A nitrogen / sulfur doped electrode material and its preparation method and application

Abstract

A nitrogen / sulfur-doped electrode material, a preparation method thereof and an application thereof, belong to the technical field of carbon electrode material preparation. The technical problem to be solved by the present invention is to prepare carbon material using cashew nut shells. The present invention grinds, crushes and sieves cashew nut shells, collects samples with a particle size of ≤500 μm and mixes them with an acid solution, irradiates the mixture with microwaves for 10-50 seconds, obtains a pretreated sample, places it in a high-temperature reactor, performs a carbonization activation reaction under a nitrogen atmosphere, obtains an activated product, adds ammonium thiosulfate solution, and then ultrasonically stirs for 0.5-1 hours at 30-50°C to obtain a mixture, places it in an oven at 60-100°C to evaporate water, obtains an evaporated product, performs a high-temperature reaction under a nitrogen atmosphere, obtains a reaction product, cools it to room temperature, washes it with distilled water, until the pH value is between 6-7, and is placed in an oven to dry after washing. The present invention is used for supercapacitor materials.

Description

Technical Field

[0001] The invention belongs to the technical field of carbon electrode material preparation, and specifically relates to a nitrogen / sulfur doped electrode material, a preparation method and an application thereof. Background Art

[0002] Supercapacitors (SCs) are attractive electrochemical energy storage devices that can store and deliver energy at high power and current density and exhibit high cycle life. The charge storage mechanism of SCs is divided into electrical double layer (EDL) and pseudocapacitance. The double layer is formed by the electrostatic interaction between ions and polarized electrodes on electrodes with opposite charges. The key components of SCs are electrode materials and electrolytes. The interaction of ions at the electrode / electrolyte interface in the EDL phenomenon is essential for efficient charging and discharging. In order to maximize the charge storage density of SCs, the electrode materials need to have a large specific surface area and a highly porous surface. Among the energy storage materials that have been used, carbon-based materials have attracted widespread attention due to their high specific surface area, hierarchical porous skeleton and good structural stability.

[0003] The capacitive performance of an electrode depends not only on the surface area, but also on the conductivity and surface functionality of the pore structure. Activated carbon with micropores has a high ion transport resistance, and ions are difficult to diffuse in the tortuous micropores. In graded porous carbon materials (macropores or a combination of micropores and mesopores), macropores can be used as ion buffers and liquid storage inside the carbon material. Abundant micropores and mesopores can give the electrode a high surface area, thereby enhancing the double-layer capacitance and producing high energy density. In order to expand its scope of application, people have adopted a variety of strategies to fine-tune the physical and chemical properties of these carbon materials. Among them, the most direct way to improve material performance is to adjust the pore structure through physical or chemical activation, and the performance can be improved by surface modification methods such as adding heteroatoms.

[0004] The current research direction is to research high-performance, alternative and environmentally friendly materials. Renewable carbon materials from crops or animals as supercapacitor electrode materials are an effective way to solve agricultural problems or treat domestic waste, and can reduce pollution to the atmosphere. Summary of the invention

[0005] The present invention aims to provide a nitrogen / sulfur doped electrode material prepared by using cashew nut shell, a preparation method thereof and an application thereof.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for preparing a nitrogen / sulfur doped electrode material comprises the following steps:

[0008] Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside;

[0009] Step 2, mixing the sample obtained in step 1 with the acid solution, and subjecting the mixture to microwave radiation for 10-50 seconds to obtain a pretreated sample for standby use;

[0010] Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use;

[0011] Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then stirring with ultrasound at 30-50° C. for 0.5-1 hour to obtain a mixture for standby use;

[0012] Step 5, placing the mixture obtained in step 4 in an oven at 60-100° C. to evaporate water to obtain an evaporated product for standby use;

[0013] Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use;

[0014] Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 6 and 7. After washing, dry it in an oven for 12 to 24 hours to obtain a nitrogen / sulfur-doped electrode material.

[0015] In the method for preparing a nitrogen / sulfur-doped electrode material described in the present invention, the sample in step 2 is mixed with an acid solution in a mass ratio of 1:2-3, the concentration of the acid solution is 10-30wt%, and the acid is one of phosphoric acid, sulfuric acid, hydrochloric acid, citric acid, and oxalic acid.

[0016] In the method for preparing a nitrogen / sulfur-doped electrode material described in the present invention, the carbonization activation temperature in step 3 is 300-450°C.

[0017] In the method for preparing a nitrogen / sulfur-doped electrode material described in the present invention, the concentration of the ammonium thiosulfate solution in step 4 is 10-20wt%, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:1-3.

[0018] In the method for preparing a nitrogen / sulfur-doped electrode material described in the present invention, the evaporation time in the oven in step 5 is 5-12 hours.

[0019] In the method for preparing a nitrogen / sulfur-doped electrode material described in the present invention, the heating rate in the furnace during the high-temperature reaction in step 6 is 10°C / min, the reaction process is to react at 300-500°C for 1-2h, and then increase the temperature to 600-800°C for 1-2 hours.

[0020] In the method for preparing a nitrogen / sulfur-doped electrode material described in the present invention, the oven drying temperature in step 7 is 80-105°C.

[0021] The method for preparing a nitrogen / sulfur-doped electrode material described in the present invention prepares a nitrogen / sulfur-doped electrode material, and the material has a specific capacitance of up to 214F / g.

[0022] The application of the nitrogen / sulfur doped electrode material described in the present invention is used in the field of supercapacitor electrode materials.

[0023] The method for preparing a nitrogen / sulfur-doped electrode material described in the present invention is that the cashew nut shell is not only very hard, but also has a certain degree of corrosiveness (weak toxicity), but contains a large amount of cardanol, so the cashew nut shell can be used as a renewable biomass material to prepare carbon materials.

[0024] The method for preparing a nitrogen / sulfur-doped electrode material of the present invention uses cashew nut shell as raw material and adopts a unique combination of microwave pretreatment, activation and doping technology to prepare sulfur-doped porous carbon material for supercapacitors.

[0025] The method for preparing a nitrogen / sulfur-doped electrode material according to the present invention has the following beneficial effects:

[0026] ① Reuse of crop byproducts. The source of materials is cheap and extensive, which is suitable for reducing the cost of carbon materials;

[0027] ② It solves the problem that cashew nut shells cannot be effectively utilized and avoids environmental pollution caused by direct incineration;

[0028] ③The preparation process is green and safe, without any pollution to the environment;

[0029] ④The prepared porous carbon materials can be used as supercapacitor electrode materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a SEM photo of the nitrogen / sulfur-doped electrode material prepared by the method of the first specific implementation method;

[0031] Figure 2 This is a SEM photo of the nitrogen / sulfur-doped electrode material prepared by the method of the first specific implementation method;

[0032] Figure 3 Cyclic voltammetry curves of nitrogen / sulfur-doped electrode materials at different scanning speeds prepared by the method of the first embodiment;

[0033] Figure 4 The constant current charge-discharge curves of the nitrogen / sulfur-doped electrode material prepared by the method of the first embodiment at different current densities;

[0034] Figure 5 The specific capacitance curve and voltage drop curve at different current densities of a nitrogen / sulfur-doped electrode material prepared by a method of a specific implementation method are shown. DETAILED DESCRIPTION Specific implementation method one:

[0036] A method for preparing a nitrogen / sulfur doped electrode material comprises the following steps:

[0037] Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside;

[0038] Step 2, mixing the sample obtained in step 1 with a phosphoric acid solution, and subjecting the mixture to microwave radiation for 20 seconds to obtain a pretreated sample for standby use;

[0039] Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use;

[0040] Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then stirring with ultrasound at 30° C. for 1 hour to obtain a mixture for standby use;

[0041] Step 5, placing the mixture obtained in step 4 in an oven at 80°C to evaporate water to obtain an evaporated product for standby use;

[0042] Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use;

[0043] Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 7, and then dry it in an oven for 12 hours to obtain a nitrogen / sulfur-doped electrode material.

[0044] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the sample in step 2 is mixed with a phosphoric acid solution in a mass ratio of 1:2, and the concentration of the phosphoric acid solution is 10 wt %.

[0045] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the carbonization activation temperature in step 3 is 450°C.

[0046] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the concentration of the ammonium thiosulfate solution in step 4 is 10 wt %, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:1.

[0047] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the evaporation time in the oven in step 5 is 5-12 hours.

[0048] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the heating rate in the furnace during the high-temperature reaction in step 6 is 10°C / min, and the reaction process is to react at 400°C for 1 hour, and then increase the temperature to 800°C for 2 hours.

[0049] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the oven drying temperature in step 7 is 80°C.

[0050] The nitrogen / sulfur-doped electrode material prepared by the method for preparing the nitrogen / sulfur-doped electrode material described in this embodiment is subjected to SEM testing to obtain a photograph as shown below: Figure 1 and Figure 2 As shown, the SEM image shows that pit shapes, macropores and wider mesopores can be seen on the surface of the material. Analysis shows that the surface of the material is slightly pitted, which may be caused by the heteroatom doping process. The introduction of N and S atoms may provide more active centers, which will participate in the electrochemical reactions during the charge and discharge process.

[0051] The method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment prepares a nitrogen / sulfur-doped electrode material, and a mixture of the nitrogen / sulfur-doped electrode material, carbon black and polyvinylidene fluoride (PVDF) is used to prepare a supercapacitor electrode. PVDF and carbon black are used as adhesives and conductive agents. The electrode mixture consists of 85% of the nitrogen / sulfur-doped electrode material, 10% of carbon black and 5% of PVDF (by weight). The CV curve of the electrode prepared from the nitrogen / sulfur-doped electrode material at a high scan rate is as follows: Figure 3 As shown, from Figure 3 The CV curves of the nitrogen / sulfur doped electrode material do not show obvious shape deformation, indicating that it has good capacitive behavior at high scan rates. Figure 4 As shown, at a current density of 1.0A / g, the specific capacitance provided by the nitrogen / sulfur-doped electrode material is as high as 201F / g. The GCD curves of the nitrogen / sulfur-doped electrode material at different current densities show similar triangles, and the IR drop can be ignored. At current densities of 0.5 and 2.0A / g, the specific capacitance of the nitrogen / sulfur-doped electrode material is 214F / g and 185F / g, respectively. The specific capacitance curves and voltage drop curves of the nitrogen / sulfur-doped electrode material at different current densities are shown in Figure 1. Figure 5 As shown, from Figure 5The comparison of IR drop values ​​and corresponding Cs at different current densities can be seen. Even at high current density (5.0 A / g), an IR drop of only 65 mV was observed, and the specific capacitance was 162 F / g, indicating good electrical performance. Specific implementation method 2:

[0053] A method for preparing a nitrogen / sulfur doped electrode material comprises the following steps:

[0054] Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside;

[0055] Step 2, mixing the sample obtained in step 1 with a sulfuric acid solution, and subjecting the mixture to microwave radiation for 30 seconds to obtain a pretreated sample for standby use;

[0056] Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use;

[0057] Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then ultrasonically stirring at 40° C. for 0.5 hour to obtain a mixture for standby use;

[0058] Step 5, placing the mixture obtained in step 4 in an oven at 100° C. to evaporate water to obtain an evaporated product for standby use;

[0059] Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use;

[0060] Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 6, and then dry it in an oven for 12 hours to obtain a nitrogen / sulfur-doped electrode material.

[0061] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the sample in step 2 is mixed with a sulfuric acid solution in a mass ratio of 1:2, and the concentration of the sulfuric acid solution is 15wt%.

[0062] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the carbonization activation temperature in step 3 is 400°C.

[0063] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the concentration of the ammonium thiosulfate solution in step 4 is 15 wt %, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:1.

[0064] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the evaporation time in the oven in step 5 is 5 hours.

[0065] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the heating rate in the furnace during the high-temperature reaction in step 6 is 10°C / min, and the reaction process is to react at 300°C for 2 hours, and then increase the temperature to 600°C for 2 hours.

[0066] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the oven drying temperature in step 7 is 95°C.

[0067] The nitrogen / sulfur-doped electrode material prepared by the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment is used in the field of supercapacitor electrode materials, and the material has a specific capacitance of up to 200F / g. Specific implementation method three:

[0069] A method for preparing a nitrogen / sulfur doped electrode material comprises the following steps:

[0070] Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside;

[0071] Step 2, mixing the sample obtained in step 1 with a hydrochloric acid solution, and subjecting the mixture to microwave radiation for 50 seconds to obtain a pretreated sample for standby use;

[0072] Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use;

[0073] Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then stirring ultrasonically at 50° C. for 0.5 hour to obtain a mixture for standby use;

[0074] Step 5, placing the mixture obtained in step 4 in an oven at 60°C to evaporate water to obtain an evaporated product for standby use;

[0075] Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use;

[0076] Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 6, and then dry it in an oven for 15 hours to obtain a nitrogen / sulfur-doped electrode material.

[0077] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the sample in step 2 is mixed with a hydrochloric acid solution in a mass ratio of 1:3, and the concentration of the hydrochloric acid solution is 10 wt %.

[0078] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the carbonization activation temperature in step 3 is 350°C.

[0079] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the concentration of the ammonium thiosulfate solution in step 4 is 20wt%, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:1.

[0080] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the evaporation time in the oven in step 5 is 12 hours.

[0081] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the heating rate in the furnace during the high-temperature reaction in step 6 is 10°C / min, and the reaction process is to react at 500°C for 1 hour, then raise the temperature to 700°C and react for 1.5 hours.

[0082] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the oven drying temperature in step 7 is 90°C.

[0083] The nitrogen / sulfur-doped electrode material prepared by the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment is used in the field of supercapacitor electrode materials, and the material has a specific capacitance of up to 205F / g. Specific implementation method four:

[0085] A method for preparing a nitrogen / sulfur doped electrode material comprises the following steps:

[0086] Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside;

[0087] Step 2, mixing the sample obtained in step 1 with a citric acid solution, and subjecting the mixture to microwave radiation for 10 seconds to obtain a pretreated sample for standby use;

[0088] Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use;

[0089] Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then stirring ultrasonically at 40° C. for 0.8 hours to obtain a mixture for standby use;

[0090] Step 5, placing the mixture obtained in step 4 in an oven at 90°C to evaporate water to obtain an evaporated product for standby use;

[0091] Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use;

[0092] Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 7, and then dry it in an oven for 12 hours to obtain a nitrogen / sulfur-doped electrode material.

[0093] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the sample in step 2 is mixed with a citric acid solution in a mass ratio of 1:2, and the concentration of the citric acid solution is 20 wt %.

[0094] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the carbonization activation temperature in step 3 is 450°C.

[0095] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the concentration of the ammonium thiosulfate solution in step 4 is 10 wt %, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:3.

[0096] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the evaporation time in the oven in step 5 is 10 hours.

[0097] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the heating rate in the furnace during the high-temperature reaction in step 6 is 10°C / min, and the reaction process is to react at 400°C for 2 hours and then increase the temperature to 700°C for 1 hour.

[0098] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the oven drying temperature in step 7 is 95°C.

[0099] The nitrogen / sulfur-doped electrode material prepared by the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment is used in the field of supercapacitor electrode materials, and the material has a specific capacitance of up to 202F / g. Specific implementation method five:

[0101] A method for preparing a nitrogen / sulfur doped electrode material comprises the following steps:

[0102] Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside;

[0103] Step 2, mixing the sample obtained in step 1 with the oxalic acid solution, and subjecting the mixture to microwave radiation for 10-50 seconds to obtain a pretreated sample for standby use;

[0104] Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use;

[0105] Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then stirring ultrasonically at 30° C. for 0.5 hour to obtain a mixture for standby use;

[0106] Step 5, placing the mixture obtained in step 4 in an oven at 60°C to evaporate water to obtain an evaporated product for standby use;

[0107] Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use;

[0108] Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 6, and then dry it in an oven for 12 hours to obtain a nitrogen / sulfur-doped electrode material.

[0109] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the sample in step 2 is mixed with the oxalic acid solution in a mass ratio of 1:2, and the concentration of the oxalic acid solution is 10 wt %.

[0110] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the carbonization activation temperature in step 3 is 300°C.

[0111] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the concentration of the ammonium thiosulfate solution in step 4 is 10 wt %, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:1.

[0112] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the evaporation time in the oven in step 5 is 8 hours.

[0113] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the heating rate in the furnace during the high-temperature reaction in step 6 is 10°C / min, and the reaction process is to react at 300°C for 1 hour, and then increase the temperature to 600°C for 1 hour.

[0114] In the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment, the oven drying temperature in step 7 is 80°C.

[0115] The nitrogen / sulfur-doped electrode material prepared by the method for preparing a nitrogen / sulfur-doped electrode material described in this embodiment is used in the field of supercapacitor electrode materials, and the material has a specific capacitance of up to 190F / g.

Claims

1. A method for preparing a nitrogen / sulfur doped electrode material, characterized in that: The steps include: Step 1, grinding, crushing and sieving the cashew nut shells, collecting samples with a particle size of ≤500 μm and setting aside; Step 2, mixing the sample obtained in step 1 with the acid solution, and subjecting the mixture to microwave radiation for 10-50 seconds to obtain a pretreated sample for standby use; The sample in step 2 is mixed with an acid solution in a mass ratio of 1:2-3, the concentration of the acid solution is 10-30wt%, and the acid is one of phosphoric acid, sulfuric acid, hydrochloric acid, citric acid, and oxalic acid; Step 3, placing the pretreated sample obtained in step 2 in a high-temperature reaction furnace, and performing a carbonization activation reaction under a nitrogen atmosphere to obtain an activated product for standby use; The carbonization activation temperature in step 3 is 300-450°C; Step 4, adding ammonium thiosulfate solution to the activated product obtained in step 3, and then stirring with ultrasound at 30-50° C. for 0.5-1 hour to obtain a mixture for standby use; The concentration of the ammonium thiosulfate solution in step 4 is 10-20wt%, and the mass ratio of the activated product to the ammonium thiosulfate solution is 1:1-3; Step 5, placing the mixture obtained in step 4 in an oven at 60-100° C. to evaporate water to obtain an evaporated product for standby use; The evaporation time in the oven in step 5 is 5-12 hours; Step 6, subjecting the evaporated product obtained in step 5 to a high temperature reaction under a nitrogen atmosphere to obtain a reaction product, cooling it to room temperature for standby use; In step 6, the heating rate in the furnace during the high temperature reaction is 10°C / min, and the reaction process is to react at 300-500°C for 1-2h, and then increase the temperature to 600-800°C for 1-2h; Step 7: Wash the reaction product obtained in step 6 with distilled water until the pH value is between 6 and 7. After washing, dry it in an oven for 12 to 24 hours to obtain a nitrogen / sulfur-doped electrode material.

2. The method for preparing a nitrogen / sulfur doped electrode material according to claim 1, characterized in that: In step 7, the oven drying temperature is 80-105°C.

3. A nitrogen / sulfur-doped electrode material prepared by the method for preparing a nitrogen / sulfur-doped electrode material according to any one of claims 1 to 2, characterized in that: The material's specific capacitance reaches up to 214F / g.

4. An application of a nitrogen / sulfur doped electrode material according to claim 3, characterized in that: Used in the field of supercapacitor electrode materials.

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