High-entropy alloy catalyst and atomic-scale manufacturing method and application thereof

Abstract

The invention belongs to the technical field of catalysts, and particularly relates to a high-entropy alloy catalyst and an atomic-scale manufacturing method and application thereof. Compared with the prior art, the FeCoNiCrM high-entropy alloy film is deposited on the surface of the supporting body to serve as the high-entropy alloy catalyst, Cr and M are doped, when M comprises V, Cr and V serve as sacrificial dopants, and when M comprises Cu, Cu and other elements form a multi-element active center, so that all components of the high-entropy alloy are synergistically integrated to induce electronic modulation of a catalyst coordination environment; according to the high-entropy alloy catalyst, the oxygen evolution reaction efficiency is remarkably improved, in the reaction process, Cr and M components are controllably leached out, a structure rich in oxygen vacancies is generated, meanwhile, the structural integrity is kept through entropy stability, and therefore the high-entropy alloy catalyst shows excellent alkaline electrolysis water oxygen evolution reaction catalytic performance and excellent stability.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of catalysts, and particularly relates to a high-entropy alloy catalyst and an atomic-level manufacturing method and application thereof. BACKGROUND

[0002] The global energy crisis intensifies and the greenhouse effect worsens caused by over-reliance on fossil fuels, highlighting the urgency of transforming to a sustainable energy system. As a clean, renewable and sustainable energy carrier, hydrogen energy, with its zero-emission characteristics and diversified applications in the energy system, shows great potential to solve the decarbonization challenge and ensure long-term energy sustainability.

[0003] Current hydrogen production technologies are mainly divided into three categories: fossil fuel steam reforming, industrial by-product recovery (such as chlor-alkali process), and renewable energy driven water electrolysis. Among them, water electrolysis technology coupled with renewable energy, especially proton exchange membrane or alkaline electrolytic cell system, is considered the most feasible path for green hydrogen production due to its purity exceeding 99.99% and carbon neutral characteristics in the whole life cycle. The core electrochemical reaction of the water electrolysis process includes cathode hydrogen evolution reaction (HER) and anode oxygen evolution reaction (OER). OER involves a four-proton coupled electron transfer mechanism and a continuous adsorption / desorption process of oxygen intermediates, and its slow kinetic characteristics constitute the rate-determining step of the entire water electrolysis system.

[0004] Current industrial-grade OER electrocatalysts mainly rely on noble metal-based materials (such as Ir / Ru oxides), but their inherent scarcity and high cost seriously restrict the large-scale application of water electrolysis technology. This has prompted researchers to develop transition metal-based electrocatalysts with low cost and high performance, focusing on improving intrinsic activity through electronic structure regulation and optimizing active site accessibility through nanostructure engineering.

[0005] The most widely studied non-noble metal catalysts currently are Fe, Co, and Ni-based systems. The main modification strategies include: (1) nanostructure engineering to increase active site exposure (Chemical Society Reviews 2020, 49 (10), 3072-3106); (2) heteroatom doping to regulate electronic structure (ACS Catalysis 2022, 12 (17), 10808-10817); (3) heterojunction engineering to construct composite systems (InfoMat 5.1 (2023): e12377).

[0006] However, most of the existing catalysts are powder catalysts, and powder electrocatalytic materials have significant limitations in practical electrode applications: since they cannot be directly constructed into a self-supporting electrode system, they need to be fixed to the surface of a conductive substrate by relying on a polymer binder. Therefore, due to the presence of the binder, the contact area between the electrolyte and the powder electrocatalytic material is greatly reduced, the catalytic active sites are blocked, and the electrical resistance is increased, thereby leading to a decrease in catalytic performance. In addition, the mechanical bonding force is insufficient, which makes the catalyst prone to peeling under high current density conditions, resulting in relatively poor electrode stability.

[0007] Although self-supporting catalysts can be prepared to solve the above problems of powder catalysts, there are still many limitations in the existing preparation techniques of self-supporting catalysts, such as a long reaction period (usually > 12 hours) in the hydrothermal / solvothermal method, and a high-temperature and high-pressure environment that may damage heat-sensitive substrates (such as some polymers); the electrodeposition method is limited to conductive substrates, and uneven mass transfer of the solution may lead to edge effects, affecting the uniformity of large areas; the magnetron sputtering has a low ionization rate (usually < 10%), mainly neutral atoms, weak film adhesion, and serious particle agglomeration; and the atomic layer deposition relies on chemical adsorption, has low particle energy, slow deposition rate, and loose film. SUMMARY

[0008] Therefore, the technical problem to be solved by the present application is to provide a high-entropy alloy catalyst and an atomic-level manufacturing method and application thereof.

[0009] The present application provides a high-entropy alloy catalyst, which is a self-supporting catalyst, comprising a support body and a FeCoNiCrM high-entropy alloy film loaded on the surface of the support body; M is V and / or Cu; and the FeCoNiCrM high-entropy alloy film has an amorphous structure.

[0010] Preferably, the content of Fe atoms in the FeCoNiCrM high-entropy alloy film is 15% to 25%;

[0011] The content of Co atoms in the FeCoNiCrM high-entropy alloy film is 15% to 25%;

[0012] The content of Ni atoms in the FeCoNiCrM high-entropy alloy film is 15% to 25%;

[0013] The content of Cr atoms in the FeCoNiCrM high-entropy alloy film is 10% to 20%;

[0014] The content of M atoms in the FeCoNiCrM high-entropy alloy film is 15% to 30%.

[0015] Preferably, the catalyst comprises a support body and a FeCoNiCrV high-entropy alloy film loaded on the surface of the support body; and the content of V atoms in the FeCoNiCrV high-entropy alloy film is 20% to 30%.

[0016] Preferably, the support and the FeCoNiCrCu high-entropy alloy film loaded on the surface of the support are comprised; the content of Cu atoms in the FeCoNiCrCu high-entropy alloy film is 15% to 25%.

[0017] Preferably, the thickness of the FeCoNiCrM high-entropy alloy film is 90 to 600 nm.

[0018] The application further provides an atomic-level manufacturing method of the high-entropy alloy catalyst.

[0019] S) depositing a FeCoNiCrM high-entropy alloy film on the surface of the support by a magnetic filter cathode vacuum arc deposition method to obtain the high-entropy alloy catalyst; the target material used in the magnetic filter cathode vacuum arc deposition method comprises a FeCoNi alloy target, a Cr target and an M target; the atomic ratio of Fe, Co and Ni in the FeCoNi alloy target is 1:1:1.

[0020] Preferably, the negative bias voltage of the magnetic filter cathode vacuum arc deposition method is-50 V to-150 V.

[0021] Preferably, the duty cycle of the magnetic filter cathode vacuum arc deposition method is 20% to 90%.

[0022] Preferably, the arc current of the FeCoNi alloy target is 90 to 150 A, the arc current of the Cr target is 80 to 150 A, and the arc current of the M target is 80 to 150 A during the magnetic filter cathode vacuum arc deposition method.

[0023] Preferably, the time of the magnetic filter cathode vacuum arc deposition method is 1 to 5 min.

[0024] Preferably, the step S) is specifically:

[0025] S1) pre-treating the support; the pre-treatment comprises ion cleaning.

[0026] S2) depositing a FeCoNiCrM high-entropy alloy film on the surface of the pre-treated support by a magnetic filter cathode vacuum arc deposition method to obtain the high-entropy alloy catalyst.

[0027] The ion cleaning is performed by using an inert gas and a Cr target; the flow rate of the inert gas is 0 to 100 sccm; the working pressure of the ion cleaning is 5×10 -3 ~2×10 -2Pa, the arc current of the Cr target during ion cleaning is 80-120 A, the ion cleaning is performed using a gradiently reduced negative bias, the gradient number of the gradiently reduced negative bias is 4, and the gradiently reduced negative bias is specifically -850V to -750V, -650V to -550V, -450V to -350V and -250V to -150V.

[0028] The ion cleaning time is 4-12 min.

[0029] The application further provides application of the high-entropy alloy catalyst in an alkaline electrolytic water oxygen evolution reaction.

[0030] Compared with the prior art, the FeCoNiCrM high-entropy alloy film is deposited on the surface of the support body as the high-entropy alloy catalyst, Cr and M are doped, when M includes V, Cr and V act as sacrificial dopants, when M includes Cu, Cu and other elements form a multi-element active center, the electronic modulation of the coordination environment of the catalyst is induced by the synergistic integration of the components of the high-entropy alloy, the oxygen evolution reaction efficiency is significantly improved, and in the reaction process, the Cr and / or V components can be controlled to leach out, a structure rich in oxygen vacancies is generated, and the structural integrity is maintained through entropy stability, so that the high-entropy alloy catalyst exhibits excellent alkaline electrolytic water oxygen evolution reaction catalytic performance and outstanding stability.

[0031] Further, the FeCoNiCrM high-entropy alloy film is deposited by a magnetic filter cathode vacuum arc deposition method, so that the film structure is compact, defects are few, and the bonding force with the support body is strong, so that the high-entropy alloy catalyst is used for the alkaline electrolytic water oxygen evolution reaction and exhibits excellent stability, not only can the problem of catalyst film falling off due to unstable bonding force in the electrolytic water process be solved, but also the controllable preparation of the high-entropy alloy catalyst is realized, the preparation method is simple, environmentally friendly, and suitable for large-scale production. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A preparation flowchart of the high-entropy alloy catalyst provided by the application is shown in the figure;

[0033] Figure 2 A scanning electron microscope image of the high-entropy alloy catalyst obtained in Examples 1-4 of the application is shown in the figure;

[0034] Figure 3 An X-ray diffraction pattern of the high-entropy alloy catalyst obtained in Examples 1-4 of the application and the catalysts obtained in Comparative Examples 1-2 is shown in the figure;

[0035] Figure 4 A linear sweep voltammetry curve of the high-entropy alloy catalyst obtained in Examples 1-4 of the application, the catalysts obtained in Comparative Examples 1-2 and a commercial RuO2 is shown in the figure;

[0036] Figure 5 Figure 1 is a stability test diagram of the high-entropy alloy catalyst obtained in Embodiment 2 of the present application, the catalyst obtained in Comparative Examples 1-2, and commercial RuO2. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present application.

[0038] The present application provides a high-entropy alloy catalyst, which is a self-supporting catalyst, comprising a support and a FeCoNiCrM high-entropy alloy film loaded on the surface of the support; M is V and / or Cu; the FeCoNiCrM high-entropy alloy film has an amorphous structure.

[0039] In a specific embodiment provided by the present application, the support is preferably an electrically conductive support, so that the high-entropy alloy catalyst can be used as an oxygen evolution reaction (OER) catalyst electrode for water electrolysis to produce hydrogen; specifically, the support is preferably a metal-based support or a carbon-based support; the metal-based support is preferably foamed nickel, foamed copper, foamed iron, copper foil, nickel foil, titanium foil, stainless steel foil, titanium mesh or stainless steel mesh; the carbon-based support is preferably carbon cloth, carbon paper or graphite felt.

[0040] In a specific embodiment provided by the present application, the support is preferably carbon cloth, foamed nickel, stainless steel foil or titanium foil.

[0041] In the present application, the surface of the support is loaded with a FeCoNiCrM high-entropy alloy film. High-entropy alloys (HEAs) are composed of five or more near-equi-molar main elements, and exhibit unique catalytic advantages: (1) multi-element synergy to realize customization of electronic structure; (2) high-entropy effect to ensure structural stability under harsh electrochemical conditions; (3) lattice distortion to optimize active site coordination environment; (4) cocktail effect to reduce reaction energy barrier and accelerate kinetics.

[0042] In a specific embodiment provided by the present application, the Fe atom content in the FeCoNiCrM high-entropy alloy film is preferably 15%-25%; alternatively, the Fe atom content in the FeCoNiCrM high-entropy alloy film is 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25% or a range between any two of the above values.

[0043] In an embodiment of the present application, the FeCoNiCrM high-entropy alloy thin film has a Co atomic content of 15% to 25%; optionally, the FeCoNiCrM high-entropy alloy thin film has a Co atomic content of 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, or a range between any two of the above values.

[0044] In an embodiment of the present application, the FeCoNiCrM high-entropy alloy thin film has a Ni atomic content of 15% to 25%; optionally, the FeCoNiCrM high-entropy alloy thin film has a Ni atomic content of 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, or a range between any two of the above values.

[0045] In an embodiment of the present application, the FeCoNiCrM high-entropy alloy thin film has a Cr atomic content of 10% to 20%; optionally, the FeCoNiCrM high-entropy alloy thin film has a Cr atomic content of 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, or a range between any two of the above values.

[0046] In an embodiment of the present application, the FeCoNiCrM high-entropy alloy thin film has a M atomic content of 15% to 30%; optionally, the FeCoNiCrM high-entropy alloy thin film has a M atomic content of 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 28%, 30%, or a range between any two of the above values.

[0047] In an embodiment of the present application, the FeCoNiCrM high-entropy alloy thin film is a FeCoNiCrV high-entropy alloy thin film; the high-entropy alloy catalyst comprises a support and a FeCoNiCrV high-entropy alloy thin film supported on the surface of the support; the FeCoNiCrV high-entropy alloy thin film has a V atomic content of 20% to 30%; optionally, the FeCoNiCrV high-entropy alloy thin film has a V atomic content of 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 28%, 30%, or a range between any two of the above values.

[0048] In a specific embodiment provided by the present application, the FeCoNiCrM high-entropy alloy film is a FeCoNiCrCu high-entropy alloy film; at this time, the high-entropy alloy catalyst comprises a support and a FeCoNiCrCu high-entropy alloy film loaded on the surface of the support; the Cu atom content in the FeCoNiCrCu high-entropy alloy film is preferably 15% to 25%; optionally, the Cu atom content in the FeCoNiCrCu high-entropy alloy film is 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25% or a range between any two of the above values.

[0049] In a specific embodiment provided by the present application, the thickness of the FeCoNiCrM high-entropy alloy film is preferably 90 to 600 nm; optionally, the thickness of the FeCoNiCrM high-entropy alloy film is 90 nm, 100 nm, 120 nm, 150 nm, 180 nm, 200 nm, 220 nm, 250 nm, 280 nm, 300 nm, 320 nm, 350 nm, 380 nm, 400 nm, 420 nm, 450 nm, 480 nm, 500 nm, 520 nm, 550 nm, 580 nm, 600 nm or a range between any two of the above values.

[0050] The present application deposits a FeCoNiCrM high-entropy alloy film on the surface of a support as a high-entropy alloy catalyst, wherein Cr and M are incorporated; when M comprises V, Cr and V act as sacrificial dopants; when M comprises Cu, Cu and other elements form a multi-element active center, so that the components of the high-entropy alloy are synergistically integrated to induce electronic modulation of the coordination environment of the catalyst, significantly improving the oxygen evolution reaction efficiency, and in the reaction process, the Cr and / or V components can be controlled to leach out, generating a structure rich in oxygen vacancies, while the structure integrity is maintained by entropy stability, so that the high-entropy alloy catalyst exhibits excellent alkaline electrolytic water oxygen evolution reaction catalytic performance and outstanding stability.

[0051] The present application also provides an atomic-level manufacturing method of the above high-entropy alloy catalyst, comprising the following steps: S) depositing a FeCoNiCrM high-entropy alloy film on the surface of a support by a magnetic filter cathode vacuum arc deposition method to obtain a high-entropy alloy catalyst; the target material used in the magnetic filter cathode vacuum arc deposition method comprises a FeCoNi alloy target, a chromium target and an M target; the atomic ratio of Fe, Co and Ni in the FeCoNi alloy target is 1:1:1.

[0052] Taking a carbon cloth as the support and a V target as the M target as an example, the flowchart of the atomic-level manufacturing method of the high-entropy alloy catalyst provided by the present application is shown in Figure 1 ​

[0053] In the present application, the source of all raw materials is not particularly limited and can be commercially available.

[0054] In a specific embodiment provided by the present application, in order to improve the bonding force between the support and the high-entropy alloy film, the support is preferably pretreated before being deposited by the magnetic filter cathode vacuum arc deposition method; specifically, the following steps are performed: S1) pretreating the support: the pretreatment comprises ion cleaning; S2) depositing a FeCoNiCrM high-entropy alloy film on the surface of the pretreated support by the magnetic filter cathode vacuum arc deposition method to obtain a high-entropy alloy catalyst.

[0055] In a specific embodiment provided by the present application, the support is preferably ultrasonically cleaned to remove impurities or dirt on the surface of the support, and then ion cleaned; the ultrasonic cleaning is preferably performed with alcohol, acetone and deionized water in sequence; the time for ultrasonic cleaning with different solvents is independently preferably 10-20 min, more preferably 13-18 min, and even more preferably 15 min.

[0056] In a specific embodiment provided by the present application, the ion cleaning is preferably performed with an inert gas and a Cr target; the inert gas can be any inert gas known to those skilled in the art and is not particularly limited, and can be specifically argon, and more specifically argon with a purity of 99.99%; the flow rate of the inert gas is preferably 0-100 sccm; optionally, the flow rate of the inert gas is 0 sccm, 5 sccm, 10 sccm, 20 sccm, 30 sccm, 40 sccm, 50 sccm, 60 sccm, 70 sccm, 80 sccm, 90 sccm, 100 sccm or a range between any two of the above values; the arc current of the Cr target during ion cleaning is preferably 80-120 A; optionally, the arc current of the Cr target during ion cleaning is 80 A, 90 A, 100 A, 110 A, 120 A or a range between any two of the above values; cleaning with the Cr target can not only remove impurities such as oxide films and organic matter on the surface of the support to avoid damaging the surface microstructure, but also improve the adhesion of the subsequent film.

[0057] In a specific embodiment provided by the present application, the ion cleaning is preferably performed in the equipment for magnetic filter cathode vacuum arc deposition, and the deposition of the high-entropy alloy film can be directly performed after ion cleaning to avoid introducing other impurities.

[0058] In a specific embodiment provided by the present application, in order to reduce the influence of residual gas on the deposited coating film, the vacuum treatment is preferably performed before the ion cleaning, and then the inert gas is introduced to the working pressure for the ion cleaning; the vacuum treatment is preferably performed to a pressure of less than 5×10 -3 Pa.

[0059] In a specific embodiment provided by the present application, the working pressure of the ion cleaning is preferably 5×10 -3 ~2×10 -2 Pa; alternatively, the working pressure of the ion cleaning is 5×10 -3 Pa, 9×10 -3 Pa, 1×10 -2 Pa, 2×10 -2 Pa, or a range between any two of the above values.

[0060] In a specific embodiment provided by the present application, the time of the ion cleaning is preferably 4-12 min; alternatively, the time of the ion cleaning is 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 11 min, 12 min, or a range between any two of the above values.

[0061] In a specific embodiment provided by the present application, the ion cleaning is preferably performed by using the gradient-decreasing negative bias; the ion cleaning performed by using the gradient-decreasing negative bias can reduce the surface damage, improve the cleaning uniformity, and optimize the surface activity; the gradient number of the gradient-decreasing negative bias is 4, preferably, the gradient-decreasing negative bias is specifically -850V to -750V, -650V to -550V, -450V to -350V, and -250V to -150V; more preferably, the gradient-decreasing negative bias is specifically -820V to -780V, -620V to -580V, -420V to -380V, and -220V to -180V; still more preferably, the gradient-decreasing negative bias is specifically -800V, -600V, -400V, and -200V; the cleaning time of the four gradients can be the same or different, and there is no special limitation; in the present application, the cleaning time of the four gradients is independently preferably 1-3 min, more preferably 1-2 min, and still more preferably 1 min.

[0062] FeCoNiCrM high-entropy alloy film is deposited on the surface of a support or a pretreated support by a magnetic filter cathode vacuum arc deposition method; the magnetic filter cathode vacuum arc deposition method is an advanced load energy deposition method developed on the basis of a traditional cathode vacuum arc deposition technology, and can filter neutral droplets generated in an arc process through a magnetic filter elbow.

[0063] In a specific embodiment provided by the application, the magnetic filter cathode vacuum arc deposition filters neutral droplets and large particles generated in the arc process through a 90° magnetic filter elbow.

[0064] In a specific embodiment provided by the application, the deposition of the FeCoNiCrM high-entropy alloy film on the surface of the support is started when the gas pressure is lower than 5*10 -3 Pa; and no gas is introduced during the deposition.

[0065] In a specific embodiment provided by the application, the negative bias voltage of the magnetic filter cathode vacuum arc deposition is preferably-50V to-150V; alternatively, the negative bias voltage of the magnetic filter cathode vacuum arc deposition is-50V, -60V, -70V, -80V, -90V, -100V, -110V, -120V, -130V, -140V, -150V or a range between any two of the above values.

[0066] In a specific embodiment provided by the application, the duty cycle of the magnetic filter cathode vacuum arc deposition is preferably 20% to 90%; alternatively, the duty cycle of the magnetic filter cathode vacuum arc deposition is 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or a range between any two of the above values.

[0067] In a specific embodiment provided by the application, the magnetic filter cathode vacuum arc deposition adopts a multi-arc magnetic filter cathode deposition system.

[0068] In a specific embodiment provided by the application, the arc current of the iron-cobalt-nickel alloy target during the magnetic filter cathode vacuum arc deposition is preferably 90A to 150A; alternatively, the arc current of the iron-cobalt-nickel alloy target is 90A, 100A, 110A, 120A, 130A, 140A, 150A or a range between any two of the above values.

[0069] In a specific embodiment provided by the present application, the arc current of the chromium target during the magnetic filtered cathodic vacuum arc deposition is preferably 80-150 A; alternatively, the arc current of the chromium target is 80 A, 90 A, 100 A, 110 A, 120 A, 130 A, 140 A, 150 A or a range between any two of the above values.

[0070] In a specific embodiment provided by the present application, the arc current of the M target during the magnetic filtered cathodic vacuum arc deposition is preferably 80-150 A; alternatively, the arc current of the M target is 80 A, 90 A, 100 A, 110 A, 120 A, 130 A, 140 A, 150 A or a range between any two of the above values.

[0071] In a specific embodiment provided by the present application, the time for the magnetic filtered cathodic vacuum arc deposition is 1-5 min; alternatively, the time for the magnetic filtered cathodic vacuum arc deposition is 1 min, 2 min, 3 min, 4 min, 5 min or a range between any two of the above times.

[0072] The FeCoNiCrM high-entropy alloy thin film is deposited by the magnetic filtered cathodic vacuum arc deposition method, so that the thin film has a compact structure, few defects and strong bonding force with the support, thereby making the high-entropy alloy catalyst used for the alkaline water electrolysis oxygen evolution reaction exhibit excellent stability, solving the problem of catalyst film falling off due to unstable bonding force in the water electrolysis process, realizing controllable preparation of the high-entropy alloy catalyst, and the preparation method is simple, environment-friendly and suitable for large-scale production.

[0073] The present application also provides a use of the above high-entropy alloy catalyst in the alkaline water electrolysis oxygen evolution reaction.

[0074] In order to further illustrate the present application, the following embodiments describe a high-entropy alloy catalyst and an atomic-level manufacturing method and application thereof provided by the present application in detail.

[0075] The reagents used in the following examples are commercially available.

[0076] Example 1

[0077] In step S101, the pre-cleaning step includes: ultrasonic cleaning the titanium foil with alcohol, acetone and deionized water for 15 min each to remove impurities or dirt on the surface of the substrate.

[0078] In step S102, the ion cleaning step includes: after completing the pre-cleaning step, placing the substrate into a vacuum chamber, installing it on a sample table, and vacuumizing to below 5*10 -3Pa, start the rotating sample table, and pass in argon gas at a flow rate of 20 sccm, and the working gas pressure in the vacuum chamber is 9x10 -3 Pa, start the gas ion source, and use the Cr target to perform cleaning, the arc current is 100 A, and the substrate is sputtered and cleaned for 60 s under pulse bias voltages of -800 V, -600 V, -400 V, and -200 V in sequence.

[0079] In step S103, the high-entropy alloy deposition step includes: stopping the passing in of argon gas, and vacuumizing to a gas pressure of less than 5x10 -3 Pa, start the rotating sample table, set the negative bias voltage to -100 V, and the duty cycle to 20%, the arc current of the Fe-Co-Ni target (atomic ratio of 1:1:1) is 120 A, the arc current of the Cr target is 80 A, the arc current of the V target is 80 A, the sputtering time is 2 min, and the sample is marked as FeCoNiCrV-1.

[0080] Example 2

[0081] In step S101, the pre-cleaning step includes: sequentially ultrasonic cleaning the carbon cloth with alcohol, acetone, and deionized water for 15 min, so as to remove impurities or dirt on the surface of the substrate.

[0082] In step S102, the ion cleaning step includes: after the pre-cleaning step is completed, placing the substrate into the vacuum chamber, installing the substrate on the sample table, vacuumizing to a gas pressure of less than 5x10 -3 Pa, start the rotating sample table, and pass in argon gas at a flow rate of 50 sccm, and the working gas pressure in the vacuum chamber is about 6x10 -2 Pa, start the gas ion source, and use the Cr target to perform cleaning, the arc current is 100 A, and the substrate is sputtered and cleaned for 60 s under pulse bias voltages of -800 V, -600 V, -400 V, and -200 V in sequence.

[0083] In step S103, the high-entropy alloy deposition step includes: stopping the passing in of argon gas, and vacuumizing to a gas pressure of less than 5x10 -3 Pa, start the rotating sample table, set the negative bias voltage to -50 V, and the duty cycle to 90%, the arc current of the Fe-Co-Ni target (atomic ratio of 1:1:1) is 120 A, the arc current of the Cr target is 100 A, the arc current of the V target is 100 A, the sputtering time is 2 min, and the sample is marked as FeCoNiCrV-2.

[0084] Example 3

[0085] In step S101, the pre-cleaning step includes: sequentially ultrasonic cleaning the carbon cloth with alcohol, acetone, and deionized water for 15 min, so as to remove impurities or dirt on the surface of the substrate.

[0086] In step S102, the ion cleaning step includes: after the pre-cleaning step is completed, the substrate is placed into the vacuum chamber, installed on the sample table, vacuumed to below 5×10 -3 Pa, argon gas is introduced after the rotating sample table is started, the argon gas flow is 80 sccm, the working gas pressure of the vacuum chamber is 4×10 -2 Pa, the gas ion source is started, the Cr target is used for cleaning, the arc current is 100 A, and the substrate is sputtered and cleaned for 60 s under pulse bias voltages of -800 V, -600 V, -400 V and -200 V in sequence.

[0087] In step S103, the high-entropy alloy deposition step includes: stopping the introduction of argon gas, vacuuming to a gas pressure below 5×10 -3 Pa, the rotating sample table is started, the negative bias is set to -100 V, the duty cycle is 40%, the iron-cobalt-nickel target (atomic ratio 1:1:1) arc current is 120 A, the Cr target arc current is 140 A, the V target arc current is 140 A, the sputtering time is 3 min, and it is marked as FeCoNiCrV-3.

[0088] Example 4

[0089] In step S101, the pre-cleaning step includes: the carbon cloth is ultrasonically cleaned with alcohol, acetone and deionized water for 15 min in sequence, and impurities or dirt on the surface of the substrate is removed.

[0090] In step S102, the ion cleaning step includes: after the pre-cleaning step is completed, the substrate is placed into the vacuum chamber, installed on the sample table, vacuumed to below 5×10 -3 Pa, argon gas is introduced after the rotating sample table is started, the argon gas flow is 50 sccm, the working gas pressure of the vacuum chamber is about 6×10 -2 Pa, the gas ion source is started, the Cr target is used for cleaning, the arc current is 100 A, and the substrate is sputtered and cleaned for 60 s under pulse bias voltages of -800 V, -600 V, -400 V and -200 V in sequence.

[0091] In step S103, the high-entropy alloy deposition step includes: stopping the introduction of argon gas, vacuuming to a gas pressure below 5×10 -3 Pa, the rotating sample table is started, the negative bias is set to -50 V, the duty cycle is 90%, the iron-cobalt-nickel target (atomic ratio 1:1:1) arc current is 120 A, the Cr target arc current is 100 A, the Cu target arc current is 100 A, the sputtering time is 2 min, and it is marked as FeCoNiCrCu.

[0092] Comparative Example 1

[0093] According to the method of Example 2, except that there is no V target in the step of depositing a high-entropy alloy in step S103, a catalyst is obtained.

[0094] Comparative Example 2

[0095] The catalyst was prepared according to the method of Example 2, except that the Cr target and V target were not present in the step of depositing the high-entropy alloy in step S103.

[0096] The self-supporting high-entropy alloy catalysts obtained in Examples 1-4 were analyzed using scanning electron microscopy, and their SEM images are shown below. Figure 2 As shown, where a is Example 1, b is Example 2, c is Example 3, and d is Example 4, from... Figure 2 The catalyst film surface is uniform, and no detectable impurities or large particles were found. This microstructure characterization confirms the high purity and high quality of the deposited HEA coating.

[0097] The self-supporting high-entropy alloy catalysts obtained in Examples 1-4 and the catalysts obtained in Comparative Examples 1 and 2 were analyzed using X-ray diffraction, and their X-ray diffraction patterns are shown below. Figure 3 As shown. By Figure 3 It can be seen that the HEA film prepared on the surface has an amorphous structure.

[0098] The OER performance of the self-supporting high-entropy alloy catalysts obtained in Examples 1-4, the catalysts obtained in Comparative Examples 1-2, and commercial RuO2 was tested in 1 M KOH electrolyte, and their linear sweep voltammetric curves are shown below. Figure 4 As shown (scan rate is 5 mV / s) -1 (No ohmic compensation was performed). Test conditions: The working electrode was the prepared catalyst, the counter electrode was a graphite rod, and the reference electrode was a Hg / HgO electrode. The measured potential was obtained using formula E. RHE =E Hg / HgO +0.0591xpH+0.098V converts to a reversible hydrogen electrode (RHE). From Figure 4 The LSV curves show that the FeCoNiCrV-2 electrode at 10 mA·cm⁻¹… -2 It exhibits excellent catalytic performance, superior to FeCoNiCrV-1, FeCoNiCrV-3 and FeCoNiCrCu.

[0099] Furthermore, the self-supporting high-entropy alloy catalyst obtained in Example 2, the catalysts obtained in Comparative Examples 1 and 2, and commercial RuO2 were respectively tested in a 1 M KOH electrolyte at a current density of 20 mA·cm⁻¹. -2 Its stability was tested under the following conditions (other test conditions). Figure 4 (Similarly), this also indicates that the FeCoNiCrV-2 thin film catalyst has excellent lifetime, such as Figure 5 As shown.

[0100] As can be seen from the above, the high-entropy alloy catalyst provided by the application has greatly enhanced the bonding force between the HEA catalyst film and the substrate, effectively improving the stability of the electrode; the FCVA technology is used to deposit the catalyst film on the substrate, significantly reducing the micro-defects in the film forming process, ensuring the formation of an impurity-free, high-quality film. And it can ensure uniform distribution of elements and high purity; by selecting appropriate process parameters, precise control of elements can be achieved, thereby realizing controllable synthesis of HEA; FCVA technology introduces Cr and V as sacrificial components, which are selectively dissolved during electrochemical activation, generating oxygen vacancies in situ while maintaining structural stability.

[0101] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled persons in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A high-entropy alloy catalyst, characterized by, The high-entropy alloy catalyst is a self-supporting catalyst, comprising a support and a FeCoNiCrM high-entropy alloy film loaded on the surface of the support; M is V and / or Cu; the FeCoNiCrM high-entropy alloy film has an amorphous structure.

2. The high-entropy alloy catalyst of claim 1, wherein, The content of Fe atoms in the FeCoNiCrM high-entropy alloy film is 15% to 25%; The content of Co atoms in the FeCoNiCrM high-entropy alloy film is 15% to 25%; The content of Ni atoms in the FeCoNiCrM high-entropy alloy film is 15% to 25%; The content of Cr atoms in the FeCoNiCrM high-entropy alloy film is 10% to 20%; The content of M atoms in the FeCoNiCrM high-entropy alloy film is 15% to 30%.

3. The high-entropy alloy catalyst of claim 2, wherein, The FeCoNiCrV high-entropy alloy film comprises a support and a FeCoNiCrV high-entropy alloy film loaded on the surface of the support; the content of V atoms in the FeCoNiCrV high-entropy alloy film is 20% to 30%.

4. The high-entropy alloy catalyst of claim 2, wherein, The FeCoNiCrCu high-entropy alloy film comprises a support and a FeCoNiCrCu high-entropy alloy film loaded on the surface of the support; the content of Cu atoms in the FeCoNiCrCu high-entropy alloy film is 15% to 25%.

5. The high-entropy alloy catalyst of claim 1, wherein, The thickness of the FeCoNiCrM high-entropy alloy film is 90 to 600 nm.

6. A method of atomic-scale fabrication of the high-entropy alloy catalyst of claim 1, characterized by, The method comprises the following steps: S) depositing a FeCoNiCrM high-entropy alloy film on the surface of the support by a magnetic filter cathode vacuum arc deposition method to obtain a high-entropy alloy catalyst; the target material used in the magnetic filter cathode vacuum arc deposition comprises a Fe-Co-Ni alloy target, a Cr target and an M target; the atomic ratio of Fe, Co and Ni in the Fe-Co-Ni alloy target is 1:1:

1.

7. The atomic-scale manufacturing method of claim 6, wherein, The negative bias voltage of the magnetic filter cathode vacuum arc deposition is -50 V to -150 V. And / or, the duty cycle of the magnetic filter cathode vacuum arc deposition is 20% to 90%.

8. The atomic-scale fabrication method according to claim 6, wherein When the magnetic filter cathode vacuum arc deposition is performed, the arc current of the Fe-Co-Ni alloy target is 90 to 150 A, the arc current of the Cr target is 80 to 150 A, and the arc current of the M target is 80 to 150 A. And / or, the time of the magnetic filter cathode vacuum arc deposition is 1 to 5 min.

9. The atomic-scale fabrication method of claim 1, wherein, The step S) specifically comprises: S1) pretreating the support; the pretreatment comprises ion cleaning; S2) depositing a FeCoNiCrM high-entropy alloy film on the surface of the pretreated support by a magnetic filter cathode vacuum arc deposition method to obtain a high-entropy alloy catalyst; The ion cleaning is performed by using an inert gas and a Cr target; the flow rate of the inert gas is 0-100 sccm; the working pressure of the ion cleaning is 5×10 -3 ~2×10 -2 Pa; the arc current of the Cr target during the ion cleaning is 80-120 A; the ion cleaning is performed by using a gradiently reduced negative bias; the gradient number of the gradiently reduced negative bias is 4, specifically, -850 V to -750 V, -650 V to -550 V, -450 V to -350 V and -250 V to -150 V. The time of the ion cleaning is 4 to 12 min.

10. The use of the high-entropy alloy catalyst of any one of claims 1 to 5 or the high-entropy alloy catalyst prepared by the atomic-level manufacturing method of any one of claims 6 to 9 in an alkaline electrolytic water oxygen evolution reaction.

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