High-entropy alloy material and preparation method and application thereof

Abstract

The invention provides an oxide-loaded high-entropy alloy nanoparticle material as well as a preparation method and application thereof. The high-entropy alloy material comprises an oxide matrix and high-entropy alloy nanoparticles loaded on the surface of the oxide matrix, wherein the high-entropy alloy nanoparticles grow on the surface of the oxide matrix in situ. Therefore, strong interaction energy exists between the oxide matrix and the high-entropy alloy nanoparticles in the oxide-loaded high-entropy alloy nanoparticle material, the stability of the high-entropy alloy material can be improved, and meanwhile, the high-entropy alloy material also has excellent ionic conductivity and catalytic activity.

Description

Technical Field

[0001] This invention relates to the field of alloy materials, specifically to a high-entropy alloy material, its preparation method, and its applications. Background Technology

[0002] In recent years, high-entropy alloy nanomaterials have attracted widespread attention in the fields of catalysis, sensing, and energy materials due to their unique electronic and lattice structures. Their high configurational entropy design approach has greatly increased the variety of materials, providing entirely new ideas for the development of novel materials. At the same time, their thermodynamic high-entropy effect, kinetic hysteresis diffusion effect, structural lattice distortion effect, and performance-enhancing cocktail effect endow them with a wealth of new properties.

[0003] To date, researchers both domestically and internationally have developed numerous methods for preparing high-entropy alloy nanoparticles. Among them, the rapid Joule heating method proposed by Liangbing Hu of the University of Maryland has been widely used in the preparation of high-entropy alloy nanoparticles. The nanoparticles prepared by this method are uniform in size, contain 5 to 10 or more metallic elements, and exhibit good activity and stability in ammonia oxidation decomposition. However, this preparation method has some limitations. On the one hand, its preparation requires rapid heating and cooling techniques, making it unsuitable for applications requiring multi-step, slow-cooling device assembly. On the other hand, due to the high demand for carbon supports, it cannot be synthesized without carbon materials, and large-scale application is difficult.

[0004] Therefore, it is of great significance to develop a simple preparation method for high-entropy alloy nanoparticles that can be mass-produced. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0006] In a first aspect, the present invention provides an oxide-supported high-entropy alloy nanoparticle material. According to an embodiment of the present invention, the oxide-supported high-entropy alloy nanoparticle material comprises an oxide matrix and high-entropy alloy nanoparticles supported on the surface of the oxide matrix; wherein the high-entropy alloy nanoparticles are grown in situ on the surface of the oxide matrix.

[0007] In this invention, a strong interaction energy exists between the oxide matrix and the high-entropy alloy nanoparticles in the oxide-supported high-entropy alloy nanoparticle material. The formation of this strong interaction energy effectively improves the stability of the high-entropy alloy nanoparticles, effectively avoiding phase separation phenomena that may occur during the preparation process and subsequent applications, thereby ensuring the structural integrity and performance stability of the oxide-supported high-entropy alloy nanoparticle material. Furthermore, the presence of the matrix enables the formation of a metal-oxide interface, which also has a good effect on electron transfer and functional regulation within the material. In addition, this material exhibits synergistic activity of high-entropy materials, effectively enhancing the material's reactivity, especially for complex reactions requiring multiple active sites. Therefore, this oxide-supported high-entropy alloy nanoparticle material can be used as an electrode material for electrocatalytic reactions or as an active material for catalytic reactions.

[0008] According to embodiments of the present invention, the oxide-supported high-entropy alloy nanoparticle material may further include at least one of the following additional technical features:

[0009] According to an embodiment of the present invention, the metal elements in the high-entropy alloy nanoparticles include at least five of the following: Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, and Ag.

[0010] According to an embodiment of the present invention, the oxide matrix includes at least one of fluorite, spinel, and perovskite.

[0011] According to an embodiment of the present invention, the high-entropy alloy nanoparticles comprise FeCoNiCuM, where M is Au, Ag, Pt, Pd, Ru, Ir, or Sn.

[0012] According to an embodiment of the present invention, the fluorite includes CeO2 and its La, Sm, and Nd doped materials, and ZrO2 and its La, Sm, and Nd doped materials.

[0013] According to embodiments of the present invention, the spinel comprises MgAl2O4, MnCr2O4 or Mn2TiO4.

[0014] According to an embodiment of the present invention, the perovskite includes at least one of (La,Sr)(Mn,Ti)O3 perovskite, La(Fe,Co,Ni,Cu,Sn)O3, (La,Sr)(Ni,Ti)O3, and (La,Sr)(Fe,Co,Ni,Ti)O3.

[0015] According to an embodiment of the present invention, the total loading of the high-entropy alloy nanoparticles is 0.5wt%-20wt%.

[0016] According to an embodiment of the present invention, the particle size of the high-entropy alloy nanoparticles is 10nm-100nm.

[0017] In a second aspect, the present invention provides a method for preparing the oxide-supported high-entropy alloy nanoparticle material described in the first aspect. According to an embodiment of the present invention, the method includes: thermally reducing an oxide matrix doped with a metal element capable of forming high-entropy alloy nanoparticles, so that the metal element grows in situ on the surface of the oxide matrix to form high-entropy alloy nanoparticles, thereby obtaining the oxide-supported high-entropy alloy nanoparticle material.

[0018] In this invention, thermal reduction treatment enables the efficient dissolution and alloying of metal elements forming high-entropy alloy nanoparticles, resulting in in-situ generation of high-entropy alloy nanoparticles on the oxide matrix surface, thus avoiding the dissolution of other metals from the oxide matrix. This process not only achieves precise synthesis of nanoparticles but also enables precise control of the size, distribution, element types, and content of high-entropy alloy nanoparticles through precise regulation of thermal reduction parameters (such as temperature, time, and atmosphere composition). Furthermore, the method of this invention is characterized by low cost and ease of mass production, making it suitable for industrial manufacturing. In addition, the oxide matrix and high-entropy alloy nanoparticles in the high-entropy alloy material prepared by this invention exhibit strong interactions, enhancing the stability of the high-entropy alloy nanoparticles and effectively suppressing phase separation of metal elements during slow cooling, thereby ensuring the structural integrity and performance stability of the oxide-loaded high-entropy alloy nanoparticle material under complex operating conditions. Moreover, the multi-element synergistic effect of the high-entropy alloy further enhances the catalytic activity of the material, making it suitable for applications such as hydrogen fuel cells and electrochemical sensors.

[0019] According to an embodiment of the present invention, the oxide matrix doped with metal elements capable of forming high-entropy alloy nanoparticles is prepared by a sol-gel method.

[0020] According to embodiments of the present invention, the doped metallic elements capable of forming high-entropy alloy nanoparticles include at least five of the following: Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, and Ag.

[0021] According to an embodiment of the present invention, the oxide matrix doped with a metal element capable of forming high-entropy alloy nanoparticles is prepared by the following method: a first mixing treatment is performed on the raw material for preparing the oxide matrix, the metal salt corresponding to the doped metal element capable of forming high-entropy alloy nanoparticles, and a solvent to obtain a first mixed solution; the first mixed solution and a complexing agent are then subjected to a second mixing treatment to obtain a second mixed solution; the second mixed solution is heated to obtain a gel; the gel is dried to obtain a carbonization precursor; and the carbonization precursor is calcined to obtain the oxide matrix doped with the metal element capable of forming high-entropy alloy nanoparticles.

[0022] According to an embodiment of the present invention, the temperature of the thermal reduction treatment is 400℃-1000℃.

[0023] According to an embodiment of the present invention, the heat reduction treatment time is 1h-10h.

[0024] According to an embodiment of the present invention, the thermal reduction treatment is carried out in a reducing atmosphere.

[0025] According to an embodiment of the present invention, the reducing atmosphere includes at least one of hydrogen, nitrogen, carbon monoxide, ammonia, and methane.

[0026] According to an embodiment of the present invention, the solvent is water.

[0027] According to an embodiment of the present invention, in the second mixed solution, the molar ratio of total metal ions to the complexing agent in the first mixed solution is 1:(2.5-7).

[0028] According to an embodiment of the present invention, the complexing agent is selected from at least one of organic acids and organic alcohols.

[0029] According to an embodiment of the present invention, the organic acid is selected from at least one of citric acid, ethylenediaminetetraacetic acid (EDTA), ascorbic acid, and glycine.

[0030] According to embodiments of the present invention, the organic alcohol is selected from at least one of ethylene glycol, ethanol, acetone, n-propanol, and isopropanol.

[0031] According to an embodiment of the present invention, the complexing agent is selected from citric acid and ethylene glycol, wherein the molar ratio of citric acid to ethylene glycol is (2-5):(0.5-2).

[0032] According to an embodiment of the present invention, the temperature of the heat treatment is 80℃-150℃.

[0033] According to an embodiment of the present invention, the heat treatment is carried out under stirring conditions.

[0034] According to an embodiment of the present invention, the stirring rate is 100 rpm to 300 rpm.

[0035] According to an embodiment of the present invention, the drying temperature is 250℃-400℃.

[0036] According to an embodiment of the present invention, the drying process takes 2-10 hours.

[0037] According to an embodiment of the present invention, the calcination temperature is 800℃-1200℃.

[0038] According to an embodiment of the present invention, the calcination treatment time is 2h-20h.

[0039] In a third aspect, the present invention provides a catalyst. According to embodiments of the present invention, the catalyst comprises the oxide-supported high-entropy alloy nanoparticle material described in the first aspect or the oxide-supported high-entropy alloy nanoparticle material prepared by the method described in the second aspect. As mentioned above, the oxide-supported high-entropy alloy nanoparticle material of the present invention possesses excellent stability, ionic conductivity, and catalytic activity. Therefore, using the oxide-supported high-entropy alloy nanoparticle material as a catalyst, the synergistic effect of its multiple metal elements can significantly reduce the activation energy of the reaction, thereby improving the rate and efficiency of the catalytic reaction, while also exhibiting stable catalytic performance.

[0040] In a fourth aspect of the invention, the present invention proposes that the oxide-supported high-entropy alloy nanoparticle material of the first aspect, the oxide-supported high-entropy alloy nanoparticle material prepared by the method of the second aspect, or the catalyst of the third aspect have at least one of the following uses: as an active material for catalytic reactions; as an electrode material for electrocatalysis.

[0041] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0042] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0043] Figure 1 This is a design concept and mechanism diagram according to an embodiment of the present invention;

[0044] Figure 2 The Ellingham diagrams of the elements selected in Embodiment 1 of the present invention at different temperatures correspond to the free energies of the oxidation reactions of different elements.

[0045] Figure 3This is an experimental flowchart for preparing an oxide matrix doped with metal elements according to an embodiment of the present invention;

[0046] Figure 4 This is an X-ray diffraction pattern of a perovskite oxide (La,Sr)(Mn,Ti)O3-supported FeCoNiCuPd high-entropy alloy material according to an embodiment of the present invention.

[0047] Figure 5 The image is a scanning electron microscope (SEM) image of a perovskite oxide (La,Sr)(Mn,Ti)O3-supported FeCoNiCuPd high-entropy alloy material according to an embodiment of the present invention, wherein the arrow marks the dissolved high-entropy alloy nanoparticles.

[0048] Figure 6 These are transmission electron microscope and X-ray energy dispersive spectroscopy images of perovskite oxide (La,Sr)(Mn,Ti)O3-supported FeCoNiCuPd high-entropy alloy materials according to embodiments of the present invention.

[0049] Figure 7 These are transmission electron microscope and X-ray energy dispersive spectroscopy images of perovskite oxide (La,Sr)(Fe,Co,Ni,Cu,Sn)O3 perovskite-supported FeCoNiCuSn high-entropy alloy material according to embodiments of the present invention.

[0050] Figure 8 The image shows the impedance spectrum of a solid oxide cell using a perovskite oxide-supported FeCoNiCuPd high-entropy alloy material as an electrode, according to an embodiment of the present invention. Detailed Implementation

[0051] The embodiments of the present invention are described in detail below, and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0052] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0053] For the sake of brevity, this article only discloses some specific numerical ranges. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, just as any upper limit can be combined with any other upper limit to form an unspecified range. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and be combined with any other point or single value or with other lower or upper limits to form an unspecified range.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the invention, are intended to cover non-exclusive inclusion.

[0055] In this document, the terms “comprising” or “including” are open-ended expressions, meaning that they include the contents specified in this invention, but do not exclude other aspects.

[0056] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0057] This invention proposes high-entropy alloy materials, methods for preparing high-entropy alloy materials, catalysts, and their applications. These will be described in detail below.

[0058] High-entropy alloy materials

[0059] In a first aspect, the present invention provides an oxide-supported high-entropy alloy nanoparticle material. According to an embodiment of the present invention, the oxide-supported high-entropy alloy nanoparticle material comprises an oxide matrix and high-entropy alloy nanoparticles supported on the surface of the oxide matrix; wherein the high-entropy alloy nanoparticles are grown in situ on the surface of the oxide matrix.

[0060] In this invention, a strong interaction energy exists between the oxide matrix and the high-entropy alloy nanoparticles in the oxide-supported high-entropy alloy nanoparticle material. The formation of this strong interaction energy effectively improves the stability of the high-entropy alloy nanoparticles, effectively avoiding phase separation phenomena that may occur during the preparation process and subsequent applications, thereby ensuring the structural integrity and performance stability of the high-entropy alloy material. Furthermore, the presence of the matrix enables the formation of a metal-oxide interface, which also has a good effect on electron transfer and functional regulation within the material. In addition, this material exhibits synergistic activity of high-entropy materials, effectively enhancing the material's reactivity, especially for complex reactions requiring multiple active sites. Therefore, this oxide-supported high-entropy alloy nanoparticle material can be used as an electrode material for electrocatalytic reactions or as an active material for catalytic reactions.

[0061] In some embodiments of the present invention, the oxide-supported high-entropy alloy nanoparticle material may further include at least one of the following additional technical features:

[0062] In some embodiments of the present invention, the metallic elements in the high-entropy alloy nanoparticles include at least five of the following: Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, and Ag. Therefore, the synergistic activity of the high-entropy material can effectively enhance the material's reactivity, especially for complex reactions requiring multiple active sites. Furthermore, the high-entropy material exhibits a hysteresis diffusion effect, thus demonstrating good stability even at high temperatures.

[0063] It should be noted that the high-entropy alloy nanoparticles of this invention can be selected from any five or more metals chosen from "Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, Ag", including but not limited to FeCoNiCuPd, FeCoNiCuAu, FeCoNiCuAg, FeCoNiCuPt, FeCoNiCuRu, FeCoNiCuIr, and FeCoNiCuSn. The metals suitable for synthesizing the high-entropy alloy nanoparticles of this invention must meet the following condition: the free energy of the metal's reaction with oxygen under operating conditions should be greater than the free energy of hydrogen oxidation (to produce water). Figure 2 As shown, the oxidation free energies of the Fe, Co, Ni, Cu, and Pd metals selected in this invention are greater than the oxidation energy of hydrogen within a given temperature range. In this case, hydrogen tends to react with oxides, meaning it thermodynamically tends to reduce oxides to obtain metallic species.

[0064] In some embodiments of the present invention, the high-entropy alloy nanoparticles include at least one of FeCoNiCuPd, FeCoNiCuAu, FeCoNiCuAg, FeCoNiCuPt, FeCoNiCuRu, FeCoNiCuIr, and FeCoNiCuSn. Therefore, the above-mentioned types of high-entropy alloy nanoparticles enable oxide-loaded high-entropy alloy nanoparticle materials to possess better electrochemical performance, significantly reducing the adsorption energy barrier of fuels and improving fuel decomposition activity.

[0065] In some embodiments of the present invention, the oxide matrix includes at least one of fluorite, spinel, and perovskite.

[0066] It should be noted that by selecting different types of oxide matrix materials, on the one hand, the reaction scenarios of the materials can be expanded. For example, using spinel materials with high electrical conductivity can promote the application of materials in the field of low-temperature electrocatalysis. On the other hand, different matrix materials have different synthesis requirements. For example, compared with perovskite materials, fluorite structures can be synthesized at lower temperatures.

[0067] In some embodiments of the present invention, the fluorite includes CeO2 and its La, Sm, and Nd doped materials, and ZrO2 and its La, Sm, and Nd doped materials.

[0068] In some embodiments of the present invention, the spinel includes MgAl2O4, MnCr2O4 or Mn2TiO4.

[0069] In some embodiments of the present invention, the perovskite includes at least one selected from (La,Sr)(Mn,Ti)O3 perovskite, La(Fe,Co,Ni,Cu,Sn)O3, (La,Sr)(Ni,Ti)O3, and (La,Sr)(Fe,Co,Ni,Ti)O3. Therefore, when the perovskite is selected from the above types, the perovskite and high-entropy alloy nanoparticles can construct a metal-oxide interface. This interface significantly promotes electron transfer and functional regulation, enabling efficient electron transport and precise functional control. Simultaneously, it also promotes the in-situ growth of the metal forming the high-entropy alloy nanoparticles on the oxide matrix surface, effectively preventing the dissolution of other metal elements from the oxide matrix.

[0070] According to embodiments of the present invention, the total loading of the high-entropy alloy nanoparticles is 0.5 wt% to 20 wt%. For example, it can be 0.5 wt%, 1 wt%, 2 wt%, 5 wt%, 7 wt%, 10 wt%, 12 wt%, 15 wt%, 17 wt%, 20 wt%, etc., or any range of the above values. Therefore, by keeping the total loading within the above range, the oxide-loaded high-entropy alloy nanoparticle material can reduce material costs and improve economic efficiency while ensuring catalytic performance and stability. This avoids insufficient catalytic active sites due to excessively low loading, which reduces overall catalytic performance, and excessively high loading, which may lead to excessive aggregation of the high-entropy alloy nanoparticles, increasing particle size, and thus reducing specific surface area and catalytic activity.

[0071] According to an embodiment of the present invention, the particle size of the high-entropy alloy nanoparticles is 10 nm to 100 nm. For example, it can be 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, etc., or any range of the above values. Therefore, by ensuring the particle size of the high-entropy alloy nanoparticles is within the above range, the high-entropy alloy nanoparticles can provide a large number of active sites, thereby improving the activity of the catalytic reaction, reducing the activation energy, and accelerating the reaction rate.

[0072] Methods for preparing high-entropy alloy materials

[0073] In a second aspect, the present invention provides a method for preparing the oxide-supported high-entropy alloy nanoparticle material described in the first aspect. According to an embodiment of the present invention, the method includes: thermally reducing an oxide matrix doped with a metal element capable of forming high-entropy alloy nanoparticles, so that the metal element grows in situ on the surface of the oxide matrix to form the high-entropy alloy nanoparticles, thereby obtaining the oxide-supported high-entropy alloy nanoparticle material. According to an embodiment of the present invention, the mechanism of this method is shown in the diagram below. Figure 1 As shown, the high-entropy alloy material to be dissolved is first doped into an oxide matrix, where the elements exist in a highly oxidized ionic state. As the material undergoes reduction treatment, oxygen in the oxide matrix is ​​stripped away, reacting to generate water. This creates an oxygen gradient within the material, inducing metal ions to diffuse to the surface, where they are reduced to metal clusters. These metal clusters act as nucleation sites, inducing the continuous dissolution of other metals. Finally, the dissolved metal material gradually grows into high-entropy alloy nanoparticles.

[0074] In this invention, thermal reduction treatment enables the efficient dissolution and alloying of metal elements forming high-entropy alloy nanoparticles, resulting in in-situ generation of high-entropy alloy nanoparticles on the oxide matrix surface, thus avoiding the dissolution of other metals from the oxide matrix. This process not only achieves precise synthesis of nanoparticles but also enables precise control of the size, distribution, element types, and content of high-entropy alloy nanoparticles through precise regulation of thermal reduction parameters (such as temperature, time, and atmosphere composition). Furthermore, the method of this invention is characterized by low cost and ease of mass production, making it suitable for industrial manufacturing. In addition, the oxide matrix and high-entropy alloy nanoparticles in the high-entropy alloy material prepared by this invention exhibit strong interactions, enhancing the stability of the high-entropy alloy nanoparticles and effectively suppressing phase separation of metal elements during slow cooling, thereby ensuring the structural integrity and performance stability of the oxide-loaded high-entropy alloy nanoparticle material under complex working conditions. Moreover, the multi-element synergistic effect of the high-entropy alloy further enhances the catalytic activity of the material, giving it excellent ionic conductivity and catalytic activity.

[0075] In some embodiments of the present invention, the temperature of the thermal reduction treatment is 400℃-1000℃. For example, it can be 400℃, 500℃, 600℃, 700℃, 800℃, 900℃, 1000℃, etc., or any range of the above values. In some embodiments of the present invention, the time of the thermal reduction treatment is 1h-10h. For example, it can be 1h, 2h, 4h, 6h, 8h, 10h, etc., or any range of the above values. Therefore, by keeping the temperature and time of the thermal reduction treatment within the above range, it is possible to promote the effective dissolution of metal elements forming high-entropy alloy nanoparticles from the oxide matrix and form high-entropy alloy nanoparticles, while avoiding excessive growth of high-entropy alloy nanoparticles caused by excessively long reaction times.

[0076] In some embodiments of the present invention, the thermal reduction treatment is carried out in a reducing atmosphere. According to embodiments of the present invention, the reducing atmosphere may be used for a reduction reaction, and exemplaryly includes, but is not limited to, at least one of hydrogen, nitrogen, carbon monoxide, ammonia, and methane.

[0077] In some embodiments of the present invention, the thermal reduction process may be carried out, but is not limited to, in a heated and ventilated sealed tube furnace.

[0078] In some embodiments of the present invention, the doped metallic elements capable of forming high-entropy alloy nanoparticles include at least five of the following: Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, and Ag. Thus, high-entropy alloy nanoparticles can be formed.

[0079] In some embodiments of the present invention, the oxide matrix doped with metal elements capable of forming high-entropy alloy nanoparticles is prepared by a sol-gel method. According to embodiments of the present invention, refer to... Figure 3 The oxide matrix doped with metal elements capable of forming high-entropy alloy nanoparticles is prepared by the following method:

[0080] S100: First Mixing Process

[0081] In this process, the raw materials for preparing the oxide matrix, the metal salt corresponding to the doped metal element capable of forming high-entropy alloy nanoparticles, and the solvent are subjected to a first mixing treatment to obtain a first mixed solution.

[0082] It should be noted that the raw materials for the oxide matrix can be selected according to the specific type of oxide matrix. For example, when the oxide matrix is ​​selected from (La,Sr)(Mn,Ti)O3 perovskite, the raw materials can be lanthanum salts, strontium salts, titanium salts, and manganese salts. For example, they can specifically be La(NO3)3, Sr(NO3)2, di(2-hydroxypropionic acid)diammonium hydroxide titanium, or Mn(NO3)2.

[0083] It should be noted that the metal salt corresponding to the doped metal element can be selected according to the specific type of high-entropy alloy nanoparticles required. For example, when the high-entropy alloy nanoparticles are FeCoNiCuPd, the metal salt corresponding to the doped metal element can be iron salt, cobalt salt, nickel salt, copper salt, and palladium salt. For example, it can specifically be Fe(NO3)3, Co(NO3)2, Ni(NO3)2, Cu(NO3)2, or PdCl2.

[0084] It should be noted that when the metal elements contained in the oxide matrix are partially the same as those contained in the high-entropy alloy nanoparticles, these same elements can be provided by the raw materials of the oxide matrix or by the aforementioned metal salts. That is, the raw materials providing these same elements can generate both the oxide matrix and the high-entropy alloy nanoparticles. For example, when the perovskite is La(Fe,Co,Ni,Cu,Sn)O3 and the high-entropy alloy nanoparticles are FeCoNiCuSn, the total raw materials for both are La(NO3)3, Fe(NO3)3, Co(NO3)2, Ni(NO3)2, Cu(NO3)2, and SnCl4.

[0085] In some embodiments of the present invention, the solvent is water.

[0086] S200: Second Mixing Process

[0087] In this process, the first mixed solution and the complexing agent are subjected to a second mixing treatment to obtain a second mixed solution.

[0088] In some embodiments of the present invention, in the second mixed solution, the molar ratio of total metal ions to the complexing agent in the first mixed solution is 1:(2.5-7). For example, it can be 1:2.5, 1:3, 1:4, 1:5, 1:6, 1:7, etc., or a range of any of the above values. Therefore, by keeping the molar ratio of total metal ions to the complexing agent in the first mixed solution within the above range, the prepared material can have better uniformity.

[0089] In some embodiments of the present invention, the complexing agent is selected from at least one of organic acids and organic alcohols. In some embodiments of the present invention, the organic acid is selected from at least one of citric acid, ethylenediaminetetraacetic acid (EDTA), ascorbic acid, and glycine. In some embodiments of the present invention, the organic alcohol is selected from at least one of ethylene glycol, ethanol, acetone, n-propanol, and isopropanol.

[0090] In some embodiments of the present invention, the complexing agent is selected from citric acid and ethylene glycol, wherein the molar ratio of citric acid to ethylene glycol is (2-5):(0.5-2). For example, it can be 2:0.5, 3:1, 4:1.5, 2:2, etc., or any range of the above values. Thus, citric acid can fully react with metal ions to form a chelate, and the chelate undergoes a polyesterification reaction with ethylene glycol, thereby immobilizing the metal element within the gel.

[0091] S300: Heat treatment

[0092] In this process, the second mixed solution is heated to obtain a gel.

[0093] In some embodiments of the present invention, the temperature of the heat treatment is 80℃-150℃. For example, it can be 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, etc., or it can be any range of the above values.

[0094] In some embodiments of the present invention, the heat treatment is performed under stirring conditions. According to embodiments of the present invention, the stirring rate is 100 rpm to 300 rpm. For example, it can be 100 rpm, 150 rpm, 200 rpm, 250 rpm, 300 rpm, etc., or a range of any of the above values.

[0095] S400: Drying process

[0096] In this process, the gel is dried to obtain a carbonized precursor.

[0097] In some embodiments of the present invention, the drying temperature is 250℃-400℃. For example, it can be 250℃, 270℃, 300℃, 320℃, 350℃, 370℃, 400℃, etc., or it can be any range of the above values.

[0098] In some embodiments of the present invention, the drying time is 2h-10h. For example, it can be 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, or any range of the above values.

[0099] S500: Calcination treatment

[0100] In this process, the carbonized precursor is calcined to obtain the oxide matrix doped with metal elements.

[0101] In some embodiments of the present invention, the calcination temperature is 800℃-1200℃. For example, it can be 800℃, 900℃, 1000℃, 1100℃, 1200℃, etc., or it can be any range of the above values.

[0102] In some embodiments of the present invention, the calcination treatment time is 2h-20h. For example, it can be 2h, 5h, 7h, 10h, 12h, 15h, 17h, 20h, etc., or it can be any range of the above values.

[0103] catalyst

[0104] In a third aspect, the present invention provides a catalyst. According to embodiments of the present invention, the catalyst comprises the oxide-supported high-entropy alloy nanoparticle material described in the first aspect or the oxide-supported high-entropy alloy nanoparticle material prepared by the method described in the second aspect. As mentioned above, the oxide-supported high-entropy alloy nanoparticle material of the present invention possesses excellent stability, ionic conductivity, and catalytic activity. Therefore, using the oxide-supported high-entropy alloy nanoparticle material as a catalyst, the synergistic effect of its multiple metal elements can significantly reduce the activation energy of the reaction, thereby improving the rate and efficiency of the catalytic reaction, while also exhibiting stable catalytic performance.

[0105] application

[0106] In a fourth aspect of the invention, the present invention proposes that the oxide-supported high-entropy alloy nanoparticle material of the first aspect, the oxide-supported high-entropy alloy nanoparticle material prepared by the method of the second aspect, or the catalyst of the third aspect have at least one of the following uses: as an active material for catalytic reactions; as an electrode material for electrocatalysis.

[0107] In some embodiments of the present invention, the catalytic reaction includes, but is not limited to, organic dehydrogenation, methane reforming dehydrogenation, and nitrogen oxide removal.

[0108] In some embodiments of the present invention, the electrocatalysis includes, but is not limited to, water electrolysis and nitrate electroreduction.

[0109] The embodiments of the present invention are described in detail below. These embodiments are exemplary and are only used to explain the present invention, and should not be construed as limiting the invention. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0110] Example 1: Preparation of (La,Sr)(Mn,Ti)O3 perovskite-supported FeCoNiCuPd high-entropy alloy material

[0111] 1. Accurately weigh the metal salts according to the stoichiometric ratio. In this example, La(NO3)3, Sr(NO3)2, diammonium di(2-hydroxypropionic acid) hydroxide titanium, Mn(NO3)2, Fe(NO3)3, Co(NO3)2, Ni(NO3)2, Cu(NO3)2, and PdCl2 are used. The metals are dissolved in deionized water to obtain a homogeneous metal ion solution.

[0112] 2. Weigh citric acid and ethylene glycol according to the ratio of total metal ions: citric acid: ethylene glycol = 1:2:2 (molar ratio), dissolve them completely, and then mix them with the above metal solution to obtain a sol.

[0113] 3. Place the above sol in a beaker-like glass container and put it in a heated stirring apparatus such as a magnetic stirrer to completely evaporate the water and obtain a gel. Heating temperature: 100℃, stirring speed: 200 rpm.

[0114] 4. Dry the above gel to obtain the carbonized precursor. The drying temperature is 100°C and the drying time is 10 hours.

[0115] 5. Calcine the above-mentioned carbonization precursor to obtain the target oxide material. The calcination temperature is 1000℃ and the calcination time is 4 hours.

[0116] 6. The above oxides are placed in a tube furnace for thermal reduction treatment. The heating temperature is 800℃, the atmosphere is 4% H2 / N2, and the reduction time is 4 hours to obtain a high-entropy alloy material of (La,Sr)(Mn,Ti)O3 perovskite supported on FeCoNiCuPd.

[0117] Example 2: Preparation of La(Fe,Co,Ni,Cu,Sn)O3 perovskite-supported FeCoNiCuSn high-entropy alloy material

[0118] 1. Weigh the metal salts accurately according to the stoichiometric ratio. In this example, La(NO3)3, Fe(NO3)3, Co(NO3)2, Ni(NO3)2, Cu(NO3)2, and SnCl4 are used. The metals are dissolved in deionized water to obtain a homogeneous metal ion solution.

[0119] 2. Weigh citric acid and ethylene glycol according to the ratio of total metal ions: citric acid: ethylene glycol = 1:2:2 (molar ratio), dissolve them completely, and then mix them with the above metal solution to obtain a sol.

[0120] 3. Place the above sol in a beaker-like glass container and put it in a heated stirring apparatus such as a magnetic stirrer to completely evaporate the water and obtain a gel. Heating temperature: 100℃, stirring speed: 200 rpm.

[0121] 4. Dry the above gel to obtain the carbonized precursor. The drying temperature is 250°C and the drying time is 10 hours.

[0122] 5. Calcine the above-mentioned carbonization precursor to obtain the target oxide material. The calcination temperature is 1000℃ and the calcination time is 4 hours.

[0123] 6. The above oxides are placed in a tube furnace for thermal reduction treatment. The heating temperature is 600℃, the atmosphere is 4% H2 / N2, and the reduction time is 2 hours to obtain a high-entropy alloy material of La(Fe,Co,Ni,Cu,Sn)O3 perovskite supported on FeCoNiCuSn.

[0124] Comparative Example 1: Preparation of Ni monometallic material supported on (La,Sr)(Ni,Ti)O3

[0125] 1. Weigh the metal salts accurately according to the stoichiometric ratio. In this example, La(NO3)3, Sr(NO3)2, diammonium di(2-hydroxypropionic acid) hydroxide titanium, and Ni(NO3)2 are used. The metals are dissolved in deionized water to obtain a homogeneous metal ion solution.

[0126] 2. Weigh citric acid and ethylene glycol according to the ratio of total metal ions: citric acid: ethylene glycol = 1:2:2 (molar ratio), dissolve them completely, and then mix them with the above metal solution to obtain a sol.

[0127] 3. Place the above sol in a beaker-like glass container and put it in a heated stirring apparatus such as a magnetic stirrer to completely evaporate the water and obtain a gel. Heating temperature: 100℃, stirring speed: 200 rpm.

[0128] 4. Dry the above gel to obtain the carbonized precursor. The drying temperature is 250°C and the drying time is 10 hours.

[0129] 5. Calcine the above-mentioned carbonization precursor to obtain the target oxide material. The calcination temperature is 1000℃ and the calcination time is 4 hours.

[0130] 6. The above oxides are placed in a tube furnace for thermal reduction treatment. The heating temperature is 800℃, the atmosphere is 4% H2 / N2, and the reduction time is 2 hours to obtain (La,Sr)(Ni,Ti)O3 perovskite-supported Ni single metal material.

[0131] Comparative Example 2: Preparation of FeCoNi ternary metal material supported on (La,Sr)(Fe,Co,Ni,Ti)O3

[0132] 1. Accurately weigh the metal salts according to the stoichiometric ratio. In this example, La(NO3)3, Sr(NO3)2, diammonium di(2-hydroxypropionic acid) hydroxide titanium, Fe(NO3)3, Co(NO3)2, and Ni(NO3)2 are used. The metals are dissolved in deionized water to obtain a homogeneous metal ion solution.

[0133] 2. Weigh citric acid and ethylene glycol according to the ratio of total metal ions: citric acid: ethylene glycol = 1:2:2 (molar ratio), dissolve them completely, and then mix them with the above metal solution to obtain a sol.

[0134] 3. Place the above sol in a beaker-like glass container and put it in a heated stirring apparatus such as a magnetic stirrer to completely evaporate the water and obtain a gel. Heating temperature: 100℃, stirring speed: 200 rpm.

[0135] 4. Dry the above gel to obtain the carbonized precursor. The drying temperature is 250°C and the drying time is 10 hours.

[0136] 5. Calcine the above-mentioned carbonization precursor to obtain the target oxide material. The calcination temperature is 1000℃ and the calcination time is 4 hours.

[0137] 6. The above oxides are placed in a tube furnace for thermal reduction treatment. The heating temperature is 800℃, the atmosphere is 4% H2 / N2, and the reduction time is 2 hours to obtain (La,Sr)(Fe,Co,Ni,Ti)O3 perovskite-supported FeCoNi ternary metal material.

[0138] Performance characterization and testing

[0139] 1. X-ray diffraction analysis was performed on the (La,Sr)(Mn,Ti)O3 perovskite-supported FeCoNiCuPd high-entropy alloy material prepared in Example 1. The results are as follows: Figure 4 As shown, the material mainly exhibits a trigonal perovskite structure with no obvious metal species, indicating that the generated metal species are small in size and well dispersed.

[0140] 2. Scanning electron microscopy analysis was performed on the (La,Sr)(Mn,Ti)O3 perovskite-supported FeCoNiCuPd high-entropy alloy material prepared in Example 1. The results are as follows: Figure 5As shown, the arrows indicate the generated nanoparticles, with particle sizes ranging from 10 to 30 nm and an average size of approximately 16 nm.

[0141] 3. Transmission electron microscopy and X-ray energy dispersive spectroscopy were performed on the (La,Sr)(Mn,Ti)O3 perovskite-supported FeCoNiCuPd high-entropy alloy material prepared in Example 1. The results are as follows: Figure 6 As shown, La, Sr, Mn, Ti, and O elements are mainly distributed in the perovskite matrix, while Fe, Co, Ni, Cu, and Pd elements are concentrated in the dissolved particles, indicating that the formed nanoparticles are FeCoNiCuPd alloys. Furthermore, some Fe, Co, Ni, Cu, and Pd elements remain inside the matrix, indicating that some metal ions were not completely dissolved.

[0142] 4. The high-entropy alloy material (La,Sr)(Fe,Co,Ni,Cu,Sn)O3 perovskite supported on FeCoNiCuSn prepared in Example 2 was analyzed by transmission electron microscopy and X-ray energy dispersive spectroscopy. The results are as follows: Figure 7 As shown, La and O elements are mainly distributed in the perovskite matrix, while Fe, Co, Ni, Cu, and Sn elements are concentrated in the dissolved particles, indicating that the formed nanoparticles are FeCoNiCuSn alloys. Furthermore, some Fe, Co, Ni, Cu, and Sn elements remain inside the matrix, indicating that the metal ions were not completely dissolved.

[0143] 5. Electrochemical impedance spectroscopy was performed on the high-entropy alloy materials prepared in Example 1 and Comparative Examples 1-2. The results are as follows: Figure 8 As shown, in Example 1, the battery impedance value of the dissolved FeCoNiCuPd is 0.72 Ωcm. -2 The battery impedance of Comparative Example 2, which dissolves FeCoNi, is 3.13 Ωcm. -2 The battery impedance of Comparative Example 1, which dissolves Ni, is 5.50 Ωcm. -2 It is evident that the impedance of the battery based on a single Ni dissolution electrode is 7.6 times that of the battery based on a dissolution high-entropy alloy electrode. Therefore, the oxide-supported high-entropy alloy nanoparticle material prepared by the method of this invention exhibits the best activity as an electrode material.

[0144] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0145] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An oxide-supported high-entropy alloy nanoparticle material, characterized in that, It includes an oxide matrix and high-entropy alloy nanoparticles loaded on the surface of the oxide matrix; wherein the high-entropy alloy nanoparticles are grown in situ on the surface of the oxide matrix.

2. The oxide-supported high-entropy alloy nanoparticle material according to claim 1, characterized in that, The high-entropy alloy nanoparticles contain at least five of the following metallic elements: Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, and Ag. Optionally, the oxide matrix includes at least one of fluorite, spinel, and perovskite.

3. The oxide-supported high-entropy alloy nanoparticle material according to claim 2, characterized in that, The high-entropy alloy nanoparticles include FeCoNiCuM, where M is Au, Ag, Pt, Pd, Ru, Ir, or Sn; Optionally, the fluorite includes CeO2 and its La, Sm, and Nd doped materials, and ZrO2 and its La, Sm, and Nd doped materials; Optionally, the spinel comprises MgAl2O4, MnCr2O4 or Mn2TiO4; Optionally, the perovskite includes (La,Sr)(Mn,Ti)O3, La(Fe,Co,Ni,Cu,Sn)O3, (La,Sr)(Ni,Ti)O3 or (La,Sr)(Fe,Co,Ni,Ti)O3; Optionally, the total loading of the high-entropy alloy nanoparticles is 0.5 wt% to 20 wt%. Optionally, the particle size of the high-entropy alloy nanoparticles is 10nm-100nm.

4. A method for preparing oxide-supported high-entropy alloy nanoparticles according to any one of claims 1-3, characterized in that, include: An oxide matrix doped with a metal element capable of forming high-entropy alloy nanoparticles is subjected to thermal reduction treatment so that the metal element grows in situ on the surface of the oxide matrix to form the high-entropy alloy nanoparticles, thereby obtaining the oxide-loaded high-entropy alloy nanoparticle material.

5. The method according to claim 4, characterized in that, The oxide matrix doped with metal elements capable of forming high-entropy alloy nanoparticles was prepared by the sol-gel method. Optionally, the doped metallic elements capable of forming high-entropy alloy nanoparticles include at least five of the following: Fe, Co, Ni, Cu, Zn, Sn, Pt, Pd, Ru, Ir, Au, and Ag.

6. The method according to claim 5, characterized in that, The oxide matrix doped with metal elements capable of forming high-entropy alloy nanoparticles is prepared by the following method: The raw materials for preparing the oxide matrix, the metal salt corresponding to the doped metal element capable of forming high-entropy alloy nanoparticles, and the solvent are subjected to a first mixing treatment to obtain a first mixed solution; The first mixed solution and the complexing agent are subjected to a second mixing treatment to obtain a second mixed solution; The second mixed solution was heated to obtain a gel; The gel was dried to obtain a carbonized precursor; The carbonized precursor is calcined to obtain the oxide matrix doped with metal elements capable of forming high-entropy alloy nanoparticles.

7. The method according to claim 4, characterized in that, The temperature of the thermal reduction treatment is 400℃-1000℃; Optionally, the heat reduction treatment time is 1h-10h; Optionally, the thermal reduction treatment is carried out in a reducing atmosphere; Optionally, the reducing atmosphere includes at least one of hydrogen, nitrogen, carbon monoxide, ammonia, and methane.

8. The method according to claim 6, characterized in that, The solvent is water; Optionally, in the second mixed solution, the molar ratio of total metal ions to the complexing agent in the first mixed solution is 1:(2.5-7); Optionally, the complexing agent is selected from at least one of organic acids and organic alcohols; Optionally, the organic acid is selected from at least one of citric acid, ethylenediaminetetraacetic acid, ascorbic acid, and glycine; Optionally, the organic alcohol is selected from at least one of ethylene glycol, ethanol, acetone, n-propanol, and isopropanol; Optionally, the complexing agent is selected from citric acid and ethylene glycol, wherein the molar ratio of citric acid to ethylene glycol is (2-5):(0.5-2); Optionally, the temperature of the heat treatment is 80℃-150℃; Optionally, the heat treatment is carried out under stirring conditions; Optionally, the stirring rate is 100 rpm to 300 rpm; Optionally, the drying temperature is 250℃-400℃; Optionally, the drying process takes 2-10 hours. Optionally, the calcination temperature is 800℃-1200℃; Optionally, the calcination treatment time is 2h-20h.

9. A catalyst, characterized in that, Includes the oxide-loaded high-entropy alloy nanoparticle material according to any one of claims 1-3 or the oxide-loaded high-entropy alloy nanoparticle material prepared by the method according to any one of claims 4-8.

10. The oxide-supported high-entropy alloy nanoparticle material according to any one of claims 1-3, the oxide-supported high-entropy alloy nanoparticle material prepared by the method according to any one of claims 4-8, or the catalyst according to claim 9 has at least one of the following uses: Used as an active material in catalytic reactions; As an electrode material for electrocatalysis.

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