Preparation method of hcp-Ru-coated NiCoMn / RG core-shell catalyst for promoting metal Ru to reconstruct fcc-NiCoMn alloy particle crystal skeleton based on Joule thermal shock

Abstract

The invention discloses a preparation method of an hcp-Ru-NiCoMn / RG core-shell catalyst for promoting metal Ru to reconstruct an fcc-NiCoMn alloy particle crystal skeleton based on Joule thermal shock, and belongs to the technical field of waste ternary lithium battery recycling. Fcc-NiCoMn / RG serves as a precursor of the catalyst, Ru atoms are introduced, under Joule thermal shock, the fcc structure of NiCoMn alloy particles is changed, the NiCoMn alloy particles are fully alloyed with a surface Ru layer, and the surface Ru layer is formed; and the Ru-coated NiCoMn alloy particles with the hcp structure are formed. Due to the formation of the core-shell structure, active sites on the surface of the catalyst are fully exposed, the catalytic efficiency on ORR and OER processes is greatly improved, and meanwhile, the structural stability of the catalyst is ensured in the reaction process by virtue of a stable hcp alloy structure on the surface and firm d-d orbital coupling between metals. The alloying of the Ru and the transition metal enables the Ru to capture electrons from the transition metal to fill a reverse bond energy band, so that the center of a d band moves downwards relative to the Fermi level, the adsorption and desorption energy barrier of an oxygen-containing intermediate in the reaction process is optimized, and the electrochemical performance of the lithium-oxygen battery is effectively improved by the catalyst.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of recycling and utilization of waste ternary lithium batteries, and particularly relates to a preparation method of an hcp-Ru@NiCoMn / RG core-shell catalyst based on joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeletons by metal Ru. BACKGROUND

[0002] Traditional lithium ion batteries are limited by the lithium storage capacity of positive and negative materials, and the theoretical energy density has obvious bottlenecks. Lithium-air batteries do not need to carry heavy inherent positive electrodes in the battery, and use oxygen in the air as the positive active material, so that the theoretical energy density can reach more than 3500 Wh / kg, far exceeding traditional lithium ion batteries, and becoming a very potential energy storage device.

[0003] The discharge product lithium peroxide of the lithium-oxygen battery has poor conductivity and is difficult to decompose. If a large amount of lithium peroxide is generated and nucleated and grown, the electrode will be blocked, the efficiency of electron transmission and mass transfer will be affected, and the capacity of the lithium-oxygen battery will be greatly reduced and the polarization will be increased. In the charging and discharging reaction process of the lithium-oxygen battery, superoxide, singlet oxygen and some oxygen-containing intermediates will cause the decomposition of the electrolyte and the positive carbon material, and generate lithium carbonate and other by-products, further deepening the polarization problem, passivating the positive electrode, and making the battery lose the ability to work. This is an important reason why the lithium-oxygen battery has poor cycle stability.

[0004] In order to solve the above technical problems existing in the lithium-oxygen battery and release its super-high application potential, the existing researches mostly adopt the way of adding a positive catalyst to process. The positive catalyst of the lithium-oxygen battery can efficiently induce the nucleation and growth mechanism of the discharge product lithium peroxide, control the nucleation site and growth mode thereof in the discharging process, and efficiently decompose in the charging process. The positive catalyst can control the adsorption and desorption energy barrier of the oxygen-containing intermediate, improve the chemical reaction kinetics in the charging and discharging process, avoid the enrichment of singlet oxygen and other oxygen-containing intermediates, reduce the generation of by-products, and improve the cycle life of the lithium-oxygen battery.

[0005] Therefore, it is of great significance to design an hcp-Ru@NiCoMn / RG core-shell catalyst based on the recycling of waste ternary lithium batteries and taking a step-by-step joule heat shock method to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeletons by metal Ru. SUMMARY

[0006] The application discloses a preparation method of an hcp-Ru@NiCoMn / RG core-shell catalyst based on joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeleton by metal Ru, the catalyst taking the fcc-NiCoMn / RG as a precursor, introducing Ru atoms, changing the fcc structure of the NiCoMn alloy particle under the joule heat shock, and making the fcc structure fully alloyed with the surface Ru layer to become the hcp structure Ru@NiCoMn alloy particle. The formation of the core-shell structure not only fully exposes the active sites on the surface of the catalyst, greatly improves the catalytic efficiency of the ORR and OER processes, but also ensures the structural stability of the catalyst in the reaction process due to the stable hcp alloy structure on the surface and the firm d-d orbital coupling between the metals. The alloying of Ru and the transition metal captures the electrons of the transition metal to fill the antibonding band, makes the d-band center move downward relative to the Fermi level, and optimizes the adsorption and desorption energy barrier of the oxygen-containing intermediate in the reaction process. The catalyst is applied to a lithium-oxygen battery, and effectively improves the electrochemical performance of the lithium-oxygen battery.

[0007] To achieve the above object, the technical scheme of the application is: The preparation method of the hcp-Ru@NiCoMn / RG core-shell catalyst based on joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeleton by metal Ru, comprising the following steps: S1: recovering a NiCoMn ion solution and graphene from waste ternary lithium battery positive and negative electrodes; S2: preparing an fcc-NiCoMn / RG precursor; S3: preparing an hcp-Ru@NiCoMn / RG core-shell catalyst.

[0008] Preferably, the step S1 comprises the following specific steps: (1) cutting the waste ternary lithium battery positive electrode into small pieces, placing the small pieces in an N-methyl pyrrolidone (NMP) solution for ultrasonic treatment for 10 hours, centrifuging and drying the obtained turbid solution to obtain positive electrode black powder; dissolving 0.5 g of the positive electrode black powder in 40 mL of a potassium carbonate solution, washing in a 90 DEG C coil bath for 3 hours, and then centrifuging to obtain a Ni, Co and Mn-containing precipitate; adding 0.5 g of the precipitate to 40 mL of a 1M nitric acid solution, washing at room temperature for 3 hours, centrifuging to remove the impurity solution, and then standing for 24 hours to obtain the recovered NiCoMn ion solution; (2) cutting the waste ternary lithium battery negative electrode sheet, using joule heat shock to heat to 800 DEG C for 5-10 seconds, keeping the temperature for 5-10 seconds, carbonizing the binder, and collecting the fallen negative electrode black powder; performing a second joule heat shock on the negative electrode black powder, heating to 1800 DEG C for 5-10 seconds, igniting the interlayer Li +The van der Waals force between the graphite layers is destroyed at the invisible site to obtain a graphene powder containing impurities; the obtained powder is subjected to acid washing with 5M hydrochloric acid, washed to remove other impurities, cleaned with deionized water, centrifuged, and vacuum dried at 60℃ for 24h to obtain a graphene powder without impurities, i.e., carrier recycled graphene RG.

[0009] Preferably, the step S2 comprises the following specific steps: 100mg of graphene powder is dissolved in 0.16mL of NiCoMn ion solution in 30mL of anhydrous ethanol, heated in an 85℃ oil bath with 200r / min stirring until dry, to obtain powder A; the powder A is subjected to joule heat shock, heated to 900℃ for 5-10s and then kept for 5-10s, and then naturally cooled to room temperature to obtain the fcc-NiCoMn / RG precursor powder.

[0010] Preferably, the step S3 comprises the following specific steps: 50mg of fcc-NiCoMn / RG precursor powder and 0.2mL of Ru metal salt solution are dissolved in 30mL of anhydrous ethanol, heated in an 85℃ oil bath with 200r / min stirring until dry, to obtain powder B; the powder B is subjected to joule heat shock, heated to 1500℃ for 5-10s and then kept for 10-15s, and then naturally cooled to room temperature to obtain the hcp-Ru@NiCoMn / RG core-shell catalyst.

[0011] Preferably, in the step S3, the Ru metal salt solution is RuCl3 solution.

[0012] The beneficial effects of the preparation method of the hcp-Ru@NiCoMn / RG core-shell catalyst based on joule heat shock to promote the metal Ru to reconstitute the fcc-NiCoMn alloy particle crystal skeleton are: (1) The advantage of recycling the positive and negative electrode materials of the waste ternary lithium battery: the waste ternary lithium battery is rich in valuable transition metals Ni, Co, Mn, etc. in the positive electrode, and if it is randomly leaked into the natural environment, it will cause persistent pollution to water sources and soil, and the negative electrode graphite may also cause dust pollution. Through the recycling method, not only can the environmental pollution risk be blocked at the source, but also the valuable Ni, Co, Mn metal ions in the positive electrode and the negative electrode graphite resources can be efficiently recycled, and the recycling process realizes the dual protection of high recovery rate and high purity, so that the waste battery resources are fully regenerated and utilized, and the resource potential is maximized.

[0013] (2) Process advantages of joule heat shock: The conventional tube furnace annealing and other high-temperature treatment methods have the problems of long heating time, excessive growth of particles, and uneven distribution. The instantaneous impact characteristics of joule heat shock can complete the required energy supply of metal alloying in a short time, preventing excessive growth of metal and intermetallic sintering during long-time heating. The core-shell structure formed in this patent requires Ru to be adsorbed on the surface of the NiCoMn alloy particles efficiently, uniformly loaded to form a Ru layer on the surface, and the strong high-temperature driving effect of joule heat shock on metal particles effectively realizes the rapid displacement and orderly arrangement of atoms, fully stimulating the structural advantages of hcp-Ru@NiCoMn / RG.

[0014] (3) Recycling process advantage of energy filling through invisible site explosion Li + The traditional preparation scheme of graphene often uses concentrated acid to participate in the reaction to release super-high energy to destroy the interlayer van der Waals force of the graphite structure to obtain a graphene sheet structure, usually with problems such as violent reaction, large amount of reagent, and large amount of reaction residual waste; if the instantaneous super-high temperature of joule heat shock is directly used to provide energy to destroy the interlayer van der Waals force, it needs to be heated to a high temperature of about 3000℃ in a very short time, which requires a high temperature and large energy consumption. In this scheme, the precursor graphite used to prepare graphene comes from the negative electrode recycling of waste ternary lithium batteries. Due to the charging and discharging behavior of ternary lithium batteries, Li + is distributed in the interlayer position of the graphite sheet structure of the negative electrode of the waste ternary lithium battery after discharge pretreatment. + , and there are also a large amount of Li + distributed in the interlayer position of the graphite sheet structure of the negative electrode. Taking advantage of this feature, the negative electrode recycled graphite is directly subjected to joule heat shock, and the Li + distributed in the interlayer of the graphite is used as an invisible explosion site. At a temperature of 1800℃, the chemically active Li + will produce a violent electron release behavior, and at the same time, it will sublimate to produce a small amount of gas. Under the disturbance of the electron activity to the van der Waals force and the expansion of the Li + sublimation gas, it is no longer difficult to destroy the interlayer van der Waals force of graphite. The temperature required for joule heat shock is greatly reduced, and only 1800℃ is needed to break the van der Waals force between the graphite layers, obtaining a large amount of single-layer graphene structure.

[0015] (4) The innovative breakthrough of Ru pulling the reconstruction of fcc-NiCoMn alloy crystal skeleton: In this scheme, the fcc-NiCoMn / RG precursor is prepared by the first joule heating impact, which traps the disordered NiCoMn ions in ultra-small nanoparticles to form fcc-NiCoMn alloy particles distributed on the single-layer graphene sheet. The uniform distribution of ultra-fine NiCoMn alloy particles provides abundant adsorption sites for Ru, and the instantaneous high temperature of joule heating impact promotes the Ru atoms to be uniformly distributed on the surface of the NiCoMn alloy particles. The second time with Ru metal salt solution as the Ru source, the Ru atoms are adsorbed on the surface of the NiCoMn alloy particles with equal molar ratio, and the second joule heating impact promotes the complete alloying of the metal components. The addition of hcp phase Ru changes the electronic structure of fcc phase NiCoMn, causing the migration of NiCoMn atoms, and reconstructing the crystal skeleton from fcc phase to hcp phase, forming a single-phase structure of hcp-Ru@NiCoMn with Ru, greatly enhancing the stability of the alloy particles.

[0016] (5) The advantages of core-shell structure alloy particles: The second joule heating impact makes Ru fully contact with the NiCoMn alloy sites on the surface of graphene to form a Ru layer. The formation of the Ru layer reshapes the electronic structure of the NiCoMn alloy particles, causing the displacement of atoms in the fcc phase of the NiCoMn alloy, and the complete transformation of the fcc-NiCoMn alloy particles into hcp-Ru@NiCoMn. The core-shell structure formed can maximize the use of space, effectively limit the size of the alloy particles, improve the density and stability of the material, and better expose the catalytic active sites of hcp-Ru@NiCoMn, which is applied to lithium-oxygen batteries to achieve stable performance improvement. The stable interface contact between the Ru layer and the NiCoMn alloy particles through alloying is beneficial to the efficient transport of electrons, improving the redox reaction kinetics, and the stable hexagonal close-packed structure makes Ru a good protective layer during the reaction process, ensuring that the hcp-Ru@NiCoMn / RG catalyst has good process stability.

[0017] (6) d band center regulation advantage: the d band center of metal atoms is directly related to the adsorption strength of adsorbate, and by regulating the d band, the reaction activity and selectivity of the catalyst can be optimized. After Ru is alloyed with the NiCoMn in the precursor, electrons are captured from the transition metal with lower electronegativity, filling the antibonding band itself, making the d band move down relative to the Fermi level, relieving the excessive adsorption of oxygen-containing intermediates, and reducing the desorption energy barrier. The efficient adsorption and desorption of oxygen-containing intermediates by the hcp-Ru@NiCoMn / RG promotes the efficient generation and decomposition of lithium peroxide, enhances the catalytic efficiency of ORR and OER, and effectively optimizes the electrochemical performance of lithium-oxygen batteries. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a scanning electron microscope image of a graphene-supported hcp-Ru@NiCoMn core-shell catalyst; Figure 2 is a transmission electron microscope image of a graphene-supported hcp-Ru@NiCoMn core-shell catalyst: Figure 3 is an X-ray diffraction curve of the fcc-NiCoMn / RG precursor and the graphene-supported hcp-Ru@NiCoMn core-shell catalyst; Figure 4 is a deep charge and discharge performance test curve of the graphene-supported hcp-Ru@NiCoMn core-shell catalyst; Figure 5 is a CV performance test curve of the graphene-supported hcp-Ru@NiCoMn core-shell catalyst. DETAILED DESCRIPTION

[0019] The following description is only a preferred embodiment of the present application, and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0020] The following examples can be understood as part of the expression of the partial structure or method of the present application alone, or as part of the mutual combination of the examples to explain the larger range of structure or method of the present application.

[0021] Example 1: The preparation method of the hcp-Ru@NiCoMn / RG core-shell catalyst based on Joule heat shock to promote the reconstruction of the fcc-NiCoMn alloy particle crystal skeleton by metal Ru, comprises the following steps: S1: recovering NiCoMn ion solution and graphene from waste ternary lithium battery positive and negative electrodes; S2: preparation of the fcc-NiCoMn / RG precursor; S3: Preparation of the hcp-Ru@NiCoMn / RG core-shell catalyst.

[0022] Example 2: The step S1 comprises the following specific steps: (1) The positive electrode of the waste ternary lithium battery is cut into small pieces, and is placed in an N-methyl pyrrolidone solution (NMP) for ultrasonic treatment for 10 hours. The obtained turbid solution is centrifuged and dried to obtain a positive electrode black powder. 0.5 g of the positive electrode black powder is dissolved in 40 mL of a potassium carbonate solution, and is washed in a 90°C coil bath for 3 hours. Then, the positive electrode black powder is centrifuged to obtain a precipitate containing Ni, Co and Mn. 0.5 g of the precipitate is added to 40 mL of a 1M nitric acid solution, and is washed at room temperature for 3 hours. The impurity solution is removed by centrifugation. After standing for 24 hours, the supernatant is the recovered NiCoMn ion solution; (2) The negative electrode sheet of the waste ternary lithium battery is cut and then subjected to a joule heat shock. The temperature is heated to 800°C for 5-10 seconds, and the binder is carbonized. The fallen negative electrode black powder is collected. The negative electrode black powder is subjected to a second joule heat shock. The temperature is heated to 1800°C for 5-10 seconds, and the interlayer Li + The van der Waals force between the layers of the graphite is destroyed to obtain a graphene powder containing impurities. The obtained powder is subjected to acid pickling with 5M hydrochloric acid. After the other impurities are washed away, the powder is washed with deionized water, centrifuged, and vacuum dried at 60°C for 24 hours to obtain the graphene powder without impurities, that is, the recovered graphene RG.

[0023] Example 3: The step S2 comprises the following specific steps: 100 mg of the graphene powder and 0.16 mL of the NiCoMn ion solution are dissolved in 30 mL of anhydrous ethanol. The mixture is heated in an 85°C oil bath and stirred at 200 r / min until it is evaporated to obtain powder A. The powder A is subjected to a joule heat shock. The temperature is heated to 900°C for 5-10 seconds, and then is naturally cooled to room temperature to obtain the fcc-NiCoMn / RG precursor powder.

[0024] Example 4: The step S3 comprises the following specific steps: 50 mg of the fcc-NiCoMn / RG precursor powder and 0.2 mL of a Ru metal salt solution are dissolved in 30 mL of anhydrous ethanol. The mixture is heated in an 85°C oil bath and stirred at 200 r / min until it is evaporated to obtain powder B. The powder B is subjected to a joule heat shock. The temperature is heated to 1500°C for 10-15 seconds, and then is naturally cooled to room temperature to obtain the hcp-Ru@NiCoMn / RG core-shell catalyst.

[0025] In the step S3, the Ru metal salt solution is a RuCl3 solution.

[0026] The working principle of the application is: The application recovers NiCoMn ion solution and recovers graphene (RG) from the positive and negative electrodes of waste ternary lithium batteries respectively, and finally prepares a high-efficiency catalyst of recycled graphene loaded hcp-Ru@NiCoMn hexagonal core-shell alloy particles by means of two times of joule heat shock. Ru metal salt solution is used as the Ru source, and the NiCoMn ion solution recovered from the positive electrode of the waste ternary lithium battery is used as the transition metal source. That is, the recovered graphene is used as a carrier, the first joule heat shock is used to prepare the face-centered cubic (fcc) NiCoMn alloy particle loaded precursor fcc-NiCoMn / RG, and then metal Ru is added and the second joule heat shock is performed, which reconstructs the crystal skeleton of the NiCoMn alloy particles and converts them from the face-centered cubic structure (fcc) to the hexagonal close-packed structure (hcp), thereby preparing the high-efficiency catalyst of the hexagonal core-shell alloy particles loaded on the recycled graphene, hcp-Ru@NiCoMn / RG. The catalyst is applied to a lithium-oxygen battery, and the electrochemical performance of the lithium-oxygen battery is stably improved.

[0027] In the operation process, graphene powder is recovered from the negative electrode of the waste ternary lithium battery by means of joule heat shock combined with acid washing. The joule heat shock step utilizes its instantaneous high temperature and uniform heating characteristics. After sublimation of the binder in the negative electrode at 800°C, the residual Li + The graphene powder, the NiCoMn ion solution, and the Ru salt solution are dissolved in anhydrous ethanol, heated and stirred, and evaporated to obtain a powder. After the first joule heat shock, the precursor fcc-NiCoMn / RG powder is obtained at a temperature of 900°C for 5-10s. Then the precursor powder and the Ru salt solution are dissolved in anhydrous ethanol again, heated and stirred, and evaporated to obtain a powder. After the second joule heat shock, the high-efficiency catalyst of the hexagonal core-shell alloy particles loaded on the recycled graphene, hcp-Ru@NiCoMn / RG, is obtained at a temperature of 1500°C for 10-15s. After the addition of Ru, Ru is adsorbed on the surface sites of the NiCoMn alloy particles to form a Ru layer, and the alloying process pulls and reconstructs the crystal skeleton of the NiCoMn alloy particles, which causes the original atomic sites to shift and rearrange, and the original fcc phase to transform into a composite hcp phase. Through this method, the high-efficiency catalyst hcp-Ru@NiCoMn / RG can be prepared. In the catalyst preparation process, the positive and negative electrode materials of the waste ternary lithium battery are effectively utilized, the resource utilization rate is improved, and at the same time, the waste ternary lithium battery is recycled, the waste ternary lithium battery is recycled, and the waste ternary lithium battery is recycled. Figures 1-5As shown, the two joule heat shocks distribute the load on the metal, promoting the remodeling of the Ru to the transition metal NiCoMn alloy structure, and the new structure fully exposes the catalytic sites, thereby constructing a positive electrode catalyst that can efficiently improve the electrochemical performance of lithium-oxygen batteries.

[0028] The specific innovations are as follows: 1. A method for blasting residual Li in waste ternary lithium battery negative electrode graphite using joule heat shock + The invisible site provides a new idea for preparing graphene at a lower temperature by destroying the van der Waals force between the layers of graphite. In the process of preparing graphene, traditional mechanical peeling, chemical peeling and other methods have the disadvantages of high energy consumption, low yield and difficult quality control. As a high-temperature treatment method that is currently being researched, joule heat shock also requires a high temperature of more than 3000°C to directly destroy the van der Waals force between the layers of graphite. The present scheme takes advantage of the fact that the negative electrode graphite of the discharged waste ternary lithium battery is rich in a large amount of free Li + , which is uniformly dispersed between the layers of graphite. The free Li + between the layers of graphite is used as an invisible blasting site, and only joule heat shock to 1800°C is needed to ignite the site. The violent electronic disturbance produced by Li + at high temperatures and the gas phase expansion caused by its volatilization help to weaken the van der Waals force between the layers. This reduces the high-temperature burden of direct preparation of graphene by joule heat shock and greatly reduces the required energy consumption.

[0029] 2. The valuable transition metal elements in the positive electrode of the waste ternary lithium battery are converted into a usable metal ion solution by methods such as ultrasonic, washing, coil bath, centrifugal drying, etc. Not only can it effectively reduce the environmental pollution risk caused by the random disposal of waste batteries, solve the industry pain point of insufficient resource utilization under the traditional scrap processing mode, realize the dual improvement of environmental and resource benefits, but also has the outstanding highlights of strong process adaptability, simple operation process, and excellent metal selective separation effect. It can achieve efficient separation of target metals and impurities, greatly improving product purity. In the recycling process provided in the present scheme, the reagents such as potassium carbonate solution used are conventional chemicals with mature applications in the industrial field, and have the significant advantages of controllable cost and industrialization promotion. The recycling process is highly consistent with the actual production needs of the industry, and has the advantages of advanced technology, cost-effectiveness and environmental friendliness, and has strong industrial adaptability and practical application value.

[0030] 3、In this scheme, the preparation of fcc-NiCoMn / RG precursor and the final synthesis of hcp-Ru@NiCoMn / RG core-shell catalyst are carried out by Joule heating shock. The instantaneous high temperature of Joule heating shock successfully synthesizes fcc-NiCoMn and hcp-Ru@NiCoMn ultrafine alloy particles, prevents particle growth caused by long-time heating, makes full use of the surface area of graphene, creates more catalytic sites, and improves catalytic efficiency.

[0031] 4、In this scheme, after Ru is added to the fcc-NiCoMn / RG precursor, it is adsorbed on the NiCoMn alloy site and uniformly distributed on the outer layer of the NiCoMn alloy particle. During the evolution process, it causes the displacement of disordered atoms in the NiCoMn alloy particle and rearranges its crystal skeleton, so that the fcc structure of the NiCoMn alloy particle is transformed into the hcp structure, alloyed with Ru to form hcp-Ru@NiCoMn / RG, form a core-shell structure, expose more active reaction sites, and improve catalytic efficiency. The stable hexagonal close-packed structure ensures the structural inertia of the catalyst during the electrochemical reaction process.

Claims

1. A method for preparing an hcp-Ru@NiCoMn / RG core-shell catalyst by using Joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeleton with metal Ru, comprising the following steps: S1: recovering a NiCoMn ion solution and graphene from waste ternary lithium battery positive and negative electrodes; S2: preparing an fcc-NiCoMn / RG precursor; S3: preparing an hcp-Ru@NiCoMn / RG core-shell catalyst. 2.The method for preparing an hcp-Ru@NiCoMn / RG core-shell catalyst by using Joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeleton with metal Ru according to claim 1, wherein the step S1 comprises the following specific steps: (1) cutting the waste ternary lithium battery positive electrode into small pieces, placing them in an N-methyl pyrrolidone (NMP) solution for ultrasonic treatment for 10 hours, centrifuging and drying the obtained turbid solution to obtain positive electrode black powder; dissolving 0.5 g of the positive electrode black powder in 40 mL of a potassium carbonate solution, washing in a 90°C coil bath for 3 hours, and then centrifuging to obtain a Ni, Co and Mn-containing precipitate; adding 0.5 g of the precipitate to 40 mL of a 1M nitric acid solution, washing at room temperature for 3 hours, centrifuging to remove the impurity solution, and then standing for 24 hours to obtain the recovered NiCoMn ion solution; (2) the waste ternary lithium battery negative plate is cut into pieces, and then subjected to joule heat shock, heated to 800 DEG C for 5-10s, and kept for 5-10s, so that the binder is carbonized, and the negative black powder falling off is collected; the negative black powder is subjected to second joule heat shock, heated to 1800 DEG C for 5-10s, and kept for 5-10s, so that the interlayer Li + The impurity-containing graphene powder is obtained by destroying the interlayer van der Waals force of graphite. The obtained powder is subjected to acid pickling with 5M hydrochloric acid, washed to remove other impurities, cleaned with deionized water, centrifuged, and vacuum dried at 60 DEG C for 24h to obtain the impurity-removed graphene powder, i.e., the carrier recycled graphene RG. 3.The method for preparing an hcp-Ru@NiCoMn / RG core-shell catalyst by using Joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeleton with metal Ru according to claim 2, wherein the step S2 comprises the following specific steps: dissolving 100 mg of graphene powder and 0.16 mL of the NiCoMn ion solution in 30 mL of anhydrous ethanol, heating in an 85°C oil bath with stirring at 200 r / min until evaporation to obtain powder A; performing Joule heat shock on the powder A, heating to 900°C for 5-10 seconds, then maintaining the temperature for 5-10 seconds, and then naturally cooling to room temperature to obtain the fcc-NiCoMn / RG precursor powder. 4.The method for preparing an hcp-Ru@NiCoMn / RG core-shell catalyst by using Joule heat shock to promote the reconstruction of fcc-NiCoMn alloy particle crystal skeleton with metal Ru according to claim 3, wherein the step S3 comprises the following specific steps: dissolving 50 mg of the fcc-NiCoMn / RG precursor powder and 0.2 mL of a Ru metal salt solution in 30 mL of anhydrous ethanol, heating in an 85°C oil bath with stirring at 200 r / min until evaporation to obtain powder B; performing Joule heat shock on the powder B, heating to 1500°C for 5-10 seconds, then maintaining the temperature for 10-15 seconds, and then naturally cooling to room temperature to obtain the hcp-Ru@NiCoMn / RG core-shell catalyst.

5. The method for preparing the hcp-Ru@NiCoMn / RG core-shell catalyst based on the impact of Joule heat to facilitate the reconstruction of the fcc-NiCoMn alloy particle crystal skeleton by Ru as claimed in claim 4, characterized in that, In the step S3, the Ru metal salt solution is a RuCl3 solution.

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