Application of pure organic two-dimensional molecular woven polymer material

Abstract

The invention discloses an application of a pure organic two-dimensional molecular woven polymer material in an ASEI coating and a battery. Pure organic two-dimensional molecular woven polymer material with function of inhibiting growth of lithium dendrites, and is formed by weaving polymer molecular chains as shown in the specification in a two-up two-down interspersed manner: # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the field of materials science, and in particular to the application of a pure organic two-dimensional molecular braided polymer material in artificial solid electrolyte interface (ASEI) coatings and batteries. Background Art

[0002] Since graphene was first synthesized by mechanical exfoliation in 2004, two-dimensional materials have attracted widespread attention. Their ultrathin sheet structure and extremely high surface area offer superior properties and a wealth of applications, including enormous potential in fields such as condensed matter physics, materials science, and chemistry.

[0003] Currently, research on two-dimensional materials is limited to inorganic materials such as graphene, disulfides, selenides, and nitrides. The preparation of purely organic two-dimensional materials remains a challenge in this area. Compared to inorganic materials, the structure of organic two-dimensional materials can be precisely regulated through synthetic methods, enabling diverse chemical functionalities. This tunability allows organic two-dimensional materials to be designed with specific properties and functions, making them suitable for diverse applications.

[0004] For example, patent publication number CN109134853A discloses a method for preparing two-dimensional organic materials. Using aromatic amino compounds with similar symmetrical structures, such as 1,3,5-triaminobenzene, as monomer molecules, a two-dimensional polymer is prepared through an amino coupling reaction on the surface of two-dimensional cuprous chloride nanocrystals, which serve as templates and catalysts. This method has broad applications in organic dyes, biopharmaceuticals, food additives, free radical inducing agents, liquid crystal materials, and nonlinear optical materials.

[0005] For example, the patent specification with publication number CN109134854A discloses a method for preparing a two-dimensional organic material with adjustable pore size. Monomer molecules such as 1,3,5-triaminobenzene and 1,4-dibromobenzene are selected to prepare a two-dimensional polymer on the surface of a two-dimensional cuprous chloride nanocrystal material that acts as a template and catalyst.

[0006] Emerging molecular braiding technologies enable the production of thin layers of two-dimensional molecularly braided polymers. The orderly interlacing of polymer segments imparts excellent mechanical properties and uniform porosity at the molecular scale. Furthermore, the polymer structure is easily modifiable, allowing functional sites to be uniformly introduced into the molecularly braided polymer as needed. Consequently, two-dimensional molecularly braided polymer crystals can integrate a variety of specialized properties, making them ideal single-component artificial solid electrolyte interface coatings. Summary of the Invention

[0007] We previously reported the preparation of a class of pure organic two-dimensional molecular braided polymer networks (WPNs) (Nat. Chem. 16, 1906-1914 (2024)). Here, we use their crystals as a new ASEI material for lithium metal anodes. The ASEI coating constructed from WPN has excellent mechanical strength, toughness, lithium ion conductivity, nanoscale thickness, and electronic insulation. The results show that the WPN@Li / / LFP full battery has a high performance at 1C (1C = 170mAg -2 ) current, exhibiting a high capacity retention of 97% after 270 cycles, which is better than the previously reported 2D polymer material-enhanced full-battery performance.

[0008] The specific technical solutions are as follows:

[0009] In a first aspect, the present invention provides an application of a pure organic two-dimensional molecular braided polymer material in an ASEI coating, wherein the pure organic two-dimensional molecular braided polymer material is formed by braiding polymer molecular chains as shown below in a two-up and two-down interlaced manner:

[0010]

[0011] The application of the pure organic two-dimensional molecular woven polymer material in ASEI coating, the pure organic two-dimensional molecular woven polymer material can be used to prepare ASEI coating modified on the surface of lithium metal electrode or copper metal electrode.

[0012] The application of the pure organic two-dimensional molecular woven polymer material in the ASEI coating can be used to modify the surface of the negative electrode of a battery. Furthermore, the battery can be a lithium battery.

[0013] In a second aspect, the present invention provides an application of a pure organic two-dimensional molecular woven polymer material in a battery, wherein the pure organic two-dimensional molecular woven polymer material is formed by weaving polymer molecular chains as shown below in a two-up and two-down interlaced manner:

[0014]

[0015] The application of the pure organic two-dimensional molecular woven polymer material in batteries, the pure organic two-dimensional molecular woven polymer material can be used in lithium batteries.

[0016] The pure organic two-dimensional molecular woven polymer material is used in batteries. The pure organic two-dimensional molecular woven polymer material can be used to prepare ASEI coating.

[0017] The application of the pure organic two-dimensional molecular woven polymer material in batteries, the pure organic two-dimensional molecular woven polymer material can be used to prepare an ASEI coating modified on the surface of a lithium metal electrode or a copper metal electrode.

[0018] The pure organic two-dimensional molecular woven polymer material is used in batteries, and the ASEI coating can be used to modify the surface of the battery negative electrode.

[0019] In a third aspect, the present invention provides a lithium metal electrode, comprising metallic lithium and an ASEI coating modified on the surface of the metallic lithium;

[0020] The raw material composition of the ASEI coating includes pure organic two-dimensional molecular woven polymer material;

[0021] The pure organic two-dimensional molecular braided polymer material is formed by weaving the polymer molecular chains shown below in a two-up and two-down interlacing manner:

[0022]

[0023] In a fourth aspect, the present invention provides a battery comprising the lithium metal electrode described in the third aspect.

[0024] The battery described in the fourth aspect can be a lithium battery

[0025] In the battery described in the fourth aspect, the lithium metal electrode can be the negative electrode of the battery.

[0026] The pure organic two-dimensional molecular woven polymer material of the present invention has a clear single crystal structure, wherein the molecular chain is formed by monomers 2,2′-(1,4-phenyl)bis[1,3,2-benzodioxaborolane] and 1,2-trans-bis(4-pyridyl)ethylene through the coordination of boron atoms and nitrogen atoms.

[0027] The pure organic two-dimensional molecular woven polymer material used in the present invention is an existing material previously reported by the inventors, and details can be found in the document Nat. Chem. 16, 1906-1914 (2024).

[0028] Here, the present invention provides an exemplary preparation method of the pure organic two-dimensional molecular woven polymer material, comprising the steps of:

[0029] (1) 1,4-terephthalenediboronic acid and catechol are added to a mixture of toluene and methanol, and the mixture is stirred at 110° C. under nitrogen atmosphere. Water produced during the reaction is removed using a water separator. After the reaction is completed, the solvent is dried and the resulting solid is placed in a round-bottom flask. The impurity catechol in the product is removed using a sublimator to obtain a pure solid product 2,2′-(1,4-phenyl)bis[1,3,2-benzodioxaborolane];

[0030] (2) dispersing the 2,2′-(1,4-phenyl)bis[1,3,2-benzodioxaborolane] and 1,2-trans-bis(4-pyridyl)ethylene obtained in step (1) in a solvent, ultrasonicating the mixture in a water bath for 15 minutes, keeping the mixture at 90° C. for reaction, slowly cooling the mixture to room temperature, and filtering the mixture to obtain a sheet-like two-dimensional molecularly woven polymer single crystal;

[0031] (3) using a micromechanical exfoliation method to exfoliate the sheet-like two-dimensional molecularly woven polymer single crystal obtained in step (2) to obtain a single-layer, double-layer, triple-layer or other two-dimensional molecularly woven polymer nanosheet; and / or,

[0032] The sheet-like two-dimensional molecularly woven polymer single crystal obtained in step (2) was dispersed in a solvent and subjected to ultrasonic exfoliation for 30 minutes.

[0033] The molar ratio of the 1,4-terephthalenediboronic acid to the catechol in step (1) may be 1:(2.1-3.0).

[0034] The volume ratio of toluene to methanol in the mixed solution described in step (1) can be 10:1.

[0035] The solvent described in step (2) can be toluene, benzene, p-xylene, etc.

[0036] The heat preservation reaction time in step (2) can be 5 to 10 hours.

[0037] The cooling time in step (2) can be 2 to 10 hours.

[0038] The solvent described in step (3) can be n-hexane, cyclohexane, benzene, toluene, etc.

[0039] The exemplary preparation method of the above-mentioned pure organic two-dimensional molecular woven polymer material is simple to operate, reliable in route and low in cost.

[0040] The pure organic woven polymer material of the present invention can be exfoliated into single-layer, double-layer, and triple-layer nanosheets through micromechanical exfoliation and liquid-phase exfoliation. The exfoliated pure organic molecular woven polymer nanosheets can be characterized by Raman spectroscopy and atomic force microscopy. Atomic force microscopy measurements show that the thickness of a single layer of pure organic woven polymer can reach 1.3 nanometers.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The pure organic two-dimensional molecular braided polymer material of the present invention has the function of inhibiting the growth of lithium dendrites and can be used for ASEI coatings and batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1These are photos, scanning electron microscope (SEM) images, and atomic force microscope (AFM) images of the pure organic two-dimensional molecular woven polymer WPN-1 of Example 1.

[0044] Figure 2 This is the crystal structure diagram of the pure organic two-dimensional molecular braided polymer WPN-1 in Example 1.

[0045] Figure 3 This is the crystal structure diagram of the pure organic two-dimensional molecular braided polymer WPN-2 in Example 2.

[0046] Figure 4 This is the crystal structure diagram of the pure organic two-dimensional molecular braided polymer WPN-3 in Example 3.

[0047] Figure 5 These are the single-layer, double-layer and triple-layer nanosheets obtained after peeling off WPN-1, as well as their Raman spectra and Raman imaging images.

[0048] Figure 6 5mAcm -2 Figure 3. Lithium death time test results of pure lithium (Bare Li) and symmetric lithium / lithium batteries with pure organic two-dimensional woven polymer ASEI layer (WPN@Li or WP-1@Li) under current density.

[0049] Figure 7 The results show that the symmetrical lithium / lithium battery with pure lithium (Bare Li) and pure organic two-dimensional woven polymer ASEI layer (WPN@Li or WP-1@Li) has a high conductivity at 5 mA cm -2 、1mAh cm -2 Constant current charge and discharge curve diagram.

[0050] Figure 8 At a current density of 0.5 mA cm -2 , surface capacity is 0.5mAh cm -2 Figure 3 shows the cycling stability test results of pure copper (Bare Cu) and WPN@Cu (or WP-1@Li) in half-cells under the conditions of .

[0051] Figure 9 The negative electrode capacity is 10 mAh cm -2 , the positive electrode (lithium iron phosphate) capacity is 3mAh cm -2 , the current density is 1C (1C=170mAg -2 )’s full battery long-term cycling test results of Li / / LFP (labeled Bare Li / / LFP) and WPN@Li / / LFP (labeled WP-1@Li / / LFP).

[0052] Figure 10The full-cell rate performance test results of Li / / LFP (labeled Bare Li / / LFP) and WPN@Li / / LFP (labeled WP-1@Li / / LFP), blue: Li / / LFP, red: WPN@Li / / LFP. DETAILED DESCRIPTION

[0053] The present invention will be further described below with reference to the accompanying drawings and specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0054] In the following examples, the operating methods without specifying specific conditions are generally carried out under conventional conditions or conditions recommended by the manufacturer.

[0055] Example 1:

[0056] Preparation method of pure organic two-dimensional molecular braided polymer material WPN-1 (or WP-1):

[0057] 15.0 mg of 2,2′-(1,4-phenyl)bis[1,3,2-benzodioxaborolane] was weighed into a 20 mL reactor liner, followed by 8.7 mg of 1,2-trans-bis(4-pyridyl)ethylene and 15 mL of toluene. The mixture was ultrasonicated in a water bath for 15 minutes and then maintained at 90°C. After the reaction, the mixture was slowly cooled to room temperature and filtered to yield the red, pure organic molecular braided polymer WPN-1 (22.1 mg, 93% yield). Figure 1 These are photos, scanning electron microscope (SEM) images, and atomic force microscope (AFM) images of the pure organic two-dimensional molecular woven polymer WPN-1 of Example 1. Figure 2 This is the crystal structure diagram of the pure organic two-dimensional molecular braided polymer WPN-1 in Example 1.

[0058] Example 2:

[0059] Preparation method of pure organic two-dimensional molecular braided polymer material WPN-2:

[0060] 15.0 mg of 2,2′-(1,4-phenyl)bis[1,3,2-benzodioxaborolane] was weighed into a 20 mL reactor liner, followed by 8.7 mg of 1,2-trans-bis(4-pyridyl)ethylene and 15 mL of p-xylene. The mixture was ultrasonicated in a water bath for 15 minutes and then maintained at 90°C. After the reaction, the temperature was slowly cooled to room temperature, and the reaction solution was filtered to obtain the red, pure organic molecular braided polymer WPN-2 (22.5 mg, 95% yield). Figure 3 This is the crystal structure diagram of the pure organic two-dimensional molecular braided polymer WPN-2 in Example 2.

[0061] Example 3:

[0062] Preparation method of pure organic two-dimensional molecular braided polymer material WPN-3:

[0063] 15.0 mg of 2,2′-(1,4-phenyl)bis[1,3,2-benzodioxaborolane] was weighed into a 20 mL reactor liner, followed by 8.7 mg of 1,2-trans-bis(4-pyridyl)ethylene and 15 mL of benzene. The mixture was ultrasonicated in a water bath for 15 minutes and then maintained at 90°C. After the reaction, the temperature was slowly cooled to room temperature, and the reaction solution was filtered to obtain the red, pure organic molecular braided polymer WPN-3 (21.3 mg, 90% yield). Figure 4 This is the crystal structure diagram of the pure organic two-dimensional molecular braided polymer WPN-3 in Example 3.

[0064] Figure 5 These are the single-layer, double-layer and triple-layer nanosheets obtained after peeling off WPN-1, as well as their Raman spectra and Raman imaging images.

[0065] Figure 6 5mAcm -2 Figure 2 shows the lithium death time test results for pure lithium (bare Li) and symmetric lithium / lithium batteries with a pure organic two-dimensional woven polymer ASEI layer at different current densities. The coating is prepared by preparing a 1 mg / mL suspension of WPN-1 in n-hexane and then evenly spraying it onto the surface of a 12 mm diameter Li sheet to form WPN@Li, or WP-1@Li. Test results show that the pure lithium anode short-circuited after only 12.5 hours of operation at this current density, while the WPN@Li maintained stable operation for nearly 38 hours. SEM images show that pure lithium generates a large number of lithium dendrites, while the WPN@Li has a smooth surface, which effectively suppresses lithium dendrites.

[0066] Figure 7 The results show that the symmetrical lithium / lithium battery with pure lithium (Bare Li) and pure organic two-dimensional woven polymer ASEI layer (WPN@Li or WP-1@Li) has a high conductivity at 5 mA cm -2 、1mAh cm -2 The constant current charge and discharge curves at 100 nm are shown. Test results show that pure lithium can operate stably for less than 300 h, while WPN@Li can operate stably for more than 1600 h, showing better cycle stability.

[0067] Figure 8 At a current density of 0.5 mA cm -2 , surface capacity is 0.5mAh cm -2Figure 3 shows the cycling stability test results of pure copper (Bare Cu) and WPN@Cu (or WP-1@Li) in a half-cell under 20°C conditions. The preparation of WPN@Cu is similar to that of WPN@Li: WPN-1 is first prepared into a 1 mg / mL suspension in n-hexane and then evenly sprayed onto the surface of a 12 mm diameter Cu sheet to form WPN@Cu. The test results show that the coulombic efficiency of pure copper drops sharply after 120 hours of operation, while WPN@Cu maintains a coulombic efficiency close to 100% after 400 hours of operation, demonstrating better long-term cycling stability.

[0068] Figure 9 The negative electrode capacity is 10 mAh cm -2 The positive electrode lithium iron phosphate (LFP) capacity is 3 mAh cm -2 , the current density is 1C (1C=170mAg -2 Long-term cycling test results for full-cell Li / / LFP (labeled Bare Li / / LFP) and WPN@Li / / LFP (labeled WP-1@Li / / LFP). Bare Li / / LFP refers to a full-cell with bare lithium as the anode and lithium iron phosphate as the cathode; WPN@Li / / LFP refers to a full-cell with WPN@Li as the anode and lithium iron phosphate as the cathode. The test results show that the battery capacity and coulombic efficiency of Li / / LFP begin to drop sharply after nearly 100 hours of operation, while WPN@Li / / LFP still maintains 97% of the battery capacity and nearly 100% coulombic efficiency after 270 hours of operation.

[0069] Figure 10 Figure 2 shows the full-cell rate performance test results for Li / / LFP (labeled Bare Li / / LFP) and WPN@Li / / LFP (labeled WP-1@Li / / LFP). Blue: Li / / LFP, red: WPN@Li / / LFP. At different current densities, WPN@Li / / LFP has higher cell capacity and therefore better rate performance.

[0070] In addition, it should be understood that after reading the above description of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. Application of a pure organic two-dimensional molecular braided polymer material in ASEI coating, characterized in that: The pure organic two-dimensional molecular braided polymer material is formed by weaving the polymer molecular chains shown below in a two-up and two-down interlacing manner:

2. The use of the pure organic two-dimensional molecular braided polymer material in ASEI coating according to claim 1, characterized in that: The pure organic two-dimensional molecular braided polymer material is used to prepare an ASEI coating modified on the surface of a lithium metal electrode or a copper metal electrode.

3. The use of the pure organic two-dimensional molecular braided polymer material in ASEI coating according to claim 1 or 2, characterized in that: The ASEI coating is used to modify the surface of the battery negative electrode.

4. Application of a pure organic two-dimensional molecular woven polymer material in a battery, characterized in that: The pure organic two-dimensional molecular braided polymer material is formed by weaving the polymer molecular chains shown below in a two-up and two-down interlacing manner:

5. The use of the pure organic two-dimensional molecular woven polymer material in a battery according to claim 4, characterized in that: The pure organic two-dimensional molecular braided polymer material is used to prepare an ASEI coating.

6. The use of the pure organic two-dimensional molecular woven polymer material in a battery according to claim 5, characterized in that: The pure organic two-dimensional molecular braided polymer material is used to prepare an ASEI coating modified on the surface of a lithium metal electrode or a copper metal electrode.

7. Use of the pure organic two-dimensional molecular woven polymer material in a battery according to claim 5 or 6, characterized in that: The ASEI coating is used to modify the surface of the battery negative electrode.

8. A lithium metal electrode, characterized in that It includes metallic lithium and an ASEI coating modified on the surface of the metallic lithium; The raw material composition of the ASEI coating includes pure organic two-dimensional molecular woven polymer material; The pure organic two-dimensional molecular braided polymer material is formed by weaving the polymer molecular chains shown below in a two-up and two-down interlacing manner:

9. A battery, characterized in that: Comprising the lithium metal electrode according to claim 8.

10. The battery according to claim 9, characterized in that The lithium metal electrode is the negative electrode of the battery.

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