A lotus pod shell fiber separator loaded with a triazine framework, its preparation method and application

Abstract

The present invention provides a lotus pod shell fiber separator loaded with a triazine framework. The lotus pod shell rich in cellulose is selected as the raw material. First, nanofiber filaments are obtained by an alkaline digestion method, and then a polymer with a triazine framework is loaded on the surface to prepare a lotus pod shell fiber separator loaded with a triazine framework, which has a richer hydrophilic group - amino group, better mechanical strength, high bending resistance, low electrochemical impedance performance and high ionic conductivity. The combined separator is used in a zinc ion hybrid supercapacitor, which has high specific capacitance storage performance, high stability performance and long cycle service life. The invention has good commercial prospects.

Description

Technical Field

[0001] The present invention relates to a separator, and particularly to a separator prepared from lotus seedpod as a raw material, belonging to the technical field of comprehensive utilization of agricultural and forestry waste resources to prepare separator materials. Background Art

[0002] Currently, the high cost and safety issues of lithium-ion batteries (LIBs) have seriously hindered their large-scale application. Zinc-ion batteries (AZIBs) using mildly acidic aqueous electrolytes are considered a promising alternative to LIBs, and their advantages mainly include: (1) abundant zinc resources and low cost, (2) zinc has large conductivity, energy density, and low redox potential, (3) AZIBs use aqueous electrolytes, are not flammable, and are safer. However, due to reasons such as zinc dendrite growth, hydrogen evolution, and surface passivation, zinc metal is unstable, resulting in low power density, low specific capacitance, low coulombic efficiency, and insufficient cycle life; and uncontrolled zinc dendrite growth and adverse side reactions greatly reduce the service life of AZIBs, hindering the practical application of AZIBs. In addition, the current research on traditional supercapacitors is relatively mature. Contrary to the characteristics of zinc-ion batteries, their advantages are mainly excellent power density and high mass specific capacitance. At the same time, such energy storage materials can still maintain high stability under multiple charge and discharge cycles; however, low energy density and conductivity are problems faced by most traditional supercapacitors.

[0003] To overcome the above problems, researchers at home and abroad have proposed a series of strategies. Such as various zinc anode protection strategies: among them, surface modification of the zinc anode is an effective way to reconstruct the electrolyte-anode interface; the reported protective layers include inorganic metal compounds, organic polymers, hydrogels, etc. However, most coatings increase the interfacial resistance and exhibit low ionic conductivity. And inorganic composite layers generally lack elasticity and flexibility, and inevitably damage their stable performance during long-term zinc plating / stripping processes. Some researchers have also proposed combining zinc-ion batteries with traditional supercapacitors to form zinc-ion hybrid supercapacitors. Zinc-ion hybrid capacitors effectively combine the advantages of zinc-ion batteries and supercapacitors, can simultaneously achieve high energy density and high power density, and can make up for the defects of zinc-ion batteries and traditional supercapacitors at the same time. However, it should be noted that the aqueous zinc-ion hybrid capacitors in the prior art still have relatively low specific capacitance, and the growth of zinc anode dendrites and the occurrence of side reactions are still the main lifespan problems faced in improving zinc-ion hybrid supercapacitors, hindering the further development of zinc-ion hybrid supercapacitors in practical applications.

[0004] To overcome this problem, methods such as coating zinc anodes with protective layers, modifying diaphragms, and using electrolyte additives are usually adopted. It should be noted that the performance of the diaphragm has a great impact on the battery performance because the diaphragm isolates the cathode and the anode, is in close contact with both electrodes, and provides a transmission path for electrolyte ions. Currently, glass fiber filter paper is the most commonly used type of diaphragm. However, this diaphragm has low mechanical strength, is fragile, has large and uneven pores, high electrochemical impedance resistance, low conductivity of the capacitor formed, is prone to the formation of zinc dendrites and penetration of the membrane diaphragm, has a short service life, and poor stability. Summary of the Invention

[0005] In view of the deficiencies of the prior art and the characteristics of cellulose such as high mechanical strength, excellent hydrophilicity, and biodegradability, the present invention provides a lotus seedpod fiber diaphragm loaded with a triazine framework. First, lotus seedpods rich in cellulose are selected as raw materials. First, nanofiber filaments are obtained by an alkaline digestion method, and then a polymer containing a triazine framework is loaded on the surface to prepare a lotus seedpod fiber diaphragm loaded with a triazine framework. The invented new cellulose diaphragm will have more abundant hydrophilic groups - amino groups, more excellent mechanical strength, high bending resistance, low electrochemical impedance performance, and high ionic conductivity. The combined fiber diaphragm is used in zinc-ion hybrid supercapacitors to achieve the efficient recycling of waste resources on the diaphragms of energy storage devices in an economical, environmentally friendly, and easy-to-operate manner. The preparation method is simple and low-cost. Compared with traditional glass fiber diaphragms, the present invention not only realizes the effective recycling of agricultural and forestry waste resources but can also be used as a cathode and anode separation device for various energy storage devices. When applied to zinc-ion hybrid supercapacitors, due to the excellent low-resistance impedance, high ion transport efficiency, and water wettability of this lotus seedpod fiber diaphragm; the specific capacitance storage performance and cycle stability performance of the zinc-ion hybrid supercapacitor are high. Most importantly, the lotus seedpod fiber diaphragm after being loaded with a triazine framework will effectively inhibit the dendritic growth of zinc ions at the anode and the occurrence of side reactions, greatly improving the cycle service life of the device. The invention has good commercial prospects.

[0006] According to the first embodiment provided by the present invention, a lotus seedpod fiber diaphragm loaded with a triazine framework is provided.

[0007] A lotus seedpod fiber diaphragm loaded with a triazine framework is prepared by the following method: The lotus seedpods are treated by an alkaline digestion method to obtain nanofiber filaments, and then the obtained nanofiber filaments are loaded with a triazine polymer to obtain a lotus seedpod fiber diaphragm loaded with a triazine framework.

[0008] In the present invention, for the lotus seedpod fiber diaphragm loaded with a triazine framework, it is proved by contact angle measurement that the time taken for the contact angle to return to 0° does not exceed 150 ms, preferably does not exceed 120 ms, and more preferably does not exceed 100 ms.

[0009] In the present invention, the bending test angle of the lotus pod shell fiber separator carrying the triazine framework is not less than 120°, preferably not less than 180°, and more preferably not less than 240°.

[0010] In the present invention, the thickness of the lotus pod shell fiber separator carrying the triazine framework is not higher than 50 μm, preferably not higher than 40 μm, and more preferably not higher than 30 μm.

[0011] In the present invention, for the lotus pod shell fiber separator carrying the triazine framework, electrochemical tests prove that the electrochemical impedance of this lotus pod shell fiber separator does not exceed 300 Ω, preferably does not exceed 200 Ω, and more preferably does not exceed 150 Ω.

[0012] In the present invention, the ionic conductivity of the lotus pod shell fiber separator carrying the triazine framework is not less than 18 μS·cm –1 , preferably not less than 20 μS·cm –1 , more preferably not less than 22 μS·cm –1 .

[0013] According to the second embodiment provided by the present invention, a method for preparing a lotus pod shell fiber separator carrying a triazine framework is provided.

[0014] A method for preparing a lotus pod shell fiber separator carrying a triazine framework or a method for preparing the lotus pod shell fiber separator carrying the triazine framework described in the first embodiment, this method includes the following steps:

[0015] (1) Pretreatment of lotus pod shell: First, crush the lotus pod shell, then wash and dry it to obtain the pretreated lotus pod shell;

[0016] (2) Fibrosis treatment: Immerse the pretreated lotus pod shell in an alkali solution, heat it for reaction, separate and wash it, and obtain nanofiber filaments after separation;

[0017] (3) Separator preparation: Immerse the nanofiber filaments in an alcoholic sodium hydroxide solution of a triazine compound, react, and obtain a lotus pod shell fiber separator carrying a triazine framework after separation.

[0018] In the present invention, the lotus pod shell is a waste lotus pod shell.

[0019] In the present invention, the alkali solution is potassium hydroxide or sodium hydroxide.

[0020] Preferably, the concentration of the alkali solution is 1 - 10 mol / L, preferably 2 - 8 mol / L, and more preferably 5 - 7 mol / L.

[0021] In the present invention, the triazine compound is a mixture of monomer I and monomer II (alternatively, the triazine compound is a triazine polymer constructed from monomer I and monomer II), wherein monomer I is one or more of melamine, cyanuric acid, or thiocyanuric acid, and monomer II is cyanuric chloride; preferably, monomer I is melamine and cyanuric acid, and more preferably melamine.

[0022] In the present invention, the sodium hydroxide alcohol solution is an ethanol solution of sodium hydroxide.

[0023] Preferably, in the sodium hydroxide alcohol solution of the triazine compound, the concentration of monomer I is 0.1 - 1 mol / L, preferably 0.2 - 0.8 mol / L, and more preferably 0.4 - 0.6 mol / L. The concentration of monomer II is 0.1 - 1 mol / L, preferably 0.2 - 0.8 mol / L, and more preferably 0.4 - 0.6 mol / L. The concentration of sodium hydroxide is 0.2 - 2 mol / L, preferably 0.4 - 1.6 mol / L, and more preferably 0.8 - 1.2 mol / L.

[0024] In the present invention, the mass dosage of the pretreated lotus seedpod shell to the volume dosage of the alkali solution is 1 - 5 g: 1 - 100 ml, preferably 1.5 - 4.5 g: 2 - 50 ml, and more preferably 2 - 3 g: 3 - 20 ml.

[0025] In the present invention, the mass dosage of the nanofiber filaments to the volume dosage of the sodium hydroxide alcohol solution of the triazine compound is 1 - 5 g: 1 - 50 ml, preferably 1.5 - 4.5 g: 2 - 45 ml, and more preferably 2 - 3 g: 7 - 40 ml.

[0026] Preferably, step (1) is specifically: first, break the lotus seedpod shell into tuber granules with a particle size of 0.5 - 2 cm, then wash it 1 - 10 times with pure water, separate by suction filtration, and dry it in a vacuum drying oven at 40 - 80 °C for 6 - 24 h to obtain the pretreated lotus seedpod shell.

[0027] Preferably, step (2) is specifically: immerse the pretreated lotus seedpod shell in the alkali solution, and react in a high-pressure steam pot or a high-pressure reactor at 100 - 180 °C and a pressure of 1 - 2 MPa for 20 - 60 h, and perform solid-liquid separation by suction filtration; bleach it with a 20 wt.% - 40 wt.% hydrogen peroxide solution, wash it with pure water until neutral, and obtain the nanofiber filaments after suction filtration separation.

[0028] Preferably, step (3) is specifically as follows: Immerse the nanofiber filaments in an alcoholic solution of sodium hydroxide of triazine compound, and carry out ice bath (or water bath) magnetic stirring reaction for 0.5 - 8 h in a magnetic stirring device under the conditions of 0 - 30 °C and 200 - 1000 r / s, carry out suction filtration and separation, and dry in a vacuum drying oven at 40 - 80 °C for 6 - 24 h to obtain a lotus seedpod shell fiber diaphragm carrying a triazine framework.

[0029] According to the third embodiment provided by the present invention, there is provided a use of a lotus seedpod shell fiber diaphragm carrying a triazine framework.

[0030] According to the use of the lotus seedpod shell fiber diaphragm carrying a triazine framework described in the first embodiment or the lotus seedpod shell fiber diaphragm carrying a triazine framework prepared by the method described in the second embodiment, use the lotus seedpod shell fiber diaphragm carrying a triazine framework as the anode and cathode diaphragms of a zinc ion hybrid supercapacitor.

[0031] According to the fourth embodiment provided by the present invention, there is provided a zinc ion hybrid supercapacitor

[0032] For a zinc ion hybrid supercapacitor, assemble the lotus seedpod shell fiber diaphragm carrying a triazine framework described in the first embodiment or the lotus seedpod shell fiber diaphragm carrying a triazine framework prepared by the method described in the second embodiment in the order of "zinc sheet anode - diaphragm - carbon cathode", dropwise add an electrolyte, and obtain a zinc ion hybrid supercapacitor after standing, drying and encapsulation.

[0033] In the present invention, the electrolyte in the zinc ion hybrid supercapacitor is one or more of aqueous ZnSO4, aqueous Zn(CF3SO3)2, and aqueous ZnCl2, preferably aqueous ZnSO4 or aqueous Zn(CF3SO3)2, and more preferably aqueous ZnSO4.

[0034] In the present invention, for the zinc ion hybrid supercapacitor, at a current density of 0.2 A·g -1 , its specific capacitance storage performance is not less than 100 mA·h·g -1 , preferably not less than 105 mA·h·g -1 , and more preferably not less than 110 mA·h·g -1 .

[0035] In the present invention, for the zinc ion hybrid supercapacitor, at a current density of 5 A·g -1 , after 5000 - cycle tests, its cycle stability performance is not less than 85%, preferably not less than 88%, and more preferably not less than 90%.

[0036] In the present invention, for the zinc ion hybrid supercapacitor, after 5000 cycles of charge and discharge, the growth amount of dendritic by-products at the zinc positive electrode does not exceed 25% of the original mass of the zinc sheet, preferably does not exceed 20% of the original mass of the zinc sheet, and more preferably does not exceed 15% of the original mass of the zinc sheet.

[0037] In the present invention, the growth thickness of the lotus pod shell is 4 - 15 cm, preferably 4 - 10 cm, and more preferably 4 - 6 cm. The average tensile strength of the lotus pod shell is not less than 8.0 MPa, preferably higher than 10.0 MPa, and more preferably higher than 12.0 MPa.

[0038] In the present invention, bleaching is carried out using a 20 wt.% - 40 wt.% hydrogen peroxide solution. The volume ratio of hydrogen peroxide to the mass of nanofiber filaments after alkali treatment is 1 - 1000 ml:1 g, preferably 2 - 500 ml:1 g, and more preferably 4 - 200 ml:1 g.

[0039] In the present invention, the time of basic digestion treatment is not less than 16 h, preferably not less than 28 h, and more preferably not less than 20 h. The temperature of basic digestion treatment is 100 - 180 °C, preferably 120 - 160 °C, and more preferably a constant temperature of 140 °C.

[0040] Preferably, the device for basic digestion treatment is a high-temperature and high-pressure device, preferably a high-pressure steam pot or a high-pressure reaction kettle.

[0041] Preferably, the device for ice bath stirring treatment is a magnetic stirring device, preferably a heating magnetic stirrer.

[0042] Preferably, the drying is all carried out in a vacuum drying oven. The drying temperature is 40 - 80 °C, preferably a constant temperature drying at 60 °C; the drying duration is not less than 4 h, preferably not less than 6 h.

[0043] In the present invention, the tensile strength of the waste lotus pod shell fiber diaphragm loaded with triazine framework obtained is not less than 6.0 MPa, preferably not less than 9.0 MPa, and more preferably not less than 12.0 MPa.

[0044] Preferably, using the waste lotus pod shell fiber diaphragm loaded with triazine framework as the diaphragm of the zinc ion hybrid supercapacitor specifically includes: cutting the waste lotus pod shell fiber diaphragm loaded with triazine framework into a standard size, then fully soaking it in an aqueous electrolyte, and finally assembling it in the order of zinc sheet anode - diaphragm - carbon cathode, and obtaining the zinc ion hybrid supercapacitor after standing, drying and encapsulation.

[0045] In the present invention, the carbon cathode is made of one or more of commercial activated carbon, porous biomass carbon, graphene, carbon nanotubes, etc., preferably porous biomass carbon and graphene, and more preferably porous biomass carbon. For example, lotus pod biomass carbon is used as the carbon cathode material.

[0046] In the prior art, although the new zinc-ion hybrid supercapacitor combines the advantages of the original zinc-ion battery and the traditional supercapacitor in many aspects, dendritic growth and side reactions still occur at the zinc anode end during operation, which remains the main problem at present. Therefore, on the premise of ensuring the original advantages, the development of a separator that can inhibit dendritic growth of the zinc anode has become an important research hotspot. Secondly, the crop - lotus pod grows widely in the central-south and eastern regions of China. It is rich in fiber content and is an excellent choice for making high-quality paper manuscripts. It is learned that after removing the lotus seeds, most of the remaining outer shells of the lotus pods are usually disposed of by landfill and incineration at high temperature, which causes serious waste of resources and air pollution.

[0047] The present invention uses agricultural and forestry waste - lotus pod shell as a raw material, first prepares nanofiber filaments, and then prepares a modified separator by loading a triazine framework polymer. This operation method is simple and low-cost. Compared with the traditional glass fiber separator, the present invention not only realizes the effective recycling of agricultural and forestry waste resources, but also the prepared separator has better bending resistance and high mechanical properties, and can be used as the anode and cathode separation device of various energy storage devices. When applied to a zinc-ion hybrid supercapacitor, the separator exhibits excellent low-resistance impedance, high ion transport efficiency, and water wettability. Most importantly, the separator loaded with the triazine framework will effectively inhibit the dendritic growth and side reactions of zinc ions at the anode, greatly improving the cycle service life of the device. In addition, no technical literature has been found on using agricultural and forestry waste - lotus pod shell as a raw material to prepare a modified separator by loading a polymer with a triazine framework.

[0048] In the present invention, the agricultural and forestry waste - lotus pod shell refers to the lotus pod outer shell that has more characteristics of an anti-bending separator in terms of growth cycle, fiber content, and fiber thickness, such as a lotus pod that has just entered the fruit ripening period. It is preferably the fibrous structure (spongy pith) in the middle after removing the outer skin of the lotus pod shell.

[0049] In the present invention, the growth thickness of the waste lotus pod shell refers to the average value of the diameter of the lotus pod outer shell measured with a tape measure, and the thickness refers to the average value measured with a micrometer.

[0050] In the present invention, the pretreatment in step 1) of the preparation method further includes washing and drying the lotus pod shell, then removing the outer skin, and cutting the internal spongy pith into uniform lengths and sizes.

[0051] In the present invention, in step 2) of the preparation method, the waste lotus seedpods are treated by high-temperature and high-pressure alkaline hydrolysis using potassium hydroxide or sodium hydroxide. The purpose is to decompose lignin, pectin and other water-soluble substances in the shell. These impurities are dissolved and removed by the alkali solution, and the cellulose that is not decomposed (insoluble in the alkali solution) is extracted therefrom to obtain (lotus seedpod) nanofibers. The purpose of using hydrogen peroxide is to neutralize the residual potassium hydroxide solution after the previous treatment, and at the same time further oxidize the impurities on the surface of the nanofibers to obtain pure nanofibers; and bleach the nanofibers. Its treatment process is mature and simple, and the effect is obvious.

[0052] Generally, the main components of the anode and cathode diaphragms used in assembling energy storage devices are fibers. This is because fibers are one of the most widely distributed substances in plants and are the basic substances that make up the plant cell wall. Cellulose is mixed with hemicellulose, lignin, pectin, etc. to form the main body of the fiber. The basic ring of the cellulose macromolecule is combined with each other by β-type anhydrous D-glucose-based 1,4-glycosidic bonds. There are three free alcoholic hydroxyl groups (-OH) on its basic ring, and hydrogen bonds can be formed between the macromolecular chains. For the diaphragm after alkaline digestion, the large amount of cellulose composition has an important impact on its hygroscopicity, solubility and ion transport ability, etc. In the present invention, the waste lotus seedpods themselves contain rich cellulose and are an excellent choice for preparing high-quality diaphragms.

[0053] In the present invention, in step 2) of the preparation method, the bleached product is washed repeatedly until neutral to avoid the influence of the too acidic or too alkaline pH of the nanofibers on the loading process in step 3).

[0054] In the present invention, the optimal composition of the triazine compound in step 3) of the preparation method is: monomer I: melamine; monomer II: cyanuric chloride; the polymerization process is carried out in an alcoholic sodium hydroxide solution, and the obtained polycondensation product is a triazine framework polymer in which multiple triazine rings and multiple imino groups (-NH-) are connected end to end in sequence. At the same time, there are still a small amount of unreacted amino groups (-NH2) at the ends of the polymer molecules.

[0055] In the present invention, in step 3) of the preparation method, by treating with the polymerization product containing the triazine framework, the purpose is to enable the surface of the nanofibers to carry the triazine framework structure. First, there are a large number of alcoholic hydroxyl groups on the surface of the nanofibers, and the triazine framework polymer has a large number of imino groups (-NH-) and a small amount of amino groups (-NH2). During the ice bath (or water bath) activation treatment process of the two substances, the hydroxyl group and the amino group can be effectively combined by hydrogen bonding, so that the polymer of the triazine framework is carried on the nanofibers, and further suction filtration is carried out to form a diaphragm carrying the triazine framework. Importantly, when the energy storage device is working, the appearance of the triazine framework will effectively combine with OH - combined to prevent its enrichment at the zinc anode end and the electrolytically generated Zn2+ Combined to form Zn(OH)₂ by-products, achieving the effect of preventing the growth of zinc dendrites and side reactions.

[0056] In the present invention, an ice bath (or water bath) stirring treatment is adopted in step 3) of the preparation method, aiming to accelerate the combination of nanofiber filaments and surface amino groups on the triazine framework polymer to form hydrogen bonds and improve the stability of the loading process.

[0057] In the present invention, the waste lotus seedpod diaphragm loaded with the triazine framework has a high level of water wettability. It is proved by contact angle testing that the time taken for the contact angle to recover to 0 °C does not exceed 150 ms, which is beneficial to improving the wetting effect between the electrolyte and the diaphragm. It is proved by bending testing that the anti-bending angle of the diaphragm is not less than 120°; through electrochemical testing, the electrochemical impedance of the diaphragm does not exceed 300 Ω, and the ionic conductivity is not less than 10 μS·cm –1 , all indicating that the diaphragm has excellent electrolyte ion transport ability. When the fiber diaphragm loaded with the triazine framework is used as the anode and cathode diaphragms of a zinc-ion hybrid supercapacitor, at a current density of 0.2 A·g -1 , the specific capacitance storage performance of its zinc-ion hybrid supercapacitor is not less than 70 mAh·g -1 ; at a current density of 5 A·g -1 , after 5000 cycles of testing, its cycle stability performance is not less than 80%, and the growth amount of dendritic by-products at the zinc anode end does not exceed 45% of the original mass of the zinc sheet. Compared with the ordinary fiber diaphragm without loading the triazine framework, the waste lotus seedpod fiber diaphragm loaded with the triazine framework prepared in the present invention will exhibit more excellent water wettability, conductivity and device durability, which benefits from the unique structure of the polymer with the attached triazine framework and the successful loading.

[0058] Compared with the prior art, the technical solution provided by the present invention has the following beneficial technical effects:

[0059] 1. The present invention uses agricultural and forestry waste - lotus seedpods as raw materials and triazine framework polymer as the doping agent for loading, and prepares a waste lotus seedpod fiber diaphragm loaded with the triazine framework under ice bath (or water bath) stirring conditions. This technical method is simple to operate and low in cost, and can effectively realize the recycling of agricultural and forestry waste resources.

[0060] 2. The agricultural and forestry waste - lotus seedpods used in the present invention itself has a large amount of cellulose content and strong mechanical properties, which is an excellent choice for preparing lotus seedpod fiber diaphragms.

[0061] 3. In the present invention, the waste lotus seedpod shells are modified with triazine polymers, which have better water wettability and ionic conductivity compared to untreated ones. In addition, when the invention is used as a separator for zinc-ion hybrid supercapacitors, it can effectively inhibit dendritic growth at the zinc positive electrode, greatly promoting the service life of energy storage devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a flowchart for manufacturing the lotus seedpod shell fiber separator with a triazine framework of the present invention.

[0063] Figure 2 It is a schematic structural diagram of the raw materials for manufacturing the lotus seedpod shell fiber separator of the present invention: nanofiber filaments and the polymerization process of the triazine framework.

[0064] Figure 3 It is a contact angle test diagram of the lotus seedpod shell fiber separator with a triazine framework prepared in Example 1: initial stage.

[0065] Figure 4 It is a contact angle test diagram of the lotus seedpod shell fiber separator with a triazine framework prepared in Example 1: after 54 ms, the contact angle of the separator returns to 52.5°.

[0066] Figure 5 It is a contact angle test diagram of the lotus seedpod shell fiber separator with a triazine framework prepared in Example 1: after 98.4 ms, the contact angle of the separator returns to 0°.

[0067] Figure 6 It is a performance diagram of the bending resistance of the lotus seedpod shell fiber separator with a triazine framework prepared in Example 1.

[0068] Figure 7 It is a performance diagram of the bending resistance of the commercial glass fiber separator in Comparative Example 2.

[0069] Figure 8 It is an electrochemical impedance diagram of the waste lotus seedpod shell fiber separator with a triazine framework prepared in Example 1.

[0070] Figure 9 It is an electrochemical galvanostatic charge-discharge curve diagram of the waste lotus seedpod shell fiber separator with a triazine framework prepared in Example 1.

[0071] Figure 10 It is a schematic structural diagram when the separator with a triazine framework prepared in Example 1 is applied to a zinc-ion hybrid supercapacitor.

[0072] Figure 11 It is a cyclic stability performance diagram when the separator with a triazine framework prepared in Example 1 is applied to a zinc-ion hybrid supercapacitor. DETAILED DESCRIPTION OF THE INVENTION

[0073] The technical solutions of the present invention will be illustrated by way of examples below. The scope of protection claimed by the present invention includes but is not limited to the following embodiments.

[0074] According to the first embodiment provided by the present invention, a lotus pod shell fiber separator loaded with a triazine framework is provided.

[0075] A lotus pod shell fiber separator loaded with a triazine framework, which is prepared by the following method: treating the lotus pod shell by base hydrolysis method to obtain nanofiber filaments, and then reacting the obtained nanofiber filaments with a triazine compound to obtain the lotus pod shell fiber separator.

[0076] According to the second embodiment provided by the present invention, a method for preparing a lotus pod shell fiber separator loaded with a triazine framework is provided.

[0077] A method for preparing a lotus pod shell fiber separator loaded with a triazine framework or a method for preparing the lotus pod shell fiber separator loaded with a triazine framework described in the first embodiment, the method comprising the following steps:

[0078] (1) Pretreatment of lotus pod shell: First, the lotus pod shell is crushed, then washed and dried to obtain the pretreated lotus pod shell;

[0079] (2) Fibrosis treatment: impregnating the pretreated lotus pod shell in an alkali solution, heating for reaction, separating and washing, and obtaining nanofiber filaments after separation;

[0080] (3) Separator preparation: impregnating the nanofiber filaments in a sodium hydroxide alcohol solution of a triazine compound, reacting, and separating to obtain a lotus pod shell fiber separator loaded with a triazine framework.

[0081] In the present invention, the lotus pod shell is a waste lotus pod shell.

[0082] In the present invention, the alkali solution is potassium hydroxide or sodium hydroxide.

[0083] Preferably, the concentration of the alkali solution is 1-10 mol / L, preferably 2-8 mol / L, more preferably 5-7 mol / L.

[0084] In the present invention, the triazine compound is a mixture of monomer I and monomer II, wherein monomer I is one or more of melamine, cyanuric acid or thiocyanuric acid, and monomer II is cyanuric chloride; preferably monomer I is melamine, preferably monomer II is cyanuric chloride; the sodium hydroxide alcohol solution is an ethanol solution of sodium hydroxide.

[0085] In the present invention, the triazine framework is a triazine polymer constructed from monomer I and monomer II, where monomer I is one or more of melamine, cyanuric acid, or thiocyanuric acid, and monomer II is cyanuric chloride; preferably, monomer I is melamine and cyanuric acid, and more preferably, it is melamine.

[0086] Preferably, in the sodium hydroxide alcohol solution of the triazine compound, the concentration of monomer I is 0.1 - 1 mol / L, preferably 0.2 - 0.8 mol / L, and more preferably 0.4 - 0.6 mol / L; the concentration of monomer II is 0.1 - 1 mol / L, preferably 0.2 - 0.8 mol / L, and more preferably 0.4 - 0.6 mol / L; the concentration of sodium hydroxide is 0.2 - 2 mol / L, preferably 0.4 - 1.6 mol / L, and more preferably 0.8 - 1.2 mol / L.

[0087] In the present invention, the mass dosage of the pretreated lotus seedpod shell to the volume dosage of the alkali solution is 1 - 5 g:1 - 100 ml, preferably 1.5 - 4.5 g:2 - 50 ml, and more preferably 2 - 3 g:3 - 20 ml.

[0088] In the present invention, the mass dosage of the nanofiber filaments to the volume dosage of the sodium hydroxide alcohol solution of the triazine compound is 1 - 5 g:1 - 50 ml, preferably 1.5 - 4.5 g:2 - 45 ml, and more preferably 2 - 3 g:7 - 40 ml.

[0089] Preferably, step (1) is specifically as follows: First, crush the lotus seedpod shell into tuber granules with a particle size of 0.5 - 2 cm, then wash it 1 - 10 times with pure water, perform suction filtration separation, and dry it in a vacuum drying oven at 40 - 80 °C for 6 - 24 h to obtain the pretreated lotus seedpod shell.

[0090] Preferably, step (2) is specifically as follows: Immerse the pretreated lotus seedpod shell in the alkali solution, and react in an autoclave or high-pressure reactor at 100 - 180 °C and a pressure of 1 - 2 MPa for 20 - 60 h, then perform solid-liquid separation by suction filtration; bleach it with a 20 wt.% - 40 wt.% hydrogen peroxide solution, wash it with pure water until neutral, and perform suction filtration separation to obtain the nanofiber filaments.

[0091] Preferably, step (3) is specifically as follows: Immerse the nanofiber filaments in the sodium hydroxide alcohol solution of the triazine compound, and perform ice bath (or water bath) magnetic stirring reaction in a magnetic stirring device at 0 - 30 °C and 200 - 1000 r / s for 0.5 - 8 h, then perform suction filtration separation, and dry it in a vacuum drying oven at 40 - 80 °C for 6 - 24 h to obtain the lotus seedpod shell fiber diaphragm loaded with the triazine framework.

[0092] According to the third implementation scheme provided by the present invention, there is provided a use of a lotus pod shell fiber diaphragm carrying a triazine framework.

[0093] Use the lotus pod shell fiber diaphragm carrying a triazine framework described in the first implementation scheme or the lotus pod shell fiber diaphragm carrying a triazine framework prepared by the method described in the second implementation scheme, and use the lotus pod shell fiber diaphragm carrying a triazine framework as the anode and cathode diaphragms of a zinc ion hybrid supercapacitor.

[0094] According to the fourth implementation scheme provided by the present invention, there is provided a zinc ion hybrid supercapacitor

[0095] A zinc ion hybrid supercapacitor is assembled in the order of "zinc sheet anode - diaphragm - carbon cathode" with the lotus pod shell fiber diaphragm carrying a triazine framework described in the first implementation scheme or the lotus pod shell fiber diaphragm carrying a triazine framework prepared by the method described in the second implementation scheme, and after dropping the electrolyte, standing, drying and encapsulating, a zinc ion hybrid supercapacitor is obtained.

[0096] In the present invention, the electrolyte in the zinc ion hybrid supercapacitor is one or more of aqueous ZnSO4, aqueous Zn(CF3SO3)2, and aqueous ZnCl2, preferably aqueous ZnSO4 or aqueous Zn(CF3SO3)2, and more preferably aqueous ZnSO4.

[0097] In the embodiments of the present invention, the lotus pod shells are collected from Yuhu District, Xiangtan City, Hunan Province.

[0098] The reagents used in the examples include:

[0099] KOH: Tianjin Fuyu Fine Chemical Co., Ltd., AR.

[0100] NaOH: Tianjin Fuyu Fine Chemical Co., Ltd., AR.

[0101] 30% hydrogen peroxide solution (hydrogen peroxide): Aladdin Chemical Reagent Co., Ltd., AR.

[0102] Absolute ethanol: Aladdin Chemical Reagent Co., Ltd., AR.

[0103] Melamine: Anychem Chemical Reagent Co., Ltd., AR.

[0104] Cyanuric acid: Anychem Chemical Reagent Co., Ltd., AR.

[0105] Trithiocyanuric acid: Anychem Chemical Reagent Co., Ltd., AR.

[0106] Cyanuric chloride: Anychem Chemical Reagent Co., Ltd., AR.

[0107] Glass fiber membrane: 1823-110-whatman GF / D, Shanghai Gensheng Biotechnology Co., Ltd.

[0108] The analytical instruments required in the examples include:

[0109] Contact angle / surface tension tester: LAUDA Wissenschaftliche Geräte GmbH, LSA-100.

[0110] Electrochemical workstation: Shanghai Chenhua Instrument Co., Ltd., CHI760D.

[0111] The calculation formulas required in the examples are as follows:

[0112] The ionic conductivity of the membrane is calculated by the following equation:

[0113] σ = L / RS

[0114] where L (cm) is the thickness of the cellulose membrane, S (cm 2 ) is the contact area between the membrane and the electrolyte, and R (ohm) is the impedance obtained from the Nyquist plot in the electrochemical impedance test.

[0115] Example 1

[0116] Take the whole discarded lotus pod shell with a growth diameter of 5 cm, crush it into granules with a size of 1 cm tubers, wash it repeatedly with ultrapure water and place it in a vacuum drying oven at 60 °C for 12 h. Weigh 30 g of lotus pod shell granules and immerse them in a reaction kettle containing 60 mL of 6 mol / L potassium hydroxide solution, and react under high temperature and high pressure conditions at 140 °C for 30 h; take out the reactants at room temperature, filter them and add 8 ml of 30 wt.% hydrogen peroxide solution for bleaching; then wash them repeatedly with ultrapure water until the solution is neutral, and filter to obtain nanofiber filaments. Take 10 g of nanofiber filaments and immerse them in 60 mL of an ethanol solution containing 0.5 mol / L melamine, 0.5 mol / L cyanuric chloride and 1 mol / L sodium hydroxide, and stir magnetically in an ice bath at 10 °C and 500 r / s for 4 h, filter the product, and dry it in a vacuum drying oven at 60 °C for 12 h to obtain a lotus pod shell fiber membrane loaded with a triazine framework.

[0117] The lotus pod shell fiber diaphragm loaded with triazine framework was air-dried naturally and cut into circular pieces with a diameter of 1.5 cm and a thickness of 30 μm. 5-10 drops of 1 mol / L aqueous ZnSO4 solution were added and soaked for more than 12 h. Zinc sheets and lotus pod porous carbon of corresponding specifications were weighed, 24 mg and 1.5 mg respectively. Subsequently, the lotus pod shell fiber diaphragm was placed between the anode and cathode in the order of "sandwich structure" (zinc sheet anode - triazine polymer diaphragm - lotus pod porous carbon cathode), and encapsulated with a CR2032 type button battery case to form a zinc ion hybrid supercapacitor.

[0118] The prepared lotus pod shell fiber diaphragm loaded with triazine framework Figure 3-5 showed ideal water wettability as shown in the figure, and the contact angle could recover to 0° after 98.4 ms. Figure 6 It was shown that under a bending angle of 360°, no obvious fracture occurred in the diaphragm. Figure 8 It was shown that the electrochemical impedance resistance of the diaphragm was only 134 Ω. Through experiments, its ionic conductivity was as high as 22.39 μS cm –1 , indicating that the membrane had excellent ionic transport efficiency. Figure 9 It was shown that when the diaphragm was applied to the zinc ion hybrid supercapacitor, at a current density of 0.2 A·g -1 , its mass specific capacitance storage performance reached 112 mA·h·g -1 . Figure 11 It was shown that when the diaphragm was applied to the zinc ion hybrid supercapacitor, after 5000 cycles of utilization, the capacitance retention rate of the device could be as high as 92%. The growth amount of by-products at the zinc anode end was only 10% of the original mass of the zinc sheet.

[0119] Example 2

[0120] The whole discarded lotus pod shell with a growth diameter of 5 cm was taken, broken into granules with a size of 1 cm tuber, washed repeatedly with ultrapure water and placed in a vacuum drying oven at 60 °C for 12 h. 30 g of lotus pod shell granules were weighed and impregnated in a reaction kettle containing 60 mL of 6 mol / L potassium hydroxide solution, and reacted under high temperature and high pressure conditions at 140 °C for 30 h. The reactants were taken out at room temperature, filtered by suction, and 8 ml of 30 wt.% hydrogen peroxide solution was added for bleaching; then washed repeatedly with ultrapure water until the solution was neutral, and nanofibrous filaments were obtained by suction filtration. 10 g of nanofibrous filaments were impregnated in 60 mL of an ethanol solution containing 0.5 mol / L cyanuric acid, 0.5 mol / L cyanuric chloride and 1 mol / L sodium hydroxide, and magnetically stirred in an ice bath at 10 °C and 500 r / s for 4 h. The product was filtered by suction and dried in a vacuum drying oven at 60 °C for 12 h to obtain a lotus pod shell fiber diaphragm loaded with triazine framework.

[0121] The lotus pod shell fiber separator loaded with the triazine framework is naturally air-dried and cut into a circular shape with a diameter of 1.5 cm and a thickness of 30 μm. 5-10 drops of 1 mol / L aqueous ZnSO4 solution are added and fully soaked for more than 12 h. Zinc sheets and lotus pod porous carbon of the corresponding specifications are taken and weighed 24 mg and 1.5 mg respectively. Subsequently, the lotus pod shell fiber separator is placed between the anode and the cathode in the order of "sandwich structure" (zinc sheet anode - triazine polymer separator - lotus pod porous carbon cathode), and is encapsulated using a CR2032 type button battery case to form a zinc ion hybrid supercapacitor.

[0122] Example 3

[0123] Take the whole discarded lotus pod shell with a growth diameter of 5 cm and break it into granules with a size of 1 cm tuber. Wash it repeatedly with ultrapure water and place it in a vacuum drying oven at 60 °C for 12 h. Weigh 30 g of lotus pod shell granules and immerse them in a reaction kettle containing 60 mL of 6 mol / L potassium hydroxide solution, and react under high temperature and high pressure conditions at 140 °C for 30 h. Take out the reactants at room temperature, filter them by suction, and add 8 ml of 30 wt.% hydrogen peroxide solution for bleaching; then wash them repeatedly with ultrapure water until the solution is neutral, and filter by suction to obtain nanofiber filaments. Take 10 g of nanofiber filaments and immerse them in 60 mL of an ethanol solution containing 0.5 mol / L trithiocyanuric acid, 0.5 mol / L cyanuric chloride, and 1 mol / L sodium hydroxide, and magnetically stir in an ice bath at 10 °C and 500 r / s for 4 h. Filter the product by suction and dry it in a vacuum drying oven at 60 °C for 12 h to obtain a lotus pod shell fiber separator loaded with a triazine framework.

[0124] The lotus pod shell fiber separator loaded with the triazine framework is naturally air-dried and cut into a circular shape with a diameter of 1.5 cm and a thickness of 30 μm. 5-10 drops of 1 mol / L aqueous ZnSO4 solution are added and fully soaked for more than 12 h. Zinc sheets and lotus pod porous carbon of the corresponding specifications are taken and weighed 24 mg and 1.5 mg respectively. Subsequently, the lotus pod shell fiber separator is placed between the anode and the cathode in the order of "sandwich structure" (zinc sheet anode - triazine polymer separator - lotus pod porous carbon cathode), and is encapsulated using a CR2032 type button battery case to form a zinc ion hybrid supercapacitor.

[0125] Example 4

[0126] Take the entire discarded lotus pod shell with a growth diameter of 5 cm, crush it into granules with a tuber size of 1 cm, wash it repeatedly with ultrapure water, and dry it in a 60 °C vacuum drying oven for 12 h. Weigh 30 g of lotus pod shell granules and immerse them in a reaction kettle containing 60 mL of 6 mol / L potassium hydroxide solution, and react under high temperature and high pressure conditions at 140 °C for 30 h. Take out the reactants at room temperature, filter them by suction, and add 8 mL of 30 wt.% hydrogen peroxide solution for bleaching; then wash them repeatedly with ultrapure water until the solution is neutral, and filter by suction to obtain nanofibrous filaments. Take 10 g of nanofibrous filaments and immerse them in 60 mL of an ethanol solution containing 0.5 mol / L melamine, 0.5 mol / L cyanuric acid, 0.5 mol / L cyanuric chloride, and 1 mol / L sodium hydroxide, and magnetically stir in an ice bath at 10 °C and 500 r / s for 4 h. Filter the product by suction and dry it in a 60 °C vacuum drying oven for 12 h to obtain a lotus pod shell fiber diaphragm loaded with a triazine framework.

[0127] Naturally air-dry the above-mentioned lotus pod shell fiber diaphragm loaded with a triazine framework and cut it into a circular shape with a diameter of 1.5 cm and a thickness of 30 μm. Drop 5 - 10 drops of 1 mol / L aqueous ZnSO4 solution and soak it for more than 12 h. Take zinc sheets and lotus porous carbon of corresponding specifications, weigh them as 24 mg and 1.5 mg respectively, and then place the lotus pod shell fiber diaphragm between the anode and cathode in the order of "sandwich structure" (zinc sheet anode - triazine polymer diaphragm - lotus porous carbon cathode), and use a CR2032 type button battery case for encapsulation to form a zinc ion hybrid supercapacitor.

[0128] Example 5

[0129] Repeat Example 1, except that sodium hydroxide is used instead of potassium hydroxide.

[0130] Comparative Example 1

[0131] Take the entire discarded lotus pod shell with a growth diameter of 5 cm, crush it into granules with a tuber size of 1 cm, wash it repeatedly with ultrapure water, and dry it in a 60 °C vacuum drying oven for 12 h. Weigh 30 g of lotus pod shell granules and immerse them in a reaction kettle containing 60 mL of 6 mol / L potassium hydroxide solution, and react under high temperature and high pressure conditions at 140 °C for 30 h. Take out the reactants at room temperature, filter them by suction, and add 8 mL of 30 wt.% hydrogen peroxide solution for bleaching; then wash them repeatedly with ultrapure water until the solution is neutral, and filter by suction to obtain a conventional discarded lotus pod shell fiber diaphragm.

[0132] The above-mentioned conventional waste lotus pod shell fiber diaphragm was naturally air-dried and cut into a circular shape with a diameter of 1.5 cm and a thickness of 30 μm. 5-10 drops of 1 mol / L aqueous ZnSO4 solution were added and fully soaked for more than 12 h. Zinc sheets and lotus pod porous carbon of corresponding specifications were taken, weighed 24 mg and 1.5 mg respectively. Subsequently, the diaphragm was placed between the anode and cathode in the order of "sandwich structure" (zinc sheet anode - conventional diaphragm - lotus pod carbon cathode), and encapsulated with a CR2032 type button battery case to form a zinc-ion hybrid supercapacitor.

[0133] Comparative Example 2

[0134] Directly take a commercial glass fiber diaphragm, cut it into a circular shape with a diameter of 1.5 cm and a thickness of 30 μm. 5-10 drops of 1 mol / L aqueous ZnSO4 solution were added and fully soaked for more than 12 h. Zinc sheets and lotus pod porous carbon of corresponding specifications were taken, weighed 24 mg and 1.5 mg respectively. Subsequently, the diaphragm was placed between the anode and cathode in the order of "sandwich structure" (zinc sheet anode - glass fiber diaphragm - lotus pod carbon cathode), and encapsulated with a CR2032 type button battery case to form a zinc-ion hybrid supercapacitor.

[0135] Note: The production process of the lotus pod carbon cathode used in the above Examples 1-3 and Comparative Examples 1-2 is as follows: Take the whole waste lotus pod shell with a growth diameter of 5 cm, dry it and crush it into powder with a particle size of 120 mesh, and transfer it to a tubular furnace. Under nitrogen protection, the temperature is raised from room temperature to 800 °C at a rate of 5 °C / min, and high-temperature heat treatment is carried out at 800 °C for 2 h. After cooling to room temperature, the sample is taken out. The obtained black product is mixed with 0.5 mol / L hydrochloric acid solution at a mass ratio of 1:60 and stirred at room temperature for 30 min. Then it is washed with deionized water many times until neutral, filtered by suction and placed in a 100 °C vacuum drying oven for drying for 24 h to obtain the lotus pod shell-derived carbon material. Take 0.012 g of the lotus pod shell-derived carbon material, 0.0015 g of acetylene black, and 0.0025 g of polytetrafluoroethylene (60 wt.%) (mass ratio 8:1:1), add a small amount of absolute ethanol (2 mL), and grind finely to obtain a uniformly textured slurry. The slurry is coated on a nickel foam current collector by the coating method to prepare a lotus pod carbon electrode, which is used as the cathode of the zinc-ion hybrid supercapacitor in the above Examples 1-2 and Comparative Examples 1-2.

[0136] Figure 7 It shows that when the diaphragm of Comparative Example 2 is bent at an angle of about 65 °C, obvious fracture phenomenon occurs in the film.

[0137] The following table shows the performance test of the diaphragms prepared in the examples and comparative examples of this application and the zinc-ion hybrid supercapacitors prepared respectively.

[0138]

Claims

1. A method for preparing a lotus pod shell fiber separator loaded with a triazine framework, the method comprising the following steps: (1) Pretreatment of lotus pod shell: First, the lotus pod shell is crushed, then washed and dried to obtain the pretreated lotus pod shell; (2) Fibrosis treatment: The pretreated lotus pod shell is immersed in an alkali solution, heated for reaction, separated and washed, and nanofibers are obtained after separation; (3) Separator preparation: The nanofibers are immersed in a sodium hydroxide alcohol solution of a triazine compound, and an ice bath magnetic stirring reaction is carried out in a magnetic stirring device at 0-30 °C and 200-1000 r / s for 0.5-8 h, followed by suction filtration and separation, and drying in a vacuum drying oven at 40-80 °C for 6-24 h to obtain a lotus pod shell fiber separator loaded with a triazine framework; Wherein: The triazine compound is a mixture of monomer I and monomer II, wherein monomer I is one or more of melamine, cyanuric acid or thiocyanuric acid, and monomer II is cyanuric chloride; the sodium hydroxide alcohol solution is an ethanol solution of sodium hydroxide; in the sodium hydroxide alcohol solution of the triazine compound, the concentration of monomer I is 0.1-1 mol / L, the concentration of monomer II is 0.1-1 mol / L, and the concentration of sodium hydroxide is 0.2-2 mol / L; the mass dosage of the nanofibers and the volume dosage of the sodium hydroxide alcohol solution of the triazine compound are in a ratio of 1-5 g:1-50 ml.

2. The method according to claim 1, wherein: The lotus pod shell is a waste lotus pod shell; and / or The alkali solution is potassium hydroxide or sodium hydroxide; and / or Monomer I is melamine.

3. The method according to claim 1, characterized in that: The concentration of the alkali solution is 1-10 mol / L; and / or In the sodium hydroxide alcohol solution of the triazine compound, the concentration of monomer I is 0.2-0.8 mol / L; the concentration of monomer II is 0.2-0.8 mol / L; the concentration of sodium hydroxide is 0.4-1.6 mol / L.

4. The method according to claim 3, characterized in that: The concentration of the alkali solution is 2-8 mol / L; and / or In the sodium hydroxide alcohol solution of the triazine compound, the concentration of monomer I is 0.4-0.6 mol / L; the concentration of monomer II is 0.4-0.6 mol / L; the concentration of sodium hydroxide is 0.8-1.2 mol / L.

5. The method according to claim 1, characterized in that: The mass dosage of the pretreated lotus pod shell and the volume dosage of the alkali solution are in a ratio of 1-5 g:1-100 ml; and / or The mass dosage of the nanofibers and the volume dosage of the sodium hydroxide alcohol solution of the triazine compound are in a ratio of 1.5-4.5 g:2-45 ml.

6. The method according to claim 5, characterized in that: The mass dosage of the pretreated lotus pod shell and the volume dosage of the alkali solution are in a ratio of 1.5-4.5 g:2-50 ml; and / or The mass dosage of the nanofibers and the volume dosage of the sodium hydroxide alcohol solution of the triazine compound are in a ratio of 2-3 g:7-40 ml.

7. The method according to any one of claims 1-6, characterized in that: Step (1) is specifically: First, the lotus pod shell is crushed into tuber granules with a particle size of 0.5-2 cm, then washed 1-10 times with pure water, separated by suction filtration, and dried in a vacuum drying oven at 40-80 °C for 6-24 h to obtain the pretreated lotus pod shell; Step (2) specifically is: impregnate the pretreated lotus seedpod shells in an alkali solution, react in an autoclave or a high-pressure reactor at 100 - 180 °C and a pressure of 1 - 2 MPa for 20 - 60 h, and perform solid-liquid separation by suction filtration; bleach with a 20 wt.% - 40 wt.% hydrogen peroxide solution, wash with pure water until neutral, and obtain nanofiber filaments after suction filtration separation.

8. A lotus seedpod shell fiber separator loaded with a triazine framework prepared by the method according to any one of claims 1 - 7.

9. The triazine framework-loaded lotus pod shell fiber separator according to claim 8, characterized in that: For the lotus seedpod shell fiber separator loaded with a triazine framework, as proved by contact angle measurement, the time taken for the contact angle to recover to 0° does not exceed 150 ms; and / or The bending test angle of the lotus seedpod shell fiber separator loaded with a triazine framework is not less than 120°.

10. The lotus pod shell fiber diaphragm loaded with a triazine framework according to claim 9, characterized in that: For the lotus seedpod shell fiber separator loaded with a triazine framework, as proved by contact angle measurement, the time taken for the contact angle to recover to 0° does not exceed 120 ms; and / or The bending test angle of the lotus seedpod shell fiber separator loaded with a triazine framework is not less than 180°.

11. The triazine framework-loaded lotus pod shell fiber separator according to claim 10, wherein: For the lotus seedpod shell fiber separator loaded with a triazine framework, as proved by contact angle measurement, the time taken for the contact angle to recover to 0° does not exceed 100 ms; and / or The bending test angle of the lotus seedpod shell fiber separator loaded with a triazine framework is not less than 240°.

12. The triazine framework-loaded lotus pod shell fiber diaphragm according to any one of claims 8-11, characterized in that: The thickness of the lotus seedpod shell fiber separator loaded with a triazine framework is not higher than 50 μm; and / or For the lotus seedpod shell fiber separator loaded with a triazine framework, as proved by electrochemical measurement, the electrochemical impedance of the lotus seedpod shell fiber separator does not exceed 300 Ω; and / or The ionic conductivity of the triazine framework-loaded lotus seedpod fiber membrane is not less than 18 μS·cm –1 .

13. The triazine framework-loaded lotus pod shell fiber diaphragm according to claim 12, characterized in that: The thickness of the lotus seedpod shell fiber separator loaded with a triazine framework is not higher than 40 μm; and / or For the lotus seedpod shell fiber separator loaded with a triazine framework, as proved by electrochemical measurement, the electrochemical impedance of the lotus seedpod shell fiber separator does not exceed 200 Ω; and / or The ionic conductivity of the triazine framework-loaded lotus pod shell fiber membrane is not less than 20 μS·cm –1 .

14. The triazine framework-loaded lotus pod shell fiber separator according to claim 13, characterized in that: The thickness of the lotus seedpod shell fiber separator loaded with a triazine framework is not higher than 30 μm; and / or For the lotus seedpod shell fiber separator loaded with a triazine framework, as proved by electrochemical measurement, the electrochemical impedance of the lotus seedpod shell fiber separator does not exceed 150 Ω; and / or The ionic conductivity of the triazine framework-loaded lotus pod shell fiber separator is not less than 22 μS·cm –1 .

15. Use of the lotus pod shell fiber diaphragm loaded with triazine framework prepared by the method according to any one of claims 1-7, characterized in that: Use the lotus seedpod shell fiber separator loaded with a triazine framework as the anode and cathode separators of a zinc-ion hybrid supercapacitor.

16. A zinc ion hybrid supercapacitor, characterized in that: Assemble the lotus seedpod shell fiber separator loaded with a triazine framework prepared by the method according to any one of claims 1 - 7 in the order of "zinc sheet anode - separator - carbon cathode", dropwise add an electrolyte, and obtain a zinc-ion hybrid supercapacitor after standing, drying, and encapsulation.

17. The zinc ion hybrid supercapacitor according to claim 16, characterized in that: The electrolyte in the zinc-ion hybrid supercapacitor is one or more of aqueous ZnSO4, aqueous Zn(CF3SO3)2, and aqueous ZnCl2; and / or The zinc ion hybrid supercapacitor, at a current density of 0.2 A·g -1 , has a specific capacitance storage performance of not less than 100 mA·h·g -1 ; The zinc ion hybrid supercapacitor, at a current density of 5 A·g -1 , after 5000 cycles of cyclic testing, its cyclic stability performance is not less than 85%; For the zinc-ion hybrid supercapacitor, after 5000 cycles of charge and discharge, the growth amount of dendritic by-products at the zinc anode end does not exceed 25% of the original mass of the zinc sheet.

18. The zinc ion hybrid supercapacitor according to claim 17, characterized in that: The electrolyte in the zinc-ion hybrid supercapacitor is aqueous ZnSO4 or aqueous Zn(CF3SO3)2; and / or The zinc ion hybrid supercapacitor, at a current density of 0.2 A·g -1 , has a specific capacitance storage performance of not less than 105 mA·h·g -1 ; The zinc ion hybrid supercapacitor, at a current density of 5 A·g -1 , after 5000 cycles of cyclic testing, has a cyclic stability performance of not less than 88%; For the zinc-ion hybrid supercapacitor, after 5000 cycles of charge and discharge, the growth amount of dendritic by-products at the zinc anode end does not exceed 20% of the original mass of the zinc sheet.

19. The zinc ion hybrid supercapacitor according to claim 18, characterized in that: The electrolyte in the zinc-ion hybrid supercapacitor is aqueous ZnSO4; and / or The zinc ion hybrid supercapacitor has a specific capacitance storage performance of not less than 110 mA·h·g -1 at a current density of 0.2 A·g -1 ; The zinc-ion hybrid supercapacitor, at a current density of 5 A·g -1 , after 5000 cycles of cyclic testing, has a cyclic stability performance of not less than 90%; In the zinc-ion hybrid supercapacitor, after 5000 cycles of charge and discharge, the growth amount of dendritic by-products at the zinc positive electrode end does not exceed 15% of the original mass of the zinc sheet.

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