A carbon carrier supported recycled transition metal alloy catalyst, and a preparation method and application thereof

Abstract

This invention discloses a carbon-supported catalyst for recovering transition metal alloys, its preparation method, and its application, belonging to the technical field of waste lithium-ion battery recycling. The invention employs a deep eutectic solvent wet recovery process, successfully achieving the stepwise extraction of nickel and cobalt from waste lithium-ion battery powder using a series method. Based on this, the recovered transition metals are directly converted into an oxygen evolution reaction catalyst via electrodeposition, eliminating the need for intermediate purification steps. This catalyst exhibits excellent comprehensive electrochemical performance. The catalyst provided by this invention offers a new approach for the recycling and reuse of waste lithium-ion batteries in the field of water electrolysis, laying a solid experimental foundation for the reintroduction of electronic waste into large-scale energy storage applications, and possesses significant scientific value and application prospects.

Description

Technical Field

[0001] This invention belongs to the field of waste lithium-ion battery recycling technology, specifically relating to a carbon-supported catalyst for recycling transition metal alloys, its preparation method, and its application. Background Technology

[0002] Advances in new energy and smart living technologies have led to a surge in e-waste production, posing a serious environmental challenge. E-waste contains over 60 metals, including precious metals (such as gold (Au) and palladium (Pd)) and transition metals (such as copper (Cu), aluminum (Al), and iron (Fe),) and possesses extremely high recycling value. The high material value of certain e-waste materials (such as spent lithium-ion batteries) makes metal recycling particularly urgent. Although recycling requires capital investment, efficient recycling processes can not only alleviate raw material shortages but also create significant economic benefits. Therefore, developing efficient methods for recycling and reusing e-waste is crucial for sustainable development.

[0003] To date, significant efforts have been made to develop and utilize various clean energy sources. Against this backdrop, hydrogen (oxygen) production via electrically driven water splitting has become a feasible strategy for achieving renewable energy conversion. Numerous methods for preparing transition metal catalysts for water electrolysis have been reported. The scarcity of precious metals severely hinders their large-scale application in water electrolysis. Therefore, non-precious metal materials, including transition metal sulfides, phosphides, nitrides, oxides, and carbides, have become a hot research topic. In particular, carbon-based transition metal alloy catalysts are receiving increasing attention. It is well known that carbon materials are effective supports for stabilizing metal-based catalysts. By loading alloy catalysts onto carbon supports, charge transfer can be enhanced and catalytic reaction kinetics accelerated while reducing the amount of metal used.

[0004] Therefore, by constructing a closed-loop recycling strategy of "resource-product-recycled resources" and systematically studying the dynamic structure-property mechanism of material structure evolution and electrodeposition behavior, a solid experimental foundation is laid for the application of electronic waste in the field of large-scale energy storage, which has important scientific value and application prospects. Summary of the Invention

[0005] The purpose of this invention is to provide a carbon-supported catalyst for recovering transition metal alloys, its preparation method, and its application. Using transition metal oxalates recovered from waste lithium-ion battery coarse powder (referred to as battery black powder) as a precursor, this invention successfully prepared a carbon-supported catalyst for recovering transition metal alloys in the oxygen evolution reaction (OER) via electrodeposition. The morphology, structure, and electrochemical performance of the bimetallic alloy catalyst were comprehensively evaluated. This invention fully utilizes nickel oxalate and cobalt oxalate hydrates obtained from previous work using a deep eutectic solvent tandem leaching process, achieving a closed-loop transformation from electronic waste to high-value-added electrocatalytic materials. During catalyst synthesis, this invention only requires hydrochloric acid to adjust the pH of the electrodeposition solution, without using other additional chemical reagents, fully demonstrating the simplicity and green characteristics of this preparation route.

[0006] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a method for preparing a carbon-supported catalyst for recovering transition metal alloys, comprising the following steps: Battery black powder was soaked in dimethyl carbonate, and the separated solid material was washed, dried, and then calcined to obtain pretreated battery black powder. The pretreated battery black powder was mixed with a deep eutectic solvent (DES) composed of oxalic acid (OxA) and choline chloride (ChCl), stirred and leached, then dimethyl sulfoxide was added as a diluent, and then centrifuged. The separated precipitate was nickel oxalate. The separated solution was diluted with water and heated to precipitate cobalt oxalate. The recovered nickel oxalate and cobalt oxalate were dissolved in water and the pH was adjusted to 1-2 to obtain the electrodeposition solution; Nickel and cobalt in the electrodeposition solution are deposited onto a carbon support by electrodeposition to obtain a carbon support-supported recovery transition metal alloy catalyst.

[0007] Preferably, the soaking temperature is 80°C and the soaking time is 1 hour.

[0008] Preferably, the calcination temperature is 900℃ and the time is 5 hours.

[0009] Preferably, the solid-liquid mass ratio of the pretreated battery black powder to the deep eutectic solvent is 1:20.

[0010] Preferably, the stirring leaching temperature is 120°C and the time is 10 hours.

[0011] Preferably, the molar ratio of oxalic acid to choline chloride in the eutectic solvent is 1:1.

[0012] Preferably, the ratio of dimethyl sulfoxide to the eutectic solvent is 2-4 mL: 1 g.

[0013] Preferably, the heating temperature is 70°C.

[0014] Preferably, the carbon carrier comprises carbon paper.

[0015] Preferably, the molar ratio of Ni to Co in the electrodeposition solution is 1:(0.7~1).

[0016] This invention marks the first time that in-situ electrodeposition of a bimetallic alloy has been achieved on a carbon paper substrate using recycled nickel and cobalt oxalates. Carbon paper, as a planar conductive substrate, provides an ideal model platform for studying the synergistic effect of bimetallic alloys. The near-molar ratio of nickel to cobalt allows the electronic effects of both metals to be fully utilized, and the optimized electronic structure formed by alloying effectively modulates the adsorption energy for oxygen-containing intermediates. Simultaneously, precise control of the electrodeposition process enables highly uniform dispersion of alloy nanoparticles on the carbon fiber surface, successfully exposing the (111) and (200) highly active crystal planes, maximizing atomic efficiency.

[0017] The second technical solution of the present invention provides a carbon-supported catalyst for recovering transition metal alloys prepared according to the above-mentioned preparation method of carbon-supported catalyst for recovering transition metal alloys.

[0018] The third technical solution of the present invention provides an application of the above-mentioned carbon-supported catalyst for recovering transition metal alloys in the catalyst for oxygen evolution reaction in water electrolysis.

[0019] The beneficial technical effects of the present invention are as follows: This invention is the first to propose a short-process integrated process of "selective leaching and separation of DES-electrodeposition for direct catalyst regeneration". The core concept of this process route is to break down the barriers between traditional waste battery recycling and high-value material preparation, and to achieve direct conversion from waste to functional materials.

[0020] This invention demonstrates unique innovative thinking in the selection and design of leaching media. It extends the oxalic acid-choline chloride system, a deep eutectic solvent, from simple ternary materials to more complex waste lithium-ion battery coarse black powder. This system utilizes the unique coordination chemistry environment within DES (distilled lithium-ion battery emulsion) to achieve selective metal separation. In coarse black powder with significant compositional differences, the coordination ability between oxalate ions and different metal ions varies considerably. Combined with the role of choline chloride as a hydrogen bond acceptor in regulating the system's viscosity and reactivity, the leaching selectivity for nickel is significantly higher than that for cobalt and manganese. This discovery provides new ideas and theoretical basis for the treatment of complex waste materials. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 The process flow diagrams for preparing carbon paper-supported nickel-cobalt alloy catalysts in Examples 1-3 are shown.

[0023] Figure 2 The XRD patterns of the metal salt materials recovered in Examples 1 and 2 are compared with the XRD standard cards provided for Comparative Examples 1 and 2.

[0024] Figure 3 The FT-IR spectra of the metal salt materials recovered in Examples 1(a) and 2(b) are shown.

[0025] Figure 4 The SEM-EDS results are for the metal salt materials recovered in Examples 1(a) and 2(b).

[0026] Figure 5 The TEM test results and EDS scan results of the material prepared in Example 3 are shown below; (a) is a TEM image, (b) is a high-resolution transmission electron microscope (HRTEM) image, (c) is a selected area electron diffraction (SAED) pattern, and (d) is an EDS elemental distribution map.

[0027] Figure 6 Linear voltammetric scans (a) of the catalysts obtained in Example 3, Comparative Example 3, and Comparative Example 4; Tafel slope plots (b) of the catalysts obtained in Example 3, Comparative Example 3, and Comparative Example 4; cyclic voltammetric curves (c) of the catalyst obtained in Example 3; electrochemical impedance spectroscopy (Ed) of the catalyst obtained in Example 3; and chronovoltammetry results (e) of the catalyst obtained in Example 3. Detailed Implementation

[0028] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0029] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0030] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0031] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0032] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0033] Unless otherwise specified, room temperature in this invention refers to a temperature of 20±10℃.

[0034] Examples 1-2 Waste battery black powder purchased from the market was soaked in dimethyl carbonate (DMC) at 80°C and stirred for 1 hour. It was then washed by vacuum filtration with anhydrous ethanol and deionized water, and dried in a vacuum drying oven at 80°C for 12 hours. After that, it was calcined in a tube furnace at 900°C for 5 hours in air atmosphere to remove impurities and binders.

[0035] Mix 6.3035g OxA·2H2O with 6.981g ChCl (molar ratio 1:1) and stir in a flask at 50℃ for 30 min to obtain a transparent colorless liquid, namely DES.

[0036] The powder obtained from calcination in a tubular furnace was added to a flask containing DES preheated to 120°C at a solid-liquid mass ratio of 1:20. The mixture was stirred while being added at a stirring speed of 300 rpm. After stirring and leaching for 10 hours, the mixture was cooled to room temperature. Then, 15 mL of dimethyl sulfoxide was added to the flask each time, followed by centrifugation. This process was repeated three times. The separated precipitate was washed with anhydrous ethanol and used as the product of Example 1 (i.e., a substance mainly composed of nickel oxalate dihydrate). The centrifuged liquids from the first two centrifugations were combined, diluted with 100 mL of water, and then kept at 70°C for 3 hours. The precipitate was washed with anhydrous ethanol and used as the product of Example 2 (i.e., a substance mainly composed of cobalt oxalate dihydrate).

[0037] Example 3 Carbon paper (CP) cut to 1cm × 1cm was selected as the substrate for electrodeposition and placed in dilute hydrochloric acid (4mol·L⁻¹). -1The solution is subjected to ultrasonic treatment, followed by rinsing with anhydrous ethanol and deionized water until the pH of the filtrate is neutral. After pre-cleaning, the solution is placed in a petri dish and dried in a vacuum drying oven for later use.

[0038] Weigh 0.183 g of nickel oxalate dihydrate (containing approximately 0.9 mmol Ni) prepared in Example 1 and 0.185 g of cobalt oxalate dihydrate (containing approximately 0.75 mmol Co) prepared in Example 2, add them to 200 mL of water, add dilute hydrochloric acid to adjust the pH of the solution to 1 (using pH test paper), stir at 600 rpm for 2 h to obtain the electrodeposition solution.

[0039] Electrodeposition was performed using a typical three-electrode system on a Gamry electrochemical workstation. A pretreated carbon paper was clamped in a platinum electrode holder to form the working electrode, with a graphite electrode as the counter electrode and an Hg / HgO electrode as the reference electrode. The deposition current was -50 mA, and the deposition time was 30 min. The resulting carbon paper-supported nickel-cobalt alloy catalyst is denoted as Ni. 0.5 Co 0.5 (Ox)(H2O)2 / CP-(-50)-30.

[0040] The process flow diagrams for preparing carbon paper-supported nickel-cobalt alloy catalysts in Examples 1-3 are shown below. Figure 1 .

[0041] Comparative Example 1 Nickel oxalate was used as Comparative Example 1. The XRD standard card number for nickel oxalate is PDF#25-0581.

[0042] Comparative Example 2 Cobalt oxalate was used as a comparative example 2. The XRD standard card number for cobalt oxalate is PDF#25-0250.

[0043] Comparative Example 3 To more rigorously eliminate the influence of the energizing process and metal salts in the electrodeposition solution on the carbon paper, this invention also prepared a blank sample of carbon paper without metal loading. Specifically, no metal salts were added when preparing the electrodeposition solution, but the electrodeposition steps were performed in the same manner as in Example 3. This blank sample was named CP-(z)-m, where z represents the deposition current (mA) and m represents the deposition time (min).

[0044] Comparative Example 4 0.116 mg of commercial RuO2 catalyst was dispersed in 0.2 mL of ethanol, and Nafion solution (5 wt%, Sigma-Aldrich) was added. After ultrasonic oscillation, a uniform ink was formed, which was then drop-coated onto cleaned carbon paper at a pressure of 10 MPa. The ink was placed in a petri dish and then transferred to a vacuum drying oven to dry at 60 °C for 12 h to obtain the control catalyst.

[0045] The XRD patterns of the metal salt materials recovered in Examples 1 and 2 are shown in the XRD standard cards provided in Comparative Examples 1 and 2. Figure 2 .

[0046] from Figure 2 As can be seen from the data, the diffraction peaks of Examples 1 and 2 highly overlap with those of Comparative Examples 1 and 2, respectively, and no obvious impurity peaks appear.

[0047] The FT-IR spectra of the metal salt materials recovered in Examples 1(a) and 2(b) are shown below. Figure 3 .

[0048] from Figure 3 As can be seen in (a), several typical characteristic absorption peaks appeared in the spectrum of Example 1, all pointing to the molecular structure of nickel oxalate (NiC2O4·2H2O). Specifically, the peak at 3433 cm⁻¹... -1 A broad and strong absorption peak appeared at 1632 cm⁻¹, which is attributed to the stretching vibration of the O(H) bond in the water of crystallization or adsorbed water. The presence of this peak indicates that the recovered nickel oxalate exists in hydrate form, which is consistent with the expected control of the crystallization process by diluent in the process design. Furthermore, the spectrum also showed a peak at 1632 cm⁻¹. -1 A strong absorption peak is observed at 1358 cm⁻¹, corresponding to the coupling mode of the antisymmetric stretching vibration of the C=O and C–O bonds in oxalate, which is typical of oxalate compounds in this wavenumber range. Meanwhile, at 1358 cm⁻¹... -1 The peak at that position can be attributed to the symmetric stretching vibration of the C–O bond. The peak positions and shapes of the two peaks mentioned above are highly consistent with the fingerprint region characteristics of anhydrous and hydrated oxalates reported in the literature, further confirming the presence of the oxalate anion in the product and its coordination structure with nickel ions. Similarly, Figure 3 Figure (b) shows the infrared spectrum of Example 2. It can be observed that its overall spectral morphology is highly similar to that of Example 1, but there are subtle and systematic differences in the wavenumbers of key characteristic peaks. Firstly, in the range of 3600–3000 cm⁻¹… -1 The region also exhibits broad and strong O–H stretching vibration peaks, indicating that the product also exists in hydrate form. (1632 cm⁻¹) -1 With 1358cm -1 The presence of absorption peaks nearby indicates that the oxalate anion still exists as a ligand.

[0049] The SEM-EDS results of the metal salt materials recovered in Examples 1(a) and 2(b) are shown in the figure. Figure 4 .

[0050] Figure 4 As shown in (a), the signals of other metal elements, except for nickel, are extremely weak. Figure 4As shown in (b), the signals of other metal elements, except for cobalt, are extremely weak. The results are consistent with the XRD analysis, further confirming the success of the material recovery.

[0051] The TEM and EDS scan results of the material prepared in Example 3 are shown in the figure. Figure 5 Among them, (a) is a TEM image, (b) is a high-resolution transmission electron microscope (HRTEM) image, (c) is a selected area electron diffraction (SAED) pattern, and (d) is an EDS elemental distribution map.

[0052] Figure 5 As shown in (a), NiCo alloy nanoparticles with a size of approximately 5 nm are uniformly distributed along the carbon nanotubes. Figure 5 As shown in (b), the lattice fringes of the NiCo alloy have a spacing of 0.214 nm, which is very close to the (111) crystal plane of cobalt (0.205 nm) and nickel (0.203 nm). This finding strongly confirms the formation and loading of NiCo alloys on carbon materials. Figure 5 In the middle (c), bright diffraction spots corresponding to the (111) crystal plane are observed. Figure 5 As shown in (d), EDS elemental analysis confirmed the presence of nickel and cobalt and that the NiCo alloy was uniformly distributed on the carbon support surface.

[0053] Performance testing: The catalysts prepared in Examples 1, 3, and 4 all exhibited a rate of 5 mV·s in the range of 0 to 0.8 V (relative to the reduction electrode). −1 The LSV curve was recorded at the scan rate to avoid the oxidation peak interfering with the OER performance evaluation.

[0054] The reaction kinetic gradient characteristics of the catalysts prepared in Examples 1, 3, and 4 are given by the fitted Tafel slope plots. The Tafel slope is derived from the Tafel equation (η = a + b × logj), where η, a, b, and j represent the overpotential, adjustment constant, Tafel slope, and current density, respectively. Their values ​​are directly related to the rate-determining step and reaction mechanism.

[0055] At room temperature, within a voltage range of 1.08 V to 1.18 V, at scan rates of 20 to 100 mV s −1 Cyclic voltammetry curves measured in Example 1 are shown within the specified range. The shape of the cyclic voltammetry curves remains consistent across all scan rates. The current response and peak potential increase with increasing scan rate.

[0056] EIS measurements were performed on the catalysts prepared in Example 3 and Comparative Example 4 at 1.1 V vs RHE voltages, ranging from 100 kHz to 0.01 kHz, with AC voltages of 10 mV·rms and DC voltages of 0.64 V. The equivalent circuit, fitted by Zview from a Nyquist plot, then included the solution resistance (R... s ), charge transfer resistance (R) ct ) and constant phase element (CPE), R s Corresponding solution impedance, R ct Represents charge transfer resistance, while CPE reflects the double-layer capacitance of the electrode.

[0057] The stability of the catalyst prepared in Example 3 was characterized by a given current (current density of 10 mA·cm). −2 The time-voltage curves are given, and the stability of the catalyst has been tested over 80 hours.

[0058] All the above test work areas are 1cm×1cm.

[0059] Linear voltammetric scans (a) of the catalysts obtained in Example 3, Comparative Example 3, and Comparative Example 4; Tafel slope plots (b) of the catalysts obtained in Example 3, Comparative Example 3, and Comparative Example 4; cyclic voltammetric curves (c) of the catalyst obtained in Example 3; electrochemical impedance spectroscopy (E) of the catalyst obtained in Example 3; and chronovoltammetry results (e) of the catalyst obtained in Example 3 are shown below. Figure 6 .

[0060] like Figure 6 As shown in Figure (a), the OER reaction performance (black line) of Comparative Example 3 is far inferior to that of Example 3, and its contribution to the reaction activity is negligible. Furthermore, Example 3, at a current density of 10 mA·cm⁻¹… -2 The overpotential corresponding to this time is very close to the overpotential (η) of Comparative Example 4. 10 =303mV), this enhanced catalytic activity is related to the optimization of catalyst morphology and metal composition.

[0061] like Figure 6 As shown in (b), the Tafel slope of Example 3 is 77.95 mV·dec. -1 Lower than Comparative Example 3 (211.1 mV·dec) -1 ) and Comparative Example 4 (111.94 mV·dec -1 The lower Tafel slope indicates that the sample has faster reaction kinetics, suggesting that the bimetallic Example 3 has a greater advantage in catalytic kinetics.

[0062] Figure 6Figure (c) illustrates Example 3 at room temperature in a voltage range of 1.08V to 1.18V and a scan rate of 20 to 100 mV·s. -1 Cyclic voltammetry curves measured within the range. The shape of the cyclic voltammetry curves remained consistent at all scan rates. The current response and peak potential increased with increasing scan rate. This indicates that Example 3 has a high electrochemical active surface area (ECSA), which exposes more active sites, thereby enhancing the activity of the oxygen evolution reaction.

[0063] like Figure 6 As shown in (d), the equivalent circuit fitted by the Nyquist plot includes the solution resistance (R). s ), charge transfer resistance (R) ct ) and constant phase element (CPE), R s Corresponding solution impedance, R ct The charge transfer resistance (CPE) represents the charge transfer resistance, while the double-layer capacitance (CPE) reflects the electric double-layer capacitance of the electrode. The recorded charge transfer resistance is shown in Comparative Example 4 (4.94 Ω·cm). 2 Example 3 (1.9Ω·cm) 2 The lower charge transfer impedance indicates a more efficient charge transfer rate, resulting in a faster redox reaction, which is positive for improving catalytic activity and demonstrates that Example 3 has a high-efficiency charge transfer kinetic advantage.

[0064] like Figure 6 As shown in (e), the catalyst of Example 3 was subjected to a constant current density of 10 mA·cm⁻¹. -2 The catalyst maintains stable performance for at least 80 hours during continuous electrolysis, with minimal catalytic activity decay in the OER. Calculations show that the voltage decay rate of the catalyst is less than 3% of the initial performance. Overall, Example 3 demonstrates excellent stability.

[0065] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing a carbon-supported catalyst for recovering transition metal alloys, characterized in that, Includes the following steps: Battery black powder was soaked in dimethyl carbonate, and the separated solid material was washed, dried, and then calcined to obtain pretreated battery black powder. The pretreated battery black powder was mixed with a deep eutectic solvent composed of oxalic acid and choline chloride, stirred and leached, then dimethyl sulfoxide was added as a diluent, and then centrifuged. The separated precipitate was nickel oxalate. The separated solution was diluted with water and heated to precipitate cobalt oxalate. The recovered nickel oxalate and cobalt oxalate were dissolved in water and the pH was adjusted to 1-2 to obtain the electrodeposition solution; Nickel and cobalt in the electrodeposition solution are deposited onto a carbon support by electrodeposition to obtain a carbon support-supported recovery transition metal alloy catalyst.

2. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The soaking temperature is 80°C and the time is 1 hour; and / or the calcination temperature is 900°C and the time is 5 hours.

3. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The solid-liquid mass ratio of the pretreated battery black powder to the deep eutectic solvent is 1:

20.

4. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The stirring leaching temperature was 120℃, and the time was 10 hours.

5. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The ratio of dimethyl sulfoxide to the eutectic solvent is 2-4 mL: 1 g.

6. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The heating temperature is 70°C.

7. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The carbon carrier includes carbon paper.

8. The method for preparing a carbon-supported catalyst for recovering transition metal alloys according to claim 1, characterized in that, The molar ratio of Ni to Co in the electrodeposition solution is 1:(0.7~1).

9. A carbon-supported catalyst for recovering transition metal alloys prepared by the method of preparing a carbon-supported catalyst for recovering transition metal alloys according to any one of claims 1 to 8.

10. The application of the carbon-supported recycled transition metal alloy catalyst of claim 9 in the catalyst for the oxygen evolution reaction of water electrolysis.

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