electrochemical tests were carried out using NiCo ₂ O ₄ nanorods and nanoparticles of mesoporous structure prepared in Examples 1 and ₂ as active materials. The electrochemical analysis, that is, cyclic voltammogram (CV), chronopotentiometry (CP) and electrochemical impedance spectroscopy (EIS), is a three-electrode constant voltage / constant current (potentiostat / galvanostat, Autolab PGSTAT 302N). Platinum foil and Ag / AgCl electrodes were used as counter electrodes and reference electrodes, respectively. The working electrode was prepared by mixing the prepared powder (2 mg, 80 wt%) containing the sample with 15 wt% acetylene black and 5 wt% polytetrafluoroethylene (PTFE) binder, 1.0 cm x 1.0 cm). A 6 M aqueous KOH solution was used as the electrolyte. The non-storage capacity (C _S ) of the electrode was calculated using the following equation.

The C _s, I, T, M, and ΔV are the respective non-capacitance (F / g), the discharging current (A), the discharge time (s), by weight of the active material (g), and the discharge potential range (V) it means.

Referring to FIG. 7 (a), at the same current density of 1 A / g and a scan rate of 5 mV / s, an electrode using a mesoporous NiCo ₂ O ₄ nanoplate as an active material has a mesoporous structure of NiCo ₂ O _And exhibited a longer discharge time and higher current than electrodes using ₄ nanorods as the active material.

Referring to FIG. 7 (b), FIG. 7 (b) shows a Nyquist curve of a NiCo ₂ O ₄ nanorod and a nanoplate having a mesoporous structure. The impedance curve of the NiCo ₂ O ₄ electrode is 10 ⁵ Hz Was measured in a 6M KOH electrolyte with a frequency range of 0.01 Hz and a perturbation amplitude of 5 mV at 0.2 V vs. Ag / AgCl. It can be seen that the NiCo ₂ O ₄ nanowire has a more capacitive capacitance because it has a more nearly vertical curve in both low frequency and high frequency regions.

Referring to FIG. 7 (c), FIG. 7 (c) shows the mesoporous structure within a potential window between -0.1 and 0.5 V at various scan rates (2, 5, 10, and 20 mV / s) Of NiCo ₂ O ₄ nano-plate as an active material. The CV curve showed typical pseudo-capacitance characteristics of the active material with two pairs of redox peaks observed at a high scan rate of 20 mV / s. The oxidation reduction reaction is ² ⁺ Co / Co ⁺ ^3, Co ⁺ ³ / Co ⁴ ^+, and Ni ²⁺ / Ni ³⁺ will due to the switching, the electrode exhibited a low resistance and high pseudo-capacitance.

7 (d) is a graph showing the relationship between the current density (0.5, 1, 2, 4, 8 A / g) of the electrode using a NiCo ₂ O ₄ nanoparticle having a mesoporous structure as an active material electrochemical performance was also confirmed by galvanostatic charge-discharge tests performed at various current densities on electrodes using NiCo ₂ O ₄ nanoparticles as the active material . A high plateau charge / discharge curve consistent with the CV result suggests the presence of a faradaic process. Also, the fact that the IR drop was not observed in both charge / discharge curves indicates a rapid IV reaction of the electrode and excellent electrochemical reversibility.

7 (e) shows the constant current non-storage capacity retention rate of an electrode using mesoporous NiCo ₂ O ₄ nanorods and nano-plates as active materials at various current densities. NiCo ₂ O _In the case of using a _4- nano-plate as an electrode active material, the enhanced non-storage capacity increased by approximately 5 to 20% as compared with the case where the NiCo ₂ O ₄ nanorod is used as an electrode active material. The enhanced capacitive and speed capabilities can be attributed to the short ion diffusion path and the increased electron conductivity of the mesoporous NiCo ₂ O ₄ nanoparticles.

Referring to FIG. 7 (f), FIG. 7 (f) shows the charging / discharging times versus average non-storage capacity of the electrode using a NiCo ₂ O ₄ nanoplate having mesoporous structure as an active material at a current density of 4 A / As a result, an electrode using a mesoporous NiCo ₂ O ₄ nanoplate as an active material exhibited excellent stability in repetitive charge / discharge cycles. Even after the supercapacitor is charged and discharged 1500 times at a current density of 4 A / g, the supercapacitor maintains 95.3% of the initial capacity, and a NiCo ₂ O ₄ nanoplate having a mesoporous structure before and after 1500 charge / The impedance of the electrode used as an active material showed the most nearly vertical curve at a low frequency, indicating high capacitive behavior of the material and long-term electrochemical stability.

The electrode using the mesoporous NiCo ₂ O ₄ nano-plate as an active material exhibited a high non-storage capacity of 879 and 343 F / g at current densities of 0.5 and 20 A / g, respectively. Only 4.7% of the capacity was reduced, indicating excellent circulation stability. It has thus been found that the process is an easy, fast, efficient and environmentally friendly method for developing other materials for electrochemical capacitors.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Various modifications and variations are possible within the scope of the appended claims.

Claims

Dissolving the nickel precursor and the cobalt precursor in deionized water and an ionic liquid to form a mixture;
Adding oxalic acid and sodium hydroxide to the mixture, and stirring and dissolving the mixture;
Heating the mixture to which oxalic acid and sodium hydroxide have been added by irradiating microwave in a microwave reactor;
Cooling the nanostructured NiCo ₂ O ₄ nanostructure to a room temperature after the microwave irradiation, centrifuging the nanostructure, and washing and drying the separated NiCo ₂ O ₄ nanostructure; And
And firing the dried mesoporous NiCo ₂ O ₄ nanostructure,
The ionic liquid is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluoroborate methylimidazolium hexafluorophosphate), 1-ethyl-3-methylimidazolium tetrafluoroborate, and 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) (1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide). _{2. The} method according to claim _{1, wherein the} nanocomposite structure is selected from the group consisting of imide (1-butyl-3-methylimidazolium bis

The method of claim 1, wherein the nickel precursor is selected from the group consisting of nickel acetate tetrahydrate (Ni (CH ₃ COO) ₂ .4H ₂ O), nickel nitrate hexahydrate (Ni (NO ₃ ) ₂ .6H ₂ O) (NiCl ₂ .4H ₂ O), and the cobalt precursor is any one selected from the group consisting of cobalt acetate tetrahydrate (Co (CH ₃ COO) ₂ .4H ₂ O), cobalt nitrate hexahydrate _{Co (NO 3) 2 · 6H} 2 O), and cobalt chloride · 4-hydrate _{(CoCl 2 · 4H 2 O)} , NiCo 2 O of the mesopore structure, characterized in that any selected one from a group consisting of _four nanostructure manufacturing Way.

delete

The mesoporous NiCo ₂ O ₄ nanocomposite according to claim 1, characterized in that the microwave is irradiated by heating the mixture to which oxalic acid and sodium hydroxide have been added in a microwave reactor at 80 to 120 ° C for 5 to 20 minutes &Lt; / RTI >

The mesoporous structure according to claim 1, wherein the dried mesoporous NiCo ₂ O ₄ nanostructure is calcined at a temperature rising rate of 0.5 to 1.5 ° C / min for 1 to 3 hours at 250 to 350 ° C. Method for manufacturing NiCo ₂ O ₄ nanostructure.

2. The method of claim 1, wherein the mesoporous NiCo ₂ O ₄ nanostructure is a mesoporous NiCo ₂ O ₄ nanorod or Wherein the NiCo ₂ O ₄ nanocomposite structure is a NiCo ₂ O ₄ nanoplate having a mesopore structure.

A mesoporous NiCo ₂ O ₄ nanostructure produced by the method of any one of claims 1, 2, and 4 to 6.

The method according to claim 7, NiCo ₂ O ₄ in the mesoporous structure nanostructures supercapacitor electrode, a secondary battery electrode, catalyst, or the, mesopore structure, characterized in that the material of the sensor NiCo ₂ O ₄ nano structure.