Preparation method and application of CeO2 composite vacancy-rich Sv-NiCo-SxOHy layered flexible electrode material

Abstract

The invention belongs to the technical field of composite electrode materials, and relates to a preparation method of a CeO2-induced composite vacancy-rich Sv-NiCo-SxOHy layered flexible electrode material, which comprises the following steps: soaking ZIF-L / CC in a Lewis acid Ni ion aqueous solution for in-situ self-deposition reaction, washing and drying to obtain a layered electrode NiCo-LDH / CC; and continuously immersing into an ethanol solution containing a sulfur source, transferring into a reaction kettle for solvothermal reaction, naturally cooling, taking out, washing with deionized water and absolute ethyl alcohol for multiple times, drying at 60 DEG C to obtain a sulfur-coated layered electrode S-NiCo-LDH / CC, mixing the sulfur-coated layered electrode S-NiCo-LDH / CC with cerium salt and HMT, reacting in a high-pressure kettle at 160-200 DEG C for 4-8 hours, washing with deionized water, and drying to obtain the sulfur-coated layered electrode S-NiCo-LDH / CC. In-situ growth of CeO2 nanoparticles is utilized to enhance interface charge transfer, alkali-assisted high-temperature preparation of sulfur vacancies and doped sulfur synergistically widen a conductive network, and volume deformation is relieved through an interlayer confinement effect; when the obtained material is applied to a positive electrode of a supercapacitor, the self-supporting material avoids the use of an adhesive, the impedance of the material is reduced, and the electrochemical performance of the electrode is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite electrode materials, relates to flexible electrodes, and particularly relates to a preparation method and application of a CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material. Background Art

[0002] With the rapid development of portable electronic devices and renewable energy technologies, high-performance hybrid supercapacitors (HSCs) have become a research hotspot due to their environmental friendliness and safety. However, compared with traditional batteries, their insufficient energy density severely limits their practical applications, and the performance of electrode materials directly determines the energy storage capacity. Currently, nickel-cobalt layered double hydroxides (NiCo-LDHs) have a high theoretical specific capacitance (>2000 F g -1 ), and rich redox activity, but problems such as their poor intrinsic conductivity and low cycle stability caused by volume expansion during charge and discharge restrict their application in HSCs.

[0003] Existing improvement strategies include constructing heterojunctions or composites with carbon materials to enhance conductivity, but the effects are limited. Recent studies have shown that introducing CeO 2 can optimize the interfacial electronic structure through its unique 4f electron characteristics, realize the dynamic electron redistribution of the Ce 3+ / Ce 4+ redox pair, and significantly improve the catalytic activity of the material; at the same time, sulfur doping can further adjust the electron transport path and increase active sites. However, existing research has not explored the strategy of in-situ coating of sulfur doping and CeO 2 simultaneously introduced into NiCo-LDH, and it is difficult to balance the coupling effects of high conductivity, structural stability, and multiple active sites. Summary of the Invention

[0004] Aiming at the deficiencies existing in the above-mentioned prior art, an object of the present invention is to disclose a preparation method of a CeO 2 induced and composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material.

[0005] Technical Solution

[0006] Using cobalt salts, nickel salts, cerium salts, 2-methylimidazole (C 4 H 6 N 2 ), a sulfur source, hexamethylenetetramine (HMT, C 6 H 12 N4 ), using it as a raw material, first prepare ZIF-L / CC (carbon cloth) by in-situ self-deposition method, then obtain NiCo-LDH / CC material through rapid Lewis acid exchange / etching method, then prepare sulfur-coated electrode S-NiCo-LDH / CC by solvothermal method, and finally perform alkali-assisted high-temperature hydrothermal treatment of cerium oxide to obtain CeO 2 @S v -NiCo-S x OH y / CC flexible electrode material.

[0007] A kind of CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y (CeO 2 @S v -NiCo-S x OH y / CC) layered flexible electrode material preparation method, including the following steps:

[0008] A. Immerse ZIF-L / CC in an aqueous solution of Lewis acid Ni ions for in-situ self-deposition reaction for 1-12 h, preferably 4 h. After washing and drying, obtain layered electrode NiCo-LDH / CC; wherein, the material ratio of the ZIF-L array composite on carbon cloth (CC) to the aqueous solution of Lewis acid Ni ions is 1-3 mg: 5-15 mL, preferably 1.5 mg: 10 mL;

[0009] B. Immerse the layered electrode NiCo-LDH / CC in an ethanol solution containing a sulfur source, transfer it to a reaction kettle and react at 100-140 °C for 4-8 h, preferably react at 120 °C for 6 h. After the reaction kettle naturally cools to room temperature, take it out, wash it several times with deionized water and absolute ethanol, and dry it at 60 °C to obtain a sulfur-coated layered electrode S-NiCo-LDH / CC, wherein, the material ratio of NiCo-LDH, sulfur source, and ethanol in the layered electrode is 1-3 mg: 50-150 mg: 10-40 mL, preferably 1.5 mg: 100 mg: 25 mL;

[0010] C. Mix the sulfur-coated layered electrode S-NiCo-LDH / CC, cerium salt and hexamethylenetetramine (HMT), and react in a high-pressure kettle at 160-200 °C for 4-8 h, preferably react at 180 °C for 6 h. Wash the obtained product with deionized water and dry it to obtain CeO 2 @S v -NiCo-S x OH y / CC, wherein the material ratio of S-NiCo-LDH, cerium salt and HMT in the layered electrode is 1-3 mg: 0.01-0.10 mol: 0.1-0.3 mol, preferably 1.5 mg: 0.05 mol: 0.15 mol.

[0011] In a preferred disclosed example of the present invention, in step A, the ZIF-L / CC is prepared by mixing an aqueous solution of cobalt salt-deionized water and an aqueous solution of 2-methylimidazole-deionized water in equal volume, stirring evenly, and placing the carbon cloth CC (1×1 cm 2 ) in the mixed solution, standing for 10 h, washing, and drying at 60 °C. Among them, the aqueous solution of cobalt salt-deionized water is prepared by mixing cobalt salt and deionized water at a ratio of 1-3 mmol: 15-45 mL, preferably 1.5 mmol: 30 mL. The cobalt salt is Co(NO 3 ) 2 or CoCl 2 , preferably Co(NO 3 ) 2 ; the aqueous solution of 2-methylimidazole-deionized water is prepared by mixing 2-methylimidazole and deionized water at a ratio of 10-15 mmol: 15-45 mL, preferably 12 mmol: 30 mL.

[0012] In a preferred disclosed example of the present invention, in step A, the aqueous solution of Lewis acid Ni ions is prepared by dissolving nickel salt in deionized water according to a ratio of 10-30 mg: 5-15 mL, preferably 20 mg: 10 mL. Among them, the nickel salt is Ni(NO 3 ) 2 or NiCl 2 , preferably Ni(NO 3 ) 2 .

[0013] In a preferred disclosed example of the present invention, in step B, the ethanol solution containing a sulfur source is prepared by mixing a sulfur source and ethanol at a ratio of 50-150 mg: 10-40 mL to form an ethanol solution, preferably 100 mg: 25 mL. Among them, the sulfur source is thioacetamide (TAA) or sodium sulfide (Na 2 S), preferably TAA.

[0014] In a preferred disclosed example of the present invention, in step C, the cerium salt is Ce(NO 3 ) 3 or CeCl 3 , preferably Ce(NO 3 ) 3 .

[0015] According to the method of the present invention, the prepared CeO 2 induced composite rich vacancy S v -NiCo-Sx OH y (CeO 2 @S v -NiCo-S x OH y / (CC) layer flexible electrode material can be cut, bent and manipulated at will according to the actual situation. At the microscopic state, CeO 2 particles and S v -NiCo-S x OH y layered network are compounded together.

[0016] Another object of the present invention is to use the prepared CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y (CeO 2 @S v -NiCo-S x OH y / (CC) layer flexible electrode material as the positive electrode of a supercapacitor.

[0017] Specifically, the prepared CeO 2 @S v -NiCo-S x OH y / (CC) flexible electrode material as the positive electrode, using 6 mol / L -1 KOH as the electrolyte. Activated carbon, conductive carbon black and binder are uniformly mixed and dispersed in N-methylpyrrolidone solution in a mass ratio of 8:1:1, and then coated on nickel foam, dried and pressed into tablets to prepare electrode sheets as the electrode materials of the capacitor. Cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) and other electrochemical performance tests are carried out in a two-electrode system, and the corresponding energy density and power density are calculated to evaluate the electrochemical performance of the prepared CeO 2 @S v -NiCo-S x OH y / (CC) flexible electrode material. The voltage range of the cyclic voltammetry (CV) test is 0 to 0.5 V, and the scanning speeds are 2, 5, 10, 20, 50 and 100 mV s -1 , and the voltage range of the galvanostatic charge-discharge test is 0 to 0.5 V, and the current densities are 1, 2, 3, 5, 8 and 10 A g -1 .

[0018] The prepared CeO 2 @S v -NiCo-S x OHy The CC-layered flexible electrode material uses instruments such as field emission scanning electron microscopy (SEM), X-ray diffractometer (XRD), and CHI-760E electrochemical workstation to analyze the structure and performance of the product to evaluate its electrochemical activity.

[0019] LDH has a unique two-dimensional structure, a high specific surface area, adjustable functionalized surface terminals, good electrical conductivity, and high electrochemical activity. Especially when combined with sulfur with a large electronegativity, the electrochemical performance of the material can be greatly improved after being compounded with rare earth metal oxides in a high valence state.

[0020] In this invention, through the steps of room-temperature in-situ self-deposition - room-temperature Lewis acid exchange / etching - solvothermal sulfur coating - alkali-assisted high-temperature hydrothermal synthesis, a flexible composite electrode CeO with a hierarchical structure porous rich in vacancies and a high specific surface area is constructed on the surface of carbon cloth (CC). 2 @S v -NiCo-S x OH y / CC. The material uses the in-situ growth of CeO nanoparticles to strengthen the interfacial charge transfer. During the synthesis process, alkali-assisted high-temperature manufacturing of sulfur vacancies (S) and doped sulfur synergistically broaden the conductive network, and the volume deformation is alleviated through the interlayer confinement effect. Experiments show that this material exhibits an ultra-high specific capacitance (>3300 F g), excellent rate performance (90% capacity retention @ 10 A g), and long cycle life (>20000 times), significantly superior to single-component systems, providing an ideal electrode solution for a new generation of high-energy density HSC and flexible energy storage devices. 2 nanoparticles to strengthen the interfacial charge transfer. During the synthesis process, alkali-assisted high-temperature manufacturing of sulfur vacancies (S) and doped sulfur synergistically broaden the conductive network, and the volume deformation is alleviated through the interlayer confinement effect. Experiments show that this material exhibits an ultra-high specific capacitance (>3300 F g), excellent rate performance (90% capacity retention @ 10 A g), and long cycle life (>20000 times), significantly superior to single-component systems, providing an ideal electrode solution for a new generation of high-energy density HSC and flexible energy storage devices. v ), excellent rate performance (90% capacity retention @ 10 A g), and long cycle life (>20000 times), significantly superior to single-component systems, providing an ideal electrode solution for a new generation of high-energy density HSC and flexible energy storage devices. -1 ), excellent rate performance (90% capacity retention @ 10 A g), and long cycle life (>20000 times), significantly superior to single-component systems, providing an ideal electrode solution for a new generation of high-energy density HSC and flexible energy storage devices. -1 ), and long cycle life (>20000 times), significantly superior to single-component systems, providing an ideal electrode solution for a new generation of high-energy density HSC and flexible energy storage devices.

[0021] The reactant reagents used in this invention are cobalt salt (Co(NO 3 )) 2 ·6H 2 O), nickel salt (Ni(NO 3 )) 2 ·6H 2 O), cerium salt (Ce(NO 3 )) 3 ·9H 2 O), cerium salt (CeCl 3 ), 2-methylimidazole (C 4 H 6 N 2 ), thioacetamide (TAA, C 2 H 5 NS), sodium sulfide (Na 2 S), hexamethylenetetramine (HMT, C 6 H 12 N4 ), etc. are all commercially available.

[0022] Beneficial effects

[0023] Through the in-situ self-deposition method, solvothermal method and alkali-assisted hydrothermal method, CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material is synthesized. CC and the framework derived from ZIF-L jointly provide a flexible substrate for the self-supporting material, increasing the conductivity and specific surface area of the material. At the same time, CeO 2 and S v and others are intercalated into the LDH, adjusting the electronic structure and also playing an intermediate buffering role to prevent the volume expansion of the LDH and making its structure more stable. In addition, when applied as the positive electrode material of a supercapacitor, the self-supporting material avoids the use of adhesives, reduces the impedance of the material, and greatly improves the electrochemical performance of the material. Description of the drawings

[0024] Figure 1 . Scanning electron microscope image (a) and elemental mapping image (b) of the CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material prepared in Example 1;

[0025] Figure 2 . GCD curve of the CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material prepared in Example 1;

[0026] Figure 3 . Energy density-power density diagram of the supercapacitor assembled with the CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material prepared in Example 1;

[0027] Figure 4 . Cyclic stability diagram of the supercapacitor assembled with the CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material prepared in Example 1. Detailed implementation manners

[0028] The present invention will be described in detail below in conjunction with embodiments, so that those skilled in the art can better understand the present invention. However, the present invention is not limited to the following embodiments. Unless otherwise defined, the terms (including scientific and technical terms) used herein should be interpreted as having the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. It will also be understood that the terms used herein should be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art, and should not be interpreted in an idealized or excessive form unless specifically so defined herein.

[0029] Example 1

[0030] A method for preparing a CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material, comprising the following steps:

[0031] Step 1: Weigh 1.5 mmol of Co(NO 3 ) 2 ·6H 2 O and 12 mmol of 2-methylimidazole are separately dissolved in 30 mL of deionized water. The Co(NO 3 ) 2 deionized aqueous solution is mixed with the 2-methylimidazole solution and stirred for 5 minutes. Carbon cloth CC (1×1 cm 2 ) is placed in the mixed solution. After in-situ self-deposition reaction at room temperature for 10 hours, it is centrifuged and dried at 60 °C to obtain a ZIF-L nanoarray composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 and dissolve it in 10 mL of deionized water. Perform Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain a layered electrode NiCo-LDH / CC;

[0032] Step 2: Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution and react at 120 °C for 6 h. After the reaction kettle cools to room temperature, take out the sample, wash the sample several times with deionized water and absolute ethanol, and dry at 60 °C to obtain an S-NiCo-LDH / CC electrode;

[0033] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3 and mix with the S-NiCo-LDH / CC electrode in an autoclave and react at 180 °C for 6 h. The obtained substance is washed with deionized water and dried to obtain CeO 2 @S v-NiCo-S x OH y / CC flexible composite electrode material.

[0034] CeO 2 @S v -NiCo-S x OH y Characterization and analysis of CeO

[0035] As Figure 1 shown, it can be seen from the figure that in the microscopic state, CeO 2 nanoparticles are interspersed in the cross-linked layered material S v -NiCo-S x OH y , with a hierarchical composite structure and a super-high specific surface area.

[0036] As Figure 2 shown, it can be seen from the figure that the GCD curve of the CeO 2 @S v -NiCo-S x OH y / CC flexible composite material can be calculated to have a high specific capacitance of 3306 F g -1 at a current density of 1 A g -1 .

[0037] As Figure 3 shown, for the application of the CeO 2 @S v -NiCo-S x OH y / CC flexible composite material prepared in this example as a supercapacitor electrode material in a two-electrode system, it can be seen from the energy density-power density figure that the assembled supercapacitor has good power density and energy density. When its power density is 800 W kg -1 , the maximum energy density that can be achieved is 72.2 Wh kg -1 .

[0038] As Figure 4 shown, for the result of the cyclic stability test of the CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material used as the positive electrode material of the supercapacitor, after 20,000 cycles, it has a capacity retention rate of 115%, showing good cyclic performance.

[0039] Example 2

[0040] A method for preparing a CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material, comprising the following steps:

[0041] Step 1: Weigh 1.5 mmol of Co(NO 3 ) 2 ·6H 2 O and 12 mmol of 2-methylimidazole and dissolve them separately in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized water solution with the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60 °C to obtain a ZIF-L nanoarray composite on CC; Weigh 10 mg of Ni(NO 3 ) 2 and dissolve it in 10 mL of deionized water. Carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain a layered electrode NiCo-LDH / CC;

[0042] Step 2: Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120 °C for 6 h, take out the sample after the reaction kettle cools to room temperature, wash the sample several times with deionized water and absolute ethanol, and dry at 60 °C to obtain an S-NiCo-LDH / CC flexible electrode;

[0043] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3, then mix with the S-NiCo-LDH / CC electrode and react in an autoclave at 180 °C for 6 h. Wash the obtained substance with deionized water and dry to obtain a CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0044] The prepared CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material is used as the positive electrode material of a supercapacitor for cyclic stability testing. After 10,000 cycles, it has a capacity retention rate of 85.6%, showing good cyclic performance.

[0045] Example 3

[0046] A kind of CeO 2 Induced composite rich-vacancy S v -NiCo-S x OH y Preparation method of layered flexible electrode material, comprising the following steps:

[0047] Step 1, Weigh 1.5 mmol Co(NO 3 ) 2 ·6H 2 O and 12 mmol 2-methylimidazole, dissolve them separately with 30 mL deionized water, mix the Co(NO 3 ) 2 deionized water solution and 2-methylimidazole solution, stir for 5 minutes, place carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, dry at 60°C to obtain ZIF-L nanoarray composite on CC; Weigh 30 mg Ni(NO 3 ) 2 dissolve it in 10 mL deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain layered electrode NiCo-LDH / CC;

[0048] Step 2, Weigh 100 mg TAA and dissolve it in 25 mL ethanol, immerse the prepared NiCo-LDH / CC electrode into the above solution, react at 120°C for 6 h, take out the sample after the reaction kettle cools to room temperature, wash the sample several times with deionized water and absolute ethanol, dry at 60°C to obtain S-NiCo-LDH / CC flexible electrode;

[0049] Step 3, Mix Ce(NO 3 ) 3 and HMT according to a molar ratio of 1:3, mix with the S-NiCo-LDH / CC electrode, react in an autoclave at 180°C for 6 h, wash the obtained substance with deionized water, dry to obtain CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0050] The prepared CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material is used as the positive electrode material of a supercapacitor for cyclic stability test results. After 10,000 cycles, it has a capacity retention rate of 80.3%, showing good cyclic performance.

[0051] Example 4

[0052] A kind of CeO 2 Induced composite rich-vacancy S v -NiCo-S x OH y Preparation method of a layered flexible electrode material, comprising the following steps:

[0053] Step 1: Weigh 1.5 mmol Co(NO 3 ) 2 ·6H 2 O and 12 mmol 2-methylimidazole are respectively dissolved in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized water solution with the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution. After in-situ self-deposition reaction at room temperature for 10 hours, centrifuge and dry at 60°C to obtain a ZIF-L nanoarray composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, and perform Lewis acid ion exchange and etching at room temperature for 4 h. After washing and drying, obtain a layered electrode NiCo-LDH / CC;

[0054] Step 2: Weigh 50 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution and react at 120°C for 6 h. After the reaction kettle cools to room temperature, take out the sample, wash the sample several times with deionized water and absolute ethanol, and dry at 60°C to obtain an S-NiCo-LDH / CC flexible electrode;

[0055] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3 and mix them with the S-NiCo-LDH / CC electrode in an autoclave and react at 180°C for 6 h. Wash the obtained substance with deionized water and dry to obtain CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0056] The prepared CeO 2 @S v -NiCo-S x OH yThe cyclic stability test results of the / CC flexible composite electrode material used as the positive electrode material of a supercapacitor show a capacity retention rate of 86.5% after 10,000 cycles, demonstrating good cycling performance.

[0057] Example 5

[0058] A kind of CeO 2 Induced composite rich-vacancy S v -NiCo-S x OH y Preparation method of a layered flexible electrode material, comprising the following steps:

[0059] Step 1: Weigh 1.5 mmol Co(NO 3 ) 2 ·6H 2 O and 12 mmol 2-methylimidazole are respectively dissolved in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized aqueous solution with the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60 °C to obtain a ZIF-L nanorod array composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain a layered electrode NiCo-LDH / CC;

[0060] Step 2: Weigh 150 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120 °C for 6 h. After the reaction kettle cools to room temperature, take out the sample, wash the sample several times with deionized water and absolute ethanol, and dry at 60 °C to obtain an S-NiCo-LDH / CC flexible electrode;

[0061] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3 and mix them with the S-NiCo-LDH / CC electrode, react in an autoclave at 180 °C for 6 h. Wash the obtained substance with deionized water and dry to obtain CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0062] The prepared CeO 2 @S v -NiCo-Sx OH y The test results of the cyclic stability of the / CC flexible composite electrode material used as the positive electrode material of the supercapacitor show that after 10,000 cycles, the capacity retention rate is 79.8%, indicating good cycling performance.

[0063] Example 5

[0064] A kind of CeO 2 Induced composite rich-vacancy S v -NiCo-S x OH y Preparation method of the layered flexible electrode material, comprising the following steps:

[0065] Step 1, Weigh 1.5 mmol Co(NO 3 ) 2 ·6H 2 O and 12 mmol 2-methylimidazole are respectively dissolved in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized water solution and the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60°C to obtain the ZIF-L nanorod array composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain the layered electrode NiCo-LDH / CC;

[0066] Step 2, Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120°C for 6 h. After the reaction kettle cools to room temperature, take out the sample, wash the sample several times with deionized water and absolute ethanol, and dry at 60°C to obtain the S-NiCo-LDH / CC flexible electrode;

[0067] Step 3, Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:2, and then mix with the S-NiCo-LDH / CC electrode and react in an autoclave at 180°C for 6 h. Wash the obtained substance with deionized water and dry to obtain CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0068] The prepared CeO 2 @Sv -NiCo-S x OH y The cyclic stability test results of the CeO@S-NiCo-SOH / CC flexible composite electrode material used as the positive electrode material of a supercapacitor show a capacity retention rate of 86.5% after 10,000 cycles, demonstrating good cycling performance.

[0069] Example 6

[0070] A CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y Preparation method of a layered flexible electrode material, comprising the following steps:

[0071] Step 1, Weigh 1.5 mmol Co(NO 3 ) 2 ·6H 2 O and 12 mmol 2-methylimidazole, dissolve them separately in 30 mL of deionized water, mix the Co(NO 3 ) 2 deionized water solution and the 2-methylimidazole solution, stir for 5 minutes, place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60 °C to obtain a ZIF-L nanorod array composite on CC; Weigh 20 mg Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain a layered electrode NiCo-LDH / CC;

[0072] Step 2, Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol, immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120 °C for 6 h, take out the sample after the reaction kettle cools to room temperature, wash the sample several times with deionized water and absolute ethanol, and dry at 60 °C to obtain an S-NiCo-LDH / CC flexible electrode;

[0073] Step 3, Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:4, mix it with the S-NiCo-LDH / CC electrode, react in an autoclave at 180 °C for 6 h, wash the obtained substance with deionized water, and dry to obtain a CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0074] The prepared CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material was used as the positive electrode material of a supercapacitor for cyclic stability testing. After 10,000 cycles, it had a capacity retention rate of 82.3%, showing good cycling performance.

[0075] Example 7

[0076] A method for preparing a CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material, comprising the following steps:

[0077] Step 1: Weigh 1.5 mmol of Co(NO 3 ) 2 ·6H 2 O and 12 mmol of 2-methylimidazole, and dissolve them separately in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized water solution with the 2-methylimidazole solution, stir for 5 minutes, place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60 °C to obtain a ZIF-L nanorod array composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain the layered electrode NiCo-LDH / CC;

[0078] Step 2: Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120 °C for 6 h, take out the sample after the reaction kettle cools to room temperature, wash the sample several times with deionized water and absolute ethanol, and dry at 60 °C to obtain the S-NiCo-LDH / CC flexible electrode;

[0079] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3, mix it with the S-NiCo-LDH / CC electrode, react in an autoclave at 160 °C for 6 h, wash the obtained substance with deionized water, and dry to obtain the CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0080] The prepared CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material was used as the positive electrode material of a supercapacitor for cyclic stability testing. After 10,000 cycles, it had a capacity retention rate of 89.3%, showing good cycling performance.

[0081] Example 8

[0082] A method for preparing a CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material, comprising the following steps:

[0083] Step 1: Weigh 1.5 mmol of Co(NO 3 ) 2 ·6H 2 O and 12 mmol of 2-methylimidazole, and dissolve them separately in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized water solution with the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60 °C to obtain a ZIF-L nanoarray composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 and dissolve it in 10 mL of deionized water. Carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain a layered electrode NiCo-LDH / CC;

[0084] Step 2: Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution and react at 120 °C for 6 h. After the reaction kettle cools to room temperature, take out the sample, wash the sample several times with deionized water and absolute ethanol, and dry at 60 °C to obtain an S-NiCo-LDH / CC flexible electrode;

[0085] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3, then mix with the S-NiCo-LDH / CC electrode and react in an autoclave at 200 °C for 6 h. Wash the obtained substance with deionized water and dry to obtain CeO 2 @S v -NiCo-S x OHy CeO@S-NiCo-SOH / CC flexible composite electrode material.

[0086] The prepared CeO 2 @S v -NiCo-S x OH y When the CeO@S-NiCo-SOH / CC flexible composite electrode material is used as the positive electrode material of a supercapacitor for cyclic stability testing, after 10,000 cycles, it has a capacity retention rate of 81.5%, showing good cyclic performance.

[0087] Example 9

[0088] A preparation method of a CeO-induced composite rich-vacancy S-NiCo-SOH layered flexible electrode material, comprising the following steps: 2 induced composite rich-vacancy S v -NiCo-S x OH y Step 1: Weigh 1.5 mmol of Co(NO

[0089] ) 3 ·6H 2 O and 12 mmol of 2-methylimidazole, dissolve them separately in 30 mL of deionized water, mix the Co(NO 2 ) 3 ) 2 deionized water solution with the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60°C to obtain a ZIF-L nanoarray composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain a layered electrode NiCo-LDH / CC;

[0090] Step 2: Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120°C for 6 h. After the reaction kettle cools to room temperature, take out the sample, wash the sample several times with deionized water and absolute ethanol, and dry at 60°C to obtain an S-NiCo-LDH / CC flexible electrode;

[0091] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3, mix them with the S-NiCo-LDH / CC electrode, react in an autoclave at 180°C for 4 h, wash the obtained substance with deionized water, and dry to obtain CeO 2 @S v-NiCo-S x OH y / CC flexible composite electrode material.

[0092] The prepared CeO 2 @S v -NiCo-S x OH y / CC flexible composite electrode material was used as the positive electrode material of a supercapacitor for cyclic stability testing. After 10,000 cycles, it had a capacity retention rate of 86.8%, showing good cyclic performance.

[0093] Example 10

[0094] A preparation method of a CeO 2 induced composite rich-vacancy S v -NiCo-S x OH y layered flexible electrode material, comprising the following steps:

[0095] Step 1: Weigh 1.5 mmol of Co(NO 3 ) 2 ·6H 2 O and 12 mmol of 2-methylimidazole and dissolve them separately in 30 mL of deionized water. Mix the Co(NO 3 ) 2 deionized aqueous solution with the 2-methylimidazole solution and stir for 5 minutes. Place the carbon cloth CC (1×1 cm 2 ) in the mixed solution, carry out an in-situ self-deposition reaction at room temperature for 10 hours, then centrifuge, and dry at 60°C to obtain a ZIF-L nanorod array composite on CC; Weigh 20 mg of Ni(NO 3 ) 2 dissolve it in 10 mL of deionized water, carry out Lewis acid ion exchange and etching at room temperature for 4 h, wash and dry to obtain the layered electrode NiCo-LDH / CC;

[0096] Step 2: Weigh 100 mg of TAA and dissolve it in 25 mL of ethanol. Immerse the prepared NiCo-LDH / CC electrode in the above solution, react at 120°C for 6 h, take out the sample after the reaction kettle cools to room temperature, wash the sample several times with deionized water and absolute ethanol, and dry at 60°C to obtain the S-NiCo-LDH / CC flexible electrode;

[0097] Step 3: Mix Ce(NO 3 ) 3 and HMT in a molar ratio of 1:3, then mix them with the S-NiCo-LDH / CC electrode and react in an autoclave at 180°C for 8 h. Wash the obtained substance with deionized water and dry to obtain CeO2 @S v -NiCo-S x OH y / CC flexible composite electrode material.

[0098] The prepared CeO 2 @S v -NiCo-S x OH y The / CC flexible composite electrode material is used as the positive electrode material of a supercapacitor for cyclic stability test. After 10,000 cycles, it has a capacity retention rate of 80.5%, showing good cycling performance.

[0099] The above are only embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the description of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A CeO2-induced composite vacancy-rich S v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized in that: The following steps are involved: A. Immerse ZIF-L / CC in a Lewis acid Ni ion aqueous solution for in-situ self-deposition reaction for 1 to 12 hours, wash and dry to obtain a layered electrode NiCo-LDH / CC, wherein the material ratio of the ZIF-L array composited on the carbon cloth CC to the Lewis acid Ni ion aqueous solution is 1 to 3 mg: 5 to 15 mL, preferably 1.5 mg: 10 mL; B. Immerse the layered electrode NiCo-LDH / CC in an ethanol solution containing a sulfur source, move it into a reactor and react at 100-140°C for 4-8h, take it out after the reactor is naturally cooled to room temperature, wash it with deionized water and anhydrous ethanol several times, and dry it at 60°C to obtain a sulfur-coated layered electrode S-NiCo-LDH / CC, wherein the material ratio of NiCo-LDH, sulfur source, and ethanol in the layered electrode is 1-3mg:50-150mg:10-40mL, preferably 1.5mg:100mg:25mL; C. The sulfur-coated layered electrode S-NiCo-LDH / CC, cerium salt and hexamethylenetetramine HMT were mixed and reacted in an autoclave at 160-200 °C for 4-8 h. The obtained product was washed with deionized water and dried to obtain CeO2@S v -NiCo-S x OH y / CC, wherein the material ratio of S-NiCo-LDH, cerium salt and HMT in the layered electrode is 1-3 mg: 0.01-0.10 mol: 0.1-0.3 mol, preferably 1.5 mg: 0.05 mol: 0.15 mol.

2. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step A, ZIF-L / CC is immersed in a Lewis acid Ni ion aqueous solution for in-situ self-deposition reaction for 4 hours, and then washed and dried to obtain a layered electrode NiCo-LDH / CC.

3. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step A, the ZIF-L / CC is prepared by mixing equal volumes of cobalt salt-deionized water solution and 2-methylimidazole-deionized water solution and stirring evenly. 2 ) is placed in a mixed solution and allowed to stand for 10 h, then washed and dried at 60°C to obtain the obtained solution, wherein the cobalt salt-deionized water solution is a mixture of cobalt salt and deionized water at a ratio of 1-3 mmol:15-45 mL, preferably 1.5 mmol:30 mL, and the cobalt salt is Co(NO3)2 or CoCl2, preferably Co(NO3)2; the 2-methylimidazole-deionized water solution is a mixture of 2-methylimidazole and deionized water at a ratio of 10-15 mmol:15-45 mL, preferably 12 mmol:30 mL.

4. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step A, the Lewis acid Ni ion aqueous solution is prepared by dissolving nickel salt in deionized water in a ratio of 10-30 mg:5-15 mL, preferably 20 mg:10 mL, wherein the nickel salt is Ni(NO3)2 or NiCl2, preferably Ni(NO3)2.

5. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step B, the layered electrode NiCo-LDH / CC is immersed in an ethanol solution containing a sulfur source and moved into a reactor to react at 120° C. for 6 hours.

6. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step B, the ethanol solution containing the sulfur source is prepared according to the ratio of sulfur source to ethanol at 50-150 mg:10-40 mL, preferably 100 mg:25 mL, wherein the sulfur source is thioacetamide TAA or sodium sulfide Na2S, preferably TAA.

7. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step C, the sulfur-coated layered electrode S-NiCo-LDH / CC, cerium salt and hexamethylenetetramine HMT were mixed and reacted in an autoclave at 180 °C for 6 h. The obtained product was washed with deionized water and dried to obtain CeO2@S v -NiCo-S x OH y / CC.

8. The CeO2-induced composite vacancy-rich S according to claim 1 v -NiCo-S x OH y The method for preparing a layered flexible electrode material is characterized by: In step C, the cerium salt is Ce(NO3)3 or CeCl3, preferably Ce(NO3)3.

9. CeO2-induced composite vacancy-rich S prepared by the method according to any one of claims 1 to 8 v -NiCo-S x OH y Layered flexible electrode materials.

10. A CeO2-induced composite vacancy-rich S as claimed in claim 9 v -NiCo-S x OH y Application of layered flexible electrode materials, characterized by: It is applied to the positive electrode of supercapacitors.

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