High-entropy alloy nanoparticle catalyst, preparation method and application

Abstract

The invention discloses a high-entropy alloy nanoparticle catalyst as well as a preparation method and application thereof. According to the high-entropy alloy nanoparticle catalyst, high-entropy alloy nanoparticles comprise the following components in percentage by mole: 5 to 40 percent of platinum, 5 to 40 percent of palladium, 5 to 40 percent of gold, 5 to 40 percent of molybdenum and 5 to 40 percent of tungsten. The nano-particle catalyst has excellent electrochemical performance, can efficiently catalyze the water electrolysis hydrogen evolution reaction under acidic and alkaline conditions, and is low in overpotential and good in catalytic stability and durability when catalyzing the water electrolysis hydrogen evolution reaction.

Description

Technical Field

[0001] The present invention relates to the technical field of high-entropy alloys. More specifically, it relates to a high-entropy alloy nanoparticle catalyst, a preparation method thereof, and uses thereof. Background Art

[0002] With the increasing shortage of traditional resources and energy and the worsening environmental problems, the development of new energy has become the focus of the energy strategies of various countries. With the rise of hydrogen energy technology, the electrolytic water hydrogen evolution reaction supported by green electricity has become a key energy conversion technology, which can decompose water into hydrogen and oxygen through electrical energy. In this process, the design and performance of electrocatalysts are crucial for the reaction efficiency and economy. Traditional electrocatalysts are mainly based on noble metals such as platinum, but their expensive and limited resource nature restricts their large-scale application. Moreover, when traditional electrocatalysts are used to catalyze the electrolytic water hydrogen evolution reaction, their catalytic activity is usually significantly higher under acidic conditions than under alkaline conditions. However, when the active component of the catalyst is a non-noble metal, the non-noble metal may dissolve in the acidic environment, resulting in unstable catalytic performance and a significant decrease in activity.

[0003] High-entropy alloy materials are emerging materials with characteristics such as multi-element components, uniform distribution of each component, and abundant crystal defects, and they show potential advantages in the field of electrocatalysis. However, current high-entropy alloy materials are difficult to be used for the catalysis of the electrolytic water hydrogen evolution reaction, and the electrocatalytic performance of high-entropy alloy materials is not excellent enough, which limits their application in the field of the electrolytic water hydrogen evolution reaction. Summary of the Invention

[0004] The first technical problem to be solved by the present invention is to provide a high-entropy alloy nanoparticle catalyst. This nanoparticle catalyst has excellent electrochemical performance, can efficiently catalyze the electrolytic water hydrogen evolution reaction under acidic and alkaline conditions, and has a low overpotential, good catalytic stability and durability when catalyzing the electrolytic water hydrogen evolution chemical reaction.

[0005] The second technical problem to be solved by the present invention is to provide a preparation method of a high-entropy alloy nanoparticle catalyst.

[0006] The third technical problem to be solved by the present invention is to provide the use of a high-entropy alloy nanoparticle catalyst in the electrolytic water hydrogen evolution reaction.

[0007] To solve the first technical problem described above, the technical solution adopted by the present invention is as follows :

[0008] A high-entropy alloy nanoparticle catalyst, in terms of mole percentage, the high-entropy alloy nanoparticles include:

[0009] Platinum 5 - 35%,

[0010] Palladium 5 - 35%,

[0011] 5 - 35% gold,

[0012] 5 - 35% molybdenum, and

[0013] 5 - 35% tungsten.

[0014] As an embodiment, the particle size of the high - entropy alloy nanoparticles is 1 nm - 20 nm.

[0015] As an embodiment, the high - entropy alloy nanoparticles are crystalline, the structure of the crystal is a face - centered cubic crystal structure, and each metal element component exists in the form of an alloy.

[0016] As an embodiment, the high - entropy alloy nanoparticles include:

[0017] 5 - 35% platinum,

[0018] 5 - 35% palladium,

[0019] 5 - 35% gold,

[0020] 5 - 35% molybdenum, and

[0021] 5 - 35% tungsten.

[0022] To solve the second technical problem described above, the technical solution adopted by the present invention is as follows :

[0023] A method for preparing a high - entropy alloy nanoparticle catalyst, comprising the following steps:

[0024] 1) Dissolve platinum metal salt, palladium metal salt, rhodium metal salt, ruthenium metal salt, and tungsten metal salt in a solvent;

[0025] 2) Perform a hydrothermal reaction in the presence of a stabilizer and a reducing agent to obtain a nanoparticle colloid;

[0026] 3) Centrifuge the nanoparticle colloid to obtain a high - entropy alloy nanoparticle catalyst.

[0027] As an embodiment, in step 1), the platinum metal salt, palladium metal salt, gold metal salt, molybdenum metal salt, and tungsten metal salt are selected from one or more of chloropalladite, chloroplatinite, chlorides, or carbonyl salts of the corresponding metal elements.

[0028] As an embodiment, in step 1), the solvent is deionized water.

[0029] As an embodiment, in step 2), the reducing agent is triethylene glycol.

[0030] As an embodiment, in step 2), the stabilizer is polyvinylpyrrolidone.

[0031] As an implementation manner, in step 2), the temperature of the hydrothermal reaction is 210 - 230 °C.

[0032] As an implementation manner, in step 2), the time of the hydrothermal reaction is 0.5 - 1 hour.

[0033] To solve the third technical problem described above, the technical solution adopted by the present invention is as follows :

[0034] Use of the above-mentioned high-entropy alloy nanoparticle catalyst in the electrolytic water hydrogen evolution reaction. When the above-mentioned catalyst is used to catalyze the electrolytic water hydrogen evolution reaction, it can significantly reduce the overpotential, has good catalytic stability during long-term catalysis, and the overpotential will not increase after long-term catalysis.

[0035] Any range described in the present invention includes the end values, any numerical value between the end values, and any sub-range constituted by any numerical value between the end values or the end values.

[0036] Unless otherwise specified, each raw material in the present invention can be obtained by purchasing in the market, and the equipment used in the present invention can adopt conventional equipment in the field or be referred to the existing technology in the field.

[0037] Compared with the prior art, the present invention has the following beneficial effects :

[0038] 1) The high-entropy alloy nanoparticles of the present invention contain five specific types of metal elements. Since these five metal elements have relatively close chemical potentials and lattice parameters, they can form alloy nanoparticles, and can ensure that each metal component forms an alloy solid solution when being reduced. The five specific components produce a synergistic effect, which can provide multiple active sites for the electrolytic water hydrogen evolution process, greatly reducing the overpotential of electrolytic water hydrogen production. Moreover, the high mixing configurational entropy of these five components is beneficial to the formation of a stable single-phase solid solution structure, thereby improving the stability of the high-entropy alloy nanoparticles. When used as a catalyst, the catalyst can stably and durably provide high catalytic activity in both alkaline and acidic environments, and has high catalytic stability and durability. In the prior art, non-precious metal catalysts usually have difficulty in achieving good catalysis under acidic conditions.

[0039] 2) The catalyst of the present invention shows excellent performance in both alkaline and acidic electrolytic water hydrogen evolution reactions. Compared with the commercially available Pt / C catalyst in the prior art, the catalyst of the present invention not only has a lower overpotential and maintains stability in a long cycle, but also the preparation process of the active component high-alloy nanoparticles is simple and the conditions are mild, and can be prepared by a one-pot method. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The following further describes in detail the specific embodiments of the present invention with reference to the drawings.

[0041] Figure 1 is the XRD pattern of the high-entropy alloy nanoparticle electrocatalyst prepared in Example 1;

[0042] Figure 2 is the transmission electron microscope image of PtPdAuMoW obtained by the preparation method of Example 1;

[0043] Figure 3 is the sample element content of the ICP test of PtPdAuMoW obtained by the preparation method of Example 1;

[0044] Figure 4 is the electrochemical performance of the electrocatalyst obtained by the method of Example 1 and Pt / C (linear sweep voltammetry curve of hydrogen evolution reaction under alkaline conditions);

[0045] Figure 5 is the electrochemical performance of the electrocatalyst obtained by the method of Example 1 and Pt / C (linear sweep voltammetry curve of hydrogen evolution reaction under acidic conditions);

[0046] Figure 6 is the stability curve of the high-entropy alloy nanoparticle electrocatalyst obtained by the method of Example 1 during continuous hydrogen evolution reaction under N 2 saturated 1M KOH;

[0047] Figure 7 is the high-entropy alloy nanoparticle electrocatalyst prepared in Example 1 under N 2 saturated 0.5M H 2 SO 4 solution after 3000 cycles of CV cycling; linear sweep voltammetry curve;

[0048] Figure 8 is the high-entropy alloy nanoparticle electrocatalyst prepared in Example 1 under N 2 saturated 1M KOH solution after 3000 cycles of CV cycling; linear sweep voltammetry curve;

[0049] Figure 9 is the high-resolution EDS elemental mapping of the high-entropy alloy nanoparticles obtained by the preparation method of Example 1.

[0050] Figure 10 is the linear sweep voltammetry curve of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 1 before and after 3000 cycles of CV cycling in N2-saturated 1M KOH solution;

[0051] Figure 11 is the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 1 under N 2 saturated 0.5M H 2 SO 4 solution after 3000 cycles of CV cycling; linear sweep voltammetry curve;

[0052] Figure 12 are the linear sweep voltammetry curves of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 2 before and after 3000 cycles of CV in a N 2 saturated 1 M KOH solution;

[0053] Figure 13 are the linear sweep voltammetry curves of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 2 before and after 3000 cycles of CV in a N 2 saturated 0.5 M H 2 SO 4 solution;

[0054] Figure 14 are the linear sweep voltammetry curves of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 3 before and after 3000 cycles of CV in a N 2 saturated 1 M KOH solution;

[0055] Figure 15 are the linear sweep voltammetry curves of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 3 before and after 3000 cycles of CV in a N 2 saturated 0.5 M H 2 SO 4 solution;

[0056] Figure 16 are the linear sweep voltammetry curves of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 4 before and after 3000 cycles of CV in a N 2 saturated 1 M KOH solution;

[0057] Figure 17 are the linear sweep voltammetry curves of the high-entropy alloy nanoparticle electrocatalyst prepared in Comparative Example 4 before and after 3000 cycles of CV in a N 2 saturated 0.5 M H 2 SO 4 solution; Detailed Embodiments

[0058] To more clearly illustrate the present invention, the present invention will be further described below in conjunction with preferred embodiments and the accompanying drawings. Similar components in the drawings are denoted by the same reference numerals. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0059] Various cross-sectional views according to the disclosed embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, where certain details are enlarged for the purpose of clear expression, and certain details may be omitted. The shapes of various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art can additionally design regions / layers with different shapes, sizes, and relative positions according to actual requirements.

[0060] As an aspect of the present invention, a high-entropy alloy nanoparticle catalyst of the present invention, in mole percentage, comprises:

[0061] Platinum 5 - 40%,

[0062] Palladium 5 - 40%,

[0063] Gold 5 - 40%,

[0064] Molybdenum 5 - 40%, and

[0065] Tungsten 5 - 40%.

[0066] In the present invention, high entropy means that the configurational entropy S is greater than or equal to 1.5R, where R is the molar gas constant, and the configurational entropy is calculated by the following method where x represents the molar content of each component in the alloy. The configurational entropy S can represent the degree of disorder of a substance. Generally, the larger the configurational entropy, the higher the degree of disorder. The high-entropy alloy nanoparticles of the present invention have more than 5 different metal components, with a high degree of disorder and a large configurational entropy reaching the standard of high entropy.

[0067] Through research in this application, it is found that alloy nanoparticles composed of a specific combination of five metals, platinum (Pt), palladium (Pd), gold (Au), molybdenum (Mo), and tungsten (W), have excellent high-entropy effects. When used as the active metal component of an electrocatalyst, the electrocatalyst can have a low overpotential and good catalytic stability in the hydrogen evolution reaction of electrolyzed water.

[0068] As an implementation manner, the particle size of the high-entropy alloy nanoparticles is 1 nm - 20 nm.

[0069] As an implementation manner, the high-entropy alloy nanoparticles are crystals, and the structure of the crystals is a face-centered cubic crystal structure, and each metal element component exists in the form of an alloy solid solution.

[0070] As an implementation manner, the high-entropy alloy nanoparticles comprise:

[0071] Platinum 5 - 35%,

[0072] 5 - 35% palladium,

[0073] 5 - 35% gold,

[0074] 5 - 35% molybdenum, and

[0075] 5 - 35% tungsten.

[0076] As another aspect of the present invention, a method for preparing a high - entropy alloy nanoparticle catalyst of the present invention includes the following steps:

[0077] 1) Dissolve platinum metal salt, palladium metal salt, rhodium metal salt, ruthenium metal salt and tungsten metal salt in a solvent;

[0078] 2) Carry out a hydrothermal reaction in the presence of a stabilizer and a reducing agent to obtain a nanoparticle colloid;

[0079] 3) Centrifuge and separate the nanoparticle colloid to obtain a high - entropy alloy nanoparticle catalyst.

[0080] According to certain embodiments of the present invention, in step 1), the platinum metal salt, palladium metal salt, gold metal salt, molybdenum metal salt and tungsten metal salt are selected from one or more of palladium chlorite, platinum chlorite, chlorides or carbonyl salts of the corresponding metal elements.

[0081] According to certain embodiments of the present invention, in step 1), the solvent is deionized water.

[0082] According to certain embodiments of the present invention, in step 2), the reducing agent is triethylene glycol.

[0083] According to certain embodiments of the present invention, in step 2), the stabilizer is polyvinylpyrrolidone.

[0084] According to certain embodiments of the present invention, in step 2), the temperature of the hydrothermal reaction is 210 - 230 °C.

[0085] According to certain embodiments of the present invention, in step 2), the time of the hydrothermal reaction is 0.5 - 1 hour.

[0086] As yet another aspect of the present invention, the present invention provides the use of the above - mentioned high - entropy alloy nanoparticle catalyst in the electrolytic water hydrogen evolution reaction. When the above - mentioned catalyst is used to catalyze the electrolytic water hydrogen evolution reaction, it can significantly reduce the over - potential, has good catalytic stability during long - term catalysis, and the over - potential will not increase after long - term catalysis.

[0087] Example 1

[0088] A method for preparing PtPdAuMoW high - entropy alloy nanoparticles includes the following steps:

[0089] Taking the metal at 0.2 mmol equimolar as an example

[0090] 1) First, add 80.0 mg of K 2 PtCl 4 , 65 mg of K 2 PdCl 4 , 60 mg of AuCl 3 , 40 mg of Na 2 MoO 4 , 65 mg of Na 2 WO 4 to 40 ml of deionized water, and ultrasonically disperse for 20 - 40 minutes to obtain a metal precursor solution;

[0091] 2) Add 500 mg of PVP (polyvinylpyrrolidone) to a three - necked flask containing 300 ml of triethylene glycol, heat it in an oil bath to 230 °C, and inject the metal precursor solution into the triethylene glycol solution at a rate of 1.0 ml / min while continuously stirring the solution; continue heating for 15 minutes after injection and then stop heating;

[0092] 3) After the solution returns to room temperature, pour it into a beaker, extract with 200 ml each of diethyl ether and acetone for 10 h; centrifuge and wash four times with a solution of equal amounts of absolute ethanol and deionized water; place the material obtained after centrifugation and washing in a vacuum drying oven at 80 °C for 10 h to obtain a black solid powder; put the black solid powder into a tubular furnace for calcination, calcine at 500 °C for 2 h, and then continue to heat up to 700 °C for 1 h to obtain PtPdAuMoW high - entropy alloy nanoparticles.

[0093] The prepared PtPdAuMoW high - entropy alloy nanoparticles are used as electrocatalysts to test the electrocatalytic performance according to the following method. The steps are as follows:

[0094] First, use a mixed solvent of isopropanol and water in equal proportion to prepare the electrocatalyst into an ink, and then:

[0095] 1. Evaluation of catalytic performance under alkaline conditions:

[0096] Drop the electrocatalyst ink onto carbon paper. In a three - electrode system with 1 M KOH saturated with N 2 as the electrolyte, a mercury - mercury oxide electrode as the reference electrode, and a Pt sheet as the counter electrode, and the electrolytic cell is an H - type electrolytic cell. Evaluate the hydrogen evolution activity of the electrocatalyst for water electrolysis in an alkaline environment through the polarization curve. The scan rate is 5 mv / s. The results are as Figure 4 shown. Compare PdPtAuMoW with commercial Pt / C catalyst under the condition of the same metal usage amount.

[0097] Figure 4Shows the HER polarization curves of PdPtAuMoW and Pt / C. At a current density of 10 mA / cm 2 (normalized to the geometric area of the electrode), the overpotential of the commercial Pt / C catalyst is 12 mV, while that of the PdPtAuMoW catalyst is only 4 mV, indicating that PdPtAuMoW has good HER catalytic activity in an alkaline environment.

[0098] 2. Stability evaluation under alkaline conditions:

[0099] The stability of the PdPtAuMoW electrocatalyst in an alkaline environment was evaluated by chronopotentiometry at a constant current density of 10 mA / cm 2 for 168 hours and accelerated aging CV cycles. In a N 2 saturated 1 M solution, 3000 CV cycles were performed, and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 6 、 Figure 8 shown.

[0100] It can be seen that the PdPtAuMoW catalyst stably evolves hydrogen for up to 168 h in a N 2 saturated 1 M KOH electrolyte solution. After 3000 CV cycles, the polarization curve does not shift significantly negatively, indicating excellent stability.

[0101] 3. Catalytic performance evaluation under acidic conditions:

[0102] The electrocatalyst ink was drop-coated on carbon paper. In a three-electrode system with N 2 saturated 0.5 M H 2 SO 4 as the electrolyte, a mercurous sulfate electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell was an H-type electrolytic cell. The electrocatalytic activity of the electrocatalyst for hydrogen evolution in acidic electrolysis water was evaluated by polarization curves. The results are as Figure 5 shown.

[0103] It can be seen that at a current density of 10 mA / cm 2 (normalized to the geometric area of the electrode), the overpotential of the PdPtAuMoW catalyst is 6 mV, which is smaller than that of the Pt / C catalyst (a commonly used catalyst in the existing market) (16 mV). The PdPtAuMoW catalyst has excellent HER catalytic activity in acidic solutions.

[0104] 4. Stability evaluation under acidic conditions:

[0105] The stability of the PdPtAuMoW electrocatalyst in an acidic environment was evaluated by accelerated aging CV cycles. In a N 2 saturated 0.5 M H2 SO 4 3000 CV cycles were carried out in the solution, and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 7 shown.

[0106] It can be seen that after 3000 CV cycles, the polarization curve did not shift significantly negatively. At a current density of 10 mA / cm 2 (normalized to the geometric area of the electrode), the overpotential only increased to 9 mV, showing excellent stability.

[0107] The above PdPtAuMoW nanoparticles were characterized, and the characterization method is as follows:

[0108] 1. Crystal structure analysis:

[0109] The high-entropy alloy was confirmed to be single-phase nanoparticles with an FCC structure through X-ray diffraction images. The results are as Figure 1 shown. Compared with the diffraction peaks of Pt, Pd, and Au, the positions of the diffraction peaks of PtPdAuMoW nanoparticles shifted significantly, indicating that these elements were introduced into the nanostructure to form an alloy. The diffraction peak at around 40° corresponds to the (111) crystal plane, which has the highest diffraction intensity in the diffraction pattern, indicating that PtPdAuMoW nanoparticles are mainly composed of the (111) crystal plane. The broadened diffraction peak indicates its nanostructure characteristics.

[0110] 2. Morphology observation:

[0111] The particle size was observed using a transmission electron microscope, and the measured size was 1 - 20 nm. The results are as Figure 2 shown.

[0112] 3. Element distribution verification:

[0113] The uniform distribution of elements Pt, Pd, Au, Mo, and W on the nanostructure was determined by STEM energy-dispersive X-ray spectroscopy (EDS), indicating its alloy properties. The results are as Figure 9 shown.

[0114] 4. Component content determination:

[0115] The content of each element was measured by inductively coupled plasma atomic emission spectrometry (ICP-MS). The results are as Figure 3 shown. The molar ratio of each component of PtPdAuMoW nanoparticles was obtained as approximately Pt:Pd:Au:Mo:W = 31:27:24:13:5, which meets the range of 5% - 35% for the molar content of each component of the high-entropy alloy. Based on the above characterization results, it can be confirmed that PtPdRhRuCu high-entropy alloy nanoparticles were successfully synthesized.

[0116] Comparative Example 1

[0117] Repeat Example 1, except that the PtPdAuMoW high-entropy alloy nanoparticles are replaced with PdPtAuNiMn high-entropy alloy nanoparticles.

[0118] After testing,

[0119] Catalytic performance evaluation under alkaline conditions:

[0120] Drop the electrocatalyst ink on the carbon paper. In a three-electrode system with saturated 1M KOH as the electrolyte, a mercury-mercuric oxide electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell is an H-type electrolytic cell. Evaluate the hydrogen evolution activity of the electrocatalyst for water electrolysis in an alkaline environment through the polarization curve, with a scan rate of 5 mV / s. The results are as 2 shown: At a current density of 10 mA cm Figure 10 (normalized to the geometric area of the electrode), the overpotential of the PdPtAuNiMn catalyst is 37 mV. -2

[0121] 2. Stability evaluation under alkaline conditions

[0122] Evaluate the stability of the PdPtAuNiMn electrocatalyst in an acidic environment through accelerated aging CV cycles. Perform 3000 CV cycles in a saturated 1M solution of N 2 . Record the polarization curves of the catalyst before and after cycling. The results are as shown in Figure 10.

[0123] It can be seen from this that, compared with the initial state, the polarization curve of the PdPtAuNiMn catalyst shifts significantly negatively after 3000 activation cycles. At a current density of 10 mA / cm 2 , the initial overpotential is 37 mV, and the overpotential increases to 60 mV after 3000 activation cycles.

[0124] 3. Catalytic performance evaluation under acidic conditions:

[0125] Drop the electrocatalyst ink on the carbon paper. In a three-electrode system with saturated 0.5M H 2 SO 2 as the electrolyte, a mercurous sulfate electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell is an H-type electrolytic cell. Evaluate the hydrogen evolution activity of the electrocatalyst for water electrolysis in an acidic environment through the polarization curve. The results are as 4 shown. Figure 5

[0126] It can be seen from this that at a current density of 10 mA cm -2 (normalized to the geometric area of the electrode), the overpotential of the PdPtAuNiMn catalyst is 43 mV.

[0127] 4. Stability evaluation under acidic conditions:

[0128] The stability of the PdPtAuNiMn electrocatalyst in an acidic environment was evaluated by accelerated aging CV cycles. In an N 2 -saturated 0.5 M H 2 SO 4 solution, 3000 CV cycles were performed, and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 11 shown.

[0129] It can be seen that compared with the initial state, the polarization curve of the PdPtAuNiMn catalyst shifted significantly negatively after 3000 activation cycles. At a current density of 10 mA / cm 2 , the initial overpotential was 37 mV, and after 3000 activation cycles, the overpotential increased to 60 mV.

[0130] Comparative Example 2

[0131] Example 1 was repeated, except that the PtPdAuMoW high-entropy alloy nanoparticles were replaced with FeCoNiCuPt high-entropy alloy nanoparticles.

[0132] After testing

[0133] 1. Catalytic performance evaluation under alkaline conditions:

[0134] The electrocatalyst ink was drop-coated on carbon paper. In a three-electrode system with N 2 -saturated 1 M KOH as the electrolyte, a mercury / mercuric oxide electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell was an H-type electrolytic cell. The hydrogen evolution activity of the electrocatalyst in an alkaline environment was evaluated by the polarization curve, and the scanning rate was 5 mV / s. The results are shown in Figure 12. At a current density of 10 mA cm -2 (normalized to the geometric area of the electrode), the overpotential of the FeCoNiCuPt catalyst was 70 mV.

[0135] 2. Stability evaluation under alkaline conditions

[0136] The stability of the FeCoNiCuPt electrocatalyst in an acidic environment was evaluated by accelerated aging CV cycles. In an N 2 -saturated 1 M KOH solution, 3000 CV cycles were performed, and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 12 shown.

[0137] It can be seen that compared with the initial state, the polarization curve of the FeCoNiCuPt catalyst shifted significantly negatively after 3000 activation cycles. At a current density of 10 mA / cm 2, The initial overpotential is 70 mV, and after 3000 cycles of activation, the overpotential increases to 88 mV.

[0138] 3. Catalytic performance evaluation under acidic conditions:

[0139] Drop the electrocatalyst ink on the carbon paper, and in a three - electrode system with N 2 saturated 0.5 M H 2 SO 4 as the electrolyte, a mercurous sulfate electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell is an H - type electrolytic cell. Evaluate the hydrogen evolution activity of the electrocatalyst for water electrolysis in an acidic environment through polarization curves, and the results are as Figure 13 shown.

[0140] It can be seen from this that at a current density of 10 mA / cm 2 (normalized to the geometric area of the electrode), the overpotential of the FeCoNiCuPt catalyst is 66 mV.

[0141] 4. Stability evaluation under acidic conditions:

[0142] Evaluate the stability of the FeCoNiCuPt electrocatalyst in an acidic environment through accelerated - aging CV cycles. Perform 3000 CV cycles in a N 2 saturated 1 M solution, and record the polarization curves of the catalyst before and after cycling. The results are as Figure 13 shown.

[0143] It can be seen from this that compared with the initial state, the polarization curve of the FeCoNiCuPt catalyst shifts significantly negatively after 3000 cycles of activation. At a current density of 10 mA / cm 2 , the initial overpotential is 66 mV, and after 3000 cycles of activation, the overpotential increases to 74 mV.

[0144] Comparative Example 3

[0145] Repeat Example 1, the difference is that the reducing agent triethylene glycol is replaced with oleylamine. Take 80.0 mg K 2 PtCl 4 , 65 mg K 2 PdCl 4 , 60 mg AuCl 3 , 40 mg Na 2 MoO 4 , 65 mg Na 2 WO 4Oleylamine (5 mL) was added to a capped sample bottle. Then the sample bottle was ultrasonically treated for 30 minutes to obtain a transparent solution. It was heated from room temperature to 160 °C and then maintained at 160 °C for 8 h with stirring. The catalyst was collected by centrifugation and washed 3 times with cyclohexane / ethanol, and then naturally cooled to a certain temperature.

[0146] After testing,

[0147] 1. Catalytic performance evaluation under alkaline conditions:

[0148] The electrocatalyst ink was drop-coated on carbon paper. In a three-electrode system with 1 M KOH saturated with N 2 as the electrolyte, a mercury / mercuric oxide electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell was an H-type electrolytic cell. The electrocatalytic hydrogen evolution activity of the electrocatalyst in an alkaline environment was evaluated by polarization curves, and the scan rate was 5 mV / s. The results are as Figure 14 shown

[0149] At a current density of 10 mA cm-2 (normalized to the geometric area of the electrode), the overpotential of the PdPtAuMoW catalyst was 15 mV.

[0150] 2. Stability evaluation under alkaline conditions

[0151] The stability of the PdPtAuMoW electrocatalyst in an acidic environment was evaluated by accelerated aging CV cycles. 3000 CV cycles were carried out in a 1 M solution saturated with N2, and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 14 shown.

[0152] It can be seen that, compared with the initial state, the polarization curve of the PdPtAuMoW catalyst shifted significantly negatively after 3000 activation cycles. At a current density of 10 mA / cm 2 , the initial overpotential was 15 mV, and the overpotential increased to 33 mV after 3000 activation cycles.

[0153] 3. Catalytic performance evaluation under acidic conditions:

[0154] The electrocatalyst ink was drop-coated on carbon paper. In a three-electrode system with 0.5 M H 2 SO 4 saturated with N2 as the electrolyte, a mercurous sulfate electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell was an H-type electrolytic cell. The electrocatalytic hydrogen evolution activity of the electrocatalyst in an acidic environment was evaluated by polarization curves. The results are as Figure 15 shown.

[0155] It can be seen that at a current density of 10 mA / cm 2 , the overpotential of the PdPtAuMoW catalyst was 14 mV.

[0156] 4. Stability evaluation under acidic conditions:

[0157] The stability of the PdPtAuMoW electrocatalyst in an acidic environment was evaluated by accelerated aging CV cycles. 3000 CV cycles were carried out in a saturated 1 M solution of N 2 and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 15 shown.

[0158] It can be seen that compared with the initial state, the polarization curve of the PdPtAuMoW catalyst shifted significantly negatively after 3000 activation cycles. At a current density of 10 mA / cm 2 , the initial overpotential was 14 mV, and it increased to 23 mV after 3000 activation cycles.

[0159] Comparative Example 4

[0160] Example 1 was repeated, except that the stabilizer was replaced with benzyltriethylammonium chloride. An equimolar ratio of the salt and 600 mg of benzyltriethylammonium chloride (TEBA) were dissolved in 10 mL of TEG, stirred for 2 hours, then reacted at 230 °C for 1 hour. After cooling to room temperature, the product was washed several times with absolute ethanol and dried in vacuo for further use.

[0161] After testing,

[0162] 1. Catalytic performance evaluation under alkaline conditions:

[0163] The electrocatalyst ink was drop-coated on carbon paper. In a three-electrode system with a saturated 1 M KOH as the electrolyte, a mercury / mercuric oxide electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell was an H-type electrolytic cell. The electrocatalytic hydrogen evolution activity of the electrocatalyst in an alkaline environment was evaluated by polarization curves, with a scan rate of 5 mV / s. The results are as 2 shown Figure 16 at a current density of 10 mA / cm

[0164] 2 , the overpotential of the PdPtAuMoW catalyst was 13 mV.

[0165] 2. Stability evaluation under alkaline conditions

[0166] Figure 16 The stability of the PdPtAuMoW electrocatalyst in an acidic environment was evaluated by accelerated aging CV cycles. 3000 CV cycles were carried out in a saturated 1 M KOH solution of N 2 and the polarization curves of the catalyst before and after cycling were recorded. The results are as Figure 16 shown.

[0167] It can be seen that, compared with the initial state, the polarization curve of the PdPtAuMoW catalyst is significantly negatively shifted after 3,000 cycles of activation. At a current density of 10 mA / cm 2 , the initial overpotential is 13 mV, and the overpotential increases to 28 mV after 3,000 cycles of activation.

[0168] 3. Catalytic performance evaluation under acidic conditions:

[0169] Drop the electrocatalyst ink onto the carbon paper. In a three-electrode system with 0.5 M H 2 saturated with N 2 SO 4 as the electrolyte, a mercury sulfate electrode as the reference electrode, and a Pt sheet as the counter electrode, the electrolytic cell is an H-type electrolytic cell. Evaluate the hydrogen evolution activity of the electrocatalyst for water electrolysis in an acidic environment through the polarization curve. The results are as Figure 17 shown.

[0170] It can be seen that at a current density of 10 mA / cm 2 (normalized to the geometric area of the electrode), the overpotential of the PdPtAuMoW catalyst is 12 mV.

[0171] 4. Stability evaluation under acidic conditions:

[0172] Evaluate the stability of the PdPtAuMoW electrocatalyst in an acidic environment through accelerated aging CV cycles. Conduct 3,000 cycles of CV in a 1 M solution saturated with N2, and record the polarization curves of the catalyst before and after cycling. The results are as Figure 17 shown.

[0173] It can be seen that, compared with the initial state, the polarization curve of the PdPtAuMoW catalyst is significantly negatively shifted after 3,000 cycles of activation. At a current density of 10 mA / cm 2 , the initial overpotential is 12 mV, and the overpotential increases to 26 mV after 3,000 cycles of activation.

[0174] It can be seen that the catalyst prepared in Example 1 has a small overpotential and good stability. Compared with the 4 comparative examples, the performance is significantly better.

[0175] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation manners here. All obvious changes or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A high entropy alloy nanoparticle catalyst, characterized in that: In terms of molar percentage, the high entropy alloy nanoparticles include: Platinum 5-40%, Palladium 5-40%, Gold 5-40%, Molybdenum 5-40%, and Tungsten 5-40%.

2. The high entropy alloy nanoparticle catalyst according to claim 1, characterized in that: The particle size of the high entropy alloy nanoparticles is 1nm-20nm.

3. The high entropy alloy nanoparticle catalyst according to claim 1, characterized in that: The high entropy alloy nanoparticles are crystals, the structure of the crystals is a face-centered cubic crystal structure, and each metal element component exists in the form of an alloy.

4. The high entropy alloy nanoparticle catalyst according to claim 1, characterized in that: The high entropy alloy nanoparticles include: Platinum 5-35%, Palladium 5-35%, Gold 5-35%, Molybdenum 5-35%, and Tungsten 5-35%.

5. The method for preparing a high entropy alloy nanoparticle catalyst as claimed in any one of claims 1 to 4, characterized in that: The steps include: 1) dissolving a platinum metal salt, a palladium metal salt, a molybdenum metal salt, a gold metal salt and a tungsten metal salt in a solvent; 2) performing a hydrothermal reaction in the presence of a stabilizer and a reducing agent to obtain a nanoparticle colloid; 3) Centrifugally separating the nanoparticle colloid to obtain a high entropy alloy nanoparticle catalyst.

6. The method for preparing the high entropy alloy nanoparticle catalyst according to claim 5, characterized in that: In step 1), the platinum metal salt, palladium metal salt, gold metal salt, molybdenum metal salt and tungsten metal salt are selected from one or more of chloropalladium salt, chloroplatinite, chloride or carbonyl salt of the corresponding metal element.

7. The method for preparing the high entropy alloy nanoparticle catalyst according to claim 5, characterized in that: In step 1), the solvent is deionized water.

8. The method for preparing the high entropy alloy nanoparticle catalyst according to claim 5, characterized in that: In step 2), the reducing agent is triethylene glycol; preferably, in step 2), the stabilizing agent is polyvinyl pyrrolidone.

9. The method for preparing the high entropy alloy nanoparticle catalyst according to claim 5, characterized in that: In step 2), the temperature of the hydrothermal reaction is 210-230° C.; preferably, in step 2), the time of the hydrothermal reaction is 0.5-1 hour.

10. Use of the high entropy alloy nanoparticle catalyst as claimed in any one of claims 1 to 4 in hydrogen evolution reaction by electrolysis of water.

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