Ni (OH) 2 ultrathin nanosheet synthesized by taking organic heterocyclic ring as template and preparation method of Ni (OH) 2 ultrathin nanosheet

Abstract

The invention discloses a preparation method of a Ni (OH) 2 ultrathin nanosheet synthesized by taking an organic heterocyclic ring as a template. The preparation method comprises the following steps: step 1, dissolving Ni salt into water to obtain a solution I; step 2, adding organic heterocyclic micromolecules into water to obtain a solution II; 3, mixing the solution I in the step 1 and the solution II in the step 2 to obtain a mixed solution III; step 4, transferring the uniform solution III obtained in the step 3 into a high-pressure reaction kettle to perform solvothermal reaction, and cooling after the reaction to obtain Ni (OH) 2 nanosheet turbid liquid; and step 5, separating, washing and drying the Ni (OH) 2 nanosheet suspension obtained in the step 4 to obtain the pure Ni (OH) 2 ultrathin nanosheet. Compared with the prior art, the preparation method has the advantages that the microstructure of the prepared nanosheet is a two-dimensional (2D) ultrathin nanosheet structure, and the nanosheet has excellent optical energy storage and electrochemical energy storage performance.

Description

Technical Field

[0001] The present invention relates to the technical field of material preparation and the technical field of energy storage, and specifically refers to a Ni(OH)2 ultra-thin nanosheet synthesized using an organic heterocycle as a template and a preparation method thereof. Background Art

[0002] Supercapacitors are a type of energy storage element developed in recent years that can store intermittent energy. They have the advantages of high energy density and power density, long energy storage life, and fast charging and discharging speed. They have the potential for wide application in the fields of energy storage and power supply.

[0003] Ni(OH)2 nanobelts are very sensitive to electron beam irradiation under high vacuum conditions and transform into a porous structure, indicating their potential application value in electrochemical performance. In addition, the nanostructure of Ni(OH)2 exhibits excellent electrochemical performance due to its large surface area and unique morphology, which is suitable for high energy density batteries.

[0004] In the current scientific research field and practical application exploration, Ni(OH)2, as a material with potentially important value, has shown good electrocatalytic activity, which makes it have broad application prospects in many fields, such as energy storage and catalytic reactions, and has attracted the attention and research of many scientific researchers. However, in the in-depth study and actual preparation of Ni(OH)2, we encountered many obstacles. First of all, from the perspective of material morphology synthesis, it is an extremely challenging task to obtain the ideal Ni(OH)2 morphology. Due to its complex crystal growth mechanism, it is affected by a combination of factors, such as reaction temperature, reactant concentration, reaction time, and solution pH. The interaction between these factors makes it extremely difficult to accurately control the morphology of Ni(OH)2.

[0005] In actual operation, it is often difficult to obtain a uniform, regular morphology that meets the requirements of specific applications, which not only limits the further optimization of its performance, but also brings considerable difficulties to large-scale industrial production. Secondly, the adjustment of the band gap structure of Ni(OH)2 is also a key issue that needs to be solved urgently. The band gap structure plays a decisive role in the electrical, optical and catalytic properties of the material. The appropriate band gap structure can significantly improve the performance of the material in related applications.

[0006] However, the current means of regulating the band gap structure of Ni(OH)2 are relatively limited, and the traditional methods are not ideal, making it difficult to achieve precise regulation of the band gap structure. This results in us being unable to fully utilize the potential advantages of Ni(OH)2 in practical applications and unable to meet the diverse demands for material performance in different fields. Summary of the invention

[0007] The technical problem to be solved by the present invention is to overcome the above technical defects and provide a Ni(OH)₂ ultrathin nanosheet synthesized with an organic heterocycle as a template and a preparation method therefor.

[0008] To solve the above technical problem, the technical solution provided by the present invention is: A preparation method of a Ni(OH)₂ ultrathin nanosheet synthesized with an organic heterocycle as a template, comprising the following steps:

[0009] Step 1. Dissolve a Ni salt in water to obtain Solution 1;

[0010] Step 2. Dissolve an organic heterocyclic small molecule in water to obtain Solution 2;

[0011] Step 3. Mix Solution 1 in Step 1 and Solution 2 in Step 2 to obtain a mixed solution, Mixed Solution 3;

[0012] Step 4. Transfer the homogeneous Mixed Solution 3 obtained in Step 3 to a high-pressure reaction kettle for solvothermal reaction, and cool after the reaction to obtain a Ni(OH)₂ nanosheet suspension;

[0013] Step 5. Separate, wash, and dry the Ni(OH)₂ nanosheet suspension in Step 4 to obtain pure Ni(OH)₂ ultrathin nanosheets.

[0014] Preferably, the Ni salt in Step 1 is one or a combination of several of nickel acetate, nickel nitrate, bis(triphenylphosphine) nickel chloride, nickel chloride hexahydrate.

[0015] Preferably, the organic heterocyclic small molecule in Step 2 is one or a combination of several of five-membered heterocycles or six-membered heterocycles.

[0016] Preferably, the preparation of the mixed solution, Mixed Solution 3 in Step 3 is obtained by any one of a constant pressure separating funnel, direct mixing, and ultrasonic mixing.

[0017] Preferably, in the solvothermal reaction in Step 4, the temperature of the solvothermal reaction is 100 - 220 °C, and the reaction time is 10 - 72 h.

[0018] Preferably, in Step 5, the drying temperature is 40 - 100 °C, and the time is 3 - 24 hours.

[0019] Preferably, the five-membered heterocycles in Step 2 include one or a combination of several of pyrrole, selenophene, thiophene, furan, and the six-membered heterocycles include one or a combination of several of piperidine, pyridine derivatives.

[0020] On the other hand, the present invention also discloses a Ni(OH)₂ ultrathin nanosheet synthesized with an organic heterocycle as a template, which has a two-dimensional ultrathin nanosheet structure and, as an electrode material for an energy storage device, has excellent photo energy storage and electrochemical energy storage properties.

[0021] The advantages of the present invention compared with the prior art are as follows: In the present invention, organic heterocyclic small molecules are used as soft templates, and the preparation operation is simple, the cost is low, the structural morphology of the material is controllable. The prepared nanosheets have a two-dimensional (2D) ultrathin nanosheet structure at the microscopic level, and have excellent photoenergy storage and electrochemical energy storage properties. The raw material preparation operation is simple, the cost is low, and it has strong economic application benefits. Description of the Drawings

[0022] Figure 1 It is the SEM image of the ultrathin nanosheet material of Example 1.

[0023] Figure 2 It is the ultraviolet absorption spectrum of the ultrathin nanosheet material of Example 1.

[0024] Figure 3 It is the cyclic voltammogram of the capacitance of the ultrathin nanosheet material of Example 1. Detailed Embodiments

[0025] The present invention will be further described in detail below with reference to the drawings.

[0026] Combined with the attached Figures 1-3 As shown,

[0027] It includes the following steps:

[0028] 1) Using organic heterocyclic small molecules as soft templates, different Ni salts are selected, and the ratio of Ni salt to organic heterocyclic molecules is regulated, and aqueous Ni salt solutions and aqueous organic small molecule heterocyclic solutions are respectively prepared.

[0029] 2) The aqueous Ni salt solution and the aqueous organic heterocyclic solution in step 1 are mixed into a homogeneous solution by the method of dropping while stirring, and reserved

[0030] 3) Transfer the homogeneous solution obtained in step 2 to a high-pressure reaction kettle, regulate the reaction temperature range and reaction time, and carry out a solvothermal reaction. After the reaction, it is cooled to obtain a Ni(OH)2 nanosheet suspension.

[0031] 4) Separate, wash, and dry the Ni(OH)2 nanosheet suspension in step 3 to obtain pure Ni(OH)2 ultrathin nanosheets for use.

[0032] In step 1), the Ni salt is any one of nickel acetate, nickel nitrate, bis(triphenylphosphine) nickel chloride, nickel chloride hexahydrate

[0033] In step 1), the organic heterocyclic small molecules are five-membered heterocycles such as pyrrole, selenophene, thiophene, and furan, and six-membered heterocycles such as piperidine, 4-methylpyridine, and 4-chloropiperidine.

[0034] In step 2), an aqueous nickel salt solution is added dropwise into the reaction vessel using a constant-pressure separatory funnel, and stirring is maintained continuously throughout the dropping process to ensure sufficient mixing and reaction of the materials.

[0035] In step 2), the conditions for the solvothermal reaction are that the temperature of the solvothermal reaction is 150 - 220 °C, and the solvothermal reaction time is 10 - 30 h.

[0036] In step 3), the temperature used in the drying process is 60 - 100 °C, and the time is 6 - 12 hours.

[0037] Example 1

[0038] (1) Dissolve 0.1246 g of nickel acetate tetrahydrate solid in 30 mL of deionized aqueous solution; at 40 °C in a water bath, take 69 μL of pyrrole solution and add it dropwise to 10 mL of deionized aqueous solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution using a constant-pressure separatory funnel. After the titration is completed, stir continuously for 30 minutes.

[0039] (2) Transfer the solution obtained in (1) to a 50 mL polytetrafluoroethylene-lined stainless steel autoclave for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed, when the solution cools to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0040] Example 2

[0041] (1) Dissolve 0.1246 g of nickel acetate tetrahydrate solid in 30 mL of deionized aqueous solution; at 40 °C in a water bath, take 79 μL of thiophene solution and add it dropwise to 10 mL of deionized aqueous solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution using a constant-pressure separatory funnel. After the titration is completed, stir continuously for 30 minutes.

[0042] (2) Transfer the solution obtained in (1) to a 50 mL polytetrafluoroethylene-lined stainless steel autoclave for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed, when the solution cools to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0043] Example 3

[0044] (1) Dissolve 0.1246 g of nickel acetate tetrahydrate solid in 30 mL of deionized aqueous solution; at 40 °C in a water bath, take 31 μL of selenophene solution and add it dropwise to 10 mL of deionized aqueous solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution using a constant-pressure separatory funnel. After the titration is completed, stir continuously for 30 minutes.

[0045] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a PTFE liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0046] Example 4

[0047] (1) Dissolve 0.1246 g of nickel acetate tetrahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 72 μL of furan solution and drop it into 10 mL of deionized water solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution using a constant pressure separating funnel. After the titration is completed, stir continuously for 30 minutes.

[0048] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a PTFE liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0049] Example 5

[0050] (1) Dissolve 0.1456 g of nickel nitrate hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 69 μL of pyrrole solution and drop it into 10 mL of deionized water solution at 40 °C and stir evenly. Then, titrate it into the nickel nitrate hexahydrate solution using a constant pressure separating funnel. After the titration is completed, stir continuously for 30 minutes.

[0051] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a PTFE liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0052] Example 6

[0053] (1) Dissolve 0.1456 g of nickel nitrate hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 79 μL of 4-methylpyridine solution and drop it into 10 mL of deionized water solution at 40 °C and stir evenly. Then, titrate it into the nickel nitrate hexahydrate solution using a constant pressure separating funnel. After the titration is completed, stir continuously for 30 minutes.

[0054] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a PTFE liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0055] Example 7

[0056] (1) Dissolve 0.1456 g of nickel nitrate hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 31 μL of 4-chloropiperidine solution and add it dropwise to 10 mL of deionized water solution at 40 °C and stir evenly. Titrate it into the nickel acetate tetrahydrate solution by the method of constant pressure dropping funnel. After the titration is completed, stir continuously for 30 minutes.

[0057] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a PTFE liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0058] Example 8

[0059] (1) Dissolve 0.1456 g of nickel nitrate hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 72 μL of furan solution and add it dropwise to 10 mL of deionized water solution at 40 °C and stir evenly. Titrate it into the nickel acetate tetrahydrate solution by the method of constant pressure dropping funnel. After the titration is completed, stir continuously for 30 minutes.

[0060] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a PTFE liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0061] Example 9

[0062] (1) Dissolve 0.1190 nickel chloride hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 69 μL of 4-chloropiperidine solution and add it dropwise to 10 mL of deionized water solution at 40 °C and stir evenly. Titrate it into the nickel acetate tetrahydrate solution by the method of constant pressure dropping funnel. After the titration is completed, stir continuously for 30 minutes.

[0063] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a Teflon liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0064] Example 10

[0065] (1) Dissolve 0.1190 g of nickel chloride hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 79 μL of thiophene solution and add it dropwise to 10 mL of deionized water solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution by means of a constant pressure burette. After the titration is completed, stir continuously for 30 minutes.

[0066] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a Teflon liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0067] Example 11

[0068] (1) Dissolve 0.1190 g of nickel chloride hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 31 μL of 4-methylpyridine solution and add it dropwise to 10 mL of deionized water solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution by means of a constant pressure burette. After the titration is completed, stir continuously for 30 minutes.

[0069] (2) Transfer the solution obtained in (1) to a 50 mL stainless steel autoclave with a Teflon liner for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed and the solution is cooled to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0070] Example 12

[0071] (1) Dissolve 0.1190 g of nickel chloride hexahydrate solid in 30 mL of deionized water solution; under a 40 °C water bath, take 72 μL of 4-methylpyridine solution and add it dropwise to 10 mL of deionized water solution at 40 °C and stir evenly. Then, titrate it into the nickel acetate tetrahydrate solution by means of a constant pressure burette. After the titration is completed, stir continuously for 30 minutes.

[0072] (2) Transfer the solution obtained in (1) to a 50 mL polytetrafluoroethylene-lined stainless steel autoclave for solvothermal reaction. React at 180 °C for 10 h. After the reaction is completed, cool the solution to room temperature, centrifuge for 10 minutes, collect the product, wash it with deionized water and ethanol, and finally dry the synthesized product at 60 °C for 24 h. Grind the obtained product and store it at room temperature.

[0073] The present invention and its embodiments have been described above. Such description is not restrictive. What is shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. In general, if those of ordinary skill in the art are inspired by it and, without departing from the gist of the present invention, design similar structural modes and embodiments to this technical solution without creative efforts, they shall fall within the protection scope of the present invention.

Claims

1. A method for preparing Ni(OH)2 ultrathin nanosheets synthesized using organic heterocycles as templates, characterized in that: The steps include: Step 1. Dissolve Ni salt in water to obtain solution 1; Step 2. Adding an organic heterocyclic small molecule to water to obtain a solution 2; Step 3. Mixing the solution 1 in step 1 and the solution 2 in step 2 to obtain a mixed solution 3; Step 4. The uniform solution obtained in step 3 is transferred to a high pressure reactor for solvothermal reaction, and cooled after the reaction to obtain a Ni(OH)2 nanosheet suspension; Step 5. Separate, wash and dry the Ni(OH)2 nanosheet suspension in step 4 to obtain pure Ni(OH)2 ultrathin nanosheets.

2. The method for preparing Ni(OH)2 ultra-thin nanosheets synthesized using organic heterocycles as templates according to claim 1, characterized in that: In step 1, the Ni salt is one or a combination of nickel acetate, nickel nitrate, bis(triphenylphosphine)nickel chloride, and nickel chloride hexahydrate.

3. The method for preparing Ni(OH)2 ultra-thin nanosheets synthesized using organic heterocycles as templates according to claim 1, characterized in that: In the step 2, the organic heterocyclic small molecule is one or a combination of five-membered heterocyclic rings or six-membered heterocyclic rings.

4. The method for preparing Ni(OH)2 ultra-thin nanosheets synthesized using organic heterocycles as templates according to claim 1, characterized in that: The mixed solution three in step 3 is prepared by using any of the following methods: a constant pressure separatory funnel, direct mixing, or ultrasonic mixing.

5. The method for preparing Ni(OH)2 ultra-thin nanosheets synthesized using organic heterocycles as templates according to claim 1, characterized in that: The temperature of the solvent thermal reaction in the solvent thermal reaction of step 4 is 100-220° C., and the reaction time is 10-72 hours.

6. The method for preparing Ni(OH)2 ultra-thin nanosheets synthesized using organic heterocycles as templates according to claim 1, characterized in that: In step 5, the drying temperature is 40-100° C. and the drying time is 3-24 hours.

7. The method for preparing Ni(OH)2 ultra-thin nanosheets synthesized using organic heterocycles as templates according to claim 3, characterized in that: In step 2, the five-membered heterocyclic ring includes one or a combination of pyrrole, selenophene, thiophene, and furan, and the six-membered heterocyclic ring includes one or a combination of piperidine and pyridine derivatives.

8. A Ni(OH)2 ultra-thin nanosheet synthesized using an organic heterocycle as a template, prepared by the method of any one of claims 1 to 7, characterized in that: It has a two-dimensional ultra-thin nanosheet structure.

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