A phenazine derivative negative electrode material and its preparation method and application

Abstract

The present invention relates to the technical field of aqueous battery materials, and specifically discloses a novel phenazine derivative negative electrode material for aqueous batteries, including novel phenazine derivatives having the following structure: wherein R is one of hydrogen ion, oxygen anion, dialkylamino, alkylamino, amino, hydroxyl, alkoxy, amide, acyloxy, alkyl, carboxymethyl, phenyl, tertiary amine cation, nitro, trihalomethyl, cyano, sulfonic acid, formyl, acyl, and carboxyl. When the novel phenazine derivative negative electrode material of the present invention is used as a negative electrode material for aqueous batteries, it can exist in an alkaline electrolyte for a long time without dissolving, can improve the battery cycle life, and the theoretical specific capacity can reach more than 400 mAh g ‑1 , which is more than 1.5 times that of phenazine and much higher than the current aqueous battery electrode materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of aqueous battery materials, and in particular relates to a novel phenazine derivative negative electrode material for aqueous batteries, and a preparation method and application thereof. Background Art

[0002] At present, a large part of my country's fossil energy such as oil and natural gas is imported from abroad. For a long time, energy issues have been one of the important issues of economic development. With the development of renewable energy and clean energy, there is a demand for large-scale energy storage. Large-scale and efficient energy storage technology is an important way to solve the non-steady-state characteristics of renewable energy generation. In addition, with the vigorous development of portable electronic devices and various automobiles, higher requirements are placed on energy storage equipment. In the past few decades, people have developed flexible alkali metal ion batteries (Li, Na, K). The advantage of this type of battery is its high energy density, but there are also a series of problems, such as high production cost and toxic organic electrolytes, which limit its development.

[0003] An important component of electrochemical energy storage devices is secondary aqueous batteries. The biggest feature of this type of battery is the use of aqueous electrolytes. Compared with organic electrolytes, this electrolyte has the advantages of higher conductivity, higher safety, and lower production cost. At present, phenazine has been used as a negative electrode material in aqueous batteries, but its low energy density limits its development and application. Developing a new type of aqueous negative electrode material that is simple, cheap, safe, high in specific capacity, and high in material stability is of great significance to promoting the development and application of aqueous batteries. Summary of the invention

[0004] The object of the present invention is to provide a novel phenazine derivative negative electrode material and an aqueous battery. The novel phenazine derivative negative electrode material has the advantages of high specific capacity and high stability.

[0005] To achieve the above object, the present invention provides a novel phenazine derivative negative electrode material for an aqueous battery, comprising a novel phenazine derivative, wherein the novel phenazine derivative has the following structure:

[0006]

[0007] Among them, R is one of hydrogen ion, oxygen anion, dialkylamino, alkylamino, amino, hydroxyl, alkoxy, amide, acyloxy, alkyl, carboxymethyl, phenyl, tertiary amine cation, nitro, trihalomethyl, cyano, sulfonic acid, formyl, acyl, and carboxyl.

[0008] Preferably, in the above-mentioned novel phenazine derivative negative electrode material, the synthesis method of the novel phenazine derivative comprises the following steps:

[0009] Under argon protection, cyclohexanone octahydrate and 3,4-diaminobenzene substitution are added to a reaction solvent and mixed to obtain a mixture, and the mixture is stirred and reacted at 120-130° C. for 20-25 hours; the reaction mixture is filtered, washed, and vacuum dried to obtain a novel phenazine derivative.

[0010] The synthetic chemical reaction formula of the novel phenazine derivative is as follows:

[0011]

[0012] Preferably, in the above-mentioned novel phenazine derivative negative electrode material, the reaction solvent is an ethanol / acetic acid mixed solvent with a volume ratio of 1:1, and the molar ratio of the cyclohexanone octahydrate and the 3,4-diaminobenzene substituent is 1:3-4.

[0013] Preferably, in the above-mentioned new phenazine derivative negative electrode material, the mixture is stirred and reacted at 125°C for 24 hours, the reaction mixture is filtered while hot, and washed twice with acetic acid to obtain a powdery crude product; then it is rinsed with water, ethanol, and acetone, and vacuum dried to obtain a new phenazine derivative.

[0014] The present invention also provides a method for preparing the novel phenazine derivative negative electrode material, comprising the following steps:

[0015] (1) dissolving the novel phenazine derivative in a hydrochloric acid solution, adding a conductive agent, vigorously stirring for 0.1-1h, then ultrasonically treating for 20-40min, placing the mixture under vacuum conditions, and adding a NaOH solution to the mixture at a certain drop rate; filtering the precipitate, washing, and drying to obtain a nano-sized novel phenazine derivative / conductive agent composite material;

[0016] (2) grinding the novel phenazine derivative / conductive agent composite material for 10 to 30 minutes, pressing it between two layers of nickel foam, and then rolling it to obtain a rolled electrode;

[0017] (3) Add a binder dropwise onto the rolled electrode sheet and then dry the rolled electrode sheet to obtain a novel phenazine derivative negative electrode material.

[0018] Preferably, in the preparation method of the above-mentioned novel phenazine derivative negative electrode material, in the step (1), the conductive agent is at least one of Super P, carbon nanotubes, and acetylene black having a porous structure, the mass ratio of the novel phenazine derivative to the conductive agent is 7-9.5:0.5-3, the molar ratio of the novel phenazine derivative to hydrochloric acid is 1:200-300, the molar ratio of hydrochloric acid to sodium hydroxide is 1:1.2-1.3, and the dripping rate is 0.01-0.25 ml / min.

[0019] Preferably, in the method for preparing the novel phenazine derivative negative electrode material, in step (2), the roller pressing pressure is 1.3-1.5 g / cm 3 .

[0020] The present invention also provides application of the novel phenazine derivative negative electrode material, wherein the novel phenazine derivative negative electrode material is used as a negative electrode of an aqueous battery.

[0021] The present invention also provides an aqueous battery comprising a positive electrode, a negative electrode, a separator and an electrolyte, wherein the negative electrode is a novel phenazine derivative negative electrode material prepared by the preparation method of the novel phenazine derivative negative electrode material.

[0022] Preferably, in the above aqueous battery, the positive electrode material is nickel hydroxide or activated carbon, the diaphragm is made of hard glass fiber, and the electrolyte is sodium hydroxide solution or potassium hydroxide solution.

[0023] Preferably, in the above aqueous battery, the molar concentration of the electrolyte is 5-7 mol / L.

[0024] Preferably, in the above aqueous battery, the assembly method is that the negative electrode material is coated with a diaphragm in the middle, and the upper and lower layers are fixed with a positive electrode to form a sandwich-type electrode group.

[0025] Compared with the existing technology, the present invention has the following beneficial effects:

[0026] 1. The novel phenazine derivative negative electrode material of the present invention, when used as the negative electrode material of aqueous batteries, can exist in alkaline electrolyte for a long time without dissolving, which can improve the battery cycle life, and the theoretical specific capacity can reach more than 400 mAh g -1 , which is more than 1.5 times that of phenazine and much higher than the current aqueous battery electrode materials. It has high specific capacity and strong material stability.

[0027] 2. The new phenazine derivative negative electrode material of the present invention, the active substance new phenazine derivative is highly safe, pollution-free, easy to synthesize, and has abundant raw material resources and low price; in the preparation method of the new phenazine derivative negative electrode material, the rolling method is adopted to make the new phenazine derivative / conductive agent composite material firmly combined with the nickel foam; the whole preparation method has the advantages of simple process, low cost, low energy consumption, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the NMR spectrum of the new phenazine derivative in Example 1 of the present invention.

[0029] Figure 2 The cyclic voltammograms of the negative electrode materials of Example 2 of the present invention and Comparative Example 1 are shown.

[0030] Figure 3The battery cycle capacity diagram of Example 3 of the present invention and Comparative Example 2. DETAILED DESCRIPTION

[0031] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0032] The novel phenazine derivative of the present invention has the following structural formula:

[0033]

[0034] Among them, R is one of hydrogen ion, oxygen anion, dialkylamino, alkylamino, amino, hydroxyl, alkoxy, amide, acyloxy, alkyl, carboxymethyl, phenyl, tertiary amine cation, nitro, trihalomethyl, cyano, sulfonic acid, formyl, acyl, and carboxyl.

[0035] The synthesis method of the novel phenazine derivative of the present invention comprises the following steps:

[0036] Under argon protection, cyclohexanone octahydrate reacts with 3,4-diaminobenzene substitution, and the reaction solvent is a mixed solvent of ethanol / acetic acid with a volume ratio of 1:1. The mixture is stirred at 125°C for 24 hours. The reaction mixture is filtered while hot and washed with acetic acid twice to obtain a powdery crude product. Then it is washed with water, ethanol, and acetone and vacuum dried to obtain a new phenazine derivative. The chemical reaction is as follows:

[0037]

[0038] Example 1

[0039] A novel phenazine derivative for aqueous batteries, wherein R in the structural formula of the novel phenazine derivative is a hydrogen ion, the novel phenazine derivative is named DZP, and the synthesis method comprises the following steps:

[0040] Under argon protection, 2.0 g of cyclohexanone octahydrate, 2.28 g of o-phenylenediamine, and 100 mL of a mixed solvent of ethanol / acetic acid (volume ratio = 1:1) were added to a 250 mL flask, and the mixture was stirred at 125 ° C for 24 hours under argon protection. The reaction mixture was filtered while hot and washed with 30 mL of hot acetic acid twice to obtain a powdery crude product. Then it was washed with water, ethanol, and acetone and vacuum dried to obtain 2.23 g of the product with a yield of 90.6%. The NMR spectrum is characterized as follows Figure 1 .

[0041] Example 2

[0042] A novel phenazine derivative negative electrode material for an aqueous battery comprises a novel phenazine derivative and a conductive agent, wherein the conductive agent is Super P, and the novel phenazine derivative is DZP synthesized in Example 1 and used as an active substance of the aqueous battery negative electrode material.

[0043] The method for preparing the novel phenazine derivative negative electrode material for aqueous batteries of this embodiment comprises the following steps:

[0044] (1) 2.8 g of DZP was dissolved in 365 mL of 5 mol / L hydrochloric acid solution under magnetic stirring, and 0.5 g of SuperP was added and mixed. The mixture was stirred at 1000 rpm for 10 min, and then ultrasonically treated for 30 min. The mixture was placed under vacuum and kept for 30 min to allow the DZP solution to fully infiltrate the pores of Super P. In order to allow the DZP in the hydrochloric acid solution to slowly precipitate and uniformly deposit on the surface of the porous Super P in nanometer size, a peristaltic pump was used at a speed of 0.2 mL min -1 Slowly add 456mL of 5mol / LNaOH solution to the above mixed system at a speed of 100 μL; filter the precipitate, wash it with deionized water for 3 times, and freeze-dry it for 24 hours to obtain a nano-sized DZP / Super P composite material;

[0045] (2) The DZP / Super P composite material was ground in a mortar for 20 min and pressed between two layers of nickel foam at a pressure of 1.3 g / cm 3 The DZP / Super P composite material is compacted and rolled to firmly combine with the nickel foam to obtain a rolled pole piece;

[0046] (3) 0.25 g of 60 wt% polytetrafluoroethylene concentrated dispersion binder was dripped onto the rolled electrode sheet, and then dried to obtain a novel phenazine derivative negative electrode material (DZP / Super P negative electrode material).

[0047] Example 3

[0048] An aqueous battery, wherein nickel hydroxide is used as a positive electrode material, a new phenazine derivative negative electrode material prepared in Example 1 and wrapped with hard glass fiber is used in the middle as a negative electrode, the upper and lower layers are clamped by nickel hydroxide positive electrode sheets, nickel tabs are welded on them respectively, the outer layer is packaged with an aluminum plastic film, and the opening is not completely sealed, and sufficient 6 mol / L sodium hydroxide electrolyte is added to obtain an aqueous battery. After standing for 24 hours, a performance test is performed.

[0049] Comparative Example 1

[0050] The preparation method is the same as that in Example 1, except that the active material of the negative electrode material is replaced with phenazine to prepare a phenazine / Super P negative electrode material.

[0051] Comparative Example 2

[0052] The experimental steps were the same as those in Example 3, except that the negative electrode was replaced with a phenazine / Super P negative electrode composite material to prepare a phenazine / nickel battery.

[0053] Test Example 1

[0054] (I) Cyclic voltammetry test

[0055] A three-electrode system was used, with DZP / Super P negative electrode material (Example 2) or phenazine / Super P composite material (Comparative Example 1), nickel hydroxide and calomel electrode as working electrode, counter electrode and reference electrode respectively, 6 mol / L alkaline sodium hydroxide was used as electrolyte, the working potential was -2V-1V, and the test results are shown in Figure 2 .

[0056] Depend on Figure 2 It can be seen that the redox potentials of the cyclic voltammetry curves of the phenazine / Super P composite electrode are at -0.5V and -1.2V, respectively. The cyclic voltammetry curve of the DZP / Super P negative electrode material electrode has two separate reduction peaks at -1.0V, which are -0.8V and -1.25V, respectively, showing a two-step electrochemical cathode reaction. The redox current of the DZP / Super P composite is smaller than that of the phenazine / Super P composite, indicating that the reversibility of the DZP / Super P composite is better. The redox potential difference of the DZP / Super P composite is smaller than that of the phenazine / Super P composite, indicating that the polarization of the DZP / Super P composite is smaller.

[0057] (II) Cycle test

[0058] At a constant temperature of 25 degrees, DZP / Super P and phenazine / Super P batteries were activated for 5 weeks at a low rate of 0.1C and then charged and discharged at a constant current rate of 0.5C for 500 cycles. The test results are shown in Figure 3 .

[0059] from Figure 3 It can be seen that the initial discharge gram capacity of DZP / Super P and phenazine / Super P batteries are 399mAh / g and 281mAh / g, respectively, and the initial discharge gram capacity of DZP / Super P battery is about 1.4 times that of phenazine / Super P battery. As the number of cycles increases, the capacity retention rates of DZP / Super P and phenazine / Super P are comparable. When the cycle reaches 500 cycles, the capacity retention rate is about 90%, indicating that DZP / Super P and phenazine / Super P, as negative electrode materials for aqueous batteries, can exist stably in alkaline electrolytes and have long cycle characteristics.

[0060] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. An application of a phenazine derivative negative electrode material for an aqueous battery, characterized in that: The phenazine derivative negative electrode material is used as the negative electrode of an aqueous battery. The phenazine derivative negative electrode material comprises a phenazine derivative, and the phenazine derivative has the following structure: Wherein, R is a formyl group.

2. The use of the phenazine derivative negative electrode material according to claim 1, characterized in that: The method for preparing the phenazine derivative negative electrode material comprises the following steps: (1) dissolving the phenazine derivative in a hydrochloric acid solution, adding a conductive agent, vigorously stirring for 0.1-1h, then ultrasonically treating for 20-40min, placing the mixture under vacuum conditions and allowing it to stand, and adding a NaOH solution to the mixture at a certain drop rate; filtering the precipitate, washing, and drying to obtain a nano-phenazine derivative / conductive agent composite material; (2) grinding the phenazine derivative / conductive agent composite material for 10 to 30 minutes, pressing it between two layers of nickel foam, and then rolling it to obtain a rolled electrode; (3) Add a binder dropwise onto the rolled electrode sheet, followed by drying to obtain a phenazine derivative negative electrode material.

3. The use of the phenazine derivative negative electrode material according to claim 2, characterized in that: In the step (1), the conductive agent is at least one of Super P with a porous structure, carbon nanotubes, and acetylene black, the mass ratio of the phenazine derivative to the conductive agent is 7-9.5:0.5-3, the molar ratio of the phenazine derivative to hydrochloric acid is 1:200-300, the molar ratio of hydrochloric acid to sodium hydroxide is 1:1.2-1.3, and the dripping rate is 0.01-0.25 ml / min.

4. The use of the phenazine derivative negative electrode material according to claim 2, characterized in that: In step (2), the roller pressing pressure is 1.3-1.5 g / cm 3 .

5. An aqueous battery, characterized in that: It comprises a positive electrode, a negative electrode, a separator and an electrolyte, wherein the negative electrode is a phenazine derivative negative electrode material, the phenazine derivative negative electrode material comprises a phenazine derivative, and the phenazine derivative has the following structure: Wherein, R is a formyl group.

6. The aqueous battery according to claim 5, characterized in that: The positive electrode material is nickel hydroxide or activated carbon, the diaphragm is made of hard glass fiber, the electrolyte is sodium hydroxide solution or potassium hydroxide solution, and the molar concentration of the electrolyte is 5-7 mol / L.

7. The aqueous battery according to claim 5, characterized in that: The assembly method is to use a diaphragm to cover the negative electrode material in the middle, and the upper and lower layers are fixed with positive electrodes to form a sandwich-type electrode group.

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