A high-entropy selenide electrode material and its preparation method and application

Abstract

This invention belongs to the technical field of high-entropy material preparation and electrocatalytic oxidation of glycerol, and discloses a high-entropy selenide electrode material, its preparation method, and its application. The method includes the following steps: S1, dissolving five soluble salts selected from cobalt, nickel, copper, manganese, iron, or molybdenum in a mixed solvent, sequentially adding copper foam and CTAB, followed by ultrasonication, and then reacting at 160–200°C to obtain a high-entropy selenide precursor; S2, mixing selenium powder with sodium borohydride to obtain a mixture, sequentially adding ethanol and the precursor to the mixture under a protective gas atmosphere, and then reacting at 160–200°C to obtain the high-entropy selenide electrode material. The high-entropy selenide electrode material prepared by this invention exhibits high selectivity for formate as an alkaline electrocatalyst for glycerol oxidation. When combined into an acid-base mixed electrolytic cell, it can simultaneously produce formate and hydrogen with only 0.5V, showing potential application value in organic-coupled hydrogen production.

Description

Technical Field

[0001] This invention belongs to the technical field of high-entropy material preparation and electrocatalytic oxidation of glycerol, specifically relating to a high-entropy selenide electrode material, its preparation method, and its application. Background Technology

[0002] The development of renewable and clean energy is significantly impacted by the depletion of fossil fuels and the implementation of new carbon emission control measures. Currently, electrocatalytic water splitting for the production of high-purity hydrogen has proven to be a simple, efficient, and easily scalable commercial technology. However, commercial electrolyzers typically require a decomposition voltage as high as 1.60V to 1.80V to produce hydrogen. This is primarily due to the sluggish kinetics of the oxygen evolution reaction (OER) at the anode. Currently, a more cost-effective hydrogen production strategy (with a lower decomposition voltage) has been successfully applied: electrocatalytic organic oxidation replacing the OER.

[0003] Recently, the use of electro-oxidized organic compounds, such as glucose, glycerates, urea, ethanol, and glycerol, to couple hydrogen evolution has been extensively studied. Glycerol, in particular, not only possesses a low theoretical oxidation potential but can also produce formate, a product required for direct formic acid fuel cells. Therefore, oxidizing glycerol to formate at the anode to replace the oxygen evolution reaction and coupling it to hydrogen production at the cathode becomes an ideal solution. However, due to the presence of three active hydroxyl groups, the oxidation process involves multiple parallel reactions in series. Glycerol is readily oxidized to various products, significantly reducing the yield of formate. Therefore, developing glycerol oxidation catalysts with high catalytic selectivity is of significant practical importance.

[0004] Electrolyzer system is another key factor in improving the efficiency of glycerol oxidative hydrogen production coupled with electrolysis. To date, electrolyzers used for glycerol oxidative hydrogen production still require relatively high decomposition potentials (0.7-1.5V) to achieve 10 mA·cm⁻¹. -2 The current density. Summary of the Invention

[0005] The purpose of this invention is to address the problem that existing electrolyzers used for glycerol oxidation coupled with hydrogen production still require relatively high decomposition potentials. This invention provides a high-entropy selenide electrode material, its preparation method, and its application, which maximizes the selectivity for formate during glycerol anodic oxidation. Simultaneously, it is assembled into an acid-base mixed electrolyzer to achieve the best water electrolysis for hydrogen production. The process equipment is simple, the production cost is low, and it is easy to implement on a large scale for industrial production and preparation, showing good industrialization prospects.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0007] The first objective of this invention is to provide a method for preparing a high-entropy selenide electrode material, comprising the following steps:

[0008] S1. Dissolve five soluble salts of cobalt, nickel, copper, manganese, iron or molybdenum in a mixed solvent. Add copper foam and CTAB to the mixed solvent in sequence and sonicate. Then react at 160-200℃. After the reaction is completed, cool, wash and dry to obtain the high-entropy selenide precursor.

[0009] S2. Selenium powder and sodium borohydride are mixed to obtain a mixture. Ethanol and the high-entropy selenide precursor obtained in S1 are added to the mixture in sequence under a protective gas atmosphere. The mixture is then reacted at 160-200℃. After the reaction is completed, the mixture is cooled, washed, and dried to obtain the high-entropy selenide electrode material.

[0010] Preferably, in S1, the molar percentage of any soluble salt is 5-80% of the sum of the molar percentages of the five soluble salts, and the sum of the molar percentages of the five soluble salts is 100%. The soluble salt is one of nitrate, chlorate, chloride, sulfate and ammonium salt.

[0011] Preferably, in S1, the molar volume ratio of the sum of the five soluble salts to the mixed solvent is 0.6 mmol: 18 mL, the mixed solvent is water and methanol, the volume ratio of water to methanol is 1:5, and the molar mass ratio of the sum of the five soluble salts to CTAB is 0.6 mmol: 0.25 g.

[0012] Preferably, in S1, the reaction time is 12 to 20 hours.

[0013] Preferably, in S2, the ratio of the high-entropy selenide precursor, selenium powder, sodium borohydride, and ethanol is: 1cm*2.5cm*0.1cm:0.06g:0.065g:18mL.

[0014] Preferably, in S2, the protective gas is N2 or Ar2, and the reaction time is 12-20 hours.

[0015] Preferably, in S1 and S2, the detergent used for washing is a mixture of water and ethanol, with a volume ratio of water to ethanol of 1:1, and the drying is vacuum drying at 60°C.

[0016] The second objective of this invention is to provide a high-entropy selenide electrode material prepared by the above-described preparation method. The high-entropy selenide electrode material has a layered structure, is loaded on copper foam, and has a width of 800–1000 nm and a thickness of 5–10 nm.

[0017] The third objective of this invention is to provide the application of the aforementioned high-entropy selenide electrode material in the highly selective electrocatalytic oxidation of glycerol to formic acid, and its assembly into an acid-base mixed-type electrolytic cell coupled with hydrogen evolution.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] (1) The high-entropy selenide electrode material synthesized in this invention exhibits excellent electrocatalytic oxidation performance of glycerol. The high-entropy selenide material has obvious lattice distortion, which is beneficial to fully utilizing the oxidation effect of each metal element. 1 ¹H NMR and HPLC results showed that the oxidation product of glycerol was only formate. In-situ infrared spectroscopy further revealed the oxidation process: glycerol was oxidized to glyceraldehyde, and glyceraldehyde was oxidized to glyceric acid. Glyceric acid was finally oxidized to formate. As a basic electrocatalyst, the oxidation of glycerol exhibited high selectivity for formate, thus improving the selectivity for formate during the anodic oxidation of glycerol.

[0020] (2) The addition of soluble salts of cobalt, nickel, copper, manganese, iron or molybdenum used in this invention helps to maximize the performance of each element while reducing costs, and further reduces the cost of hydrogen production in acid-base mixed electrolyzers.

[0021] (3) The present invention assembles an acid-base mixed electrolytic cell to achieve the best water electrolysis hydrogen production effect. The combined acid-base mixed electrolytic cell only requires a voltage of 0.5V to simultaneously prepare formate and hydrogen. It has potential application value in the direction of organic matter coupled hydrogen production. The process equipment is simple, the production cost is low, and it is easy to realize large-scale industrial production and preparation, with good industrialization prospects. Attached Figure Description

[0022] Figure 1 X-ray powder diffraction pattern of the high-entropy selenide product prepared in Example 1 of this invention;

[0023] Figure 2 This is a scanning electron microscope image of the high-entropy selenide product prepared in Example 1 of the present invention;

[0024] Figure 3 TEM, HRTEM, HAAD, STEM, and elemental mapping images of the high-entropy selenide product prepared in Example 1 of this invention;

[0025] Figure 4 XPS image of the high-entropy selenide product prepared in Example 1;

[0026] Figure 5 LSV curves of the high-entropy selenide product prepared in Example 1 of the present invention with and without 0.1 M glycerol in 1 MKOH;

[0027] Figure 6 The high-entropy selenide product prepared in Example 1 of this invention was oxidized in an electrolyte containing 0.1 M glycerol. 1 H-spectral NMR analysis;

[0028] Figure 7The high-entropy selenide product prepared in Example 1 of this invention was subjected to different oxidation potentials in an electrolyte containing 0.1 M glycerol. 1 H-spectral NMR analysis;

[0029] Figure 8 The high-entropy selenide product prepared in Example 1 of this invention was subjected to an ampere reaction at 10 mA·cm⁻¹. -2 Long-term stability plot at current density;

[0030] Figure 9 A schematic diagram and a comparison diagram of the water electrolysis performance of the high-entropy selenide product prepared in Example 1 of the present invention assembled with commercial Pt / C into an acid-base mixed electrolytic cell.

[0031] Figure 10 The stability diagram of the sample obtained in Example 1 of the present invention assembled with commercial Pt / C into an acid-base mixed electrolytic cell;

[0032] Figure 11 The diagram shows the microstructure, crystal structure, electrolysis cell device, and performance comparison with water electrolysis of the high-entropy selenide product prepared in Example 1 of this invention. Detailed Implementation

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the data in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] It should be noted that the technical terms used in this invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.

[0035] Example 1

[0036] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0037] S1. Preparation of the (CoNiCuMnMo)Se high-entropy selenide electrode material precursor: 0.12 mmol / L cobalt nitrate hexahydrate, 0.12 mmol / L nickel nitrate hexahydrate, 0.12 mmol / L copper nitrate trihydrate, 0.12 mmol / L manganese chloride tetrahydrate, and 0.12 mmol / L ammonium molybdate tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g of hexadecyltrimethylammonium bromide (CTAB) was added to the above solution and sonicated until all soluble salts were dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 180 °C for 20 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol at a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present. The (CoNiCuMnMo)Se high-entropy selenide electrode material precursor was obtained.

[0038] S2. Preparation of (CoNiCuMnMo)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL of ethanol was slowly added and the copper foam precursor obtained in step A was added. The mixture was transferred to a 20mL Teflon reactor and reacted at 180℃ for 16h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (CoNiCuMnMo)Se high-entropy selenide electrode material was washed three times with detergent and vacuum dried at 60℃ for 12h to obtain the (CoNiCuMnMo)Se high-entropy selenide electrode material.

[0039] Example 2

[0040] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0041] S1. Preparation of the (CoNiCuMnMo)Se high-entropy selenide electrode material precursor: 0.12 mmol / L cobalt nitrate hexahydrate, 0.12 mmol / L nickel nitrate hexahydrate, 0.12 mmol / L copper nitrate trihydrate, 0.12 mmol / L manganese chloride tetrahydrate, and 0.12 mmol / L ammonium molybdate tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g of hexadecyltrimethylammonium bromide was added to the above solution and sonicated until all soluble salts were dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 200 °C for 18 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol in a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present. The (CoNiCuMnMo)Se high-entropy selenide electrode material precursor was obtained.

[0042] S2. Preparation of (CoNiCuMnMo)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL of ethanol was slowly added, and the foamed copper precursor obtained in step A was added to it. The mixture was transferred to a 20mL Teflon reactor and reacted at 200℃ for 18h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (CoNiCuMnMo)Se high-entropy selenide electrode material was washed three times with detergent and dried under vacuum at 60℃ until no moisture was present.

[0043] Example 3

[0044] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0045] S1. Preparation of (CoNiFeCuMn)Se high-entropy selenide electrode material precursor: 0.12 mmol cobalt nitrate hexahydrate, 0.12 mmol nickel nitrate hexahydrate, 0.12 mmol ferric nitrate nonahydrate, 0.12 mmol copper nitrate trihydrate, and 0.12 mmol manganese chloride tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g hexadecyltrimethylammonium bromide was added to the above solution and sonicated until all soluble salts were dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 180 °C for 18 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol in a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present. The (CoNiFeCuMn)Se high-entropy selenide electrode material precursor was obtained.

[0046] S2. Preparation of (CoNiFeCuMn)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL of ethanol was slowly added and the foamed copper precursor obtained in step A was added. The mixture was transferred to a 20mL Teflon reactor and reacted at 180℃ for 18h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (CoNiFeCuMn)Se high-entropy selenide electrode material was washed three times with detergent and dried under vacuum at 60℃ until no moisture was present.

[0047] Example 4

[0048] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0049] S1. Preparation of (CoNiFeCuMo)Se high-entropy selenide electrode material precursor: 0.12 mmol / L cobalt nitrate hexahydrate, 0.12 mmol / L nickel nitrate hexahydrate, 0.12 mmol / L ferric nitrate nonahydrate, 0.12 mmol / L copper nitrate trihydrate, and 0.12 mmol / L ammonium molybdate tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g of hexadecyltrimethylammonium bromide was added to the above solution and sonicated until completely dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 180 °C for 20 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol in a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present. The (CoNiFeCuMo)Se high-entropy selenide electrode material precursor was obtained.

[0050] S2. Preparation of (CoNiFeCuMo)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL ethanol was slowly added and the foamed copper precursor obtained in step A was added. The mixture was transferred to a 20mL Teflon reactor and reacted at 180℃ for 20h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (CoNiFeCuMo)Se high-entropy selenide electrode material was washed three times with detergent and dried under vacuum at 60℃ until no moisture was present.

[0051] Example 5

[0052] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0053] S1. Preparation of the (CoNiFeMnMo)Se high-entropy selenide electrode material precursor: 0.12 mmol / L cobalt nitrate hexahydrate, 0.12 mmol / L nickel nitrate hexahydrate, 0.12 mmol / L ferric nitrate nonahydrate, 0.12 mmol / L manganese chloride tetrahydrate, and 0.12 mmol / L ammonium molybdate tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g of hexadecyltrimethylammonium bromide was added to the above solution and sonicated until completely dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 180 °C for 20 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol at a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present, thus obtaining the (CoNiFeMnMo)Se high-entropy selenide electrode material precursor.

[0054] S2. Preparation of (CoNiFeMnMo)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL of ethanol was slowly added, and the foamed copper precursor obtained in step A was added to it. The mixture was transferred to a 20mL Teflon reactor and reacted at 180℃ for 20h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (CoNiFeMnMo)Se high-entropy selenide electrode material was washed three times with detergent and dried under vacuum at 60℃ until no moisture was present.

[0055] Example 6

[0056] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0057] S1. Preparation of the (CoFeCuMnMo)Se high-entropy selenide electrode material precursor: 0.12 mmol / L cobalt nitrate hexahydrate, 0.12 mmol / L ferric nitrate nonahydrate, 0.12 mmol / L copper nitrate trihydrate, 0.12 mmol / L manganese chloride tetrahydrate, and 0.12 mmol / L ammonium molybdate tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g of hexadecyltrimethylammonium bromide was added to the above solution and sonicated until completely dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 180 °C for 20 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol in a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present. The (CoFeCuMnMo)Se high-entropy selenide electrode material precursor was obtained.

[0058] S2. Preparation of (CoFeCuMnMo)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL of ethanol was slowly added, and the foamed copper precursor obtained in step A was added to it. The mixture was transferred to a 20mL Teflon reactor and reacted at 180℃ for 20h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (CoFeCuMnMo)Se high-entropy selenide electrode material was washed three times with detergent and dried under vacuum at 60℃ until no moisture was present.

[0059] Example 7

[0060] A method for preparing a high-entropy selenide electrode material includes the following steps:

[0061] S1. Preparation of the (NiFeCuMnMo)Se high-entropy selenide electrode material precursor: 0.12 mmol nickel nitrate hexahydrate, 0.12 mmol ferric nitrate nonahydrate, 0.12 mmol copper nitrate trihydrate, 0.12 mmol manganese chloride tetrahydrate, and 0.12 mmol ammonium molybdate tetrahydrate were dissolved in a mixed solvent of 3 mL deionized water and 15 mL methanol. A 1 cm*2.5 cm*0.1 cm copper foam was added. 0.25 g hexadecyltrimethylammonium bromide was added to the above solution and sonicated until completely dissolved. After sonication, the solution was transferred to a 20 mL Teflon reactor and reacted at 180 °C for 20 h. After the reaction, the solution was cooled to room temperature. The obtained copper foam precursor was washed three times with detergent (deionized water and anhydrous ethanol in a volume ratio of 1:1) and dried under vacuum at 60 °C until no water was present. The (NiFeCuMnMo)Se high-entropy selenide electrode material precursor was obtained.

[0062] S2. Preparation of (NiFeCuMnMo)Se high-entropy selenide electrode material: 0.06g selenium powder and 0.065g sodium borohydride were mixed. Under the condition of purging with protective gas N2, 18mL of ethanol was slowly added, and the foamed copper precursor obtained in step A was added to it. The mixture was transferred to a 20mL Teflon reactor and reacted at 180℃ for 20h. After the reaction was completed, the mixture was cooled to room temperature. The obtained (NiFeCuMnMo)Se high-entropy selenide electrode material was washed three times with detergent and dried under vacuum at 60℃ until no moisture was present.

[0063] Figure 1 The X-ray powder diffraction pattern of the high-entropy selenide product prepared in Example 1 of this invention is shown below. Figure 1 As shown, obvious crystal diffraction peaks can be seen, corresponding to the cubic phase structure Cu2Se (JCPDS no. 88-2043). The uniform phase structure indicates that a high-entropy selenide with high crystallinity was successfully prepared.

[0064] Figure 2 This is a scanning electron microscope (SEM) image of the high-entropy selenide product prepared in Example 1 of this invention. Figure 2 In the diagram, a represents 1 μm, and b represents 300 nm. For example... Figure 2 As shown, the (CoNiCuMnMo)Se high-entropy selenide electrode material is a layered structure loaded on copper foam.

[0065] Figure 3 These are TEM, HRTEM, HAAD, STEM, and elemental mapping images of the high-entropy selenide product prepared in Example 1 of this invention. Figure 3 In the diagram, a represents TEM, b represents HRTEM, c represents HAAD, d represents STEM, and f represents element mapping. For example... Figure 3 As shown in Figure a, the morphology and microstructure of the product obtained in Example 1 were characterized by TEM. The results showed that the obtained (CoNiCuMnMo)Se high-entropy selenide electrode material sample had a sheet-like structure; HRTEM image ( Figure 3 Clear lattice fringes can be observed in b), where the lattice spacing of 0.324 nm corresponds to the (111) crystal plane, indicating that the prepared catalyst has good crystallinity; HAADF, STEM, and elemental mapping diagrams ( Figure 3 (cd) It can be seen that Co, Ni, Cu, Mn, Mo, and Se elements are uniformly distributed on the nanosheet.

[0066] Figure 4 This is the XPS image of the high-entropy selenide product prepared in Example 1 of this invention. Figure 4 In the diagram, a represents Co2p, b represents Ni2p, c represents Cu2p, d represents Mn2p, e represents Mo3d, and f represents Se3d. For example... Figure 4 As shown, Se-Co bonds can be identified in high-resolution Co2p spectra. Figure 4 a) where the peaks at 798.45 and 780.50 eV are attributed to Co, respectively. 2+ 2p 1 / 2 and Co 2+ 2p 3 / 2 The two distinct peaks in the Ni2p region correspond to Ni2p... 1 / 2 and Ni2p 3 / 2 Located at 873.50 and 856.45 eV, attributed to Ni 2+ ( Figure 4 b) The two peaks with binding energies of 952.01 and 932.15 eV correspond to Cu. + 2p 1 / 2 and Cu + 2p 3 / 2 The peaks at 953.75 and 933.95 eV are attributed to Cu, respectively. 2+ 2p 1 / 2 and Cu 2+ 2p 3 / 2 ( Figure 4 c) The other two peaks at 642.75 and 650.87 eV are from Mn in (CoNiCuMnMo)Se / CF. 4+ ( Figure 4 d) Mo3d region 3 / 2 and Mo3d 5 / 2 The binding energy Figure 4 The fitted values ​​at eV are 233.10 and 228.45 eV, indicating that Mo is in the +4 valence state; the other peak at 230.85 eV is Se3s, indicating divalent selenium (Se3s). 2-The presence of ) is confirmed by peaks in the Se3d region, with peaks at binding energies of 54.20 and 53.35 eV belonging to Se3d. 3 / 2 and Se3d 5 / 2 The broad peak at 59.15 eV is caused by the edge oxidation of Se, indicating the presence of SeO. x ( Figure 4 f).

[0067] Electrochemical performance testing was performed using a Shanghai Chenhua CHI760E electrochemical workstation, employing a three-electrode system. The reference electrode was an Hg / HgO electrode, the counter electrode was a platinum sheet electrode, and the working electrode was the prepared catalyst (1cm*1cm*0.1cm). The electrolyte was a 1M KOH + 0.1M glycerol solution. All potentials mentioned in the images and descriptions are based on the reversible hydrogen electrode as the standard.

[0068] Figure 5 The LSV curves of the high-entropy selenide product prepared in Example 1 of this invention are shown in 1 MKOH with and without 0.1 M glycerol. The product containing 0.1 M glycerol undergoes glycerol oxidation, while the product without 0.1 M glycerol undergoes oxygen evolution reaction. Figure 5 It can be seen that an electrolyte containing 0.1M glycerol can effectively reduce the oxidation potential, reaching 10 mA·cm at 1.2V. -2 The current density required to reach 10 mA·cm⁻¹ in an electrolyte without 0.1 M glycerol is 1.58 V. -2 The current density.

[0069] Figure 6 The high-entropy selenide product prepared in Example 1 of this invention was oxidized in an electrolyte containing 0.1 M glycerol. 1 H-spectrum NMR analysis. (See attached image.) Figure 6 As shown, the results indicate that formate is a product of glycerol oxidation.

[0070] Figure 7 The image shows the 1H NMR spectra of the high-entropy selenide product prepared in Example 1 of this invention at different oxidation potentials in an electrolyte containing 0.1 M glycerol. Figure 7 As shown, the results indicate that only formate is produced at different oxidation potentials.

[0071] Figure 8 The high-entropy selenide product prepared in Example 1 of this invention was subjected to an ampere reaction at 10 mA·cm⁻¹. -2 Long-term stability testing at current densities. For example... Figure 8 As shown, the results indicate that the (CoNiCuMnMo)Se high-entropy selenide electrode material can be maintained for 25 hours without performance degradation.

[0072] To further verify the catalytic performance of the (CoNiCuMnMo)Se high-entropy selenide electrode material from Example 1 for total water splitting, it was assembled with commercial Pt / C into an acid-base mixed-type electrolytic cell. The anode was the (CoNiCuMnMo)Se high-entropy selenide electrode material, and the electrolyte was a 1M KOH + 0.1M glycerol solution; the cathode was a 20% Pt / C electrode, and the electrolyte was a 0.5M H2SO4 solution.

[0073] Figure 9 This diagram shows a comparison of the high-entropy selenide product prepared in Example 1 of this invention with commercial Pt / C assembled into an acid-base mixed electrolytic cell and its water electrolysis performance. Figure 9 In the diagram, a is a schematic of the apparatus, and b is a comparison of the performance of water electrolysis. Figure 9 As shown, the results indicate that the (CoNiCuMnMo)Se high-entropy selenide electrode material, when assembled with commercial Pt / C into an acid-base mixed electrolytic cell, has significant advantages, requiring only 0.5V to achieve 10mA·cm⁻¹. -2 The current density.

[0074] Figure 10 This is a stability test of the sample obtained in Example 1 of the present invention, assembled with commercial Pt / C into an acid-base mixed electrolytic cell. For example... Figure 10 As shown, the (CoNiCuMnMo)Se high-entropy selenide electrode material, when assembled with commercial Pt / C into an acid-base mixed electrolytic cell, can remain stable for over 100 hours, during which the current density can be restored by adding new electrolyte.

[0075] Figure 11 The diagram shows the microstructure, crystal structure, electrolytic cell device, and performance comparison with water electrolysis of the high-entropy selenide product prepared in Example 1 of this invention. Figure 11 In the diagram, a is a schematic diagram of the microstructure of the high-entropy selenide product prepared in Example 1 of the present invention; b is a schematic diagram of the crystal structure of the high-entropy selenide product prepared in Example 1 of the present invention; c is a schematic diagram of an acid-base mixed electrolytic cell device assembled with the high-entropy selenide product prepared in Example 1 of the present invention and commercial Pt / C; d is a comparison diagram of the water electrolysis performance of the acid-base mixed electrolytic cell. Figure 11 As shown, the high-entropy selenide product prepared in Example 1 can achieve 10 mA cm⁻¹ at 0.5 V. -2 The current density is reduced by 1.126V compared to traditional electrolytic cells, resulting in a lower decomposition voltage.

[0076] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range, as well as any value between the two endpoints, can be selected. Since the steps and methods used are the same as in the implementation examples, preferred implementation examples are described here to avoid redundancy. Although preferred implementation examples of this invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these implementation examples. Therefore, the appended claims are intended to be interpreted as including the preferred implementation examples as well as all changes and modifications falling within the scope of this invention.

[0077] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for preparing a high-entropy selenide electrode material, characterized in that, Includes the following steps: S1. Dissolve five soluble salts of cobalt, nickel, copper, manganese, iron or molybdenum in a mixed solvent. Add copper foam and CTAB to the mixed solvent in sequence and sonicate. Then react at 160~200℃. After the reaction is completed, cool, wash and dry to obtain high-entropy selenide precursor. S2. Selenium powder and sodium borohydride are mixed to obtain a mixture. Ethanol and the high-entropy selenide precursor obtained in S1 are added to the mixture in sequence under a protective gas atmosphere. The mixture is then reacted at 160~200℃. After the reaction is completed, the mixture is cooled, washed, and dried to obtain the high-entropy selenide electrode material.

2. The method for preparing the high-entropy selenide electrode material according to claim 1, characterized in that, In S1, the molar percentage of any soluble salt is 5-80% of the sum of the molar percentages of the five soluble salts, and the sum of the molar percentages of the five soluble salts is 100%. The soluble salt is one of nitrate, chlorate, chloride, and sulfate.

3. The method for preparing the high-entropy selenide electrode material according to claim 1, characterized in that, In S1, the molar volume ratio of the sum of the five soluble salts to the mixed solvent is 0.6 mmol: 18 mL, the mixed solvent is water and methanol, the volume ratio of water to methanol is 1:5, and the molar mass ratio of the sum of the five soluble salts to CTAB is 0.6 mmol: 0.25 g.

4. The method for preparing the high-entropy selenide electrode material according to claim 1, characterized in that, In S1, the reaction time is 12-20 hours.

5. The method for preparing the high-entropy selenide electrode material according to claim 1, characterized in that, In S2, the ratio of the high-entropy selenide precursor, selenium powder, sodium borohydride, and ethanol is: 1cm*2.5cm*0.1cm:0.06g:0.065g:18mL.

6. The method for preparing the high-entropy selenide electrode material according to claim 1, characterized in that, In S2, the protective gas is N2 or Ar2, and the reaction time is 12-20 hours.

7. The method for preparing the high-entropy selenide electrode material according to claim 1, characterized in that, In S1 and S2, the washing agent used is a mixture of water and ethanol, with a volume ratio of water to ethanol of 1:1, and the drying is vacuum drying at 60°C.

8. A high-entropy selenide electrode material prepared by the preparation method according to any one of claims 1-7, characterized in that, The high-entropy selenide electrode material has a layered structure, which is loaded on copper foam. The width of the layered structure is 800-1000 nm and the thickness is 5-10 nm.

9. The application of the high-entropy selenide electrode material according to claim 8 in the highly selective electrocatalytic oxidation of glycerol to formic acid and its assembly into an acid-base mixed electrolytic cell coupled with hydrogen evolution.

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