CN113963954B - NHNO nano array, preparation method thereof and application of NHNO nano array in supercapacitor electrode - Google Patents

Abstract

The invention belongs to the field of nano-scale,the NHNO nano array and the preparation method thereof and the application of the NHNO nano array in a super capacitor electrode are disclosed. The invention controls Ni (OH) in the reaction system ₂ And HHTP is added to realize the control of the length and the density of the NHNO nano array. The metal organic framework NHNO nano array is obtained through the controllable synthesis method, has good supercapacitor performance, and has important significance in preparing the supercapacitor. Meanwhile, the synthesis method has the characteristics of simple process, low reaction temperature and short time, and is suitable for industrial batch production.

Description

A kind of NHNO nanometer array and preparation method thereof, and in supercapacitor electrode Applications

technical field

The invention belongs to the field of nanometers, and relates to an NHNO nanometer array, a preparation method thereof, and an application in supercapacitor electrodes.

Background technique

In recent years, due to population growth and rapid economic development, the growth in energy demand has become the driving force for the development of energy storage technology. Among all energy storage devices, supercapacitors have attracted widespread attention because of their higher cycle life, power density, faster redox reaction, environmental friendliness, and low cost. During the electrode reaction of supercapacitors, both the transport and storage of electrons take place in the electrolyte on or near the surface of the electrode material. Therefore, the microstructure of the electrode material is a key factor affecting the performance of the device. The metal-organic framework (MOF) material has the characteristics of simple synthesis method, high porosity, large specific surface area, neat and orderly internal structure, etc., and has great application prospects in the field of electrochemical energy storage.

Literature research shows that nickel hydroxide is a transition metal hydroxide that has been studied more. When nickel hydroxide is used as the active material of capacitors, the characteristics of good reversibility and fast reaction speed in the oxidation and reduction process of nickel hydroxide are used. In the past, there have been many studies on the doping modification of Ni(OH) ₂ , such as doping metal elements, rare earth elements, compound doping metal elements and metal elements, rare earth elements and metal elements. However, there are few reports on the in situ growth of metal-organic frameworks (MOFs) on the surface of Ni(OH) ₂ to synthesize nanoarrays. Therefore, it is very necessary to develop efficient synthesis methods of Ni-based nanoarrays with special structures, especially for supercapacitor electrode materials, which is of great significance and great challenge.

Contents of the invention

The purpose of the present invention is to disclose a kind of NHNO nano-array, its preparation method, and the application in the supercapacitor electrode.

The term "metal-organic framework structure" in the claims and description of the present invention means that the metal-organic framework material is self-assembled by metal ions or metal clusters and organic linking ligands through coordination bonds.

The term "supercapacitor" refers to a new type of energy storage device between traditional capacitors and rechargeable batteries. It has both the characteristics of fast charge and discharge of capacitors and the energy storage characteristics of batteries.

The term "pseudocapacitance" refers to a two-dimensional or quasi-two-dimensional space on the surface of the electrode or in the bulk phase, underpotential deposition of electroactive substances, highly reversible chemical adsorption, desorption or oxidation, reduction reactions, generation and Capacitance related to electrode charging potential.

An object of the present invention is to disclose an NHNO nano-array, which is achieved through the following technical solutions.

A NHNO nanoarray with Ni-HHTP grown in situ on Ni(OH) ₂ hexagonal sheets,

Wherein, the Ni-HHTP is a metal organic framework structure.

Further, the thickness of the Ni(OH) ₂ hexagonal sheet is 40±3nm, belonging to the nanometer level, and the large specific surface area is conducive to the transmission of ions. ,

Further, the length of the NHNO nano-array is 74-115nm.

Another object of the present invention is to disclose the preparation method of the above-mentioned NHNO nanoarray, comprising the following steps:

S1. Using Ni(OH) ₂ hexagonal tablets and Ni(CH ₃ COO) ₂ aqueous solution as raw materials, ultrasonic reaction to obtain intermediate product 1;

S2. Adding HHTP into H ₂ O, and ultrasonically reacting to obtain intermediate product 2;

S3. Blending the intermediate product 1 and the intermediate product 2, and heating and reacting to obtain the NHNO nano-array.

Further, the mass ratio of Ni(CH ₃ COO) ₂ to Ni(OH) ₂ is 1:1-1:2.

Further, the mass ratio of Ni(OH) ₂ to HHTP is 1:1-4:1, because if there is too much Ni(OH) ₂ , HHTP will not be able to grow completely on the surface of Ni(OH) ₂ .

Further, in step S3, the heating reaction temperature is gradually increased at a rate of 2-4 ^° C/min. The heating reaction temperature rise rate is slower, which is conducive to a more complete reaction. If the heating rate is too fast, the structure of HHTP will be destroyed.

Further, in step S3, the heating reaction time is 10-15 h.

Further, the ultrasonic reaction time is 5-35 min, which is conducive to full contact between Ni(OH) ₂ and HHTP. Another object of the present invention is to disclose the application of the above-mentioned NHNO nano-array in supercapacitor electrodes.

The beneficial effects of the present invention are as follows:

1. The NHNO nanoarray prepared by the present invention has excellent supercapacitor performance, can charge and discharge quickly, that is, store electric energy efficiently, and has important guiding significance for the development of renewable energy technology.

2. the NHNO nano-arrays involved in the present invention can be synthesized under lower temperature conditions, and can be utilized to change the mass ratio of Ni(OH) ₂ and the amount of HHTP added to easily control the morphology of the NHNO nano-arrays; in addition It also has the advantages of simple process, short time and suitable for mass production.

Description of drawings

Figure 1 shows TEM images of various materials;

in,

Figure 1(a) is the surface diagram of Ni(OH) ₂ hexagonal sheet;

Fig. 1 (b) is the NHNO nanometer array surface figure that embodiment 1 prepares;

Fig. 1 (c) is the NHNO nano-array surface figure that embodiment 2 prepares;

FIG. 1( d ) is a surface view of the NHNO nanoarray prepared in Example 3.

Fig. 2 shows the NHNO nano-array supercapacitor performance test figure prepared by embodiment 1;

in,

Figure 2(a) shows the linear sweep voltammetry (CV) curve of the NHNO nanoarray;

Figure 2(b) shows the lateral flow charge-discharge (GCD) curves of NHNO nanoarrays.

Fig. 3 shows the NHNO nano-array supercapacitor performance test figure prepared by embodiment 2;

in,

Figure 3(a) shows the linear sweep voltammetry (CV) curves of NHNO nanoarrays;

Figure 3(b) shows the lateral flow charge-discharge (GCD) curves of NHNO nanoarrays.

Fig. 4 shows the NHNO nano-array supercapacitor performance test figure prepared by embodiment 3;

in,

Figure 4(a) shows the linear sweep voltammetry (CV) curves of NHNO nanoarrays;

Figure 4(b) shows the lateral flow charge-discharge (GCD) curves of NHNO nanoarrays.

detailed description

In order to illustrate the technical solutions of the present invention more clearly, the following examples are listed, but the present invention is not limited thereto.

The experimental methods used in the following examples are conventional methods unless otherwise specified; the reagents and materials used in the following examples can be obtained from commercial sources unless otherwise specified.

Example 1

A kind of NHNO nano-array, described NHNO nano-array grows Ni-HHTP in situ on Ni(OH)2 hexagonal sheets,

Wherein, the Ni-HHTP is a metal organic framework structure.

The preparation method of the above-mentioned NHNO nano-array comprises the following steps:

S1. At room temperature, weigh 5 mg of Ni(OH) ₂ hexagonal tablet, pour it into 2 mL of Ni(CH ₃ COO) ₂ aqueous solution (5 mg/mL), and sonicate for 30 min to obtain intermediate product 1;

S2. Weigh 5 mg of HHTP and pour it into 2 mL of deionized water, sonicate for 5 min to obtain intermediate product 2;

S3. Pour the intermediate product obtained in S1 and S2 into a 10 mL reagent glass bottle. Put it into a muffle furnace, gradually increase the temperature at a rate of 2 °C/min, and react at 85 °C for 12 h. After the reaction was completed, the temperature was lowered to room temperature, a sufficient amount of deionized water and acetone were added for dispersion, and the solid was separated by centrifugation. After the solid was washed, the solid turned blue-black, and the solid was dried at room temperature overnight for analysis and characterization.

Figure 1(a) shows the transmission electron microscope (TEM) detection image of the Ni(OH) ₂ hexagonal plate used in the present invention, the thickness of which is 40 nm.

Figure 1(b) shows the transmission electron microscope (TEM) detection image of the product of Example 1, which shows that the prepared NHNO nano-arrays are relatively dense, and the length of the array is about 115 nm.

Example 2

A kind of NHNO nano-array, it is characterized in that, described NHNO nano-array is on Ni(OH) 2 hexagonal sheets grow Ni-HHTP in situ,

Wherein, the Ni-HHTP is a metal organic framework structure.

The preparation method of the above-mentioned NHNO nano-array comprises the following steps:

S1. At room temperature, weigh 5 mg of Ni(OH) ₂ hexagonal tablet, pour it into 2 mL of Ni(CH ₃ COO) ₂ aqueous solution (5 mg/mL), and sonicate for 30 min to obtain intermediate product 1;

S2. Weigh 2.5 mg of HHTP and pour it into 2 mL of deionized water, sonicate for 5 min to obtain intermediate product 2;

S3. Pour the intermediate product obtained in S1 and S2 into a 10 mL reagent glass bottle. Put it into a muffle furnace, gradually increase the temperature at a rate of 2 °C/min, and react at 85 °C for 12 h. After the reaction was completed, the temperature was lowered to room temperature, a sufficient amount of deionized water and acetone were added for dispersion, and the solid was separated by centrifugation. After the solid was washed, the solid turned blue-black, and the solid was dried at room temperature overnight for analysis and characterization.

Figure 1(c) shows the transmission electron microscope (TEM) detection image of the product of Example 2, which shows that the prepared NHNO nanoarray is relatively sparse, and the array becomes shorter, about 85 nm.

Example 3

A kind of NHNO nano-array, it is characterized in that, described NHNO nano-array is on Ni(OH) 2 hexagonal sheets grow Ni-HHTP in situ,

Wherein, the Ni-HHTP is a metal organic framework structure.

The preparation method of the above-mentioned NHNO nano-array comprises the following steps:

S1. At room temperature, weigh 10 mg of Ni(OH) ₂ hexagonal tablet, pour it into 2 mL of Ni(CH ₃ COO) ₂ aqueous solution (5 mg/mL), and sonicate for 30 min to obtain intermediate product 1;

S2. Weigh 2.5 mg of HHTP and pour it into 2 mL of deionized water, sonicate for 5 min to obtain intermediate product 2;

S3. Pour the intermediate product obtained in S1 and S2 into a 10 mL reagent glass bottle. Put it into a muffle furnace, gradually increase the temperature at a rate of 2 °C/min, and react at 85 °C for 12 h. After the reaction was completed, the temperature was lowered to room temperature, a sufficient amount of deionized water and acetone were added for dispersion, and the solid was separated by centrifugation. After the solid was washed, the solid turned blue-black, and the solid was dried at room temperature overnight for analysis and characterization.

Figure 1(d) shows the transmission electron microscope (TEM) detection image of the product of Example 3, which shows that the prepared NHNO nanoarray is relatively sparse, and the array is short, about 74 nm.

test case 1

In the three-electrode system, by cyclic voltammetry and constant current charge-discharge method, test the electrochemical properties of the sample of Example 1 for supercapacitor electrodes, the specific process is as follows:

The electrochemical experiment was carried out on a CHI760e electrochemical workstation, using a standard three-electrode test system, and the corresponding working electrode was the nickel foam electrode modified by the samples obtained in this paper. The counter electrode is platinum wire and the reference electrode is mercury/mercury oxide (Hg/HgO). All potentials herein are relative to mercury/mercury oxide. The electrolyte is a 3 M KOH solution. All electrochemical tests were performed at 23 ^° C. All electrodes were tested in 3 M KOH solution for each experiment.

The preparation method of sample modified nickel foam is as follows:

Cut the nickel foam into a size of 1 cm × 5 cm, ultrasonically clean it with deionized water for 30 min, then ultrasonically clean it with ethanol for 30 min, and dry it at 65 ^o C for 3 h before use.

Take 8 mg of the NHNO nanoarray prepared in Example 1 and 0.15 mg of acetylene black, and grind them with a mortar for 15 min. Add an appropriate amount of isopropanol and continue grinding for 15 min. Add 1-2 drops of polytetrafluoroethylene (PTFE) emulsion, stir and drop on the surface of nickel foam to be used. Overnight at room temperature, awaiting electrochemical tests.

The modified nickel foam samples were subjected to cyclic voltammetry and galvanostatic charge-discharge tests in the above-mentioned three-electrode system.

FIG. 2 is a performance test diagram of the NHNO nano-array supercapacitor prepared in Example 1. FIG. Among them, Figure 2(a) shows a redox peak at 0.4 V, indicating that this material has pseudocapacitor activity. Calculated by Fig. 2(b), the specific capacitance of NHNO nanoarrays is 127 F/g when the current density is 1 A/g, 2 A/g, 3 A/g, 4 A/g and 5 A/g g, 110 F/g, 90 F/g, 76 F/g, and 80 F/g. The test results show that the NHNO nanoarrays exhibit better supercapacitor performance.

test case 2

Compared with Test Example 1, the difference of this Test Example is only that: 8 mg of the NHNO nanoarray prepared in Example 2 was used instead of the NHNO nanoarray prepared in Example 1.

FIG. 3 is a performance test diagram of the NHNO nano-array supercapacitor prepared in Example 2. Among them, Figure 3(a) shows a redox peak at 0.4 V, indicating that this material has pseudocapacitor activity. Calculated by Fig. 3(b), the specific capacitance of NHNO nanoarrays at current densities of 0.5 A/g, 1 A/g, 2 A/g, 3 A/g, 4 A/g and 5 A/g 289 F/g, 248 F/g, 222 F/g, 198 F/g, 180 F/g, and 175 F/g, respectively. The test results show that the NHNO nanoarrays exhibit better supercapacitor performance.

Test case 3

Compared with Test Example 1, the difference of this Test Example is only that: 8 mg of the NHNO nanoarray prepared in Example 3 was used instead of the NHNO nanoarray prepared in Example 1.

FIG. 4 is a performance test chart of the NHNO nano-array supercapacitor prepared in Example 3. Among them, Figure 4(a) shows a redox peak at 0.4 V, indicating that this material has pseudocapacitor activity. Calculated by Fig. 4(b), the specific capacitance of the NHNO nanoarray is 105 F/g, 97 F/g, 86 F/g, 78 F/g, 68 F/g, and 70 F/g, respectively. The test results show that the NHNO nanoarrays exhibit better supercapacitor performance.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only includes an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (9)

1. A kind of NHNO nano-array, it is characterized in that, described NHNO nano-array is on Ni(OH) On the hexagonal plate, Ni-HHTP is grown in situ, and wherein, described Ni-HHTP is metal-organic framework structure; The preparation method of described NHNO nanometer array, comprises the following steps: S1. Using Ni(OH)2 hexagonal tablets and Ni(CH3COO)2 aqueous solution as raw materials, ultrasonic reaction to obtain intermediate product 1; S2. Adding HHTP to H2O, ultrasonically reacting to obtain intermediate product 2; S3. Blend the intermediate product 1 and the intermediate product 2, heat the reaction, and wash and settle to obtain the NHNO nano-array. 2. A kind of NHNO nano-array according to claim 1, characterized in that, the thickness of the Ni(OH)2 hexagonal plate is 40±3nm. 3. A kind of NHNO nano-array according to claim 1, characterized in that, the length of the NHNO nano-array is 74-115 nm. 4. A kind of NHNO nano-array according to claim 1, characterized in that, the mass ratio of Ni(OH)2Ni(CH3COO)2 added is 1:1-1:2. 5. A kind of NHNO nanoarray according to claim 1, is characterized in that, Ni(OH) The mass ratio of the addition amount of HHTP is 1:1-4:1. 6. A kind of NHNO nano-array according to claim 1, is characterized in that, in step S3, in described heating reaction, temperature carries out gradual warming according to the rate of 2-4 C/min. 7. A kind of NHNO nano-array according to claim 1, characterized in that, in step S3, the heating reaction time is 10-15 h. 8. A kind of NHNO nano-array according to claim 4, it is characterized in that, the ultrasonic reaction time is 5-35min. 9. The application of the NHNO nano-array described in any one of claims 1-8 in supercapacitor electrodes.

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