Multi-nitryl conjugated small organic molecule electrode material as well as preparation method and application of multi-nitryl conjugated small organic molecule electrode material
By designing the polynitro conjugated organic small molecule electrode material HATN-6NO2, the problems of low capacity and rate performance of aqueous ammonium ion battery electrode materials were solved, achieving high capacity and stable electrochemical performance, which is suitable for the application of aqueous ammonium ion batteries.
Patent Information
- Application Number
- CN202510981199.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-16
- Publication Date
- 2025-12-12
AI Technical Summary
Existing aqueous ammonium-ion battery electrode materials suffer from low capacity and poor rate performance, which affects their application in large-scale energy storage scenarios.
A polynitro conjugated organic small molecule electrode material, HATN-6NO2, was designed. By introducing nitro groups into the conjugated structure, redox active sites are increased while maintaining structural stability, thereby improving electron transfer and charge storage capabilities.
It achieves high specific capacity and good cycle stability, improving the electrochemical performance of aqueous ammonium ion batteries, especially maintaining high discharge capacity and coulombic efficiency even at high current densities.
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Figure CN121108145A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of aqueous battery electrodes, and particularly relates to a polynitro conjugated organic small molecule electrode material, its preparation method, and its application. Background Technology
[0002] Entering the 21st century, human demand for energy continues to rise, while fossil fuels on Earth are becoming increasingly scarce. At the same time, the development and utilization of energy generates large amounts of greenhouse gases and toxic substances, posing a significant threat to the ecological environment and human health. Against this backdrop, developing green, stable, and sustainable renewable energy storage systems has become a key direction for solving energy and environmental problems. Currently, lithium-ion batteries, with their high energy density, dominate in mobile devices and electric vehicles, making them one of the most successful energy storage systems. However, their large-scale application is severely limited by the risks posed by the toxicity, flammability, and explosiveness of the organic electrolytes used, as well as the scarcity and uneven distribution of lithium resources. In contrast, aqueous ammonium-ion batteries, using neutral aqueous solutions as electrolytes, offer advantages such as low cost and ease of preparation. Furthermore, the non-flammability and high specific heat capacity of water significantly reduce the probability of battery explosions and combustion, demonstrating greater safety and application potential in large-scale energy storage scenarios.
[0003] Electrode materials are a key factor determining the performance of aqueous batteries. Organic materials, due to their excellent designability and structural flexibility, have become high-performance electrode materials for aqueous ammonium-ion batteries. However, with the emergence of problems such as structural collapse, low capacity, and poor rate performance, the key to further improving the performance of organic electrode materials for aqueous ammonium-ion batteries lies in designing a conjugated organic electrode material with high capacity, excellent rate performance, and good stability.
[0004] Therefore, it is of great significance to design and develop conjugated organic electrode materials with high capacity, excellent rate performance, and good stability. Summary of the Invention
[0005] Purpose of the Invention: In order to solve the technical problems of low capacity and poor rate performance of existing aqueous ammonium ion battery electrode materials, the first objective of this invention is to provide a polynitro conjugated organic small molecule electrode material with excellent rate performance and cycle stability. The second objective of this invention is to provide a method for preparing the above-mentioned polynitro conjugated organic small molecule electrode material. The third objective of this invention is to provide applications of the above-mentioned polynitro conjugated organic small molecule electrode material.
[0006] Technical solution: The polynitro conjugated organic small molecule electrode material HATN-6NO2 of this invention has the following molecular structural formula:
[0007]
[0008] This invention adds nitro groups to the conjugated structure, increasing the number of nitro groups as active sites while ensuring structural stability. This gives the molecule multiple redox active sites, enabling more electron transfer and charge storage during charge and discharge, thus improving specific capacity. At the same time, its large π-conjugated system provides a stable structure, ensuring structural integrity and cycle stability during charge and discharge.
[0009] The preparation method of the polynitro conjugated organic small molecule electrode material of the present invention includes the following steps:
[0010] (1) In an inert atmosphere, 4,5-dibromophenyl-1,2-diamine and cyclohexanehexanone octahydrate were added to acetic acid and stirred thoroughly. Then, a dehydration condensation reaction was carried out to obtain a precursor mixture.
[0011] (2) Add the precursor mixture to ice water and add saturated sodium carbonate aqueous solution. Filter and wash thoroughly with N,N-dimethylformamide and acetone respectively. Freeze-dry the resulting filter cake to obtain the precursor.
[0012] (3) In an inert atmosphere, the precursor, 4-nitrophenylboronic acid, palladium catalyst and saturated potassium carbonate are mixed and added to N,N-dimethylformamide and water. After thorough mixing, the mixture is subjected to Suzuki coupling reaction to obtain a mixture.
[0013] (4) Pour the mixture into ice water, wash thoroughly with water, methanol and tetrahydrofuran respectively, filter, collect the filter cake and freeze dry to obtain the target product HATN-6NO2.
[0014] Further, in step (1), the mass ratio of 4,5-dibromophenyl-1,2-diamine and cyclohexanehexanone octahydrate is 50-52:17-20.
[0015] Furthermore, in step (1), the parameters for the dehydration condensation reaction are: reacting at 90–110°C for 70–72 h.
[0016] Furthermore, in step (2), the freeze-drying conditions are: freezing temperature of -70 to -90°C and freezing time of 7 to 8 hours.
[0017] Further, in step (3), the mass ratio of the precursor, 4-nitrophenylboronic acid, palladium catalyst and saturated potassium carbonate is 30-35:55-59:2-3:15-17; the palladium catalyst is tetrakis(triphenylphosphine)palladium; and the volume ratio of N,N-dimethylformamide and water is 3-3.5:1.
[0018] Furthermore, in step (3), the parameters of the Suzuki coupling reaction are: reaction at 120-140℃ for 60-72h.
[0019] Furthermore, in step (4), the freeze-drying temperature is -85℃ to -95℃, and the time is 6 to 8 hours. The purpose of the two drying processes is to eliminate residual moisture in the product, improve the drying quality, increase the purity of the product, and prevent structural collapse of the product during drying.
[0020] The application of the polynitro conjugated organic small molecule electrode material described in this invention in aqueous ammonium ion batteries.
[0021] Further, the application method is as follows: HATN-6NO2, a polynitro conjugated organic small molecule electrode material, conductive carbon material, and crosslinking agent are ground and mixed with an organic solvent to form a slurry. The slurry is then uniformly coated onto carbon paper or carbon cloth and vacuum dried to form an electrode sheet, which is the negative electrode of an aqueous ammonium ion battery. The mass ratio of HATN-6NO2, conductive carbon material, and crosslinking agent is 6-7:2-3:1.
[0022] Furthermore, the conductive carbon material is conductive carbon black Super P, the crosslinking agent is polyvinylidene fluoride, and the organic solvent is N-methylpyrrolidone; the vacuum drying conditions are: drying at 60-80°C for 8-12 hours.
[0023] Beneficial Effects: Compared with the prior art, the present invention has the following significant effects: The polynitro conjugated organic small molecule material in the present invention generates a precursor through dehydration condensation of cyclohexanehexanone and 4,5-dibromophenyl-1,2-diamine, which is then coupled with 4-nitrophenylboronic acid via a Suzuki coupling reaction to generate the final polynitro compound HATN-6NO2. The numerous redox active sites in the molecule provide the material with a large specific capacity, and both the C=N and -NO2 groups can store and coordinate NH4+. + This allows for greater electron transfer and charge storage, resulting in higher specific capacity in aqueous ammonium-ion batteries. Simultaneously, the large π-conjugated structure and high molecular weight of the polynitro compound HATN-6NO2 effectively increase molecular stability, preventing structural collapse and material dissolution. It also accelerates electron transfer and ion transport rates during charge and discharge, thus exhibiting strong rate performance and cycle stability. Attached Figure Description
[0024] Figure 1 This is a scanning electron microscope image of the polynitro conjugated organic small molecule electrode material prepared in Example 1;
[0025] Figure 2 To apply the polynitro conjugated organic small molecule electrode material in Example 1 in 2Ag-1 Charge-discharge curves at current density;
[0026] Figure 3 To apply the polynitro conjugated organic small molecule electrode material in Example 1 at 10Ag -1 Performance curves after 50,000 cycles at current density;
[0027] Figure 4 Linear cyclic voltammetry curves of the all-organic ammonium ion soft-pack battery using the polynitro conjugated organic small molecule electrode material in Example 1 at different scan rates;
[0028] Figure 5 This is a comparison chart of the rate of change of the polynitro conjugated organic small molecule electrode material in Application Example 1 and the electrode material in Comparative Example 1 at different current densities. Detailed Implementation
[0029] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings.
[0030] Example 1: The preparation method of the polynitro conjugated organic small molecule electrode material HATN-6NO2 described in this example includes the following steps:
[0031] (1) In an argon-filled glove box, 506 mg of 4,5-dibromophenyl-1,2-diamine and 189 mg of cyclohexanehexaone octahydrate were weighed and added to 100 ml of acetic acid. After stirring for 30 minutes to mix thoroughly, the mixture was heated to 100 °C and reacted for 72 h. The resulting mixture was added to ice water and saturated sodium carbonate aqueous solution. The mixture was filtered and washed three times with N,N-dimethylformamide and acetone respectively until the filtrate was colorless. The filter cake was collected and freeze-dried at -80 °C for 8 h to obtain the precursor.
[0032] (2) Weigh 318 mg of the precursor obtained in step (1) in an argon-filled glove box, mix it with 584 mg of 4-nitrophenylboronic acid, 26 mg of tetrakis(triphenylphosphine)palladium and 158 mg of saturated potassium carbonate, add it to a mixed solution of 120 ml N,N-dimethylformamide and 40 ml water, stir for 30 minutes to mix thoroughly, and then heat to 120 °C and react for 72 h. Pour the resulting mixture into ice water, wash and filter three times with water, methanol and tetrahydrofuran respectively until the filtrate is colorless, collect the filter cake and freeze dry at -90 °C for 8 h to obtain the structurally stable target product HATN-6NO2.
[0033] Figure 1The scanning electron microscope image of the polynitro compound HATN-6NO2 prepared in Example 1 shows that its surface has a rough structure and small particles, and some porous structure, which is conducive to the exposure of active sites, thereby improving the specific capacity and accelerating the electron transfer rate; the particles have a certain agglomeration structure, which is beneficial to the high conductivity of the electrode material.
[0034] Application Example 1: The polynitro conjugated organic small molecule electrode material HATN-6NO2, conductive carbon black super P, and polyvinylidene fluoride prepared in Example 1 were mixed with 1 ml of N-methylpyrrolidone at a mass ratio of 6:3:1 (masses of 60 mg, 30 mg, and 10 mg, respectively). The mixture was thoroughly ground in an agate mortar to ensure uniform mixing. The slurry was then coated onto carbon paper and vacuum dried at a stable temperature of 70°C for 12 h to obtain the working electrode (negative electrode).
[0035] Commercially available polyaniline, conductive carbon black Super P, and polyvinylidene fluoride were mixed with approximately 1 ml of N-methylpyrrolidone at a mass ratio of 6:3:1 (masses of 60 mg, 30 mg, and 10 mg, respectively). The mixture was then thoroughly ground in an agate mortar to ensure uniform mixing. The slurry was then coated onto carbon paper and vacuum-dried at a stable temperature of 70°C for 12 hours to obtain the electrode (positive electrode).
[0036] A pouch cell was assembled using an electrode made of HATN-6NO2 as the negative electrode and a commercially available polyaniline electrode as the positive electrode. A glass fiber membrane separated the two electrodes, and a 1M NH4Ac solution was used as the electrolyte. The test voltage range was 0–1.5V.
[0037] Figure 2 The electrode material HATN-6NO2 is in 2Ag -1 The charge-discharge curves at current density show that this organic material has a very high specific capacity, with a discharge capacity as high as 209 mAh g⁻¹. -1 .
[0038] Figure 3 The graph shows the long-cycle performance of HATN-6NO2 as an organic electrode material for ammonium-ion batteries. After 50,000 cycles, it still retains a high cycle retention rate of 80.1%, which shows that the electrode material exhibits excellent cycle stability.
[0039] Figure 4 The linear cyclic voltammetry curves of the pouch cell assembled in Example 1 show that the redox peaks are quite obvious at different scan rates, indicating good redox kinetics and promising application prospects.
[0040] Comparative Example 1: Unlike Example 1, this example uses a smaller molecular weight, fewer nitro groups, and smaller conjugated units, named HATN-3NO2, with the following structural formula:
[0041]
[0042] Its preparation method includes the following steps:
[0043] In an argon-filled glove box, 780 mg of cyclohexanehexanone octahydrate and 1150 mg of 3-nitro-1,2-phenylenediamine were weighed and dissolved in 150 ml of acetic acid solution. After stirring at room temperature for 30 minutes, the mixture was heated to 90 °C and reacted for 10 hours. After the reaction was completed, the mixture was cooled to room temperature. The suspension was filtered, and the filter cake was washed sequentially with hot acetic acid, acetone, water, and ethanol until the filtrate was colorless. The filter cake was collected and freeze-dried at -80 °C for 6 hours to obtain HATN-3NO2.
[0044] The HATN-3NO2, conductive carbon black super P, and polyvinylidene fluoride prepared in Comparative Example 1 were mixed with 1 ml of N-methylpyrrolidone in a mass ratio of 6:3:1 (masses of 60 mg, 30 mg, and 10 mg, respectively). The mixture was thoroughly ground in an agate mortar to ensure uniform mixing. The slurry was then coated onto carbon paper and vacuum dried at a stable temperature of 70 °C for 12 h to obtain the comparative working electrode.
[0045] Figure 5 It can be seen that HATN-6NO2 in Example 1 has excellent rate performance, with an initial 2Ag -1 A current density of 209 mAh g can be achieved. -1 The high specific capacity of HATN-3NO2 in Comparative Example 1, while HATN-3NO2 in Comparative Example 1 only showed a capacity of 114 mAh g. -1 Low specific capacity, at 20Ag -1 Even at high current densities, the discharge capacity of HATN-6NO2 remains as high as 79 mAh g. -1 It is much higher than the 26mAh g of HATN-3NO2. -1 Meanwhile, compared to HATN-3NO2 in Comparative Example 1, HATN-6NO2 in Example 1 exhibited better coulombic efficiency, approaching 100%, at all rate expansions.
Claims
1. A polynitro conjugated organic small molecule electrode material, characterized in that, The electrode material is HATN-6NO2, and its molecular structure is as follows:
2. A method for preparing the polynitro conjugated organic small molecule electrode material according to claim 1, characterized in that, Includes the following steps: (1) In an inert atmosphere, 4,5-dibromophenyl-1,2-diamine and cyclohexanehexanone octahydrate were added to acetic acid and stirred thoroughly. Then, a dehydration condensation reaction was carried out to obtain a precursor mixture. (2) Add the precursor mixture to ice water and add saturated sodium carbonate aqueous solution. Filter and wash thoroughly with N,N-dimethylformamide and acetone respectively. Freeze-dry the resulting filter cake to obtain the precursor. (3) In an inert atmosphere, the precursor, 4-nitrophenylboronic acid, palladium catalyst and saturated potassium carbonate are mixed and added to N,N-dimethylformamide and water. After thorough mixing, the mixture is subjected to Suzuki coupling reaction to obtain a mixture. (4) Pour the mixture into ice water, wash thoroughly with water, methanol and tetrahydrofuran respectively, filter, collect the filter cake and freeze dry to obtain the target product HATN-6NO2.
3. The preparation method according to claim 2, characterized in that, In step (1), the mass ratio of 4,5-dibromophenyl-1,2-diamine and cyclohexanehexanone octahydrate is 50-52:17-20.
4. The preparation method according to claim 2, characterized in that, In step (1), the parameters for the dehydration condensation reaction are: reacting at 90-110°C for 70-72 hours.
5. The preparation method according to claim 2, characterized in that, In step (2), the freeze-drying conditions are: freezing temperature of -70 to -90°C and freezing time of 7 to 8 hours.
6. The preparation method according to claim 2, characterized in that, In step (3), the mass ratio of the precursor, 4-nitrophenylboronic acid, palladium catalyst and saturated potassium carbonate is 30-35:55-59:2-3:15-17; the palladium catalyst is tetrakis(triphenylphosphine)palladium; and the volume ratio of N,N-dimethylformamide and water is 3-4:
1.
7. The preparation method according to claim 2, characterized in that, In step (3), the parameters for the Suzuki coupling reaction are: reaction at 120-140℃ for 60-72h.
8. The preparation method according to claim 2, characterized in that, In step (4), the freeze-drying temperature is -85℃ to -95℃ and the time is 6 to 8 hours.
9. The application of the polynitro conjugated organic small molecule electrode material according to claim 1 in an aqueous ammonium ion battery.
10. The application according to claim 9, characterized in that, The application method is as follows: the polynitro conjugated organic small molecule electrode material HATN-6NO2, conductive carbon material, and crosslinking agent described in claim 1 are ground and mixed with an organic solvent to form a slurry. The slurry is uniformly coated on carbon paper or carbon cloth and vacuum dried to form an electrode sheet, which is the negative electrode of an aqueous ammonium ion battery. The mass ratio of the polynitro conjugated organic small molecule electrode material HATN-6NO2, conductive carbon material, and crosslinking agent is 6-7:2-3:1.