A supramolecular organic superstructure material and its preparation method and application

Abstract

The present invention provides a method for preparing a supramolecular organic superstructure material, comprising the following steps: step S1, dissolving cyanuric acid and 1,3,5-triazine-2,4,6-triamine in methyl sulfoxide and N-methyl pyrrolidone and mixing them evenly to obtain a mixed solution; step S2, stirring the mixed solution, reacting at a preset temperature and a preset time, filtering, washing, and drying after the reaction is completed to obtain a supramolecular organic superstructure material, wherein, in step S1, the mass ratio of cyanuric acid: 1,3,5-triazine-2,4,6-triamine: dimethyl sulfoxide: N-methyl pyrrolidone is 1: 0.9-1.2: 50-100: 5-10. The present invention also provides a supramolecular organic superstructure material, which is prepared by the preparation method of the supramolecular organic superstructure material. The present invention also provides an application of the supramolecular organic superstructure material in an aqueous zinc-organic battery.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation, and in particular relates to a supramolecular organic superstructure material and a preparation method and application thereof. Background Art

[0002] In order to meet environmental and sustainability challenges, it is of great significance to develop green and efficient advanced battery materials. Among many energy storage devices, aqueous zinc-organic battery is a new type of "green battery" composed of zinc metal anode, organic material cathode and zinc-containing aqueous electrolyte. It has the advantages of low cost, simple manufacturing process, good safety and abundant zinc resources. It has broad application prospects in emerging electronic smart devices and other fields. Given the inherent theoretical specific capacity of zinc anode (820mAh g -1 ) and a lower redox voltage of (-0.76 V vs. standard hydrogen electrode). The performance of aqueous zinc-organic batteries is mainly determined by the organic cathode material, and energy storage is achieved based on the reversible redox reaction between the active groups of the organic material and the electrolyte ions.

[0003] Among them, organic active materials are composed of carbon, hydrogen, oxygen and nitrogen, which are abundant in nature and light in weight. They are considered to be zinc-organic battery cathode materials with great development prospects due to their structural and functional diversity, environmental protection and cheap abundance. By adjusting the active functional groups on the skeleton of aromatic organic materials, their electrochemical activity and redox kinetics can be systematically regulated to improve the battery energy storage performance. Light molecular weight organic small molecules are often used as organic cathode materials due to their high redox activity. However, organic small molecule materials have poor intrinsic conductivity, which limits their reaction kinetics and charge storage rate, and have high solubility in electrolytes, resulting in the loss of active substances in organic materials during the cycle, causing a sharp attenuation of electrode activity and insufficient battery cycle stability. The assembly of organic small molecule basic units through polymerization or non-covalent bonds to form high molecular weight organic matter can inhibit the dissolution of the material in the electrolyte. At the same time, the conjugated aromatic structure of the organic matter is conducive to electronic conduction, giving the battery a longer cycle life. However, the disordered stacking structure of polymers usually causes hysteresis in the kinetics of ion transport, which is not conducive to the accumulation of charge at the electrode / electrolyte interface, resulting in the inability to fully utilize the active sites of organic materials, which is not conducive to the performance of battery capacity. Therefore, it is urgent to develop organic cathode materials with both high redox activity and structural stability to further improve the battery specific capacity and cycle life. Summary of the invention

[0004] The present invention is made to solve the above problems, and aims to provide a supramolecular organic superstructure material and a preparation method and application thereof.

[0005] The present invention provides a method for preparing a supramolecular organic superstructure material, which has the following characteristics and comprises the following steps: step S1, dissolving cyanuric acid and 1,3,5-triazine-2,4,6-triamine in methyl sulfoxide and N-methylpyrrolidone and mixing them evenly to obtain a mixed solution;

[0006] Step S2, stirring the mixed solution, reacting at a preset temperature and a preset time, filtering, washing, and drying after the reaction is completed to obtain a supramolecular organic superstructure material,

[0007] Wherein, in step S1, the mass ratio of cyanuric acid: 1,3,5-triazine-2,4,6-triamine: dimethyl sulfoxide: N-methylpyrrolidone is 1: 0.9-1.2: 50-100: 5-10.

[0008] The method for preparing the supramolecular organic superstructure material provided by the present invention may also have the following feature: wherein, in step S2, when the mixed solution is stirred, the stirring speed is 300 rpm to 800 rpm.

[0009] The method for preparing the supramolecular organic superstructure material provided by the present invention may also have the following characteristics: wherein, in step S2, the preset temperature is 20° C. to 50° C., and the preset time is 5 min to 10 min.

[0010] The method for preparing the supramolecular organic superstructure material provided by the present invention may also have the following feature: wherein, in step S2, ethanol is used for washing.

[0011] The present invention also provides a supramolecular organic superstructure material, which has the following characteristics: it is prepared by the above-mentioned method for preparing the supramolecular organic superstructure material.

[0012] The present invention also provides an application of the supramolecular organic superstructure material in an aqueous zinc-organic battery.

[0013] Functions and Effects of the Invention

[0014] According to a method for preparing a supramolecular organic superstructure material involved in the present invention, cyanuric acid and 1,3,5-triazine-2,4,6-triamine are selected as building blocks, and the two are reacted in a mixed solvent of dimethyl sulfoxide and N-methylpyrrolidone through hydrogen bonding and π-π stacking to prepare a supramolecular organic superstructure material.

[0015] The supramolecular organic superstructure material prepared by the present invention has a three-dimensional open flower-like microstructure, which can provide more exposed carbonyl active sites and convenient ion diffusion pathways, and has excellent electronic conductivity and mechanical strength, which improves the electron transmission efficiency and can inhibit its dissolution in the electrolyte; and, compared with conventional organic materials for storing Zn 2+The ion mechanism is different. The hydrogen bond network connected in the supramolecular organic superstructure material of the present invention can overcome the high reaction energy barrier to solvate Zn 2+ The slow interfacial charge transfer caused by ions can effectively reduce the energy barrier of proton charge transfer and promote the H + Ions migrate rapidly through the Grotthuss mechanism, achieving full utilization of electroactive carbonyl sites, which is beneficial to significantly improve the battery's charge storage performance.

[0016] Therefore, the supramolecular organic superstructure material prepared by the preparation method of the present invention has the advantages of exquisite surface structure, rich electroactive sites, high skeleton stability and developed internal pores, which can effectively solve the problems of low conductivity and high solubility of organic materials and insufficient utilization of active sites, thereby improving the electrochemical properties of electrode materials such as specific capacity, rate performance and cycle life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a scanning electron microscope image of the supramolecular organic superstructure material in Example 1 of the present invention;

[0018] Figure 2 is a transmission electron microscope image of the supramolecular organic superstructure material in Example 1 of the present invention;

[0019] Figure 3 is the structural formula of the supramolecular organic superstructure material in Example 1 of the present invention;

[0020] Figure 4 is the energy band gap of the supramolecular organic superstructure material in the first embodiment of the present invention;

[0021] Figure 5 is an ultraviolet-visible absorption spectrum of the supramolecular organic superstructure material in Example 1 of the present invention measured in an aqueous electrolyte;

[0022] Figure 6 is a rate performance diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material in Example 1 of the present invention;

[0023] Figure 7 is a cycle stability diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material at a current density of 10 A / g in Example 1 of the present invention;

[0024] Figure 8 is a scanning electron microscope image of the supramolecular organic superstructure material in Example 2 of the present invention;

[0025] Fig. 9This is a rate performance diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material in Example 2 of the present invention.

[0026] Fig.10 is a scanning electron microscope image of the supramolecular organic superstructure material in Example 3 of the present invention;

[0027] Fig.11 This is a rate performance diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material in Example 3 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the following examples are combined with the accompanying drawings to specifically describe the supramolecular organic superstructure material and its preparation method and application of the present invention.

[0029] <Example 1>

[0030] The method for preparing the supramolecular organic superstructure material of this embodiment comprises the following steps:

[0031] Step S1, weighing cyanuric acid, 1,3,5-triazine-2,4,6-triamine, dimethyl sulfoxide and N-methylpyrrolidone in a mass ratio of 1:1.1:80:8, dissolving cyanuric acid and 1,3,5-triazine-2,4,6-triamine in methyl sulfoxide and N-methylpyrrolidone and mixing them evenly to obtain a mixed solution;

[0032] Step S2, stirring the mixed solution at a stirring speed of 500 rpm, reacting at 25° C. for 5 minutes, filtering, washing with ethanol, and drying after the reaction is completed to obtain a supramolecular organic superstructure material.

[0033] The structure of the supramolecular organic superstructure material prepared in this example was characterized. Figure 1 is a scanning electron microscope image of the supramolecular organic superstructure material in Example 1 of the present invention, Figure 2 This is a transmission electron microscope image of the supramolecular organic superstructure material in Example 1 of the present invention.

[0034] like Figure 1 and Figure 2 As shown, the supramolecular organic superstructure material prepared in this embodiment is assembled into a flower-like structure by nanosheet basic units.

[0035] Figure 3 is the structural formula of the supramolecular organic superstructure material in the first embodiment of the present invention.

[0036] like Figure 3As shown, the -NH2 group of the melamine molecule is bonded to the C=O group of the 1,3,5-triazine-2,4,6-triamine molecule in the form of NH...O hydrogen bonds, and at the same time, the -NH group of each 1,3,5-triazine-2,4,6-triamine molecule is bonded to the C=N group of the melamine molecule in the form of NH...N hydrogen bonds, thereby forming a two-dimensional supramolecular structure, which forms a supramolecular organic superstructure material through inter-plane π-π stacking.

[0037] Figure 4 is the energy band gap of the supramolecular organic superstructure material in the first embodiment of the present invention.

[0038] like Figure 4 As shown, the supramolecular organic superstructure material prepared in this embodiment has an ultra-low energy band gap of 2.08 eV, which is much lower than most organic electrode materials, indicating that the superstructure material has high electrical conductivity, which is conducive to better charge transfer efficiency and lower kinetic hindrance to promote redox reactions.

[0039] Figure 5 This is a UV-visible absorption spectrum of the supramolecular organic superstructure material in Example 1 of the present invention measured in an aqueous electrolyte.

[0040] like Figure 5 As shown, after the ultraviolet-visible absorption spectrum test of the electrolyte in which the supramolecular organic superstructure material was immersed, no obvious absorption peak signal was observed, indicating that the structure of the organic superstructure material is quite stable during the electrochemical reaction and is insoluble in the electrolyte. The anti-dissolution property of the supramolecular organic superstructure material of this embodiment mainly comes from its stable three-dimensional superstructure.

[0041] In this embodiment, the prepared supramolecular organic superstructure material is also used as an electrode material to prepare an aqueous zinc-organic battery. The specific preparation process is as follows:

[0042] Supramolecular organic superstructure material, 60wt% polytetrafluoroethylene emulsion (purchased from Shanghai San Ai Fu New Materials Co., Ltd.), and graphite were weighed in a mass ratio of 6:3.5:0.5. After the above materials were mixed evenly, they were placed in an oven for drying. The dried sample was pressed onto a stainless steel mesh at a pressure of 20MPa and vacuum dried at 60℃ for 24h to make an electrode sheet. A CR2032 button battery shell was selected, and the prepared working electrode was used as the positive electrode, a metal zinc sheet (purity ≥99.99%) was used as the negative electrode, and a GE-Whatman glass fiber diaphragm was used. 3mol / L

[0043] The Zn(SO3CF3)2 solution was used as the electrolyte to assemble an aqueous zinc-organic battery.

[0044] 0 The aqueous zinc-organic

[0045] The energy storage performance of the battery was tested, and the test results are as follows:

[0046] Figure 6 This is a rate performance diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material in Example 1 of the present invention.

[0047] like Figure 6 As shown, the aqueous zinc-organic battery prepared by using the supramolecular organic superstructure material of this embodiment as the electrode material has a specific capacity of more than 300 mAh / g and an energy density of more than 250 Wh / kg at a current density of 1 A / g; at a current density of 150 A / g, its specific capacity is more than 130 mAh / g and its energy density is more than 100 Wh / kg, indicating that the supramolecular organic superstructure material has high specific capacity, rate performance and energy density as a cathode material of an aqueous zinc-organic battery.

[0048] 0 Figure 7 This is a cycle stability diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material at a current density of 10 A / g in Example 1 of the present invention.

[0049] like Figure 7 As shown, after 50,000 cycles of charge and discharge, the capacity retention rate of the prepared aqueous zinc-organic battery is above 90%, indicating that the supramolecular organic superstructure material has significant cycle stability.

[0050] <Example 2>

[0051] The method for preparing the supramolecular organic superstructure material of this embodiment comprises the following steps:

[0052] Step S1, weighing cyanuric acid, 1,3,5-triazine-2,4,6-triamine, dimethyl sulfoxide and N-methylpyrrolidone in a mass ratio of 1:1.1:90:8, dissolving cyanuric acid and 1,3,5-triazine-2,4,6-triamine in methyl sulfoxide and N-methylpyrrolidone and mixing them evenly to obtain a mixed solution;

[0053] Step S2, stirring the mixed solution at a stirring speed of 300 rpm, reacting at 30° C. for 10 min, filtering, washing with ethanol, and drying after the reaction is completed to obtain a supramolecular organic superstructure material.

[0054] The structure of the supramolecular organic superstructure material prepared in this example was characterized. Figure 8 This is a scanning electron microscope image of the supramolecular organic superstructure material in Example 2 of the present invention.

[0055] like Figure 8 As shown, the supramolecular organic superstructure material prepared in this embodiment is assembled into a flower-like structure by nanosheet basic units.

[0056] The structural formula of the supramolecular organic superstructure material in the embodiment of the present invention is the same as that in the first embodiment.

[0057] In this embodiment, the prepared supramolecular organic superstructure material is also used as an electrode material to prepare an aqueous zinc-organic battery, and the specific preparation process is the same as that of the first embodiment.

[0058] The energy storage performance of the aqueous zinc-organic battery prepared in this example was tested using a CT3001A blue battery test system. The test results are as follows:

[0059] Fig. 9 This is a rate performance diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material in Example 2 of the present invention.

[0060] like Fig. 9 As shown, the aqueous zinc-organic battery prepared by using the supramolecular organic superstructure material of this embodiment as the electrode material has a specific capacity of more than 290 mAh / g and an energy density of more than 210 Wh / kg at a current density of 1 A / g; at a current density of 150 A / g, its specific capacity is more than 120 mAh / g and its energy density is more than 80 Wh / kg, indicating that the supramolecular organic superstructure material has high specific capacity, rate performance and energy density as a cathode material for aqueous zinc-organic batteries.

[0061] <Example 3>

[0062] The method for preparing the supramolecular organic superstructure material of this embodiment comprises the following steps:

[0063] Step S1, weighing cyanuric acid, 1,3,5-triazine-2,4,6-triamine, dimethyl sulfoxide and N-methylpyrrolidone in a mass ratio of 1:1.1:100:5, dissolving cyanuric acid and 1,3,5-triazine-2,4,6-triamine in methyl sulfoxide and N-methylpyrrolidone and mixing them evenly to obtain a mixed solution;

[0064] Step S2, stirring the mixed solution at a stirring speed of 500 rpm, reacting at 20° C. for 5 minutes, filtering, washing with ethanol, and drying after the reaction is completed to obtain a supramolecular organic superstructure material.

[0065] The structure of the supramolecular organic superstructure material prepared in this example was characterized. Fig.10 This is a scanning electron microscope image of the supramolecular organic superstructure material in Example 3 of the present invention.

[0066] like Fig.10 As shown, the supramolecular organic superstructure material prepared in this embodiment is assembled into a flower-like structure by nanosheet basic units.

[0067] The structural formula of the supramolecular organic superstructure material in the embodiment of the present invention is the same as that in the first embodiment.

[0068] In this embodiment, the prepared supramolecular organic superstructure material is also used as an electrode material to prepare an aqueous zinc-organic battery, and the specific preparation process is the same as that of the first embodiment.

[0069] The energy storage performance of the aqueous zinc-organic battery prepared in this example was tested using a CT3001A blue battery test system. The test results are as follows:

[0070] Fig.11 This is a rate performance diagram of an aqueous zinc-organic battery prepared using the supramolecular organic superstructure material as a cathode material in Example 3 of the present invention.

[0071] like Fig.11 As shown, the aqueous zinc-organic battery prepared by using the supramolecular organic superstructure material of this embodiment as the electrode material has a specific capacity of more than 300 mAh / g and an energy density of more than 220 Wh / kg at a current density of 1 A / g; at a current density of 150 A / g, its specific capacity is more than 125 mAh / g and its energy density is more than 90 Wh / kg, indicating that the supramolecular organic superstructure material has high specific capacity, rate performance and energy density as a cathode material for aqueous zinc-organic batteries.

[0072] Functions and Effects of the Embodiments

[0073] According to Examples 1 to 3, through a method for preparing a supramolecular organic superstructure material of the present invention, cyanuric acid and 1,3,5-triazine-2,4,6-triamine are used as building blocks, and the two are successfully prepared through hydrogen bonding and π-π stacking in a mixed solvent of dimethyl sulfoxide and N-methylpyrrolidone. The supramolecular organic superstructure material has a three-dimensional open flower-like microstructure, which can provide more exposed carbonyl active sites and convenient ion diffusion pathways. Its excellent electronic conductivity and mechanical strength improve the electron transfer efficiency and can inhibit its dissolution in the electrolyte; and, compared with conventional organic materials for storing Zn 2+ The ion mechanism is different. The hydrogen bond network connected in the supramolecular organic superstructure material of the present invention can overcome the high reaction energy barrier to solvate Zn 2+ The slow interfacial charge transfer caused by ions can effectively reduce the energy barrier of proton charge transfer and promote the H +Ions migrate rapidly through the Grotthuss mechanism, achieving full utilization of electroactive carbonyl sites, which is beneficial to significantly improve the battery's charge storage performance.

[0074] Furthermore, according to Examples 1 to 3, when the supramolecular organic superstructure material prepared by the present invention is used as a cathode of a zinc-organic battery, the prepared aqueous zinc-organic battery has a specific capacity of up to 300 mAh / g or more and an energy density of up to 250 Wh / kg or more at a current density of 1 A / g, and a capacity retention rate of more than 90% after 50,000 cycles of charge and discharge, showing high specific capacity, energy density and excellent cycle stability.

Claims

1. Application of a supramolecular organic superstructure material in an aqueous zinc-organic battery, characterized in that: The method for preparing supramolecular organic superstructure material comprises the following steps: Step S1, dissolving cyanuric acid and 1,3,5-triazine-2,4,6-triamine in dimethyl sulfoxide and N-methylpyrrolidone and mixing them evenly to obtain a mixed solution; Step S2, stirring the mixed solution, reacting at a preset temperature and a preset time, filtering, washing, and drying after the reaction is completed to obtain the supramolecular organic superstructure material, Wherein, in step S1, the mass ratio of the cyanuric acid: the 1,3,5-triazine-2,4,6-triamine: the dimethyl sulfoxide: the N-methylpyrrolidone is 1:0.9~1.2:50~100:5~10.

2. The use of the supramolecular organic superstructure material according to claim 1 in an aqueous zinc-organic battery, characterized in that: in, In step S2, when the mixed solution is stirred, the stirring speed is 300 rpm to 800 rpm.

3. The use of the supramolecular organic superstructure material according to claim 1 in an aqueous zinc-organic battery, characterized in that: in, In step S2, the preset temperature is 20°C to 50°C, and the preset time is 5 min to 10 min.

4. The use of the supramolecular organic superstructure material according to claim 1 in an aqueous zinc-organic battery, characterized in that: in, In step S2, ethanol is used for washing.

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