A high specific energy-rate cobalt-based metal organic framework negative electrode material, a preparation method and application thereof

Abstract

The application belongs to the technical field of new material preparation of lithium ion battery negative electrode, and particularly relates to a high specific energy-ratio cobalt-based metal organic framework negative electrode material, a preparation method and application, and particularly comprises the following steps: S1: triphenylamine triamide derived hexacarboxylic acid organic ligand (H6NTTA, C 45 H 30 N4O 15 ) and cobalt nitrate hexahydrate (Co(NO3)2·6H2O), N,N-diethylformamide (DMF) and ethanol are mixed and added into a reaction kettle, the reaction kettle is sealed and placed in a constant temperature oven to react, after the reaction is completed, the reaction kettle is cooled to room temperature to obtain a cobalt-based metal organic framework material (Co-NTTA MOFs); S2: the Co-NTTA MOFs obtained in S1 is mixed with conductive carbon black, a binder and a solvent to obtain a mixture, the mixture is stirred after being degassed to obtain a uniform slurry, the slurry is dried at a constant temperature under vacuum, and the cobalt-based metal organic framework negative electrode is obtained after being cut. The preparation method has a simple preparation process and simple process, and is conducive to directly forming a high-efficiency production process production line.

Description

Technical Field

[0001] This invention belongs to the field of new lithium-ion battery anode material preparation technology, specifically involving a high specific energy-rate type cobalt-based metal-organic framework anode material, its preparation method and application. Background Technology

[0002] With the rapid development of portable electronic devices, electric vehicles, aviation equipment, and smart grids, traditional chemical power sources, represented by lithium-ion batteries, are struggling to meet the urgent needs of national strategies and consumers for long battery life and fast charging. Therefore, there is a pressing need to develop high-energy-density, high-rate energy storage technologies that surpass traditional electrochemical energy sources. Graphite, as the most mature anode material currently used in lithium-ion batteries, possesses advantages such as structural stability, low lithium intercalation potential, long cycle life, high conductivity, and low cost. However, the theoretical specific capacity of graphite anodes is low (372 mAh g / g). -1 Furthermore, in practical applications, inorganic anode materials face challenges such as the continuous growth of the surface solid electrolyte interphase (SEI) film and the difficulty in achieving fast charging. In recent years, transition metal oxides, sulfides, nitrides, and silicon, germanium, and tin alloys have gradually become ideal candidates to replace graphite, attracting widespread attention from the scientific research community and the battery industry, and have achieved initial applications. However, during the lithiation / delithiation process, these inorganic anode materials often experience severe volume effects, leading to mechanical pulverization of the battery material, and the SEI film on the electrode surface grows dynamically, ultimately resulting in rapid capacity decay and shortened cycle life, thus restricting their practical application. In addition to performance bottlenecks, issues such as resource reserves, synthesis energy consumption, and the ease of battery recycling also urgently require key attention when developing inorganic anode materials.

[0003] Organic materials have attracted significant attention as electrode materials in recent years due to their advantages such as being environmentally friendly, having highly designable molecular structures, and tunable redox potentials. However, organic electrode materials are prone to dissolution and shuttling, and have strong electrical insulation properties, which severely limit their potential to simultaneously achieve high reversible capacity and excellent rate performance. Therefore, exploring anode materials with stable structures and superior electrochemical performance has become an important research direction for the development of next-generation lithium-ion batteries. Metal-organic frameworks (MOFs) are a class of crystalline porous materials formed by the self-assembly of organic ligands and inorganic metal ions or metal clusters through coordination bonds. Due to their advantages such as high specific surface area, abundant pore structure, and easy functionalization, they have been widely used in gas storage and separation, heterogeneous catalysis, sensing, drug delivery, and nonlinear optics. In recent years, MOF materials have also shown great application potential in the field of electrochemical energy storage and have been proven to be directly used as anode materials for lithium-ion batteries. It achieves efficient lithium storage through the functional groups on organic ligands and multiple active sites in the metal center, and its excellent structural stability effectively solves the dissolution shuttle problem of organic electrode materials, thus achieving high capacity output and long cycle stability. However, the rate performance of current metal-organic frameworks as lithium-ion battery anode materials still needs further improvement to meet the requirements of fast charge and discharge. Therefore, it is urgent to design and develop sp... 2 Metal-organic framework (MOF) anode materials with hybrid carbon structures. By enhancing electron delocalization, reducing the band gap, and improving electronic conductivity, more efficient, faster, and more stable lithium storage behavior can be achieved. Summary of the Invention

[0004] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention aims to provide a high specific energy-rate type cobalt-based metal-organic framework anode material, its preparation method, and its application. The preparation method includes the following steps:

[0005] S1: The triphenylamine triamide-derived hexacarboxylic acid organic ligand, Co(NO3)2·6H2O, N,N-diethylformamide and ethanol were mixed and added to the reaction vessel. After sealing, the mixture was placed in a constant temperature oven for reaction. After the reaction was completed, the mixture was cooled to room temperature to obtain Co-NTTA MOFs.

[0006] S2: The Co-NTTA MOFs obtained in S1 are mixed with conductive carbon black, binder and solvent to obtain a mixture. After degassing and stirring, a uniform slurry is obtained. The slurry is dried under vacuum at a constant temperature and then cut to obtain a cobalt-based metal-organic framework anode.

[0007] Furthermore, the reaction time described in S1 is 3 days, and the reaction vessel is 25 mL.

[0008] Furthermore, the volume ratio of N,N-diethylformamide to ethanol in S1 is 2-6:1-3.

[0009] A high specific energy-rate cobalt-based metal-organic framework anode material, wherein the anode material has abundant lithium storage sites, excellent structural stability, π-aromatic conjugated network, and π...π stacked sp 2 Hybridized carbon structure.

[0010] Application of a high specific energy-rate type cobalt-based metal-organic framework anode material, wherein the cobalt-based metal-organic framework anode material is used in assembling lithium-ion batteries and hybrid ion capacitors.

[0011] Beneficial effects

[0012] (1) The method for preparing a high specific energy-rate type cobalt-based metal-organic framework anode material provided by the present invention uses triphenylamine triamide-derived hexacarboxylic acid (H6NTTA) as an organic ligand and cobalt nitrate hexahydrate (Co(NO3)2·6H2O) as a metal center source to prepare a three-dimensional cobalt-based metal-organic framework (Co-NTTA MOFs) material through a solvothermal reaction. The preparation process is simple, the process is easy, the experiment is reproducible, and it is conducive to directly forming a high-efficiency production line.

[0013] (2) Through the high specific energy-rate type cobalt-based metal-organic framework anode material provided by the present invention, the novel Co-NTTA MOFs prepared by the present invention have abundant lithium storage sites (-OC=O, -NH-C=O, active -C=C functional groups and cobalt cations), excellent structural stability, π-aromatic conjugated network and π...π stacked sp 2 Hybridized carbon.

[0014] (3) Through the application of a high specific energy-rate type cobalt-based metal-organic framework anode material provided by the present invention, this invention directly uses Co-NTTAMOFs with a novel structure as anode materials for lithium-ion batteries. The assembled Co-NTTAMOF||Li lithium-ion battery achieves a current density of 200 mAg. -1 At that time, the capacity output reached up to 956mAhg -1 ; and in 5Ag -1 At high current density, after 600 cycles, the discharge capacity remains at 483 mAh g. -1 It exhibits excellent electrochemical stability and rate performance. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0016] Figure 1 This is a schematic diagram of the synthesis process of the high specific energy-rate type cobalt-based metal-organic framework anode material prepared in Example 1 of the present invention;

[0017] Figure 2 The image shows the attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrum of the high specific energy-rate type cobalt-based metal-organic framework anode material prepared in Example 1 of this invention.

[0018] Figure 3 The powder X-ray diffraction (PXRD) pattern of the high specific energy-rate type cobalt-based metal-organic framework anode material prepared in Example 1 of this invention;

[0019] Figure 4 The images shown are scanning electron microscope images and morphological schematic diagrams of the high specific energy-rate type cobalt-based metal-organic framework anode material prepared in Example 1 of this invention.

[0020] Figure 5 HAADF-STEM image, selected area electron diffraction image and corresponding elemental distribution image of the high specific energy-rate type cobalt-based metal-organic framework anode material prepared in Example 1 of the present invention;

[0021] Figure 6 The rate performance diagram shows the high specific energy-rate type cobalt-based metal-organic framework anode assembly Co-NTTAMOF||Li lithium-ion battery prepared in Example 1 of this invention.

[0022] Figure 7 This is a comparison chart of the rate performance of the high specific energy-rate type cobalt-based metal-organic framework anode prepared in Example 1 of the present invention with that of organic framework-based anode materials reported in the literature for use in advanced lithium-ion batteries.

[0023] Figure 8 The electrochemical impedance spectroscopy of the high specific energy-rate type cobalt-based metal-organic framework anode prepared in Example 1 of this invention for different cycle periods is shown.

[0024] Figure 9 The high specific energy-rate type cobalt-based metal-organic framework anode assembly of Co-NTTAMOF||Li lithium-ion batteries prepared in Example 1 of this invention was used in 1 and 5Ag... -1 Long-cycle curves and coulomb efficiency plots at current density;

[0025] Figure 10 The high specific energy-rate type cobalt-based metal-organic framework anode assembly of Co-NTTAMOF||Li lithium-ion batteries prepared in Example 1 of this invention was used in 1 and 5Ag... -1 Charge-discharge curves at different current densities with different numbers of cycles;

[0026] Figure 11 This is a comparison chart of the long-cycle performance of the high specific energy-rate type cobalt-based metal-organic framework anode prepared in Example 1 of the present invention with that of organic framework-based anode materials reported in the literature for use in advanced lithium-ion batteries.

[0027] Figure 12 The rate performance diagram shows the Co-NTTA MOF||AC lithium-ion hybrid capacitors constructed with different mass ratios of high specific energy and rate type cobalt-based metal-organic framework negative electrode and activated carbon positive electrode prepared in Example 1 of this invention.

[0028] Figure 13 This is a comparison of the electrochemical performance of the high specific energy-rate type cobalt-based metal-organic framework anode prepared in Example 1 of the present invention with that of organic framework-based anode materials reported in the literature for use in advanced Co-NTTA MOF||AC lithium-ion hybrid capacitors.

[0029] Figure 14 The Co-NTTA MOF||AC lithium-ion hybrid capacitor constructed from the high specific energy-rate type cobalt-based metal-organic framework anode and activated carbon cathode prepared in Example 1 of this invention was tested at 5Ag. -1 Long-cycle curves at current density and charge-discharge curves with different numbers of cycles. Detailed Implementation

[0030] The following will describe in conjunction with embodiments 1 to 6 of the present invention and the appendix. Figures 1-14 The technical solutions of the present invention have been clearly and completely described. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] The preparation method provided by this invention offers a sp(s) structure that possesses abundant lithium storage sites (-OC=O, -NH-C=O, active -C=C functional groups and cobalt cations), excellent structural stability, a π-aromatic conjugated network, and π...π stacking. 2 Novel Co-NTTA MOFs of hybrid carbon. This material is produced by deriving hexacarboxylic acid (H6NTTA, C...) from triphenylamine triamide. 45 H 30 N4O 15Using cobalt nitrate hexahydrate (Co(NO3)2·6H2O) as the metal center source, three-dimensional cobalt-based metal-organic frameworks (Co-NTTA MOFs, Co7C) were prepared via a solvothermal reaction through coordinative bond-bridged self-assembly. 90 N8O 62.50 H 111 Using Co-NTTAMOFs directly as the anode material for lithium-ion batteries, the assembled Co-NTTAMOF||Li lithium-ion battery exhibited a high specific capacity (956 mAh g⁻¹). -1 200mAg -1 ) and excellent rate performance (483mAh g) -1 600 th 5Ag -1 Based on the Faraday redox reaction of Co-NTTA MOFs and the fast intercalation pseudocapacitive lithium storage mechanism, a 4.3V high-performance lithium-ion hybrid capacitor was successfully constructed.

[0032] This invention provides a method for preparing a high specific energy-rate type cobalt-based metal-organic framework anode material, comprising the following steps:

[0033] S1: First, triphenylamine triamide-derived hexacarboxylic acid organic ligand, metal salt Co(NO3)2·6H2O, N,N-diethylformamide (DMF), and ethanol were added to a reaction vessel, sealed, and placed in a constant temperature oven for three days. After the reaction, the mixture was cooled to room temperature to obtain light purple cubic crystal Co-NTTA MOFs. S2: The light purple powdered Co-NTTA MOFs obtained in S1, conductive carbon black, and binder were mixed evenly in a certain mass ratio, a solvent was added, and the mixture was stirred using a THINKY degassing machine to form a slurry. The resulting black viscous slurry was evenly coated onto one side of a copper foil current collector and dried under vacuum at a constant temperature. Circular electrode sheets with a diameter of 11 mm were cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 1.5–2.0 mg / cm³. -2 Cobalt-based metal-organic framework (Co-NTTA MOF) anodes were obtained.

[0034] Example 1

[0035] S1: Derivatize triphenylamine triamide into hexacarboxylic acid (C 45 H 30 N4O 15Organic ligands (17 mg, 0.02 mmol), metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 4 mL) and ethanol (2 mL) were added to a 25 mL reaction vessel, sealed, and placed in a 100 °C constant temperature oven for three days. After the reaction was completed, the mixture was cooled to room temperature to finally obtain light purple cubic crystals Co-NTTA MOFs.

[0036] The Co-NTTA MOFs obtained from S1 were mixed with super P and PVDF at a mass ratio of 6:3:1, and N-methylpyrrolidone (NMP) solvent was added. The mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black viscous slurry was evenly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 1.5 mg / cm³. -2 A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium hexafluorophosphate-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTA MOF electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0037] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%. Subsequently, the battery was discharged to 0.01V (vs. Li / Li). + Then, the full battery was assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 9:0.5:0.5, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was evenly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:7. The total mass of Co-NTTA MOFs and activated carbon was controlled to be within 16 mg / cm³. -2 .

[0038] Combination Figure 1The synthetic route and molecular structure diagram of Co-NTTA MOFs are shown. In this method, H6NTTA organic ligand and Co(NO3)2·6H2O are uniformly dispersed in a mixed solvent containing N,N-diethylformamide and ethanol. A simple wet chemical reaction is used to promote uniform crystallization and generate a light purple powder, which is the Co-NTTA MOF product.

[0039] Combination Figure 2 The chemical structure of Co-NTTA MOFs was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), which confirmed that coordination polymerization was successfully achieved between the H6NTTA organic ligand and the cobalt cation.

[0040] Combination Figure 3 It can be seen that the powder X-ray diffraction (PXRD) pattern of Co-NTTA MOFs is highly consistent with the simulated pattern of single crystal data, confirming its phase purity and high crystallinity.

[0041] Combination Figure 4 It can be seen that Co-NTTA MOFs have regular shapes and large crystal sizes, exhibiting a smooth, standard cubic shape with an average side length of 20–30 μm.

[0042] Combination Figure 5 The energy-dispersive X-ray (EDS) elemental distribution images confirm that Co, C, O, and N elements are uniformly distributed in Co-NTTAMOFs.

[0043] Combination Figure 6 It can be seen that Co-NTTA||Li lithium-ion batteries have a range of 0.2–10 Ag. -1 It exhibits excellent rate performance at current densities.

[0044] Combination Figure 7 It can be seen that the rate performance of Co-NTTA||Li lithium-ion batteries far exceeds the rate characteristics of almost all previously reported organic framework-based anode materials, indicating that Co-NTTAMOFs anode materials exhibit ultrafast lithium storage kinetics.

[0045] Combination Figure 8 The Nyquist plots of Co-NTTA||Li lithium-ion batteries at different cycle numbers show excellent interfacial stability and fast electrochemical response.

[0046] Combination Figure 9 It can be seen that Co-NTTA||Li lithium-ion batteries have performance at 1 and 5Ag. -1 It exhibits excellent long-cycle stability at current density and has high coulombic efficiency.

[0047] Combination Figure 10It can be seen that Co-NTTA||Li lithium-ion batteries at 1Ag -1 The charge-discharge curves at current density are highly overlapping, indicating its high reversibility and coulombic efficiency exceeding 99.8%.

[0048] Combination Figure 11 It is evident that the long-cycle performance of Co-NTTA||Li lithium-ion batteries is particularly outstanding among the long-cycle characteristics of a series of organic framework-based anode materials reported to date, further emphasizing their potential in practical applications.

[0049] Combination Figure 12 It can be seen that the optimal mass ratio of Co-NTTA negative electrode to AC positive electrode in Co-NTTA||AC lithium-ion hybrid capacitor is 1:7, and it exhibits excellent rate performance.

[0050] Combination Figure 13 It can be seen that the energy density and power density of the Co-NTTA||AC lithium-ion hybrid capacitor are significantly superior to the electrochemical performance of the recently reported advanced organic framework-based lithium-ion hybrid capacitor.

[0051] Combination Figure 14 It can be seen that the Co-NTTA||AC lithium-ion hybrid capacitor is at 5Ag -1 After 10,000 cycles at current density, the average capacity decay rate per cycle is as low as 0.00024%, demonstrating an extremely long service life.

[0052] Example 2

[0053] S1: Triphenylamine triamide-derived hexacarboxylic acid (17 mg, 0.02 mmol) organic ligand, metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 2 mL) and ethanol (2 mL) were added to a 25 mL reaction vessel, sealed and placed in a 100 °C constant temperature oven for three days. After the reaction was completed, the mixture was cooled to room temperature to finally obtain light purple cubic crystals Co-NTTA MOFs.

[0054] The Co-NTTA MOFs, KB, and PTFE obtained from S1 were mixed evenly at a mass ratio of 5:4:1. Deionized water / ethanol solvent was added, and the mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black viscous slurry was evenly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were then cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 2.0 mg / cm³. -2A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference electrode and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium bis(trifluoromethanesulfonyl)imide-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTAMOFs electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0055] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%; subsequently, the battery was discharged to 0.01V (vs. Li / Li). + Then, the full battery was assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 8:1:1, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was uniformly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:4. The total mass of Co-NTTA MOFs and activated carbon was controlled to be within 13 mg / cm³. -2 .

[0056] Example 3

[0057] S1: Triphenylamine triamide-derived hexacarboxylic acid (17 mg, 0.02 mmol) organic ligand, metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 6 mL) and ethanol (1 mL) were added to a 25 mL reaction vessel, sealed, and placed in a 100 °C constant temperature oven for three days. After the reaction was completed, the mixture was cooled to room temperature to obtain light purple cubic crystals Co-NTTA MOFs.

[0058] The Co-NTTA MOFs, carbon nanotubes, and acrylonitrile copolymer dispersions obtained in S1 were mixed uniformly at a mass ratio of 8:1:1. Deionized water solvent was added, and the mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black viscous slurry was uniformly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 2.0 mg / cm³. -2A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference electrode and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium perchlorate-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTA MOF electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0059] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%. Subsequently, the battery was discharged to 0.01V (vs. Li / Li). + Then, the full battery was assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 7:2:1, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was uniformly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:12. The total mass of Co-NTTA MOFs and activated carbon was controlled within 15 mg / cm³. -2 .

[0060] Example 4

[0061] S1: Triphenylamine triamide-derived hexacarboxylic acid (17 mg, 0.02 mmol) organic ligand, metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 2 mL) and ethanol (1 mL) were added to a 25 mL reaction vessel, sealed and placed in a 100 °C constant temperature oven for three days. After the reaction was completed, the mixture was cooled to room temperature to finally obtain light purple cubic crystals Co-NTTA MOFs.

[0062] The Co-NTTA MOFs, carbon nanotubes, and acrylonitrile copolymer dispersions obtained in S1 were mixed uniformly at a mass ratio of 8:1:1. Solvent was added, and the mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black, viscous slurry was uniformly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were then cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 1.9 mg / cm³. -2A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference electrode and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium perchlorate-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTA MOF electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0063] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%. Subsequently, the battery was discharged to 0.01V (vs. Li / Li). + Then, the full battery was assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 7:2:1, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was uniformly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:12. The total mass of Co-NTTA MOFs and activated carbon was controlled to be within 14 mg / cm³. -2

[0064] Example 5

[0065] S1: Triphenylamine triamide-derived hexacarboxylic acid (17 mg, 0.02 mmol) organic ligand, metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 6 mL) and ethanol (3 mL) were added to a 25 mL reaction vessel, sealed and placed in a 100 °C constant temperature oven for three days. After the reaction was completed, the mixture was cooled to room temperature to finally obtain light purple cubic crystals Co-NTTA MOFs.

[0066] The Co-NTTA MOFs, carbon nanotubes, and acrylonitrile copolymer dispersions obtained in S1 were mixed evenly at a mass ratio of 8:1:1. Deionized water solvent was added, and the mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black viscous slurry was evenly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 1.6 mg / cm³. -2A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference electrode and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium perchlorate-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTA MOF electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0067] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%. Subsequently, the battery was discharged to 0.01V (vs. Li / Li). + Then, the full battery was assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 7:2:1, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was uniformly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:12. The total mass of Co-NTTA MOFs and activated carbon was controlled to be within 13 mg / cm³. -2 .

[0068] Example 6

[0069] S1; Triphenylamine triamide-derived hexacarboxylic acid (17 mg, 0.02 mmol) organic ligand, metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 3 mL) and ethanol (2 mL) were added to a 25 mL reaction vessel, sealed and placed in a 100 °C constant temperature oven for three days; after the reaction was completed, it was cooled to room temperature to finally obtain light purple cubic blocky crystals Co-NTTA MOFs.

[0070] The Co-NTTA MOFs, carbon nanotubes, and acrylonitrile copolymer dispersions obtained in S1 were mixed evenly at a mass ratio of 5:4:1. Deionized water solvent was added, and the mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black viscous slurry was evenly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 1.5 mg / cm³. -2A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference electrode and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium perchlorate-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTA MOF electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0071] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%. Subsequently, the battery was discharged to 0.01V (vs. Li / Li). + Then, the full battery was assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 7:2:1, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was uniformly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:12. The total mass of Co-NTTA MOFs and activated carbon was controlled within 15 mg / cm³. -2 .

[0072] Example 7

[0073] S1: Triphenylamine triamide-derived hexacarboxylic acid (17 mg, 0.02 mmol) organic ligand, metal salt Co(NO3)2·6H2O (29.1 mg, 0.1 mmol), N,N-diethylformamide (DMF, 5 mL) and ethanol (3 mL) were added to a 25 mL reaction vessel, sealed and placed in a 100 °C constant temperature oven for three days. After the reaction was completed, the mixture was cooled to room temperature to finally obtain light purple cubic crystals Co-NTTA MOFs.

[0074] The Co-NTTA MOFs, carbon nanotubes, and acrylonitrile copolymer dispersions obtained in S1 were mixed uniformly at a mass ratio of 5:4:1. Deionized water solvent was added, and the mixture was stirred for 30 minutes using a THINKY degassing machine to prepare a slurry. The resulting black viscous slurry was uniformly coated onto one side of a copper foil current collector and dried at 120°C under vacuum for 12 hours. Circular electrode sheets with a diameter of 11 mm were cut using a cutting machine. The active mass of a single lithium-ion battery negative electrode sheet was 1.7 mg / cm³. -2A cobalt-based metal-organic framework (MOF) anode was obtained. Using a lithium sheet as the reference electrode and counter electrode, a Celgard 2400 membrane as the separator, and a 1M lithium perchlorate-ethylene carbonate / diethyl carbonate (1:1, volume ratio) electrolyte, the prepared Co-NTTA MOF electrode sheet was used as the anode to assemble a Co-NTTA MOF||Li lithium-ion battery.

[0075] To reduce polarization and improve coulombic efficiency, Co-NTTA MOFs anodes are used in lithium-ion batteries at 50 mAg. -1 Pre-cycling was performed at current density until the coulombic efficiency exceeded 95%. Subsequently, the battery was discharged to 0.01V (vs. Li / Li). + The full battery was then assembled. A lithium-ion hybrid capacitor was constructed using pre-lithiated Co-NTTA MOFs as the negative electrode and activated carbon as the positive electrode. Activated carbon, conductive carbon black, and binder were mixed uniformly at a mass ratio of 7:2:1, solvent was added, and the mixture was stirred for 30 minutes in a THINKY degassing machine to form a slurry. The resulting black viscous slurry was uniformly coated onto one side of an aluminum foil current collector and dried at 120°C under vacuum for 12 hours. The optimal electrochemical performance of the lithium-ion hybrid capacitor was achieved by optimizing the active material mass ratio between the Co-NTTA MOFs negative electrode and the activated carbon positive electrode to 1:12. The total mass of Co-NTTA MOFs and activated carbon was controlled to be within 16 mg / cm³. -2 .

[0076] As can be seen from the above embodiments, the high specific energy-rate type cobalt-based metal-organic framework anode material prepared in the embodiments of the present invention benefits from abundant lithium storage sites (-OC=O, -NH-C=O, active -C=C functional groups and cobalt cations), excellent structural stability, π-aromatic conjugated network and π…π stacked sp 2 The hybrid carbon-assembled Co-NTTA MOF||Li lithium-ion battery exhibits a high specific capacity (956 mAh g). -1 200mAg -1 ) and excellent rate performance (483mAh g) -1 600 th 5Ag -1 Based on the Faraday redox reaction and rapid intercalation pseudocapacitive lithium storage behavior of Co-NTTA MOFs, a high-performance 4.3V lithium-ion hybrid capacitor was successfully constructed. This invention provides assurance for the cycle stability and rate performance of the anode material, and also provides new research ideas for the development of advanced organic framework materials for electrochemical energy storage technology.

[0077] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and function as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, without departing from the spirit of this application, various modifications, alterations, substitutions, simplifications, and other modifications that can be conceived by those skilled in the art to the embodiments, as well as other ways of constructing by combining some of the constituent elements of the embodiments, are also included in the protection scope of this invention. The protection scope of this invention is determined by the claims.

Claims

1. A method for preparing a high specific energy-rate type cobalt-based metal-organic framework anode material, characterized in that, Includes the following steps: S1: Triphenylamine triamide-derived hexacarboxylic acid organic ligand and Co(NO3)2·6H2O were mixed at a molar ratio of 1:5, and then mixed with N,N-diethylformamide and ethanol solvent and added to a reaction vessel. After sealing, the mixture was placed in a constant temperature oven for reaction. After the reaction was completed, it was cooled to room temperature to obtain Co-NTTA MOFs. The volume ratio of N,N-diethylformamide to ethanol was 2-6:1-3. The reaction time was 3 days, and the reaction vessel was 25 mL. S2: The Co-NTTA MOFs obtained in S1 are mixed with conductive carbon black and binder in a mass ratio of 6:3:

1. N-methylpyrrolidone solvent is added, and after degassing and stirring, the mixture is coated onto copper foil and vacuum dried to obtain cobalt-based metal-organic framework anode material.

2. A high specific energy-rate type cobalt-based metal-organic framework anode material obtained by the preparation method according to claim 1, characterized in that, The negative electrode material is an sp...p...structured material with abundant lithium storage sites, excellent structural stability, π-aromatic conjugated network, and π...π stacking. 2 Hybridized carbon structure.

3. The application of the high specific energy-rate type cobalt-based metal-organic framework anode material according to claim 2, wherein the cobalt-based metal-organic framework anode material is used in assembling lithium-ion batteries and lithium-ion hybrid capacitors.

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