Multi-element alloy nano composite material as well as preparation method and application thereof

Abstract

The invention relates to a multi-component alloy nano composite material, the multi-component alloy nano composite material comprises a nano carbon material and alloy nano particles loaded on the nano carbon material, and the alloy nano particles are made of alloy at least comprising three metal elements, the metal element is any one of VIII group or IB group elements. According to the multi-element alloy nano composite material provided by the invention, the alloy nano particles are constructed through more than three metal elements, the alloy nano particles are loaded on the nano carbon material, and the catalytic activity of the alloy nano particles is greatly enhanced through an electronic effect among multi-component metals; therefore, the problem that an existing alloy nano material is not high in water electrolysis catalytic activity is solved.

Description

Technical Field

[0001] This application relates to the field of nanomaterials, and particularly to alloy nanomaterials. Background Art

[0002] In the field of hydrogen production by electrolyzing water, the active components of electrolyzed water catalysts are usually metal oxides, or single-metal nanoparticles containing one metal, or binary alloy nanomaterials containing two metals. Alloy materials with nanostructures have great potential for catalytic applications. Their excellent catalytic performance not only requires the electronic effects and synergistic effects between multiple metals, but also depends on the quantum size effect of the nanostructures. However, binary alloy nanomaterials have strong oxygen affinity, and the catalysts are easily oxidized and deactivated. This results in low electrolyzed water catalytic efficiency of existing binary alloy nanomaterials. Summary of the Invention

[0003] Embodiments of this application provide a multi-component alloy nanocomposite material, its preparation method and application to solve the technical problem of low electrolyzed water catalytic efficiency of existing alloy nanomaterials.

[0004] In a first aspect, embodiments of this application provide a multi-component alloy nanocomposite material, which includes a nanocarbon material and alloy nanoparticles loaded on the nanocarbon material. The material of the alloy nanoparticles is an alloy containing at least three metal elements, and the metal elements are elements of Group VIII or Group IB.

[0005] In some embodiments of this application, the metal element is any one of Pt, Au, Pd, Rh, and Ru.

[0006] In some embodiments of this application, the material of the alloy nanoparticles is an alloy composed of Pt, Au, Pd, Rh, and Ru.

[0007] In some embodiments of this application, in the alloy nanoparticles, the amounts of substances of Pt, Au, Pd, Rh, and Ru are the same.

[0008] In some embodiments of this application, the diameter of the alloy nanoparticles is 2 - 5 nm.

[0009] In some embodiments of this application, the nanocarbon material is any one of carbon nanoparticles, carbon nanotubes, graphene, or a mixed material of any at least two of them, or a composite material formed by any at least two of them being combined.

[0010] In some embodiments of this application, the nanocarbon material is carbon black.

[0011] In some embodiments of this application, calculated by mass percentage, the loading amount of the alloy nanoparticles on the nanocarbon material is 8% - 12%.

[0012] In a second aspect, an embodiment of the present application provides a method for preparing a multi - alloy nanocomposite material, the method comprising the following steps:

[0013] Disperse the nanocarbon material and precursors of at least three metals into a liquid comprising a reducing agent to form a first solution;

[0014] Perform ultrasonic treatment on the first solution to obtain a second solution;

[0015] Centrifuge the second solution to obtain a precipitate;

[0016] Wash, dry and then calcine the precipitate in an inert gas atmosphere to obtain the multi - alloy nanocomposite material,

[0017] wherein the constituent elements of the metal are any one of Group VIII or Group IB elements, and the valence state of the metal element in the precursor is a positive valence state.

[0018] In some embodiments of the present application, the precursor is any one of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, RhCl3.

[0019] In some embodiments of the present application, the step of dispersing the nanocarbon material and precursors of at least three metals into a liquid comprising a reducing agent is specifically:

[0020] Disperse the nanocarbon material, HAuCl4, H2PtCl6, K2PdCl4, RuCl3, RhCl3 into a liquid comprising a reducing agent.

[0021] In some embodiments of the present application, the amounts of substances of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, RhCl3 are the same.

[0022] In some embodiments of the present application, the nanocarbon material is any one of carbon nanoparticles, carbon nanotubes, graphene, or a mixed material of any at least two of them, or a composite material formed by any at least two of them combined.

[0023] In some embodiments of the present application, the nanocarbon material is carbon black.

[0024] In some embodiments of the present application, the total weight of the metal elements in the precursor is 8% - 12% of the nanocarbon material.

[0025] In some embodiments of the present application, the reducing agent is ethylene glycol.

[0026] In some embodiments of the present application, the liquid is ethylene glycol.

[0027] In some embodiments of the present application, during the ultrasonic treatment, the treatment duration is 5 to 15 minutes, and the frequency of the ultrasonic wave is 18 to 22 kHz.

[0028] In some embodiments of the present application, when washing the precipitate, the washing liquid used is a mixed solution obtained by mixing ethanol and acetone in a volume ratio of 1:10.

[0029] In some embodiments of the present application, the temperature of the roasting is 500 to 700 °C, and the time is 2 to 4 hours.

[0030] In a third aspect, an electrolyzed water catalyst is provided in an embodiment of the present application. The electrolyzed water catalyst includes the multi-component alloy nanocomposite material described in the first aspect, or the multi-component alloy nanocomposite material prepared by the method described in the second aspect.

[0031] The above technical solutions provided in the embodiments of the present application have the following advantages compared with the prior art:

[0032] The multi-component alloy nanocomposite material provided in the embodiments of the present application constructs alloy nanoparticles through three or more metal elements, loads the alloy nanoparticles onto the nano-carbon material, and greatly enhances the catalytic activity of the alloy nanoparticles through the electronic effect between the multi-component metals, thereby solving the problem of low electrolyzed water catalytic activity of the existing alloy nano-materials. Description of the Drawings

[0033] The drawings here are incorporated into the description and form a part of this description, showing embodiments consistent with the present application, and are used together with the description to explain the principles of the present application.

[0034] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0035] Figure 1 It is an XRD test diagram of the black solid in Example 1 of the present application and the multi-component alloy nanocomposite materials obtained in Examples 1 to 4;

[0036] Figure 2 It is a scanning transmission electron microscope diagram of the black solid and the multi-component alloy nanocomposite material in Example 1 of the present application;

[0037] Figure 3 It is a polarization curve diagram and a Tafel curve diagram of the multi-component alloy composite materials in Examples 1 to 3 of the present application and the Pt / C catalyst in Comparative Example 1. Detailed Embodiments

[0038] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0039] Unless otherwise specifically stated, the terms used in this article should be understood as having the meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used in this article have the same meaning as the general understanding of those skilled in the art to which this application belongs. In case of any conflict, this specification shall prevail.

[0040] Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment, etc. used in this application can be obtained through market purchases or can be prepared by existing methods.

[0041] Existing alloy nanomaterials have the technical problem of low electrolytic water catalytic efficiency.

[0042] The technical solutions provided by the embodiments of this application to solve the above technical problems are generally as follows:

[0043] In a first aspect, the embodiments of this application provide a multi-component alloy nanocomposite material, which includes a nanocarbon material and alloy nanoparticles supported on the nanocarbon material. The material of the alloy nanoparticles is an alloy containing at least three metal elements, and the metal elements are any one of Group VIII or Group IB elements.

[0044] It should be noted that the nanocarbon material described in this application refers to a carbon material with a nanoscale structure. The nanoscale can refer to the microscopic scale of the nanocarbon material itself, such as carbon nanoparticles with a nanoscale diameter, carbon nanorods or carbon nanowires with a nanoscale diameter, and common nanoscale carbon materials such as graphene and carbon nanotubes; or it can refer to a carbon material with a nanoscale microscopic structure, such as a carbon-based aerogel or carbon-based membrane with nanoscale pores.

[0045] In an alloy, there is an electronic effect between different metals that make up the alloy. As the number of metal types in the alloy increases, the resulting electronic effects become more diverse, generating the representative "cocktail effect" of high-entropy alloys, that is, the mutual combination of reaction sites can produce extremely optimized sites, and the catalytic activity is also more excellent.

[0046] This application constructs alloy nanoparticles with more than three metal elements, loads the alloy nanoparticles onto a nanocarbon material, and greatly enhances the stability of the alloy nanoparticles through the electronic effect between multi-component metals, thereby solving the problem of low electrocatalytic activity of existing alloy nanomaterials for water electrolysis.

[0047] In some embodiments of this application, the metal element is any one of Pt, Au, Pd, Rh, and Ru.

[0048] Pt, Au, Pd, Rh, and Ru themselves have good stability and water electrolysis catalytic ability, and it is easy to form alloys with each other.

[0049] In some embodiments of this application, the material of the alloy nanoparticles is an alloy composed of Pt, Au, Pd, Rh, and Ru.

[0050] A high-entropy alloy refers to an alloy formed by five or more metals in equal or approximately equal amounts. Benefiting from the strong electronic effect between multiple metals, high-entropy alloys composed of five or more metals have unique physical and chemical properties, perform well in aspects such as electrical conductivity, thermal conductivity, and corrosion resistance, and also have application potential in the field of electrocatalysis.

[0051] The beneficial effect of specifically selecting these five metals, Pt, Au, Pd, Rh, and Ru, to form the alloy nanoparticles in this application is to obtain more excellent catalytic stability than non-precious metal materials.

[0052] In some embodiments of this application, in the alloy nanoparticles, the amounts of substance of Pt, Au, Pd, Rh, and Ru are the same.

[0053] In some embodiments of this application, the diameter of the alloy nanoparticles is 2 - 5 nm.

[0054] In some embodiments of this application, the nanocarbon material is any one of carbon nanoparticles, carbon nanotubes, graphene, or a mixed material of any at least two of them, or a composite material formed by any at least two of them in combination.

[0055] As an example, the nanocarbon material can be one of carbon black, graphene powder, carbon nanotube powder, graphene-carbon nanotube composite film, and graphene-carbon black composite aerogel.

[0056] In some embodiments of this application, the nanocarbon material is carbon black.

[0057] The beneficial effect of selecting carbon black as the nanocarbon material is to obtain better electrical conductivity than other carbon materials.

[0058] In some embodiments of the present application, the loading amount of the alloy nanoparticles on the nano-carbon material is 8% to 12% by mass.

[0059] The beneficial effect of the alloy nanoparticles having a loading amount of 8% to 12% on the nano-carbon material is that, while ensuring a large loading amount and increasing the electrolytic water catalytic ability of the multi-element alloy nano-composite material, the alloy nanoparticles are not distributed too densely on the nano-carbon material and are not easy to agglomerate.

[0060] In a second aspect, the present invention provides a method for preparing a multi-component alloy nanocomposite material, the method comprising the following steps:

[0061] S1: dispersing nanocarbon material and at least three metal precursors into a liquid including a reducing agent to form a first solution;

[0062] S2: subjecting the first solution to ultrasonic treatment to obtain a second solution;

[0063] S3: centrifuging the second solution to obtain a precipitate;

[0064] S4: washing and drying the precipitate and then calcining it in an inert gas atmosphere to obtain the multi-element alloy nanocomposite material.

[0065] Wherein, the constituent element of the metal is any one of the elements of Group VIII or Group IB, and the valence state of the metal element in the precursor is positive.

[0066] It is easy to understand that the method described in the second aspect of the present application can be used to prepare the multi-component alloy nanocomposite material described in any embodiment of the first aspect.

[0067] Ultrasonic treatment can produce a cavitation effect, creating an instantaneous high-pressure and high-temperature environment at the microscopic scale, so that the positively valenced metal elements are reduced to metal elements by the reducing agent, and the metal atoms aggregate to form alloy balls of several nanometers.

[0068] The purpose of calcining is to further alloy the alloy pellets to form the alloy nanoparticles.

[0069] The present application ultrasonically treats a first solution containing a reducing agent and a precursor, and uses the cavitation effect generated by the ultrasonic treatment to reduce the positively valenced metal element in the precursor to a metal element by the reducing agent. The precursor can be quickly reduced to a metal element at room temperature, and the method has the advantages of being simple and fast.

[0070] In some embodiments of the present application, the precursor is any one of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3.

[0071] The above-mentioned precursors are reagents capable of stably preparing Pt, Au, Pd, Rh, and Ru, and the obtaining method is relatively simple, and they are easily reduced by a reducing agent under ultrasound.

[0072] In some embodiments of the present application, the dispersing the nanocarbon material and the precursors of at least three metals into a liquid including a reducing agent is specifically as follows:

[0073] S11: Disperse the nanocarbon material, HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 into a liquid including a reducing agent.

[0074] Based on the method of step S11, alloy nanoparticles composed of Pt, Au, Pd, Rh, and Ru can be prepared.

[0075] In some embodiments of the present application, the amounts of substances of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 are the same.

[0076] The amounts of substances of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 being the same can make the amounts of substances of Pt, Au, Pd, Rh, and Ru in the alloy nanoparticles the same.

[0077] In some embodiments of the present application, the nanocarbon material is any one of carbon nanoparticles, carbon nanotubes, and graphene, or any mixture of at least two of them, or a composite material formed by any at least two of them being combined.

[0078] As an example, the nanocarbon material can be one of carbon black, graphene powder, carbon nanotube powder, graphene-carbon nanotube composite film, and graphene-carbon black composite aerogel.

[0079] In some embodiments of the present application, the nanocarbon material is carbon black.

[0080] In some embodiments of the present application, the nanocarbon material is Vulcan XC-72.

[0081] In some embodiments of the present application, the total weight of the metal elements in the precursor is 8% - 12% of the nanocarbon material.

[0082] The total weight of the metal elements in the precursor being 8% - 12% of the nanocarbon material makes the loading amount of the alloy nanoparticles on the nanocarbon material 8% - 12%. The beneficial effect is that on the basis of ensuring a large loading amount and increasing the electrolytic water catalytic ability of the multi-component alloy nanocomposite material, the alloy nanoparticles are not too densely distributed on the nanocarbon material and are not easily agglomerated.

[0083] In some embodiments of the present application, the reducing agent is ethylene glycol.

[0084] Ethylene glycol has a relatively suitable reducing ability, which can not only quickly reduce the precursor, but also prevent the size of the alloy nanoparticles from being too large due to the overly violent reduction reaction.

[0085] In some embodiments of the present application, the liquid is ethylene glycol.

[0086] Ethylene glycol itself can be used as a solvent to disperse the precursor and the carbon nanomaterial. By dispersing the precursor and the carbon nanomaterial into ethylene glycol for reaction, alloy nanoparticles with a diameter of about 3 nm can be obtained.

[0087] In some embodiments of the present application, in the ultrasonic treatment, the treatment duration is 18 - 22 min, and the frequency of the ultrasonic wave is 18 - 22 kHz.

[0088] In some embodiments of the present application, when washing the precipitate, the washing liquid used for washing is a mixed solution obtained by mixing ethanol and acetone in a volume ratio of 1:10.

[0089] The beneficial effect of using the above-mentioned mixed solution as the washing liquid is to remove the organic matter on the surface of the nanoparticles and fully expose the active sites.

[0090] In some embodiments of the present application, the temperature of the calcination is 500 - 700 °C, and the time is 2 - 4 h.

[0091] In a third aspect, an electrolyzed water catalyst is provided in an embodiment of the present application. The electrolyzed water catalyst includes the multi-component alloy nanocomposite material described in the first aspect, or the multi-component alloy nanocomposite material prepared by the method described in the second aspect.

[0092] The electrolyzed water catalyst is realized based on the multi-component alloy nanocomposite material described in the first aspect or the multi-component alloy nanocomposite material prepared by the method described in the second aspect. The specific implementation manner of the electrolyzed water catalyst can refer to the embodiments of the first aspect or the second aspect. Since the electrolyzed water catalyst adopts some or all of the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated one by one here.

[0093] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application. For the experimental methods without specific conditions noted in the following embodiments, they are usually determined according to national standards. If there is no corresponding national standard, they are carried out according to general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0094] Example 1

[0095] This example provides a multi - alloy nanocomposite material, and the multi - alloy nanocomposite material is prepared by the following steps:

[0096] Sa: Dissolve 0.0044 mmol of each of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 into 10 mL of ethylene glycol, stir for 20 minutes after mixing to obtain solution A;

[0097] Sb: Dissolve 0.028 g of Vulcan XC - 72 carbon support into 30 mL of ethylene glycol, and perform ultrasonic treatment at room temperature for 20 minutes in an ultrasonic cleaner to obtain solution B;

[0098] Sc: Mix solution A and solution B in a 100 - mL beaker to obtain solution C;

[0099] Sd: Place the beaker containing solution C in an ultrasonic processor, put a cylindrical ultrasonic probe with a diameter of 1.5 cm into the beaker, the top of the probe is approximately at the middle position of the solution, the total ultrasonic time is 10 minutes, rest for 2 seconds every 10 seconds of work, the power of the ultrasonic processor is 750 watts and 20 kHz, and solution D is obtained after ultrasonic treatment;

[0100] Se: Centrifuge solution D at 8000 revolutions per minute to obtain a precipitate;

[0101] Sf: Wash the precipitate three times with 40 mL of a 1:10 mixed solution of ethanol and acetone, and dry it in a vacuum drying oven at 50 °C for 3 hours to obtain a black solid;

[0102] Sg: Calcinate the black solid at 700 °C in an N2 atmosphere for 2 hours to obtain the multi - alloy nanocomposite material.

[0103] Example 2

[0104] The difference between this example and Example 1 is only that:

[0105] Step Sa is: Dissolve 0.0044 mmol of each of HAuCl4, H2PtCl6, K2PdCl4, and RhCl3 into 10 mL of ethylene glycol, stir for 20 minutes after mixing to obtain solution A.

[0106] Specifically as follows:

[0107] This example provides a multi - alloy nanocomposite material, and the multi - alloy nanocomposite material is prepared by the following steps:

[0108] Sa: Dissolve 0.0044 mmol of HAuCl4, H2PtCl6, K2PdCl4, and RhCl3 each in 10 mL of ethylene glycol, mix them, and stir for 20 minutes to obtain Solution A;

[0109] Sb: Dissolve 0.024 g of Vulcan XC-72 carbon support in 30 mL of ethylene glycol, and ultrasonically treat it at room temperature in an ultrasonic cleaner for 20 minutes to obtain Solution B;

[0110] Sc: Mix Solution A and Solution B in a 100 mL beaker to obtain Solution C;

[0111] Sd: Place the beaker containing Solution C in an ultrasonic processor, put a cylindrical ultrasonic probe with a diameter of 1.5 cm into the beaker, and the top of the probe is approximately at the middle position of the solution. The total ultrasonic time is 10 minutes, with a 2-second break every 10 seconds of operation. The power of the ultrasonic processor is 750 watts and 20 kHz. After ultrasonic treatment, obtain Solution D;

[0112] Se: Centrifuge Solution D at 8000 revolutions per minute to obtain a precipitate;

[0113] Sf: Wash the precipitate three times with 40 mL of a 1:10 mixed solution of ethanol and acetone, and then dry it in a vacuum drying oven at 50 °C for 3 hours to obtain a black solid;

[0114] Sg: Calcinate the black solid at 700 °C in a nitrogen atmosphere for 2 hours to obtain the multi-alloy nanocomposite material.

[0115] Example 3

[0116] The difference between this example and Example 1 is only that:

[0117] Step Sa is: Dissolve 0.0044 mmol of HAuCl4, H2PtCl6, and K2PdCl4 each in 10 mL of ethylene glycol, mix them, and stir for 20 minutes to obtain Solution A.

[0118] Specifically as follows:

[0119] This example provides a multi-alloy nanocomposite material, and the multi-alloy nanocomposite material is prepared through the following steps:

[0120] Sa: Dissolve 0.0044 mmol of HAuCl4, H2PtCl6, and K2PdCl4 each in 10 mL of ethylene glycol, mix them, and stir for 20 minutes to obtain Solution A;

[0121] Sb: Dissolve 0.02 g of Vulcan XC-72 carbon support in 30 mL of ethylene glycol, and ultrasonically treat it at room temperature in an ultrasonic cleaner for 20 minutes to obtain Solution B;

[0122] Sc: Mix solution A and solution B in a 100 mL beaker to obtain solution C;

[0123] Sd: The beaker containing solution C is placed in an ultrasonic processor. A cylindrical ultrasonic probe with a diameter of 1.5 cm is placed in the beaker, and the top of the probe is approximately at the middle position of the solution. The total ultrasonic time is 10 minutes, with a 2 - second break every 10 seconds of operation. The power of the ultrasonic processor is 750 watts and 20 kHz. After ultrasonic treatment, solution D is obtained;

[0124] Se: Centrifuge solution D at 8000 revolutions per minute to obtain a precipitate;

[0125] Sf: Wash the precipitate three times with 40 mL of a 1:10 mixed solution of ethanol and acetone, and then dry it in a vacuum drying oven at 50 °C for 3 hours to obtain a black solid;

[0126] Sg: Calcine the black solid at 700 °C in a nitrogen atmosphere for 2 hours to obtain the multi - alloy nanocomposite material.

[0127] Example 4

[0128] The difference between this example and Example 1 is only that:

[0129] Step Sg is: Calcine the black solid at 500 °C in a nitrogen atmosphere for 2 hours to obtain the multi - alloy nanocomposite material.

[0130] Specifically as follows:

[0131] This example provides a multi - alloy nanocomposite material, and the multi - alloy nanocomposite material is prepared through the following steps:

[0132] Sa: Dissolve 0.0044 mmol of each of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 in 10 mL of ethylene glycol, mix and stir for 20 minutes to obtain solution A;

[0133] Sb: Dissolve 0.028 g of Vulcan XC - 72 carbon support in 30 mL of ethylene glycol, and ultrasonically treat it at room temperature for 20 minutes in an ultrasonic cleaner to obtain solution B;

[0134] Sc: Mix solution A and solution B in a 100 mL beaker to obtain solution C;

[0135] Sd: The beaker containing solution C was placed in an ultrasonic processor. A cylindrical ultrasonic probe with a diameter of 1.5 cm was placed in the beaker, and the top of the probe was approximately at the middle position of the solution. The total ultrasonic time was 10 minutes, with a 2 - second break every 10 seconds of operation. The power of the ultrasonic processor was 750 watts and 20 kHz. After ultrasonic treatment, solution D was obtained;

[0136] Se: Solution D was centrifuged at 8000 revolutions per minute to obtain a precipitate;

[0137] Sf: The precipitate was washed three times with 40 mL of a 1:10 mixed solution of ethanol and acetone, and then dried in a vacuum drying oven at 50 °C for 3 hours to obtain a black solid;

[0138] Sg: The black solid was calcined at 500 °C in an N2 atmosphere for 2 hours to obtain the multi - alloy nanocomposite material.

[0139] Comparative Example 1

[0140] This comparative example provides a commercial Pt / C catalyst with a loading of 20%.

[0141] Comparative Example 2

[0142] The difference between this comparative example and Example 1 is only that:

[0143] Step Sg was removed.

[0144] Specifically as follows:

[0145] This comparative example provides a multi - alloy nanocomposite material, which is prepared by the following steps:

[0146] Sa: 0.0044 mmol of each of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 was dissolved in 10 mL of ethylene glycol, and after mixing, it was stirred for 20 minutes to obtain solution A;

[0147] Sb: 0.028 g of Vulcan XC - 72 carbon support was dissolved in 30 mL of ethylene glycol and ultrasonically treated at room temperature for 20 minutes in an ultrasonic cleaner to obtain solution B;

[0148] Sc: Solution A and solution B were mixed in a 100 - mL beaker to obtain solution C;

[0149] Sd: The beaker containing solution C was placed in an ultrasonic processor. A cylindrical ultrasonic probe with a diameter of 1.5 cm was placed in the beaker, and the top of the probe was approximately at the middle position of the solution. The total ultrasonic time was 10 minutes, with a 2 - second break every 10 seconds of operation. The power of the ultrasonic processor was 750 watts and 20 kHz. After ultrasonic treatment, solution D was obtained;

[0150] Se: Centrifuge solution D at 8000 revolutions per minute to obtain a precipitate;

[0151] Sf: Wash the precipitate three times with 40 mL of a 1:10 mixed solution of ethanol and acetone, and then dry it in a vacuum drying oven at 50 °C for 3 hours to obtain the multi - alloy nanocomposite material.

[0152] Related experiments and effect data:

[0153] Perform XRD tests on the black solid obtained in step Sf of Example 1, and the multi - alloy nanocomposite materials obtained in Examples 1 - 3 and Example 8. The results are as Figure 1 shown.

[0154] From Figure 1 the XRD diffraction pattern, it can be found that the high - entropy alloy nanoparticles containing five metals exhibit a set of main peaks and a set of smaller additional peaks. These two sets of diffraction peaks are two face - centered cubic (FCC) crystal structures, indicating that the synthesized material has two phases. The black solid also exhibits the same characteristics. After the black solid is calcined at 500 °C and 700 °C for two hours in an N2 atmosphere, the intensity of the additional peaks significantly decreases, and the higher the calcination temperature, the more obvious it is. After calcination at 700 °C for two hours, the multi - alloy nanocomposite material provided in Example 1 is obtained, which has only one set of obvious and pure crystal diffractions, indicating that the synthesized material is a homogeneous alloy material.

[0155] In Examples 2 and 3, the multi - alloy nanocomposite materials were synthesized by the same method as in Example 1. Among them, a quaternary material was obtained in Example 2, and a ternary material was obtained in Example 3. It is worth noting that Example 3 still has the second - phase FCC structure after calcination, while Example 2 shows a pure single phase. This result indicates that increasing the number of metal types or increasing the degree of disorder (entropy value) of the system helps to form a homogeneous alloy phase.

[0156] Perform scanning transmission electron microscopy (STEM) tests on the black solid and the multi - alloy nanocomposite material in Example 1. The obtained results are shown in Figure 2 .

[0157] Among them, Figure 2 c is the HAADF image of the multi - alloy nanocomposite material obtained in Example 1, Figure 2 d, Figure 2 e, Figure 2 f, Figure 2 g, Figure 2 h are the EDS elemental scanning maps of Pt, Au, Pd, Rh, and Ru respectively.

[0158] From Figure 2Five elements can be seen to be uniformly distributed within the nanoparticles, which further proves that the nanoparticles are in a homogeneous alloy state. By counting, the nanoparticles in the black solid obtained in step Sf of Example 1, i.e., Comparative Example 2, are small balls with a diameter of 2.8 ± 0.3 nm, and the alloy nanoparticles in the multi-component alloy nanocomposite obtained by high-temperature calcination are small balls with a diameter of 2.6 ± 0.3 nm. This indicates that the high-entropy alloy has the ability to resist high-temperature sintering, and high-temperature treatment will not cause nanoparticle aggregation.

[0159] The electrocatalytic water splitting performance of the multi-component alloy composites of Examples 1 to 3 and the Pt / C catalyst of Comparative Example 1 was tested. The test was carried out in an electrochemical workstation using a standard three-electrode system, with Ag / AgCl (4M KCl) as the reference electrode and a platinum wire as the counter electrode. The test was carried out in a glass cell containing 200 mL of 1.0 M KOH solution as the electrolyte. The RHE potential was calculated by the formula E(RHE) = E(Ag / AgCl) + 0.0591 × pH + 0.195 V.

[0160] The method for fabricating the catalytic electrode is as follows: Dissolve 3 mg of the multi-component alloy nanocomposite or Pt / C catalyst in 900 μL of ethanol, then add 100 μL of Nafion. After ultrasonic treatment for 20 minutes, use a pipette to pick 20 μL of the suspension and vertically drop it onto a disk electrode with an area of 0.196 cm2, and then let it air-dry naturally in the air. The HER polarization curve was obtained by linear sweep voltammograms (LSVs) at a scanning rate of 5 mV / s and measured at a rate of 1600 rpm between voltages of 0–0.8 V (vs. Ag / AgCl). Before each measurement, the electrolyte was purged with N2 for 20 minutes to remove the internal oxygen.

[0161] The test results are as Figure 3 , where Figure 3 a is the polarization curve graph of the multi-component alloy composites of Examples 1 to 3 and the Pt / C catalyst of Comparative Example 1, Figure 3 b is the Tafel curve graph of the multi-component alloy composites of Examples 1 to 3 and the Pt / C catalyst of Comparative Example 1.

[0162] By comparing with the commercial Pt / C catalyst of Comparative Example 1 in Figure 3 a, the three alloy catalysts designed and synthesized in the present invention showed different catalytic activities for electrocatalytic hydrogen evolution (HER) from water splitting: Example 1 had the best performance, Example 2 was the second, and Example 3 was the worst. For Example 1, the initial potential of electrocatalytic hydrogen evolution was –0.025 V vs. RHE (vs. RHE means compared with the standard hydrogen electrode). When the current density reached 30 mA cm -2The required potential is only -0.19V vs. RHE. The initial potentials of the catalysts for electrocatalytic hydrogen evolution in Example 2 and Example 3 are also close to 0V vs. RHE, but the potentials required to reach a current density of 30 mA cm -2 are -0.26V vs. RHE and -0.6V vs. RHE respectively. Under the same test conditions, the performance of the commercial Pt / C catalyst is similar to that of the quaternary alloy catalyst, but significantly worse than that of the high-entropy alloy catalyst, indicating that the catalytic performance of the high-entropy alloy is very excellent. Of course, it should be noted that the loading of the commercial Pt / C catalyst is 20%, which is twice as high as that of Example 2 and Example 3. Therefore, their performance cannot be simply compared, but it can be undoubtedly considered that the catalytic performance of Example 1 is significantly higher than that of Comparative Example 1.

[0163] Figure 3 b shows the Tafel curves of Example 1-3 and Comparative Example 1. The Tafel curve is a function of potential - log|current density|. In alkaline electrolyte, the kinetic characteristics of the HER electrocatalytic hydrogen evolution reaction can be explained by the mechanism of the Volmer-Tafel two-step reaction. HER includes two steps: an electron-coupled dissociation of water molecules to form adsorbed hydrogen atoms (Volmer step); the combination of two adsorbed hydrogen atoms to form H2 (Tafel step). In alkaline solution, the HER reaction rate is usually slow due to the slow Volmer step. Therefore, accelerating the Volmer step is the key to accelerating the hydrogen evolution rate, and the slope of the Tafel curve reflects the speed of the Volmer step. A smaller Tafel slope indicates a lower Volmer reaction energy barrier and an easier Volmer step. The Tafel slope of Example 1 is 62 mV dec. -1 , which is less than 91 mV dec. of Example 2 -1 and 177 mV dec. of Example 3 -1 , and also less than that of the commercial Pt / C catalyst (77 mV dec. -1 ). A smaller Tafel slope means that the reaction energy barrier in the Volmer step is very low, so the HER electrocatalytic hydrogen evolution is easier to proceed, which also indicates the superiority of Example 1.

[0164] The various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be construed as a rigid limitation on the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and individual numbers within that range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0165] In the present application, unless otherwise stated, the orientation terms such as "upper" and "lower" specifically refer to the drawing directions in the drawings. Additionally, in the description of the present application specification, the terms "include", "comprise", etc. mean "including but not limited to". Moreover, the term "include", "comprise", or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or device including a series of elements not only includes those elements but also includes other elements not explicitly listed, or also includes elements inherent to such a process, method, article, or device. Without further limitation, elements defined by the statement "including..." do not exclude the existence of additional identical elements in the process, method, article, or device including the said elements. In this document, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this document, "and / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. For the association relationship of more than three associated objects described by "and / or", it means that these three associated objects can exist alone in any one item, or any at least two of them exist simultaneously. For example, for A, and / or B, and / or C, it can represent that any one of A, B, and C exists alone, or any two of them exist simultaneously, or all three of them exist simultaneously. In this document, "at least one" means one or more, and "multiple" means two or more. "At least one kind", "at least one item (piece) below", or similar expressions refer to any combination of these items, including any combination of single item (piece) or plural items (pieces). For example, "at least one item (piece) among a, b, or c", or, "at least one item (piece) among a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively.

[0166] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A multi-component alloy nanocomposite material, characterized in that, The multi-component alloy nanocomposite material includes a nanocarbon material and alloy nanoparticles supported on the nanocarbon material. The material of the alloy nanoparticles is an alloy comprising at least three metal elements, and the metal elements are elements of Group VIII or Group IB.

2. The multi-component alloy nanocomposite material according to claim 1, characterized in that, The metal element is any one of Pt, Au, Pd, Rh, and Ru.

3. The multi-component alloy nanocomposite according to claim 2, wherein, The material of the alloy nanoparticles is an alloy composed of Pt, Au, Pd, Rh, and Ru.

4. The multi-component alloy nanocomposite according to claim 3, wherein In the alloy nanoparticles, the amounts of substance of Pt, Au, Pd, Rh, and Ru are the same.

5. The multi-component alloy nanocomposite according to claim 1, characterized in that, The diameter of the alloy nanoparticles is 2 - 5 nm.

6. The multi-component alloy nanocomposite material according to claim 1, characterized in that, The nanocarbon material is any one of carbon nanoparticles, carbon nanotubes, and graphene, or a mixed material of any at least two of them, or a composite material formed by any at least two of them in combination.

7. The multi-component alloy nanocomposite according to claim 1, characterized in that, The nanocarbon material is carbon black.

8. The multi-component alloy nanocomposite according to claim 1, wherein By mass percentage, the loading amount of the alloy nanoparticles on the nanocarbon material is 8% - 12%.

9. A method for preparing a multi-component alloy nanocomposite material, characterized in that, The method includes the following steps: Disperse the nanocarbon material and precursors of at least three metals into a liquid including a reducing agent to form a first solution; Perform ultrasonic treatment on the first solution to obtain a second solution; Centrifuge the second solution to obtain a precipitate; Wash and dry the precipitate, and then calcine it in an inert gas atmosphere to obtain the multi-component alloy nanocomposite material, wherein the constituent elements of the metal are any one of the elements of Group VIII or Group IB, and the valence state of the metal element in the precursor is a positive valence state.

10. The preparation method of the multi-component alloy nanocomposite material according to claim 9, characterized in that, The precursor is any one of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3.

11. The method for preparing the multi-component alloy nanocomposite material according to claim 10, characterized in that, The step of dispersing the nanocarbon material and precursors of at least three metals into a liquid including a reducing agent specifically is: Disperse the nanocarbon material, HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 into a liquid including a reducing agent.

12. The preparation method of the multi-component alloy nanocomposite material according to claim 11, characterized in that, The amounts of substance of HAuCl4, H2PtCl6, K2PdCl4, RuCl3, and RhCl3 are the same.

13. The preparation method of the multi-component alloy nanocomposite material according to claim 9, characterized in that, The nanocarbon material is any one of carbon nanoparticles, carbon nanotubes, and graphene, or a mixed material of any at least two of them, or a composite material formed by any at least two of them in combination.

14. The preparation method of the multi-component alloy nanocomposite material according to claim 9, wherein, The nanocarbon material is carbon black.

15. The preparation method of the multi-component alloy nanocomposite material according to claim 9, characterized in that, The total weight of the metal element in the precursor is 8% - 12% of the nanocarbon material.

16. The preparation method of the multi-component alloy nanocomposite material according to claim 9, wherein, The reducing agent is ethylene glycol.

17. The preparation method of the multi-component alloy nanocomposite material according to claim 9, characterized in that, The liquid is ethylene glycol.

18. The method for preparing the multi-component alloy nanocomposite material according to claim 9, wherein, In the ultrasonic treatment, the treatment duration is 5 - 15 min, and the frequency of the ultrasonic wave is 18 - 22 kHz.

19. The preparation method of the multi-component alloy nanocomposite material according to claim 9, characterized in that, When washing the precipitate, the washing liquid used for washing is a mixed solution obtained by mixing ethanol and acetone in a volume ratio of 1:

10.

20. The preparation method of the multi-component alloy nanocomposite material according to claim 9, characterized in that, The temperature of the calcination is 500 - 700 °C, and the time is 2 - 4 h.

21. An electrolyzed water catalyst, characterized in that, The electrolytic water catalyst is the multi-component alloy nanocomposite material described in any one of claims 1 - 8, or the multi-component alloy nanocomposite material prepared by the method described in any one of claims 9 - 20.

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