Imide-based conductive conjugated coordination polymers, methods of making and using the same

Abstract

The application discloses an imide-based conductive conjugated coordination polymer and a preparation method and application thereof, and belongs to the technical field of battery materials. The preparation method of the conductive conjugated coordination polymer comprises the following steps: adding N,N'-dihydroxynaphthalene diimide into a solvent, and then adding a metal salt to mix and heat to obtain the conductive conjugated coordination polymer. In addition, the application further provides a conductive conjugated coordination polymer prepared by the above preparation method. In addition, the application further provides the application of the conductive conjugated coordination polymer prepared by the above preparation method or the above conductive conjugated coordination polymer as a lithium ion battery positive electrode material or a sodium ion battery positive electrode material. The polymer has a high specific capacity as the lithium ion battery positive electrode material or the sodium ion battery positive electrode material.

Description

Technical Field

[0001] This invention relates to the field of battery materials technology, specifically to an imide-based conductive conjugated coordination polymer, its preparation method, and its application. Background Technology

[0002] Lithium-ion and sodium-ion batteries, as two important electrochemical energy storage devices, have been widely used due to their advantages such as high energy density, long cycle life, and environmental friendliness. However, traditional cathode electrode materials suffer from problems such as resource scarcity, high cost, and limited specific capacity, which restrict their further development and application. Organic electrode materials, with their advantages of high theoretical capacity, renewability, and environmental friendliness, are among the key materials for research in lithium / sodium-ion batteries.

[0003] In organic electrode materials, conductive conjugated coordination polymers not only inherit the advantages of high specific surface area and porous structure from traditional coordination polymers, but also possess excellent electron transport performance and abundant redox active sites, effectively improving the specific capacity, rate performance, and cycle stability of electrode materials. In lithium / sodium-ion batteries, conductive conjugated coordination polymers, as cathode materials, can provide high specific capacity and excellent cycle stability. Their porous structure facilitates electrolyte wetting and ion transport, while the conjugated ligands enable efficient electron transport and reduce the internal resistance of the electrode. Therefore, developing a highly efficient and stable conductive conjugated coordination polymer material and exploring its application in lithium-sodium battery cathode materials has significant scientific and practical value.

[0004] Currently, some conductive conjugated coordination polymer materials have been used as cathode materials in lithium / sodium-ion battery research, achieving high specific capacity and excellent cycle stability. However, there is still a need to develop new conductive conjugated coordination polymers with high specific capacity and excellent cycle stability. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide an imide-based conductive conjugated coordination polymer, its preparation method and application, thereby solving the technical problem of how to achieve high specific capacity and excellent cycle stability of battery materials in the prior art.

[0006] To achieve the above-mentioned technical objectives, the present invention provides a method for preparing an imide-based conductive conjugated coordination polymer, comprising the following steps:

[0007] N,N'-dihydroxynaphthalimide was added to a solvent, followed by the addition of a metal salt and heating to obtain an imide-based conductive conjugated coordination polymer.

[0008] In any embodiment, the solvent is DMF.

[0009] In any embodiment, the metal salt is one or more of soluble nickel salt, soluble manganese salt, soluble calcium salt, soluble copper salt, and soluble cobalt salt.

[0010] In any embodiment, the soluble nickel salt comprises nickel nitrate; and / or, the soluble manganese salt comprises manganese chloride; and / or, the soluble calcium salt comprises calcium nitrate; and / or, the soluble copper salt comprises copper nitrate; and / or, the soluble cobalt salt comprises cobalt chloride.

[0011] In any embodiment, the molar ratio of the N,N'-dihydroxynaphthalimide to the metal salt is 1:(1-1.5); and / or, the heating reaction is carried out at a temperature of 100-120°C for a time of 48-72 h.

[0012] In any embodiment, the N,N'-dihydroxynaphthalimide is prepared by the following steps:

[0013] The N,N'-dihydroxynaphthalenediimide was obtained by mixing and heating 1,4,5,8-naphthalenetetracarboxylic anhydride and hydroxylamine hydrochloride in a solvent.

[0014] In any embodiment, the molar ratio of 1,4,5,8-naphthocarboxylic anhydride to hydroxylamine hydrochloride is 1:(2-2.5); and / or, the mixing and heating temperature is 65-70°C, and the time is 5-7 hours.

[0015] In addition, the present invention also proposes an imide-based conductive conjugated coordination polymer, which is prepared by the above preparation method.

[0016] Furthermore, this invention also proposes the application of the imide-based conductive conjugated coordination polymer prepared by the above-mentioned method, or the above-mentioned imide-based conductive conjugated coordination polymer, as a cathode material for lithium-ion batteries or sodium-ion batteries.

[0017] In any embodiment, the conductive conjugated coordination polymer, super P and polyvinylidene fluoride are ground and mixed, then NMP solution is added dropwise and grinding is continued. The resulting slurry is coated onto aluminum foil and vacuum dried to obtain a lithium or sodium ion battery cathode.

[0018] Compared with the prior art, the beneficial effects of the present invention include: the preparation method of the conductive conjugated coordination polymer based on imide proposed in the present invention involves adding N,N'-dihydroxynaphthalimide to a solvent, then adding a metal salt, mixing and heating to obtain the conductive conjugated coordination polymer based on imide. This polymer, as a cathode material for lithium-ion batteries or sodium-ion batteries, has high specific capacity, excellent charge-discharge curves and cycle performance, showing that it has extremely superior electrochemical performance. Attached Figure Description

[0019] Figure 1 The thermogravimetric curves of the N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 1 are shown.

[0020] Figure 2 The infrared absorption spectra of the N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 1 are shown.

[0021] Figure 3 This is a powder X-ray diffraction pattern of the N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer prepared in Example 1.

[0022] Figure 4 This is a cycle capacity diagram of Ni-ONDI, the N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer prepared in Example 1, as the positive electrode of a lithium-ion battery.

[0023] Figure 5 The charging and discharging curves of Ni-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer prepared in Example 1, as the positive electrode of a lithium-ion battery are shown.

[0024] Figure 6 This is a cycle capacity diagram of Ni-ONDI, the N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer prepared in Example 1, as the positive electrode of a sodium-ion battery.

[0025] Figure 7 The charge-discharge curves of Ni-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated nickel coordination polymer prepared in Example 1, as the positive electrode of a sodium-ion battery are shown.

[0026] Figure 8 The thermogravimetric curves of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 2 are shown.

[0027] Figure 9 The infrared absorption spectra of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 2 are shown.

[0028] Figure 10 This is a powder X-ray diffraction pattern of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer prepared in Example 2.

[0029] Figure 11 This is a cycle capacity diagram of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer Mn-ONDI prepared in Example 2 as the positive electrode of a lithium-ion battery.

[0030] Figure 12 The charging and discharging curves of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer Mn-ONDI prepared in Example 2 as the positive electrode of a lithium-ion battery are shown.

[0031] Figure 13 This is a cycle capacity diagram of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer Mn-ONDI prepared in Example 2 as the positive electrode of a sodium-ion battery.

[0032] Figure 14 The above are the charge-discharge curves of the N,N'-dihydroxynaphthalimide conductive conjugated manganese coordination polymer Mn-ONDI prepared in Example 2 as the positive electrode of a sodium-ion battery.

[0033] Figure 15 This is a thermogravimetric curve of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 3.

[0034] Figure 16 The infrared absorption spectra of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 3 are shown.

[0035] Figure 17 This is a powder X-ray diffraction pattern of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer prepared in Example 3.

[0036] Figure 18 This is a toroidal capacity diagram of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer Ca-ONDI prepared in Example 3 as a positive electrode of a lithium-ion battery.

[0037] Figure 19 The charge-discharge curves of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer Ca-ONDI prepared in Example 3 as the positive electrode of a lithium-ion battery are shown.

[0038] Figure 20 This is a cycle capacity diagram of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer Ca-ONDI prepared in Example 3 as the positive electrode of a sodium-ion battery.

[0039] Figure 21 The charge-discharge curves of the N,N'-dihydroxynaphthalimide conductive conjugated calcium coordination polymer Ca-ONDI prepared in Example 3 as the positive electrode of a sodium-ion battery are shown.

[0040] Figure 22 This is a thermogravimetric curve of the N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 4.

[0041] Figure 23 The infrared absorption spectra of the N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 4 are shown.

[0042] Figure 24 This is a powder X-ray diffraction pattern of the N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer prepared in Example 4.

[0043] Figure 25 This is a cycle capacity diagram of Cu-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer prepared in Example 4, as the positive electrode of a lithium-ion battery.

[0044] Figure 26 The charging and discharging curves of Cu-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer prepared in Example 4, as the positive electrode of a lithium-ion battery are shown.

[0045] Figure 27 This is a cycle capacity diagram of Cu-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer prepared in Example 4, as the positive electrode of a sodium-ion battery.

[0046] Figure 28 The charge-discharge curves of Cu-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated copper coordination polymer prepared in Example 4, as the positive electrode of a sodium-ion battery are shown.

[0047] Figure 29 This is a thermogravimetric curve of the N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 5.

[0048] Figure 30 The infrared absorption spectra of the N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer and N,N'-dihydroxynaphthalimide prepared in Example 5 are shown.

[0049] Figure 31 This is a powder X-ray diffraction pattern of the N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer prepared in Example 5.

[0050] Figure 32 This is a cycle capacity diagram of Co-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer prepared in Example 5, as the positive electrode of a lithium-ion battery.

[0051] Figure 33 The charging and discharging curves of Co-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer prepared in Example 5, as the positive electrode of a lithium-ion battery are shown.

[0052] Figure 34 This is a cycle capacity diagram of Co-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer prepared in Example 5, as the positive electrode of a sodium-ion battery.

[0053] Figure 35 The above are the charge-discharge curves of Co-ONDI, an N,N'-dihydroxynaphthalimide conductive conjugated cobalt coordination polymer prepared in Example 5, as the positive electrode of a sodium-ion battery. Detailed Implementation

[0054] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60–120 and 80–110 are listed for a specific parameter, it is understood that ranges of 60–110 and 80–120 are also expected. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1–3, 1–4, 1–5, 2–3, 2–4, and 2–5. In this application, unless otherwise stated, the numerical range "a–b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0055] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0056] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0057] This specific embodiment provides a method for preparing an imide-based conductive conjugated coordination polymer, comprising the following steps:

[0058] N,N'-dihydroxynaphthalimide is added to the solvent DMF (i.e., dimethylformamide), followed by the addition of a metal salt and heating to obtain an imide-based conductive conjugated coordination polymer; the metal salt is one or more of soluble nickel salt, soluble manganese salt, soluble calcium salt, soluble copper salt, and soluble cobalt salt; the molar ratio of N,N'-dihydroxynaphthalimide to the metal salt is 1:(1-1.5); the heating reaction temperature is 100-120℃, and the time is 48-72h.

[0059] In some embodiments, the soluble nickel salt includes nickel nitrate; the soluble manganese salt includes manganese chloride; the soluble calcium salt includes calcium nitrate; the soluble copper salt includes copper nitrate; and the soluble cobalt salt includes cobalt chloride.

[0060] In some embodiments, the N,N'-dihydroxynaphthalimide is prepared by the following steps:

[0061] The N,N'-dihydroxynaphthalenediimide is obtained by mixing and heating 1,4,5,8-naphthalenetetracarboxylic anhydride and hydroxylamine hydrochloride in a solvent; the molar ratio of 1,4,5,8-naphthalenetetracarboxylic anhydride to hydroxylamine hydrochloride is 1:(2-2.5); the mixing and heating temperature is 65-70℃ and the time is 5-7h; the solvent is DMF.

[0062] The reactions involved in the above preparation method are shown below:

[0063]

[0064] Where M represents a metal ion, such as nickel ion, manganese ion, calcium ion, copper ion or cobalt ion.

[0065] This specific embodiment also proposes an imide-based conductive conjugated coordination polymer, which is prepared by the above preparation method.

[0066] This specific embodiment also proposes the application of the imide-based conductive conjugated coordination polymer or the above-mentioned imide-based conductive conjugated coordination polymer as a positive electrode material for lithium-ion batteries or sodium-ion batteries. The imide-based conductive conjugated coordination polymer, super P and polyvinylidene fluoride are ground and mixed, and then NMP solution is added dropwise to continue grinding. The resulting slurry is coated onto aluminum foil and vacuum dried to obtain a positive electrode for lithium-ion batteries or sodium-ion batteries.

[0067] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0068] In this invention, the terms "some embodiments," "this embodiment," and examples are used to describe a subset of all possible embodiments. However, it is understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0069] If the application documents contain similar descriptions such as "first / second", the following explanation shall be added: In the following description, the terms "first / second / third" are used only to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0070] In this embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, object A and / or object B can represent three situations: object A exists alone, object A and object B exist simultaneously, and object B exists alone.

[0071] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0072] Example 1

[0073] This embodiment proposes an imide-based conductive conjugated coordination polymer, which is prepared by the following steps:

[0074] (1) Add 10 mmol of 1,4,5,8-naphthalenetetracarboxylic anhydride and 21 mmol of hydroxylamine hydrochloride to 20 ml of DMF and mix well. Reflux at 65 °C for 8 h. Filter, wash and dry the crude product to obtain N,N'-dihydroxynaphthalenediimide (i.e. H2ONDI).

[0075] (2) Dissolve 0.2 mmol of H2ONDI in a reaction vessel containing 10 ml of DMF, then weigh 0.2 mmol of nickel nitrate, dissolve it in 10 ml of deionized water and add it to the reaction vessel. Mix well and place the reaction vessel in an oven to react. Start from room temperature and heat up to 100℃. Keep the temperature for 48 h. After the reaction is completed, cool to room temperature. After filtering the product, wash and dry it with deionized water and DMF. The precipitate is dried in a vacuum drying oven at 60℃ for 12 h to obtain N,N'-dihydroxynaphthalimide nickel coordination polymer (i.e., Ni-ONDI).

[0076] The thermogravimetric curves of the N,N'-dihydroxynaphthalimide nickel coordination polymer and N,N'-dihydroxynaphthalimide obtained in this embodiment are shown below. Figure 1 As shown, the infrared absorption spectrum is as follows: Figure 2 As shown, the X-ray diffraction analysis pattern is as follows: Figure 3 As shown in the figure, the prepared N,N'-dihydroxynaphthalimide nickel coordination polymer is different from N,N'-dihydroxynaphthalimide and is a new composite material, as indicated by thermogravimetric curves, infrared absorption spectra and X-ray diffraction analysis.

[0077] Performance testing of the N,N'-dihydroxynaphthalimide nickel coordination polymer obtained in this embodiment as a cathode material for lithium / sodium-ion batteries:

[0078] (1) Ni-ONDI, super P, and polyvinylidene fluoride were ground and mixed in an agate mortar at a mass ratio of 6:3:1 for 10 min. Then, an appropriate amount of NMP solution was added dropwise and the grinding continued for another 10 min. The resulting slurry was coated onto aluminum foil, dried in a vacuum drying oven at 60°C for 12 h, and cut into discs to obtain the positive electrode of a lithium / sodium ion battery. The content of the electrode active material Ni-ONDI was approximately 1.0 mg.

[0079] (2) A two-electrode system is used. The working electrode prepared in step (1) is the positive electrode, the lithium sheet is the negative electrode, the glass fiber is the separator, and 1M LiTFSI-DOL+DME (VDOL:VDME=1:1) is the electrolyte. The button cell is assembled in a glove box filled with argon gas.

[0080] (3) Constant current charge-discharge test, the test conditions are: constant current charge-discharge density is 100 mA·g -1 The charge / discharge potential range is 1.5V-3.8V. All charge / discharge performance tests were performed at room temperature.

[0081] (4) Replace the negative electrode material with a sodium sheet and the electrolyte with NaPF6-DME, and repeat steps (1) to (3). The charge / discharge potential range is 1-3.5V. All charge / discharge performance tests were performed at room temperature.

[0082] The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide nickel coordination polymer electrode with lithium sheet as the negative electrode, obtained by testing, are shown below. Figure 4 and Figure 5 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 133.1 mAh·g. -1 The first-round Coulomb efficiency was 101.55%. (100mA·g) -1 After 300 cycles at the current density, the reversible capacity is 92.7 mAh·g. -1The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide nickel coordination polymer electrode with sodium sheet as the negative electrode, obtained by testing, are shown below. Figure 6 and Figure 7 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 142.2 mAh·g. -1 The first-lap coulomb efficiency was 93.7%. (100mA·g) -1 After 200 cycles at the current density, the reversible capacity is 132.5 mAh·g. -1 .

[0083] The results above show that the N,N'-dihydroxynaphthalimide nickel coordination polymer obtained in this embodiment has excellent electrochemical performance as a cathode material for lithium / sodium ion batteries.

[0084] Example 2

[0085] This embodiment proposes an imide-based conductive conjugated coordination polymer, which is prepared by the following steps:

[0086] (1) 10 mmol of 1,4,5,8-naphthalenetetracarboxylic anhydride and 21 mmol of hydroxylamine hydrochloride were added to 20 ml of DMF and mixed evenly. The mixture was refluxed at 65 °C for 8 h. The crude product was filtered, washed and dried to obtain N,N'-dihydroxynaphthalenediimide (H2ONDI).

[0087] (2) Dissolve 0.2 mmol of H2ONDI in a reaction vessel containing 10 ml of DMF, then weigh 0.2 mmol of manganese chloride, dissolve it in 10 ml of deionized water and add it to the reaction vessel. Mix well and place the reaction vessel in an oven to react. Start from room temperature and heat up to 100℃. Keep the temperature for 48 h. After the reaction is completed, cool to room temperature. After filtering the product, wash and dry it with deionized water and DMF. The precipitate is dried in a vacuum drying oven at 60℃ for 12 h to obtain N,N'-dihydroxynaphthalimide manganese coordination polymer (i.e., Mn-ONDI).

[0088] The thermogravimetric curves of the N,N'-dihydroxynaphthalimide manganese coordination polymer and N,N'-dihydroxynaphthalimide obtained in this embodiment are shown below. Figure 8 As shown, the infrared absorption spectrum is as follows: Figure 9 As shown, the X-ray diffraction analysis pattern is as follows: Figure 10 As shown in the figure, the thermogravimetric curve, infrared absorption spectrum and X-ray diffraction analysis show that the prepared N,N'-dihydroxynaphthalimide manganese coordination polymer is different from N,N'-dihydroxynaphthalimide and is a new composite material.

[0089] Performance testing of the N,N'-dihydroxynaphthalimide manganese coordination polymer obtained in this embodiment as a cathode material for lithium / sodium-ion batteries:

[0090] (1) Mn-ONDI, super P, and polyvinylidene fluoride were ground and mixed in an agate mortar at a mass ratio of 6:3:1 for 10 min. Then, an appropriate amount of NMP solution was added dropwise and the mixture was ground for another 10 min. The resulting slurry was coated onto aluminum foil, dried in a vacuum drying oven at 60°C for 12 h, and cut into discs to obtain the positive electrode of a lithium / sodium ion battery. The content of the electrode active material Mn-ONDI was approximately 1.0 mg.

[0091] (2) A two-electrode system is used. The working electrode prepared in step (1) is the positive electrode, the lithium sheet is the negative electrode, the glass fiber is the separator, and 1M LiTFSI-DOL+DME (VDOL:VDME=1:1) is the electrolyte. The button cell is assembled in a glove box filled with argon gas.

[0092] (3) Constant current charge-discharge test, the test conditions are: constant current charge-discharge density is 100 mA·g -1 The charge / discharge potential range is 1.5V-3.8V. All charge / discharge performance tests were performed at room temperature.

[0093] (4) Replace the negative electrode material with a sodium sheet and the electrolyte with NaPF6-DME, and repeat steps (1) to (3). The charge / discharge potential range is 1-3.6V. All charge / discharge performance tests were performed at room temperature.

[0094] The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide manganese coordination polymer electrode with lithium sheet as the negative electrode, obtained by testing, are shown below. Figure 11 and Figure 12 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 91.9 mAh·g. -1 The first-lap Coulomb efficiency was 127.26%. (100mA·g) -1 After 500 cycles at the current density, the reversible capacity is 89.4 mAh·g. -1 The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide manganese coordination polymer electrode with sodium sheet as the negative electrode, obtained by testing, are shown below. Figure 13 and Figure 14 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 88.7 mAh·g. -1 The first-lap coulomb efficiency was 114.4%. (100mA·g) -1 After 200 cycles at the current density, the reversible capacity is 126.4 mAh·g. -1 .

[0095] The results above show that the N,N'-dihydroxynaphthalimide manganese coordination polymer obtained in this embodiment has excellent electrochemical performance as a cathode material for lithium / sodium ion batteries.

[0096] Example 3

[0097] This embodiment proposes an imide-based conductive conjugated coordination polymer, which is prepared by the following steps:

[0098] (1) 10 mmol of 1,4,5,8-naphthalenetetracarboxylic anhydride and 21 mmol of hydroxylamine hydrochloride were added to 20 ml of DMF and mixed evenly. The mixture was refluxed at 65 °C for 8 h. The crude product was filtered, washed and dried to obtain N,N'-dihydroxynaphthalenediimide (H2ONDI).

[0099] (2) Dissolve 0.2 mmol of H2ONDI in a reaction vessel containing 10 ml of DMF, then weigh 0.2 mmol of calcium nitrate, dissolve it in 10 ml of deionized water and add it to the reaction vessel. Mix well and place the reaction vessel in an oven to react. Start from room temperature and heat up to 100℃. Keep the temperature for 48 h. After the reaction is completed, cool to room temperature. After filtering the product, wash and dry it with deionized water and DMF. The precipitate is dried in a vacuum drying oven at 60℃ for 12 h to obtain N,N'-dihydroxynaphthalimide calcium coordination polymer (i.e., Ca-ONDI).

[0100] The thermogravimetric curves of the N,N'-dihydroxynaphthalimide calcium coordination polymer and N,N'-dihydroxynaphthalimide obtained in this embodiment are shown below. Figure 15 As shown, the infrared absorption spectrum is as follows: Figure 16 As shown, the X-ray diffraction analysis pattern is as follows: Figure 17 As shown in the figure, the prepared N,N'-dihydroxynaphthalimide calcium coordination polymer is different from N,N'-dihydroxynaphthalimide and is a new composite material, as indicated by thermogravimetric curves, infrared absorption spectra and X-ray diffraction analysis.

[0101] Performance testing of the N,N'-dihydroxynaphthalimide calcium coordination polymer obtained in this embodiment as a cathode material for lithium / sodium-ion batteries:

[0102] (1) Ca-ONDI, super P, and polyvinylidene fluoride were ground and mixed in an agate mortar at a mass ratio of 6:3:1 for 10 min. Then, an appropriate amount of NMP solution was added dropwise and the grinding continued for another 10 min. The resulting slurry was coated onto aluminum foil, dried in a vacuum drying oven at 60°C for 12 h, and cut into discs to obtain the positive electrode of a lithium / sodium ion battery. The content of the electrode active material Ca-ONDI was approximately 1.0 mg.

[0103] (2) A two-electrode system is used. The working electrode prepared in step (1) is the positive electrode, the lithium sheet is the negative electrode, the glass fiber is the separator, and 1M LiTFSI-DOL+DME (VDOL:VDME=1:1) is the electrolyte. The button cell is assembled in a glove box filled with argon gas.

[0104] (3) Constant current charge-discharge test, the test conditions are: constant current charge-discharge density is 100 mA·g -1 The charge / discharge potential range is 1V-3.5V. All charge / discharge performance tests were performed at room temperature.

[0105] (4) Replace the negative electrode material with a sodium sheet and the electrolyte with NaPF6-DME, and repeat steps (1) to (3). The charge / discharge potential range is 1-3.6V. All charge / discharge performance tests were performed at room temperature.

[0106] The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide calcium coordination polymer electrode with lithium sheet as the negative electrode obtained by testing are shown below. Figure 18 and Figure 19 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 56.6 mAh·g. -1 The first-lap coulomb efficiency was 122%. (100mA·g) -1 After 200 cycles at the current density, the reversible capacity is 56.8 mAh·g. -1 The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide calcium coordination polymer electrode with sodium sheet as the negative electrode, obtained by testing, are shown below. Figure 20 and Figure 21 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 69.6 mAh·g. -1 The first-lap coulomb efficiency was 131.96%. (100mA·g) -1 After 300 cycles at the current density, the reversible capacity is 106.3 mAh·g. -1 .

[0107] The results above show that the N,N'-dihydroxynaphthalimide calcium coordination polymer obtained in this embodiment has excellent electrochemical performance as a cathode material for lithium / sodium ion batteries.

[0108] Example 4

[0109] This embodiment proposes an imide-based conductive conjugated coordination polymer, which is prepared by the following steps:

[0110] (1) 10 mmol of 1,4,5,8-naphthalenetetracarboxylic anhydride and 21 mmol of hydroxylamine hydrochloride were added to 20 ml of DMF and mixed evenly. The mixture was refluxed at 65 °C for 8 h. The crude product was filtered, washed and dried to obtain N,N'-dihydroxynaphthalenediimide (H2ONDI).

[0111] (2) Dissolve 0.2 mmol of H2ONDI in a reaction vessel containing 10 ml of DMF, then weigh 0.2 mmol of copper nitrate, dissolve it in 10 ml of deionized water and add it to the reaction vessel. Mix well and place the reaction vessel in an oven to react. Start from room temperature and heat to 100℃, keep the temperature for 48 h. After the reaction is completed, cool to room temperature. After filtering the product, wash and dry it with deionized water and DMF. The precipitate is dried in a vacuum drying oven at 60℃ for 12 h to obtain N,N'-dihydroxynaphthalene diimide copper coordination polymer (i.e., Cu-ONDI).

[0112] The thermogravimetric curves of the N,N'-dihydroxynaphthalimide copper coordination polymer and N,N'-dihydroxynaphthalimide obtained in this embodiment are shown below. Figure 22 As shown, the infrared absorption spectrum is as follows: Figure 23 As shown, the X-ray diffraction analysis pattern is as follows: Figure 24 As shown in the figure, the prepared N,N'-dihydroxynaphthalimide copper coordination polymer is different from N,N'-dihydroxynaphthalimide and is a new composite material, as indicated by thermogravimetric curves, infrared absorption spectra and X-ray diffraction analysis.

[0113] Performance testing of the N,N'-dihydroxynaphthalimide copper coordination polymer obtained in this embodiment as a cathode material for lithium / sodium-ion batteries:

[0114] (1) Cu-ONDI, super P, and polyvinylidene fluoride were ground and mixed in an agate mortar at a mass ratio of 6:3:1 for 10 min. Then, an appropriate amount of NMP solution was added dropwise and the grinding continued for another 10 min. The resulting slurry was coated onto aluminum foil, dried in a vacuum drying oven at 60°C for 12 h, and cut into discs to obtain the positive electrode of a lithium / sodium ion battery. The content of the electrode active material Cu-ONDI was approximately 1.0 mg.

[0115] (2) A two-electrode system is used. The working electrode prepared in step (1) is the positive electrode, the lithium sheet is the negative electrode, the glass fiber is the separator, and 1M LiTFSI-DOL+DME (VDOL:VDME=1:1) is the electrolyte. The button cell is assembled in a glove box filled with argon gas.

[0116] (3) Constant current charge-discharge test, the test conditions are: constant current charge-discharge density is 100 mA·g -1The charge / discharge potential range is 1.5V-3.8V. All charge / discharge performance tests were performed at room temperature.

[0117] (4) Replace the negative electrode material with a sodium sheet and the electrolyte with NaPF6-DME, and repeat steps (1) to (3). The charge / discharge potential range is 1-3.6V. All charge / discharge performance tests were performed at room temperature.

[0118] The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide copper coordination polymer electrode with lithium sheet as the negative electrode obtained by testing are shown below. Figure 25 and Figure 26 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 170.4 mAh·g. -1 The first-lap coulomb efficiency was 101.76%. (100mA·g) -1 After 120 cycles at the current density, the reversible capacity is 101.3 mAh·g. -1 The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide copper coordination polymer electrode with sodium sheet as the negative electrode, obtained by testing, are shown below. Figure 27 and Figure 28 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 98.9 mAh·g. -1 The first-lap Coulomb efficiency was 127.49%. (100mA·g) -1 After 200 cycles at the current density, the reversible capacity is 150.4 mAh·g. -1 .

[0119] The results above show that the N,N'-dihydroxynaphthalimide copper coordination polymer obtained in this embodiment has excellent electrochemical performance as a cathode material for lithium / sodium ion batteries.

[0120] Example 5

[0121] This embodiment proposes an imide-based conductive conjugated coordination polymer, which is prepared by the following steps:

[0122] (1) 10 mmol of 1,4,5,8-naphthalenetetracarboxylic anhydride and 21 mmol of hydroxylamine hydrochloride were added to 20 ml of DMF and mixed evenly. The mixture was refluxed at 65 °C for 8 h. The crude product was filtered, washed and dried to obtain N,N'-dihydroxynaphthalenediimide (H2ONDI).

[0123] (2) Dissolve 0.2 mmol of H2ONDI in a reaction vessel containing 10 ml of DMF, then weigh 0.2 mmol of cobalt chloride, dissolve it in 10 ml of deionized water and add it to the reaction vessel. Mix well and place the reaction vessel in an oven to react. Start from room temperature and heat up to 100℃, keep the temperature for 48 h. After the reaction is completed, cool to room temperature. After filtering the product, wash and dry it with deionized water and DMF. The precipitate is dried in a vacuum drying oven at 60℃ for 12 h to obtain N,N'-dihydroxynaphthalimide cobalt coordination polymer (i.e., Co-ONDI).

[0124] The thermogravimetric curves of the N,N'-dihydroxynaphthalimide cobalt coordination polymer and N,N'-dihydroxynaphthalimide obtained in this embodiment are shown below. Figure 29 As shown, the infrared absorption spectrum is as follows: Figure 30 As shown, the X-ray diffraction analysis pattern is as follows: Figure 31 As shown in the figure, the prepared N,N'-dihydroxynaphthalimide cobalt coordination polymer is different from N,N'-dihydroxynaphthalimide and is a new composite material, as indicated by thermogravimetric curves, infrared absorption spectra and X-ray diffraction analysis.

[0125] Performance testing of the N,N'-dihydroxynaphthalimide cobalt coordination polymer obtained in this embodiment as a cathode material for lithium / sodium-ion batteries:

[0126] (1) Co-ONDI, super P, and polyvinylidene fluoride were ground and mixed in an agate mortar at a mass ratio of 6:3:1 for 10 min. Then, an appropriate amount of NMP solution was added dropwise and the grinding continued for another 10 min. The resulting slurry was coated onto aluminum foil, dried in a vacuum drying oven at 60°C for 12 h, and cut into discs to obtain the positive electrode of a lithium / sodium ion battery. The content of the electrode active material Co-ONDI was approximately 1.0 mg.

[0127] (2) A two-electrode system is used. The working electrode prepared in step (1) is the positive electrode, the lithium sheet is the negative electrode, the glass fiber is the separator, and 1M LiTFSI-DOL+DME (VDOL:VDME=1:1) is the electrolyte. The button cell is assembled in a glove box filled with argon gas.

[0128] (3) Constant current charge-discharge test, the test conditions are: constant current charge-discharge density is 100 mA·g -1 The charge / discharge potential range is 1.5V-4V. All charge / discharge performance tests were performed at room temperature.

[0129] (4) Replace the negative electrode material with a sodium sheet and the electrolyte with NaPF6-DME, and repeat steps (1) to (3). The charge / discharge potential range is 1-3.6V. All charge / discharge performance tests were performed at room temperature.

[0130] The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide cobalt coordination polymer electrode with lithium sheet as the negative electrode, obtained by testing, are shown below. Figure 32 and Figure 33 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 112.2 mAh·g. -1 The first lap coulomb efficiency was 97.41%. (100mA·g) -1 After 200 cycles at the current density, the reversible capacity is 59.9 mAh·g. -1 The constant current charge-discharge curves and cycle capacity diagrams of the N,N'-dihydroxynaphthalimide cobalt coordination polymer electrode with sodium sheet as the negative electrode, obtained by testing, are shown below. Figure 34 and Figure 35 As shown. The electrochemical performance test results are as follows: the initial discharge specific capacity is 133 mAh·g. -1 The first lap coulomb efficiency was 91.58%. (100mA·g) -1 After 100 cycles at the current density, the reversible capacity is 132.5 mAh·g. -1 .

[0131] The results above show that the N,N'-dihydroxynaphthalimide cobalt coordination polymer obtained in this embodiment has excellent electrochemical performance as a cathode material for lithium / sodium ion batteries.

[0132] Compared with the prior art, the beneficial effects of the present invention also include:

[0133] 1) The method of the present invention adopts a simple one-step hydrothermal method to prepare N,N'-dihydroxynaphthalimide conductive conjugated coordination polymer. The synthesis route is very simple, easy to process, has low equipment requirements, and is environmentally friendly.

[0134] 2) The charge-discharge curves and cycle performance of the N,N'-dihydroxynaphthalimide conductive conjugated coordination polymer of the present invention as a positive electrode material for lithium / sodium ion batteries show that it has extremely superior electrochemical performance.

[0135] 3) The N,N'-dihydroxynaphthalimide conductive conjugated coordination polymer of the present invention does not contain polluting or radioactive heavy metal ions, is environmentally friendly, green and environmentally friendly, and has low cost.

[0136] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. The application of an imide-based conductive conjugated coordination polymer as a cathode material for lithium-ion batteries or sodium-ion batteries, characterized in that, The imide-based conductive conjugated coordination polymer is prepared by the following steps: N,N'-Dihydroxynaphthalimide is added to a solvent, followed by the addition of a metal salt and heating to obtain an imide-based conductive conjugated coordination polymer; the molar ratio of N,N'-dihydroxynaphthalimide to the metal salt is 1:(1-1.5); the heating reaction is carried out at 100°C for 48 hours; the solvent is DMF; the metal salt is one or more of soluble nickel salt, soluble copper salt, and soluble cobalt salt.

2. The application according to claim 1, characterized in that, The soluble nickel salt includes nickel nitrate; the soluble copper salt includes copper nitrate; and the soluble cobalt salt includes cobalt chloride.

3. The application according to claim 1, characterized in that, The N,N'-dihydroxynaphthalimide is prepared by the following steps: The N,N'-dihydroxynaphthalenediimide was obtained by mixing and heating 1,4,5,8-naphthalenetetracarboxylic anhydride and hydroxylamine hydrochloride in a solvent.

4. The application according to claim 3, characterized in that, The molar ratio of 1,4,5,8-naphthalenetetracarboxylic anhydride to hydroxylamine hydrochloride is 1:(2-2.5); and / or the mixing and heating temperature is 65~70℃, and the time is 5-7h.

5. The application according to claim 1, characterized in that, The imide-based conductive conjugated coordination polymer, super P, and polyvinylidene fluoride are ground and mixed, and then NMP solution is added dropwise to continue grinding. The resulting slurry is coated onto aluminum foil and vacuum dried to obtain a lithium-ion battery cathode or a sodium-ion battery cathode.

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