Pt-based loaded high-entropy oxide, preparation method thereof and application of Pt-based loaded high-entropy oxide in seawater hydrogen production

Abstract

The invention relates to the technical field of catalysts of metal oxides, in particular to a Pt-based loaded high-entropy oxide, a preparation method thereof and application of the Pt-based loaded high-entropy oxide in seawater hydrogen production. Mixing a nickel precursor, an aluminum precursor, a ruthenium precursor, a chromium precursor, a cobalt precursor and water, and performing heat treatment to obtain sol; drying the obtained sol to obtain gel; calcining the obtained gel to obtain a high-entropy oxide precursor; and mixing the high-entropy oxide precursor with chloroplatinic acid, carrying out rotary evaporation drying, and carrying out high-temperature treatment to obtain the Pt-based loaded high-entropy oxide. The preparation raw materials are wide in source, the preparation process is simple, the consumed time is short, the preparation conditions are easy to accurately control, and the obtained catalyst is good in repeatability; the hydrogen production rate is superior to that of a commercial catalyst, and the long-term stability is excellent.

Description

Technical Field

[0001] The present invention relates to the technical field of metal oxide catalysts, and in particular to a Pt-based loaded high-entropy oxide, a preparation method thereof, and application thereof in hydrogen production from seawater. Background Art

[0002] Due to the increasing consumption of fossil fuels and the increasingly serious environmental problems, the development of clean and renewable energy is urgently needed for the sustainable development of human society. The generation of hydrogen by decomposing water molecules through water electrolysis can not only provide a sustainable source of hydrogen energy, but also reduce dependence on fossil energy. Traditional platinum-based catalysts play a key role in water electrolysis to produce hydrogen due to their high catalytic activity and excellent stability. However, the scarcity and high cost of platinum limit their large-scale application. Therefore, how to effectively reduce the amount of platinum while maintaining or improving catalytic performance has become an important issue in the field of energy conversion. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a Pt-based loaded high entropy oxide and its preparation method and application. The Pt-based loaded high entropy oxide prepared by the present invention not only reduces the amount of platinum used, but also maintains or improves its catalytic performance.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing a Pt-based supported high entropy oxide, comprising the following steps:

[0006] 1) mixing a nickel precursor, an aluminum precursor, a ruthenium precursor, a chromium precursor, a cobalt precursor and water, and heat-treating the mixture to obtain a sol;

[0007] 2) drying the sol obtained in step 1) to obtain a gel;

[0008] 3) calcining the gel obtained in step 2) to obtain a high entropy oxide precursor;

[0009] 4) The high entropy oxide precursor obtained in step 3) is mixed with chloroplatinic acid, dried by rotary evaporation, and then subjected to high-temperature treatment to obtain a Pt-based supported high entropy oxide.

[0010] Preferably, in step 1), the molar ratio of the nickel precursor, aluminum precursor, ruthenium precursor, chromium precursor and cobalt precursor is 1-2:1:0.2-1:1:1.

[0011] Preferably, the nickel precursor includes nickel nitrate hexahydrate, the aluminum precursor includes aluminum nitrate nonahydrate, the ruthenium precursor includes ruthenium chloride, the chromium precursor includes chromium nitrate nonahydrate, and the cobalt precursor includes cobalt nitrate hexahydrate.

[0012] Preferably, the drying conditions in step 2) include: drying under vacuum for 6 to 12 hours.

[0013] Preferably, the calcination conditions in step 3) include: a heating rate of 5° C. / min, a calcination temperature of 400-600° C., and a calcination time of 4 hours.

[0014] Preferably, in step 4), the volume ratio of the mass of the high entropy oxide precursor to chloroplatinic acid is 30 mg:0.9-1.8 mL.

[0015] Preferably, the conditions for the rotary evaporation drying in step 4) include: rotary evaporation at a temperature of 80° C. and a rotation speed of 135 rpm for 15 minutes.

[0016] Preferably, the conditions for the high temperature treatment in step 4) include: a heating rate of 5° C. / min, a high temperature treatment temperature of 400° C., and a high temperature treatment time of 3 h.

[0017] The present invention also provides a Pt-based loaded high entropy oxide prepared by the preparation method described in the above technical solution.

[0018] The present invention also provides the use of the Pt-based loaded high entropy oxide described in the above technical solution in hydrogen production.

[0019] The present invention loads platinum on high entropy oxides (HEOs), which can not only take advantage of the catalytic advantages of platinum, but also make use of the unique properties of high entropy oxides to achieve optimization of catalyst performance and reduction of cost.

[0020] Loading ultra-low platinum onto high-entropy oxides can significantly reduce the amount of platinum required without sacrificing catalytic performance. The interaction between platinum metal and the surface of the high-entropy oxide forms more dispersed platinum nanoparticles on the catalytic surface, increasing the number of effective platinum reaction sites. Furthermore, the multi-metallic nature of high-entropy oxides can optimize electronic and structural regulation during the reaction by adjusting the metal composition, further improving overall catalytic performance.

[0021] High-entropy oxides are a class of oxides composed of five or more metal elements with a high degree of elemental mixing and a complex crystal structure. They can effectively enhance the active sites on the catalytic surface and improve reaction activity by providing oxygen vacancies and other pathways.

[0022] Beneficial effects of the present invention:

[0023] 1. The raw materials for preparation are widely available, the preparation process is simple, the time consumption is short, the preparation conditions are easy to accurately control, and the obtained catalyst has good reproducibility.

[0024] 2. At the same current density, the overpotential of the catalyst of the present invention is significantly lower than that of the commercial catalyst Pt / C, and has excellent long-term stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below.

[0026] Figure 1 is the X-ray diffraction pattern of the Ru-based oxide hydrogen evolution catalyst;

[0027] Figure 2 is the X-ray diffraction pattern of the high entropy oxide supported Pt-based hydrogen evolution catalyst;

[0028] Figure 3 This is a high-resolution transmission electron microscopy image of a high-entropy oxide-supported Pt-based hydrogen evolution catalyst;

[0029] Figure 4 This is the scanning electron microscope elemental map of the high entropy oxide supported Pt-based hydrogen evolution catalyst;

[0030] Figure 5 is the linear scanning curve of Ru-based oxide hydrogen evolution catalyst;

[0031] Figure 6 is the linear scanning curve of the high entropy oxide supported Pt-based hydrogen evolution catalyst;

[0032] Figure 7 The high entropy oxide supported Pt-based hydrogen evolution catalyst was used at a current density of 300 mA / cm 2 Long-term stability test. DETAILED DESCRIPTION

[0033] The present invention provides a method for preparing a Pt-based supported high entropy oxide, comprising the following steps:

[0034] 1) mixing a nickel precursor, an aluminum precursor, a ruthenium precursor, a chromium precursor, a cobalt precursor and water, and heat-treating the mixture to obtain a sol;

[0035] 2) drying the sol obtained in step 1) to obtain a gel;

[0036] 3) calcining the gel obtained in step 2) to obtain a high entropy oxide precursor;

[0037] 4) The high entropy oxide precursor obtained in step 3) is mixed with chloroplatinic acid, dried by rotary evaporation, and then subjected to high-temperature treatment to obtain a Pt-based supported high entropy oxide.

[0038] The present invention mixes a nickel precursor, an aluminum precursor, a ruthenium precursor, a chromium precursor, a cobalt precursor, and water and heat-treats them to produce a sol. In the present invention, the molar ratio of the nickel precursor, aluminum precursor, ruthenium precursor, chromium precursor, and cobalt precursor is 1-2:1:0.2-1:1:1. In the present invention, the nickel precursor preferably comprises nickel nitrate hexahydrate, the aluminum precursor preferably comprises aluminum nitrate nonahydrate, the ruthenium precursor preferably comprises ruthenium chloride, the chromium precursor preferably comprises chromium nitrate nonahydrate, and the cobalt precursor preferably comprises cobalt nitrate hexahydrate. Aluminum has excellent stability, nickel and cobalt are widely used in electrocatalysis, ruthenium is less expensive than the precious metals platinum and palladium, and chromium acts as an activating catalyst in electrocatalysis. Therefore, the present invention uses these five elements as precursors for synthesizing high-entropy oxides. In the present invention, the water is preferably deionized water. The present invention preferably mixes the above raw materials under vigorous stirring and dissolves them in water. The present invention has no particular limitation on the heat treatment, as long as a sol is obtained after the treatment, for example, the treatment can be carried out in an oil bath heating condition to form a sol state.

[0039] The present invention is to dry the obtained sol to obtain a gel. In the present invention, the drying conditions preferably include: drying under vacuum -0.1 MPa, 60°C for 6 to 12 hours.

[0040] The present invention calcines the obtained gel to obtain a high entropy oxide precursor. In the present invention, the calcination conditions preferably include: a heating rate of 5°C / min, a calcination temperature of 400-600°C, and a calcination time of 4 hours.

[0041] The present invention mixes the obtained high entropy oxide precursor with chloroplatinic acid, and then performs high-temperature treatment after rotary evaporation and drying to obtain a Pt-based supported high entropy oxide. In the present invention, the volume ratio of the mass of the high entropy oxide precursor to chloroplatinic acid is preferably 30 mg:0.9~1.8 mL. In the present invention, the volume ratio of the mass of the high entropy oxide precursor to chloroplatinic acid is specifically 30 mg:0.9 mL, 30 mg:1.2 mL, 30 mg:1.5 mL and 30 mg:1.8 mL. In the present invention, the conditions for the rotary evaporation and drying preferably include: rotary evaporation at a temperature of 80 ° C and a rotation speed of 135 rpm for 15 minutes. In the present invention, the conditions for the high-temperature treatment preferably include: a heating rate of 5 ° C / min, a high-temperature treatment temperature of 400 ° C, and a high-temperature treatment time of 3 hours.

[0042] The present invention also provides a Pt-based loaded high entropy oxide prepared by the preparation method described in the above technical solution.

[0043] The present invention also provides the use of the Pt-based loaded high entropy oxide described in the above technical solution in hydrogen production.

[0044] In order to further illustrate the present invention, the present invention is described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0045] Example 1

[0046] This embodiment is an oxide with the molecular formula (RuCoAlCrNi)3O4, and the preparation method is as follows:

[0047] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 2:1:1:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0048] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then placing the formed sol under vacuum conditions of -0.1 MPa, 60°C, and 12 h to obtain a dry gel.

[0049] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable structure, thereby finally obtaining oxides.

[0050] HER measurements were performed in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat, maintaining the reaction temperature at a stable 25°C in a water bath. All tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of high-entropy oxide and thoroughly mixing 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of Nafion binder were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 minutes each, followed by drying in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating a 200 μL ink loading. The carbon cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0051] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0052] The XRD of the oxide in this example is as follows Figure 1 As shown by Figure 1 From the middle e-line, it can be seen that the diffraction peaks of the oxide in this embodiment correspond to the spinel cubic structure and the ruthenium oxide impurity peaks, and no single-phase solid solution structure is formed; its LSV performance is as follows Figure 4 As shown in line e, at a current density of 300 mA / cm 2 The overpotential cannot be detected at a current density of 10 mA / cm 2 The lower overpotential is 81mV; its stability can be stable for nearly 25 hours, and the stability effect is good.

[0053] Example 2

[0054] This embodiment is an oxide with the molecular formula (RuCoAlCrNi)3O4, and the preparation method is as follows:

[0055] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:1:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0056] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0057] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable structure, thereby finally obtaining oxides.

[0058] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0059] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0060] The XRD of the oxide in this example is as follows Figure 1 As shown by Figure 1 From the middle d line, it can be seen that the diffraction peaks of the high entropy oxide in this embodiment correspond to the spinel cubic structure and the peaks of ruthenium dioxide, and no single-phase solid solution structure is formed; its LSV performance is as follows Figure 5 As shown in line d, at a current density of 300 mA / cm 2 The overpotential cannot be detected at a current density of 10 mA / cm 2 The lower overpotential is 112mV; its stability can be stable for nearly 25 hours, and the stability effect is good.

[0061] Example 3

[0062] This embodiment is an oxide with the molecular formula (RuCoAlCrNi)3O4, and the preparation method is as follows:

[0063] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.5:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0064] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0065] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable structure, thereby finally obtaining oxides.

[0066] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0067] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0068] The XRD of the oxide in this example is as follows Figure 1 As shown by Figure 1 From the middle c line, it can be seen that the diffraction peaks of the high entropy oxide of this embodiment correspond to the spinel cubic structure and the mixed peaks of ruthenium dioxide, and no single-phase solid solution structure is formed; its LSV performance is as follows Figure 5 As shown in line c, at a current density of 300 mA / cm 2 The overpotential cannot be detected at a current density of 10 mA / cm 2 The lower overpotential is 136mV; its stability can be stable for nearly 25 hours, and the stability effect is good.

[0069] Example 4

[0070] This embodiment is an oxide with the molecular formula (RuCoAlCrNi)3O4, and the preparation method is as follows:

[0071] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.25:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0072] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0073] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable structure, thereby finally obtaining oxides.

[0074] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0075] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0076] The XRD of the oxide in this example is as follows Figure 1 As shown by Figure 1 As can be seen from the middle b line, the diffraction peaks of the oxide in this embodiment correspond to the spinel cubic structure and the nickel oxide miscellaneous peaks, and no single-phase solid solution structure is formed; its LSV performance is as follows Figure 4 As shown in line b, at a current density of 300 mA / cm 2 The overpotential cannot be detected at a current density of 10 mA / cm 2 The lower overpotential is 133mV; its stability can be stable for nearly 25 hours, and the stability effect is good.

[0077] Example 5

[0078] This embodiment is a Ru-based high entropy oxide with a molecular formula of (RuCoAlCrNi)3O4, and the preparation method is as follows:

[0079] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0080] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0081] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0082] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0083] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0084] The XRD pattern of the high entropy oxide in this embodiment is as follows: Figure 1 As shown by Figure 1 As can be seen from the middle a line, the diffraction peak of the high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Cr, Al, Ru, Co, and Ni elements; its LSV performance is as follows Figure 5 As shown in line a, at a current density of 300 mA / cm 2 The overpotential cannot be detected at a current density of 10 mA / cm 2 The lower overpotential is 15mV; its stability can be stable for nearly 25 hours.

[0085] This indicates that the catalyst of the present invention can form a single-phase solid solution structure at this ratio and has good hydrogen evolution performance, so Pt is loaded on the high entropy oxide precursor.

[0086] Example 6

[0087] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0088] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0089] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0090] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0091] 4) 0.9 mL of 4.76 g / L chloroplatinic acid solution was measured and thoroughly mixed with 30 mg of high entropy oxide precursor, stirred for 4 h, and the sample was rotary evaporated at 80 ° C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 ° C / min, a calcination temperature of 400 ° C, and a calcination time of 3 h.

[0092] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and a Hg / HgO (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of Nafion binder were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0093] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0094] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 As can be seen from the middle b line, the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; its LSV performance is as follows Figure 6 As shown in line a, at a current density of 300 mA / cm 2 The overpotential is 137mV, and the current density is 100mA / cm 2 The lower overpotential is 68mV; its stability can be stable for nearly 25 hours.

[0095] Example 7

[0096] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0097] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0098] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0099] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0100] 4) 1.2 mL of 4.76 g / L chloroplatinic acid solution was measured and thoroughly mixed with 30 mg of a high entropy oxide precursor, and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min, dried overnight, and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0101] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0102] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0103] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 As can be seen from the middle c line, the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; its LSV performance is as follows Figure 5 As shown in line b, at a current density of 300 mA / cm 2 The overpotential is 63mV and the current density is 100mA / cm 2 The lower overpotential is 34mV; its stability can be stable for nearly 25 hours, and the stability effect is good.

[0104] Example 8

[0105] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0106] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0107] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0108] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0109] 4) 1.5 mL of 4.76 g / L chloroplatinic acid solution was thoroughly mixed with 30 mg of a high-entropy oxide precursor and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0110] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0111] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0112] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The d line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; its LSV performance is as follows Figure 6 As shown in line c, at a current density of 300 mA / cm 2 The overpotential is 48mV and the current density is 100mA / cm 2The lower overpotential is 26mV; its stability can be stable for nearly 250 hours. The stability effect is very good and the stability will be improved as long as the electrolyte is replenished in time.

[0113] Example 9

[0114] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0115] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0116] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0117] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0118] 4) 1.8 mL of 4.76 g / L chloroplatinic acid solution was thoroughly mixed with 30 mg of a high entropy oxide precursor and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0119] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0120] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0121] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The middle e line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its LSV performance is as follows Figure 6 As shown in line d, at a current density of 300 mA / cm 2 The overpotential is 103mV and the current density is 100mA / cm 2 The lower overpotential is 41mV; its stability can be stable for nearly 25 hours, and the stability effect is good.

[0122] Example 10

[0123] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0124] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0125] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0126] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0127] 4) 1.5 mL of 4.76 g / L chloroplatinic acid solution was measured and thoroughly mixed with 30 mg of high entropy oxide precursor, stirred for 4 h, and the sample was rotary evaporated at 80 ° C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 ° C / min, a calcination temperature of 400 ° C, and a calcination time of 3 h.

[0128] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration with a CHI760E bipotentiostat. The tests were conducted in artificial seawater electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The Pt-based high-entropy ink drop-coated on carbon cloth was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, the carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited on the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the carbon cloth. The carbon cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0129] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0130] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The d line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; its LSV performance is as follows Figure 6 As shown by line f, at a current density of 300mA / cm 2 The overpotential is 47mV and the current density is 100mA / cm 2 The lower overpotential is 9mV; its stability can be stable for nearly 25 hours.

[0131] This indicates that the catalyst of the present invention still exhibits excellent hydrogen evolution performance in artificial seawater.

[0132] Example 11

[0133] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0134] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0135] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 6 hours to obtain a dry gel.

[0136] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0137] 4) 1.5 mL of 4.76 g / L chloroplatinic acid solution was thoroughly mixed with 30 mg of a high-entropy oxide precursor and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0138] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0139] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0140] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The d line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; at a current density of 300 mA / cm 2 The overpotential is 56mV and the current density is 100mA / cm 2 The lower overpotential is 37mV.

[0141] Example 12

[0142] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0143] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0144] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 8 hours to obtain a dry gel.

[0145] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0146] 4) 1.5 mL of 4.76 g / L chloroplatinic acid solution was thoroughly mixed with 30 mg of a high-entropy oxide precursor and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0147] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of a binder (Nafion) were added, and the ink was ultrasonicated for 60 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0148] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0149] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The d line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; at a current density of 300 mA / cm 2 The overpotential is 51mV and the current density is 100mA / cm 2 The lower overpotential is 30mV.

[0150] Example 13

[0151] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0152] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0153] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0154] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 400°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0155] 4) 1.5 mL of 4.76 g / L chloroplatinic acid solution was thoroughly mixed with 30 mg of a high-entropy oxide precursor and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0156] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of Nafion binder were added, and the ink was ultrasonicated for 20 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0157] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0158] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The d line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; at a current density of 300 mA / cm 2 The overpotential is 61mV, and the current density is 100mA / cm 2 The lower overpotential is 40mV.

[0159] Example 14

[0160] This embodiment is a Pt-based high entropy oxide with a molecular formula of Pt-(RuCoAlCrNi)3O4, and the preparation method is as follows:

[0161] 1) Under vigorous stirring, nickel, aluminum, ruthenium, chromium, and cobalt metal precursors were mixed with deionized water at a molar ratio of 1:1:0.2:1:1:444 and stirred until completely dissolved. The five metal precursors were nickel nitrate hexahydrate, aluminum nitrate nonahydrate, ruthenium chloride, chromium nitrate nonahydrate, and cobalt nitrate hexahydrate.

[0162] 2) Stirring the mixture in an oil bath until it becomes a sol state, and then vacuuming the formed sol for 12 hours to obtain a dry gel.

[0163] 3) The dried gel was calcined in air at a heating rate of 5°C / min, a calcination temperature of 500°C, and a calcination time of 4 hours. The five metal oxides had large configurational entropy and formed a stable single-phase crystal structure, ultimately obtaining a high-entropy oxide precursor.

[0164] 4) 1.5 mL of 4.76 g / L chloroplatinic acid solution was thoroughly mixed with 30 mg of a high-entropy oxide precursor and stirred for 4 h. The sample was rotary evaporated at 80 °C and 135 rpm for 15 min. The sample was dried overnight and subsequently calcined in air at a heating rate of 5 °C / min, a calcination temperature of 400 °C, and a calcination time of 3 h.

[0165] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration using a CHI760E bipotentiostat. The tests were conducted in 0.5 M H₂SO₄ electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a Pt-based high-entropy ink drop-coated on carbon cloth. The ink was prepared by weighing 7 mg of Pt-based high-entropy oxide and thoroughly mixing it with 3 mg of carbon powder. 965 μL of isopropyl alcohol and 35 μL of Nafion binder were added, and the ink was ultrasonicated for 40 min. Subsequently, a carbon cloth (1 cm × 2 cm) was washed in an ultrasonic bath with nitric acid, acetone, deionized water, and anhydrous ethanol for 30 min each, and then dried in an oven at 60°C overnight. The ink was evenly deposited onto the dry carbon cloth using a pipette, indicating that 200 μL of ink was loaded onto the cloth. The cloth was air-dried for 2 hours to obtain the working electrode for HER measurements.

[0166] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0167] The XRD pattern of the Pt-based high entropy oxide in this embodiment is as follows: Figure 2 As shown by Figure 2 The d line shows that the diffraction peak of the Pt-based high entropy oxide in this embodiment corresponds to the spinel cubic structure, forming a single-phase solid solution structure, which proves the successful synthesis of the Pt-based high entropy oxide; its TEM Figure 3 As shown, there is no obvious particle state; its EDS is as follows Figure 4 As shown, it represents the uniform distribution of Pt, Cr, Al, Ru, Co, and Ni elements; at a current density of 300 mA / cm 2 The overpotential is 52mV, and the current density is 100mA / cm 2 The lower overpotential is 29mV.

[0168] Comparative Example 1

[0169] In this embodiment, 20% of the commercial platinum-carbon catalyst was purchased from the TANAKA brand.

[0170] HER measurements were performed at room temperature in a standard three-electrode electrochemical cell in RDE configuration with a CHI760E bipotentiostat. The tests were performed in 0.5 M H2SO4 electrolyte using a Pt sheet counter electrode and an Ag / AgCl (saturated KCl) reference electrode. The working electrode was a 200 μL ink loaded onto dry carbon cloth, uniformly deposited using a pipette. The carbon cloth was then air-dried for 2 hours to obtain the working electrode for HER measurements.

[0171] Electrochemical testing was performed using cyclic voltammetry (CV) at a constant scan rate for 30 cycles to activate the catalyst until the signal stabilized. After docking the working electrode with the reference electrode, the open-circuit potential should fluctuate around 0 V, which can be used to verify open-circuit function. The catalyst was tested using LSV at a scan rate of 5 mV / s. Furthermore, the resulting voltage was iR-compensated to minimize the effects of resistance on the potential. At a given voltage, the change in current over time was measured to reflect catalyst stability.

[0172] Its LSV performance is as follows Figure 6 As shown in line e, at a current density of 300 mA / cm 2 Under the overpotential of 260mV, the current density is 103mA / cm 2 The high entropy oxide Pt-based hydrogen evolution electrocatalyst of the present invention has higher performance than commercial platinum-carbon catalysts and can effectively reduce energy consumption to produce hydrogen.

[0173] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A method for preparing a Pt-based supported high entropy oxide, characterized in that: The following steps are involved: 1) mixing a nickel precursor, an aluminum precursor, a ruthenium precursor, a chromium precursor, a cobalt precursor and water, and heat-treating the mixture to obtain a sol; 2) drying the sol obtained in step 1) to obtain a gel; 3) calcining the gel obtained in step 2) to obtain a high entropy oxide precursor; 4) The high entropy oxide precursor obtained in step 3) is mixed with chloroplatinic acid, dried by rotary evaporation, and then subjected to high-temperature treatment to obtain a Pt-based supported high entropy oxide.

2. The preparation method according to claim 1, characterized in that In the step 1), the molar ratio of the nickel precursor, the aluminum precursor, the ruthenium precursor, the chromium precursor and the cobalt precursor is 1-2:1:0.2-1:1:

1.

3. The preparation method according to claim 1 or 2, characterized in that The nickel precursor includes nickel nitrate hexahydrate, the aluminum precursor includes aluminum nitrate nonahydrate, the ruthenium precursor includes ruthenium chloride, the chromium precursor includes chromium nitrate nonahydrate, and the cobalt precursor includes cobalt nitrate hexahydrate.

4. The preparation method according to claim 1, characterized in that The drying conditions in step 2) include: drying under vacuum for 6 to 12 hours.

5. The preparation method according to claim 1, characterized in that The calcination conditions in step 3) include: a heating rate of 5° C. / min, a calcination temperature of 600° C., and a calcination time of 4 hours.

6. The preparation method according to claim 1, characterized in that In step 4), the volume ratio of the high entropy oxide precursor to chloroplatinic acid is 30 mg:0.9-1.8 mL.

7. The preparation method according to claim 1, characterized in that The conditions for the rotary evaporation drying in step 4) include: rotary evaporation at a temperature of 80° C. and a rotation speed of 135 rpm for 15 minutes.

8. The preparation method according to claim 1, characterized in that The conditions for the high temperature treatment in step 4) include: a heating rate of 5° C. / min, a high temperature treatment temperature of 400° C., and a high temperature treatment time of 3 hours.

9. A Pt-based supported high entropy oxide prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the Pt-based supported high entropy oxide according to claim 9 in hydrogen production from seawater.

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