AEMWE cathode electrode material under high current density and its large-scale preparation method and application

Abstract

The present invention provides an AEMWE cathode electrode material and a preparation method thereof. The AEMWE cathode electrode material provided by the present invention comprises: a metal foam substrate, a transition metal hydroxide formed on the surface of the metal foam substrate, and a modified metal nanosheet array deposited on the surface of the metal hydroxide. Among them, the intermediate layer metal hydroxide can promote proton-coupled electron transfer, induce metastable lattice distortion, and promote the formation of lattice dislocations / twins / distorted grain boundaries. At the same time, through the electric field or the electric field and magnetic field multi-field coupling, the controllable growth of nanosheets is achieved, the hydrogen evolution performance is effectively improved, and the charge transfer resistance is greatly reduced, and the hydrogen evolution performance and long-term stability of the catalytic material under high current density and industrial conditions are achieved. The AEMWE scheme provided by the present invention only requires 1.8V to achieve AEMWE water electrolysis hydrogen production under high current density, and stable operation for more than 1000h.

Description

Technical Field

[0001] The present invention belongs to the technical field of AEMWE (anion exchange membrane electrolysis of water), and relates to an AEMWE cathode electrode material and a preparation method and application thereof, and in particular to an AEMWE cathode electrode material under high current density and a large-scale preparation method and application thereof. Background Art

[0002] Hydrogen is clean, green, sustainable and has high energy density (about 10MJ / m 3 ) is considered a promising energy source. However, hydrogen still mainly comes from fossil fuels such as coal, oil and natural gas, which will bring a lot of carbon dioxide and environmental pollutants. Using solar or wind energy to electrolyze water as a green, clean and renewable way is considered a green way to produce hydrogen.

[0003] Water electrolysis consists of two half reactions: the cathode hydrogen evolution reaction (HER) and the anode oxygen evolution reaction (OER). Due to the sluggish kinetics of the HER and OER reactions, the two half reactions require a potential greater than the ideal equilibrium potential to generate H2 and O2. Therefore, overpotential is an important parameter that determines the performance of the catalyst. Generally, noble metal Pt and Ir / Rh material catalysts are regarded as excellent commercial catalysts for HER and OER. The preparation of green hydrogen by water electrolysis is one of the most promising technologies in the future, and it is expected to achieve efficient utilization of renewable energy scale and decarbonization. However, the usual water electrolysis methods require the use of platinum group precious metal materials (Ru, Rh, Pd, Ir, Pt), which have high hydrogen evolution catalytic activity, acid and alkali corrosion resistance and good reaction stability. Currently, most commercial catalysts are Pt / C. Due to the limited earth reserves and high cost of precious metal materials, they cannot be widely promoted and used in industrial production applications.

[0004] Among various water electrolysis technologies, the emerging anion exchange membrane water electrolysis (AEMWE) combines the advantages of alkaline water electrolysis (AWE) and proton exchange membrane water electrolysis (PEMWE). It has the characteristics of low cost, simplicity and high efficiency. In addition, this method can use non-precious metal catalysts and has great potential for commercial application. In recent years, a lot of research work has focused on the development of low-cost non-precious metal electrocatalysts. Ni, Co, Fe and Mo are the most widely used catalyst materials among transition metals. Due to their unique electronic structure, they are widely used by researchers in the design of water electrolysis catalysts. For example, the prior art patents CN114277396A and CN113856711A respectively designed Ni-Mo-based and Ni-Co-based water electrolysis cathode catalysts and applied them to the evaluation of water electrolysis performance. Under laboratory low current density tests, they all showed good hydrogen evolution performance. However, these catalysts have low operating current density (current density is usually less than 500mA / cm 2 ), short operating cycle, unable to meet the needs of industrial operation, etc. In addition, due to the limitations of scale-up and macro-quality preparation methods, these advanced non-precious metal catalysts are difficult to be truly commercially applied.

[0005] Therefore, multifunctional electrode materials (with characteristics such as large current, high activity and easy scale-up production) that can be applied to AEMWE under industrial conditions are crucial to promote the development of hydrogen energy from foundation to practical application. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide an AEMWE cathode electrode material and a preparation method and application thereof, in particular, an AEMWE cathode electrode material under high current density. The cathode electrode material for AEMWE under high current density provided by the present invention has excellent electrocatalytic hydrogen evolution performance, and the preparation method is simple, the conditions are mild, and it is green and environmentally friendly, and is more suitable for the promotion and application of industrial production.

[0007] The present invention provides an AEMWE cathode electrode material, comprising: a metal foam substrate, a transition metal hydroxide layer composited on the metal foam substrate, and a modified transition metal-based nanosheet array composited on the transition metal hydroxide layer;

[0008] The transition metal includes one or more of Co, Fe, Ni, Ce, Mn and Mo;

[0009] The modification includes one or more of phosphorus modification, sulfur modification and selenium modification.

[0010] Preferably, the transition metal hydroxide layer is specifically a transition metal hydroxide nanosheet array layer formed by longitudinally staggered growth;

[0011] The transition metal hydroxide layer has a clustered surface structure formed by staggered growth of nanosheets;

[0012] The thickness of the transition metal hydroxide nanosheet is 1 to 50 nm;

[0013] The transition metal hydroxide nanosheet has a sheet diameter of 10 nm to 10 μm;

[0014] A porous structure is formed between the nanosheets of the transition metal hydroxide layer;

[0015] The transition metal hydroxide layer is compounded in a manner including electrodeposition or electric field and magnetic field multi-field coupling deposition;

[0016] The thickness of the transition metal hydroxide layer is 10 nm to 20 μm;

[0017] The mass ratio of the metal foam substrate to the transition metal hydroxide layer is (1-10):1.

[0018] Preferably, the modified transition metal-based nanosheet array is staggered and composited on the transition metal hydroxide nanosheets in the transition metal hydroxide layer;

[0019] The modified transition metal-based nanosheet array has a cluster structure formed by staggered growth;

[0020] The thickness of the modified transition metal-based nanosheet is 1 to 50 nm;

[0021] The diameter of the modified transition metal-based nanosheet is 10 nm to 10 μm.

[0022] Preferably, a porous structure is formed between the nanosheets of the modified transition metal-based nanosheet array;

[0023] The transition metal elements in the modified transition metal-based nanosheets include the transition metal elements in the transition metal hydroxide layer and the transition metal elements added during the preparation of the modified transition metal-based nanosheets;

[0024] The modified transition metal-based nanosheet array composite method includes electrodeposition or electric field and magnetic field multi-field coupling deposition;

[0025] The thickness of the modified transition metal-based nanosheet array layer is 10 nm to 20 μm;

[0026] The modified transition metal-based nanosheets include one or more of transition metals, transition metal alloys and transition metal oxides, as well as modified transition metal compounds.

[0027] Preferably, the mass ratio of the metal foam substrate to the modified transition metal-based nanosheet array is (3-20):1;

[0028] The surface of the modified transition metal-based nanosheet is also compounded with modified transition metal-based nanoparticles;

[0029] The particle size of the modified transition metal-based nanoparticles is 1 to 50 nm;

[0030] The transition metal hydroxide layer and the modified transition metal-based nanosheet array have a topological structure of one or more of lattice dislocation, twinning and distorted grain boundary structure;

[0031] The AEMWE cathode electrode material includes cathode electrode materials of AEMWE for use under high current density conditions.

[0032] The present invention also provides a method for preparing an AEMWE cathode electrode material, comprising the following steps:

[0033] 1) placing a metal foam substrate in a soluble transition metal salt solution A as a working electrode, performing a first deposition under an electric field or an electric field and a magnetic field multi-field coupling and a nitrogen-rich atmosphere to obtain a metal foam substrate composited with a transition metal hydroxide layer;

[0034] 2) placing a soluble transition metal salt solution B in an electroplating tank, using the metal foam substrate composited with a transition metal hydroxide layer obtained in the above step as a working electrode, and performing a second deposition in an electric field or an electric field and a magnetic field multi-field coupling and a nitrogen-rich atmosphere to obtain a precursor;

[0035] 3) Under a protective atmosphere, the precursor and the modifier obtained in the above steps are heat treated to obtain the AEMWE cathode electrode material.

[0036] Preferably, the metal foam substrate comprises one or more of nickel foam, iron foam, cobalt foam, cobalt iron foam, nickel iron foam and nickel mesh;

[0037] The transition metals in the soluble transition metal salt solution A and the soluble transition metal salt solution B independently include one or more of Co, Fe, Ni, Ce, Mn and Mo;

[0038] The soluble transition metal salts in the soluble transition metal salt solution A and the soluble transition metal salt solution B independently include one or more of nitrates, sulfates, chlorides, carbonates, acetates, cyclopentaneates, stearates and neodecanoates of transition metals;

[0039] The soluble transition metal salt solution A and the soluble transition metal salt solution B are aqueous solutions, and the concentration of the transition metal is independently selected from 0.01 to 3.0 mol / L.

[0040] Preferably, the time of the first deposition and the second deposition are independently selected from 15 to 60 minutes;

[0041] The temperatures of the first deposition and the second deposition are independently selected from 20 to 50° C.;

[0042] The first deposition and the second deposition methods independently include one or more of constant potential deposition, constant current deposition, cyclic voltammetry and linear voltage scanning;

[0043] The first deposition and the second deposition are each specifically performed by using Hg / Hg2Cl2 or Ag / AgCl or Hg / HgO as a reference electrode and a platinum sheet / platinum wire / carbon rod as a counter electrode for deposition;

[0044] The magnetic field is added in a specific manner by adding magnets in a direction perpendicular to the electrode, and adjusting the magnetic field strength at the center of the magnetic field by changing the distance between the two groups of magnets;

[0045] The magnetic field strength is 0.01-3T.

[0046] Preferably, the modifier includes one or more of a sulfur source modifier, a selenium source modifier and a phosphorus source modifier;

[0047] The sulfur source modifier includes one or more of sulfur powder, thioacetamide, sodium sulfide and thiourea;

[0048] The selenium source modifier includes selenium powder and / or selenium dioxide;

[0049] The phosphorus source modifier includes one or more of potassium hypophosphite, potassium dihydrogen phosphate, red phosphorus and sodium hypophosphite;

[0050] The mass ratio of the transition metal-based nanosheets in the transition metal-based nanosheet array in the precursor to the mass ratio of the modifier is (1-2): (1-10);

[0051] The temperature of the heat treatment is 200-800°C;

[0052] The heat treatment time is 30 to 240 minutes;

[0053] The metal foam substrate is specifically a pretreated metal foam substrate.

[0054] The present invention also provides an AEMWE cathode electrode material as described in any one of the above technical solutions or an AEMWE cathode electrode material prepared by the preparation method as described in any one of the above technical solutions, and its application in the field of hydrogen production by anion exchange membrane water electrolysis and / or hydrogen production by alkaline water electrolysis.

[0055] The present invention provides an AEMWE cathode electrode material, comprising: a metal foam substrate, a transition metal hydroxide layer composited on the metal foam substrate, and a modified transition metal-based nanosheet array composited on the transition metal hydroxide layer; the transition metal comprises one or more of Co, Fe, Ni, Ce, Mn and Mo; the modification comprises one or more of phosphorus modification, sulfur modification and selenium modification. Compared with the prior art, the present invention provides an AEMWE cathode electrode material with a specific morphology and composition, and is a cathode electrode material that can be used for AEMWE at a high current density, and has the characteristics of high current, high activity and easy scale-up production. The present invention also provides a corresponding AEMWE cathode electrode material preparation method, through the electric field or electric field and magnetic field multi-field coupling, the controllable growth of nanosheets is achieved, and a modifier is used for high temperature modification to obtain a modified metal nanosheet material, the preparation method is simple and easy, and is suitable for industrialization and commercial promotion.

[0056] The AEMWE cathode electrode material provided by the present invention comprises an intermediate layer - a transition metal hydroxide. The highly active dissociation layer constructed by the intermediate layer is beneficial to breaking the H-OH bond, while reducing the loss of active sites during the hydrogen evolution reaction and accelerating the Volmer step. Moreover, the macroscopic magnetohydrodynamic effect and microscopic magnetohydrodynamic effect generated by the Lorentz force increase the liquid phase mass transfer rate, and the performance of the AEMWE cathode electrode material is improved by affecting various steps such as liquid phase mass transfer and electrode polarization during the deposition process.

[0057] The test results show that the AEMWE cathode electrode material provided by the present invention, in the membrane electrode (industrial pilot) test, with the homemade catalyst of this experiment as the anode (CN115404505A) and the Xiamen University Jiame as the anion exchange membrane, when the current is 4A, the battery voltage is 1.80V (commercial Pt / C||IrO2 is 1.87V), and can run stably for 1000h (test conditions: 1M KOH, 80℃, membrane electrode assembly size is 2*2cm 2 ). BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a SEM morphology image of Ni(OH)2 / NF prepared in Example 1 of the present invention;

[0059] Figure 2This is a SEM morphology image of CoFeCeP-Ni(OH)2 / NF prepared in Example 1 of the present invention;

[0060] Figure 3 The XRD spectrum of CoFeCeP-Ni(OH)2 / NF prepared in Example 1 of the present invention;

[0061] Figure 4 The figure is a graph showing the relationship between LSV, electrochemical impedance spectroscopy (EIS) and current density and time of the CoFeCeP-Ni(OH)2 / NF material prepared in Example 1 of the present invention;

[0062] Figure 5 This is the test curve of AEMWE assembled with the cathode material prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0063] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention rather than limiting the patent claims of the present invention.

[0064] All raw materials of the present invention have no particular limitation on their sources, and can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0065] There is no particular limitation on the purity of the raw materials used in the present invention, and the purity requirement of the raw materials for preparing the AEMWE cathode electrode material known to those skilled in the art may be sufficient.

[0066] The present invention provides an AEMWE cathode electrode material, comprising: a metal foam substrate, a transition metal hydroxide layer composited on the metal foam substrate, and a modified transition metal-based nanosheet array composited on the transition metal hydroxide layer;

[0067] The transition metal includes one or more of Co, Fe, Ni, Ce, Mn and Mo;

[0068] The modification includes one or more of phosphorus modification, sulfur modification and selenium modification.

[0069] In the present invention, the transition metal includes one or more of Co, Fe, Ni, Ce, Mn and Mo, and can be Co, Fe, Ni, Ce, Mn or Mo.

[0070] In the present invention, the modification includes one or more of phosphorus modification, sulfur modification and selenium modification, and can be phosphorus modification, sulfur modification and selenium modification.

[0071] In the present invention, the transition metal hydroxide layer is preferably an array layer formed by longitudinally staggered growth of transition metal hydroxide nanosheets.

[0072] In the present invention, the transition metal hydroxide layer preferably has a clustered surface structure formed by staggered growth of nanosheets.

[0073] In the present invention, the thickness of the transition metal hydroxide nanosheets is preferably 1 to 50 nm, more preferably 10 to 40 nm, and more preferably 20 to 30 nm.

[0074] In the present invention, the diameter of the transition metal hydroxide nanosheets is preferably 10 nm to 10 μm, more preferably 100 nm to 7 μm, and more preferably 1 to 4 μm.

[0075] In the present invention, a porous structure is preferably formed between the nanosheets of the transition metal hydroxide layer.

[0076] In the present invention, the composite method of the transition metal hydroxide layer preferably includes electrodeposition or electric field and magnetic field multi-field coupling deposition.

[0077] In the present invention, the thickness of the transition metal hydroxide layer is preferably 10 nm to 20 μm, more preferably 100 nm to 10 μm, and more preferably 1 to 2 μm.

[0078] In the present invention, the mass ratio of the metal foam substrate to the transition metal hydroxide layer is preferably (1-10):1, and more preferably (3-8):1.

[0079] In the present invention, the modified transition metal-based nanosheet array is preferably staggered and composited on the transition metal hydroxide nanosheets in the transition metal hydroxide layer. That is, the modified transition metal-based nanosheet array is staggered and disorderly superimposed on the transition metal hydroxide nanosheets in the transition metal hydroxide layer, rather than orderly coated or orderly deposited.

[0080] In the present invention, the modified transition metal-based nanosheet array preferably has a cluster structure formed by staggered growth.

[0081] In the present invention, the thickness of the modified transition metal-based nanosheets is preferably 1 to 50 nm, more preferably 10 to 40 nm, and more preferably 20 to 30 nm.

[0082] In the present invention, the diameter of the modified transition metal-based nanosheets is preferably 10 nm to 10 μm, more preferably 100 nm to 7 μm, and more preferably 1 μm to 4 μm.

[0083] In the present invention, a porous structure is preferably formed between the nanosheets of the modified transition metal-based nanosheet array.

[0084] In the present invention, the transition metal elements in the modified transition metal-based nanosheets preferably include the transition metal elements in the transition metal hydroxide layer and the transition metal elements added during the preparation of the modified transition metal-based nanosheets.

[0085] In the present invention, the modified transition metal-based nanosheet array composite method preferably includes electrodeposition or electric field and magnetic field multi-field coupling deposition.

[0086] In the present invention, the thickness of the modified transition metal-based nanosheet array layer is preferably 10 nm to 20 μm, more preferably 100 nm to 10 μm, and more preferably 1 to 2 μm.

[0087] In the present invention, the modified transition metal-based nanosheets preferably include one or more of transition metals, transition metal alloys and transition metal oxides, and modified transition metal compounds, more preferably multiple of transition metals, transition metal alloys and transition metal oxides, and modified transition metal compounds. Specifically, the modified transition metal compound may be one or more of transition metal sulfides and / or transition metal oxysulfides, transition metal phosphides and / or transition metal oxyphosphides, transition metal selenides and / or transition metal oxyselenides.

[0088] In the present invention, the mass ratio of the metal foam substrate to the modified transition metal-based nanosheet array is preferably (3-20):1, and more preferably (7-16):1.

[0089] In the present invention, the surface of the modified transition metal-based nanosheets is preferably compounded with modified transition metal-based nanoparticles.

[0090] In the present invention, the particle size of the modified transition metal-based nanoparticles is preferably 1 to 50 nm, more preferably 10 to 40 nm.

[0091] In the present invention, there is preferably a topological structure of one or more of lattice dislocation, twinning and distorted grain boundary structure between the transition metal hydroxide layer and the modified transition metal-based nanosheet array. That is, there is preferably a topological structure between the transition metal hydroxide layer and the modified transition metal-based nanosheet array. Specifically, the topological structure may be one or more of lattice dislocation, twinning and distorted grain boundary structure.

[0092] In the present invention, the cathode electrode material is preferably an integrated cathode electrode material having catalytic properties.

[0093] In the present invention, the AEMWE cathode electrode material preferably includes a cathode electrode material of AEMWE used in high current density conditions.

[0094] The present invention provides a method for preparing an AEMWE cathode electrode material, comprising the following steps:

[0095] 1) placing a metal foam substrate in a soluble transition metal salt solution A as a working electrode, performing a first deposition under an electric field or an electric field and a magnetic field multi-field coupling and a nitrogen-rich atmosphere to obtain a metal foam substrate composited with a transition metal hydroxide layer;

[0096] 2) placing a soluble transition metal salt solution B in an electroplating tank, using the metal foam substrate composited with a transition metal hydroxide layer obtained in the above step as a working electrode, and performing a second deposition in an electric field or an electric field and a magnetic field multi-field coupling and a nitrogen-rich atmosphere to obtain a precursor;

[0097] 3) Under a protective atmosphere, the precursor and the modifier obtained in the above steps are heat treated to obtain the AEMWE cathode electrode material.

[0098] The present invention first places a metal foam substrate in a soluble transition metal salt solution A as a working electrode, performs a first deposition under the action of an electric field or a multi-field coupling of an electric field and a magnetic field and a nitrogen-rich atmosphere, and obtains a metal foam substrate composited with a transition metal hydroxide layer.

[0099] In the present invention, the metal foam substrate preferably includes one or more of nickel foam, iron foam, cobalt foam, cobalt-iron foam, nickel-iron foam and nickel mesh, more preferably nickel foam, iron foam, cobalt foam, cobalt-iron foam, nickel-iron foam or nickel mesh.

[0100] In the present invention, the transition metals in the soluble transition metal salt solution A and the soluble transition metal salt solution B each independently preferably include one or more of Co, Fe, Ni, Ce, Mn and Mo, more preferably Co, Fe, Ni, Ce, Mn or Mo.

[0101] In the present invention, the soluble transition metal salts in the soluble transition metal salt solution A and the soluble transition metal salt solution B preferably independently include one or more of nitrates, sulfates, chlorides, carbonates, acetates, cyclopentaneates, stearates and neodecanoates of transition metals, and more preferably nitrates, sulfates, chlorides, carbonates, acetates, cyclopentaneates, stearates or neodecanoates of transition metals.

[0102] The present invention then places the soluble transition metal salt solution B in an electroplating tank, uses the metal foam substrate composited with a transition metal hydroxide layer obtained in the above steps as a working electrode, and performs a second deposition under the action of an electric field or a multi-field coupling of an electric field and a magnetic field and a nitrogen-rich atmosphere to obtain a precursor.

[0103] In the present invention, the soluble transition metal salt solution A and the soluble transition metal salt solution B are aqueous solutions, and the concentration of the transition metal is independently preferably selected from 0.01 to 3.0 mol / L.

[0104] In the present invention, the time of the first deposition and the second deposition are each independently preferably selected from 15 to 60 minutes.

[0105] In the present invention, the temperatures of the first deposition and the second deposition are each independently preferably selected from 20 to 50°C, more preferably 25 to 45°C.

[0106] In the present invention, the first deposition and the second deposition methods each independently preferably include one or more of constant potential deposition, constant current deposition, cyclic voltammetry and linear voltage scanning, more preferably constant potential deposition, constant current deposition, cyclic voltammetry or linear voltage scanning.

[0107] In the present invention, the first deposition and the second deposition are each preferably carried out using Hg / Hg2Cl2 or Ag / AgCl or Hg / HgO as a reference electrode and a platinum sheet / platinum wire / carbon rod as a counter electrode.

[0108] In the present invention, the method of adding the magnetic field is preferably to add magnets in a direction perpendicular to the electrodes, and to adjust the magnetic field strength at the center of the magnetic field by changing the distance between the two groups of magnets.

[0109] In the present invention, the magnetic field strength is preferably 0.01-3T.

[0110] Finally, in the present invention, the precursor and the modifier obtained in the above steps are subjected to heat treatment under a protective atmosphere to obtain the AEMWE cathode electrode material.

[0111] In the present invention, the modifier preferably includes one or more of a sulfur source modifier, a selenium source modifier and a phosphorus source modifier, and more preferably a sulfur source modifier, a selenium source modifier or a phosphorus source modifier.

[0112] In the present invention, the sulfur source modifier preferably includes one or more of sulfur powder, thioacetamide, sodium sulfide and thiourea, and more preferably includes sulfur powder, thioacetamide, sodium sulfide or thiourea.

[0113] In the present invention, the selenium source modifier preferably includes selenium powder and / or selenium dioxide, and more preferably selenium powder or selenium dioxide.

[0114] In the present invention, the phosphorus source modifier preferably includes one or more of potassium hypophosphite, potassium dihydrogen phosphate, red phosphorus and sodium hypophosphite, and more preferably potassium hypophosphite, potassium dihydrogen phosphate, red phosphorus or sodium hypophosphite.

[0115] In the present invention, the mass ratio of the transition metal-based nanosheets in the transition metal-based nanosheet array in the precursor to the mass ratio of the modifier is preferably (1-2):(1-10).

[0116] In the present invention, the temperature of the heat treatment is preferably 200 to 800°C, more preferably 300 to 700°C.

[0117] In the present invention, the heat treatment time is preferably 30 to 240 minutes, more preferably 70 to 200 minutes.

[0118] In the present invention, the metal foam substrate is preferably a pretreated metal foam substrate.

[0119] The present invention provides an anion exchange membrane water electrolyzer (AEMWE), the anion exchange membrane water electrolyzer comprising a cathode electrode;

[0120] The material of the cathode electrode includes an AEMWE cathode electrode material described in any one of the above technical solutions or an AEMWE cathode electrode material prepared by the preparation method described in any one of the above technical solutions.

[0121] The present invention provides an AEMWE cathode electrode material as described in any one of the above technical solutions or an AEMWE cathode electrode material prepared by the preparation method as described in any one of the above technical solutions, and its application in the field of hydrogen production by anion exchange membrane water electrolysis and / or hydrogen production by alkaline water electrolysis.

[0122] The AEMWE cathode electrode material provided by the present invention includes: a metal foam substrate, a transition metal hydroxide formed on the surface of the metal foam substrate, and a modified metal nanosheet array deposited on the surface of the metal hydroxide. Among them, the intermediate layer of metal hydroxide can promote proton-coupled electron transfer, induce metastable lattice distortion, and promote the formation of lattice dislocations / twins / distorted grain boundaries. At the same time, through the electric field or the multi-field coupling of electric field and magnetic field, the controllable growth of nanosheets is achieved, the hydrogen evolution performance is effectively improved, and the charge transfer resistance is greatly reduced, and the hydrogen evolution performance and long-term (>1000h) stability of the catalytic material under high current density and industrial conditions are achieved. The present invention provides an AEMWE solution that surpasses the commercial precious metal Pt / C||IrO2, and only 1.8V is required to achieve 1000mAcm -2 AEMWE electrolyzes water to produce hydrogen at a high current density and operates stably for more than 1000 hours.

[0123] The present invention is to complete and refine the overall technical solution, better ensure the specific structure and morphology of the AEMWE cathode electrode material, and further improve the performance of the AEMWE cathode electrode material in anion exchange membrane water electrolysis hydrogen production. The AEMWE cathode electrode material and its large-scale preparation method under high current density may specifically include the following contents:

[0124] An AEMWE cathode electrode material under high current density, comprising: a metal foam substrate, a transition metal hydroxide formed on the surface of the metal foam substrate, and a modified metal nanosheet array deposited on the surface of the metal hydroxide;

[0125] The transition metal hydroxide includes Ni(OH)2, Fe(OH)3, Mg(OH)2, Co(OH)3, Ce(OH)4, Mo(OH)3, etc.;

[0126] The modified metal nanosheet array includes a phosphorus-modified nanosheet array, a sulfur-modified nanosheet array and a selenium-modified nanosheet array; the metal element includes one, two or more of Co, Fe, Ni, Ce, Mn and Mo.

[0127] The present invention also provides a method for preparing an AEMWE cathode electrode material under high current density, comprising the following steps:

[0128] Step 1: pre-treating the metal foam substrate, washing and drying;

[0129] Step 2: Take a salt of a certain molar mass and dissolve it in a certain volume of deionized water to form a salt solution A with a certain concentration;

[0130] Step 3: placing the metal foam substrate material treated in step 1 in the salt solution A of step 2, depositing in an electric field or electric and magnetic field multi-field coupling and a nitrogen-rich atmosphere, washing and drying;

[0131] Step 4: Take a salt of a certain molar mass and dissolve it in a certain volume of deionized water to form a salt solution B with a certain concentration;

[0132] Step 5: Using the sample treated in step 3 as a working electrode, placing it in the salt solution B in step 4, depositing it in an electric field or a multi-field coupling of an electric field and a magnetic field and a nitrogen-rich atmosphere, washing it and drying it to obtain a precursor;

[0133] Step 6: Place the precursor in a tubular furnace and use a modifier to perform high-temperature treatment at a certain temperature to obtain the target cathode hydrogen evolution electrode material.

[0134] Specifically, the electrode material needs to include a metal hydroxide layer, including cobalt hydroxide, iron hydroxide, nickel hydroxide, cerium hydroxide, molybdenum hydroxide, and the like.

[0135] Specifically, in step three or step five, preparation needs to be carried out under the action of electric field or electric field and magnetic field multi-field coupling. The magnetic field is added by adding permanent magnets in the vertical direction of the electrode. The magnetic field strength at the center of the magnetic field is adjusted by changing the distance between the two groups of magnets. The magnetic field strength is 0-3T.

[0136] Specifically, the metal foam substrate used includes foamed nickel, foamed iron, foamed cobalt, foamed cobalt-iron, foamed nickel-iron, nickel mesh, and the like.

[0137] Specifically, the salts described in step 4 include cobalt salts, iron salts, nickel salts, cerium salts, manganese salts, and molybdenum salts. Among them, cobalt salts include cobalt nitrate, cobalt sulfate, cobalt chloride, cobalt carbonate, cobalt acetate, cobalt naphthenate, cobalt stearate, cobalt neodecanoate, and cobalt boroacylate, etc.; iron salts include ferric chloride, ferric sulfate, ferric nitrate, ferric carbonate, ferric acetate, ammonium ferric sulfate, etc.; nickel salts include nickel chloride, nickel sulfate, nickel nitrate, nickel carbonate, nickel acetate, etc.; cerium salts include cerium chloride, cerium sulfate, cerium nitrate, cerium carbonate, cerium acetate, etc.; manganese salts include manganese chloride, manganese sulfate, manganese nitrate, manganese carbonate, manganese acetate, etc.; molybdenum salts include molybdenum chloride, molybdenum sulfate, molybdenum nitrate, molybdenum carbonate, molybdenum acetate, ammonium molybdate, etc.

[0138] Specifically, the modifier used in step six is ​​a sulfur source modifier, a selenium source modifier or a phosphorus source modifier; wherein the sulfur source modifier is preferably sulfur and / or a sulfur-containing compound, specifically one or more of sulfur powder, thioacetamide, sodium sulfide and thiourea; the selenium source modifier is preferably selenium and / or a selenium-containing compound, specifically selenium powder and / or selenium dioxide; the phosphorus source modifier is preferably phosphorus and / or a phosphorus-containing compound, specifically one or more of potassium hypophosphite, potassium dihydrogen phosphate, red phosphorus and sodium hypophosphite.

[0139] Specifically, the electrodeposition methods used in step 3 and step 5 include constant potential deposition, constant current deposition, cyclic voltammetry, linear voltage scanning, etc.

[0140] Specifically, the size of the prepared AEMWE cathode electrode material can be 1*1cm 2 , 2*2cm 2 , 5*5cm 2 , 10*10cm 2 , 15*15cm 2 ……50*50cm 2 .

[0141] Furthermore,

[0142] Specifically, the metal foam substrate is preferably foamed nickel or foamed nickel-iron.

[0143] Specifically, in the step 1, the pretreatment step includes placing the metal foam substrate in a dilute hydrochloric acid solution, anhydrous ethanol and deionized water in sequence for ultrasonic treatment, and vacuum drying at low temperature.

[0144] Specifically, in step 1, the concentration of the dilute hydrochloric acid solution used is 1-4 mol / L, preferably 1 mol / L; the ultrasonic treatment is performed in the dilute hydrochloric acid solution for 1-30 min, preferably 15 min; the ultrasonic treatment is performed in anhydrous ethanol and deionized water for 1-30 min, preferably 15 min.

[0145] Specifically, in the step 2, the metal salt solution is controlled to include one or two of cobalt salts, iron salts, nickel salts, cerium salts, manganese salts, and molybdenum salts, wherein the cobalt salt is preferably cobalt nitrate and cobalt chloride, the iron salt is preferably ferric chloride and ferric nitrate, the nickel salt is preferably nickel nitrate and nickel chloride, the cerium salt is preferably cerium nitrate and cerium chloride, the molybdenum salt is preferably ammonium molybdate and molybdenum nitrate, and the manganese salt is preferably manganese chloride and manganese nitrate.

[0146] Specifically, in the step 2, the concentration of the metal salt solution is controlled to be 0.01-3.0 mol / L, specifically 0.01 mol / L, 0.02 mol / L, 0.03 mol / L, 0.04 mol / L, 0.05 mol / L, 0.06 mol / L, 0.07 mol / L, 0.08 mol / L, 0.09 mol / L, 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3mol / L, 1.4mol / L, 1.5mol / L, 1.6mol / L, 1.7mol / L, 1.8mol / L, 1.9mol / L, 2.0mol / L, 2.1mol / L, 2.2mol / L, 2.3mol / L, 2.4mol / L, 2.5mol / L, 2.6mol / L, 2.7mol / L, 2.8mol / L, 2.9mol / L, 3.0mol / L, etc. The transition metal hydroxide nanolayer deposited at this concentration can construct a highly active dissociation layer, break the H-OH bond, and reduce the loss of active sites in the hydrogen evolution reaction, thereby accelerating the Volmer step.

[0147] Specifically, the drying in step 1, step 3 and step 5 refers to drying in a vacuum drying oven at 50-80° C. for 6-24 hours.

[0148] Specifically, in step three or step five, it is necessary to prepare under the action of electric field or electric field and magnetic field multi-field coupling. The magnetic field is added by adding a permanent magnet in the vertical direction of the electrode. The permanent magnet includes rare earth permanent magnet, samarium cobalt permanent magnet, aluminum nickel cobalt permanent magnet, copper nickel iron permanent magnet, iron cobalt molybdenum permanent magnet, iron cobalt vanadium permanent magnet, manganese bismuth permanent magnet, etc. The permanent magnet is preferably a square permanent magnet. The magnetic field strength at the center of the magnetic field is adjusted by changing the distance between the two groups of magnets. The distance adjustment range is 1-50cm, and the magnetic field strength is 0-3T.

[0149] Specifically, the electrodeposition method used in step 3 or step 5 includes constant potential deposition, constant current deposition, cyclic voltammetry, etc. Specifically, the potential range of constant potential deposition is 0.1-10V, the current range of constant current deposition is 0.1-2A, and the scanning range of deposition by cyclic voltammetry is -10-10V, the scanning rate is 5-100mV / s, and the number of scanning circles is 5-1000 circles;

[0150] Specifically, the deposition time in solution A in step three or solution B in step five is preferably 15-60 minutes.

[0151] Specifically, in step 3 and step 5, when placing the porous carrier / sample in solution A or solution B, it is required that the porous carrier / sample is completely immersed in solution A or solution B.

[0152] Specifically, the salt in step 4 includes cobalt salts, iron salts, nickel salts, cerium salts, manganese salts, and molybdenum salts. Among them, the cobalt salt is preferably cobalt nitrate, cobalt sulfate, and cobalt chloride; the iron salt is preferably ferric chloride, ferric sulfate, and ferric nitrate; the nickel salt is preferably nickel chloride, nickel sulfate, and nickel nitrate; the manganese salt is preferably manganese chloride, manganese sulfate, and manganese nitrate; the cerium salt is preferably cerium chloride and cerium nitrate; the molybdenum salt is preferably molybdenum nitrate, ammonium molybdate, and the like.

[0153] Specifically, in the step 4, the solution B is controlled to contain one, two or more of cobalt salt, iron salt, nickel salt, cerium salt, manganese salt and molybdenum salt, and the total ion concentration of the metal source in the metal solution is preferably 0.1-3 mol / L, specifically 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2mol / L, 1.3mol / L, 1.4mol / L, 1.5mol / L, 1.6mol / L, 1.7mol / L, 1.8mol / L, 1.9mol / L, 2.0mol / L, 2 .1mol / L, 2.2mol / L, 2.3mol / L, 2.4mol / L, 2.5mol / L, 2.6mol / L, 2.7mol / L, 2.8mol / L, 2.9mol / L or 3.0mol / L.

[0154] Specifically, in the step 4, the metal source is most preferably a Co source and a Fe source, and the molar ratio of the Co source calculated as Co atoms to the Fe source calculated as Fe atoms is preferably 4:(0.01-1), specifically 4:0.01, 4:0.05, 4:0.1, 4:0.25, 4:0.5, 4:0.75 or 4:1.

[0155] Specifically, in step three or step five, Hg / Hg2Cl2 or Ag / AgCl or Hg / HgO is used as a reference electrode, and platinum sheet / platinum wire / carbon rod is used as a counter electrode, and electrodeposition is performed in a three-electrode system.

[0156] Specifically, in step three or step five, the deposition temperature is preferably 20-50°C.

[0157] Specifically, in step six, the precursor is placed in a tube furnace for modification, and the carrier gas atmosphere is preferably nitrogen or argon.

[0158] Specifically, in step six, the precursor is placed in a tube furnace for modification, and the heating rate is preferably 0.5-10° C. / min.

[0159] Specifically, in step six, the precursor is placed in a tube furnace for modification, the final reaction temperature is preferably 200-800° C., and the holding time is preferably 30-240 min.

[0160] The AEMWE cathode electrode material provided by the present invention is a monolithic integrated electrode. The electrode can be applied to hydrogen production by anion exchange membrane water electrolysis and alkaline water electrolysis under high current density and industrial conditions.

[0161] The above content of the present invention provides an AEMWE cathode electrode material under high current density and its macro-scale preparation method and application. The present invention provides an AEMWE cathode electrode material with a specific morphology and composition, and is a cathode electrode material that can be used for AEMWE under high current density, with the characteristics of large current, high activity and easy scale-up production. The present invention also provides a corresponding AEMWE cathode electrode material preparation method, through the electric field or electric field and magnetic field multi-field coupling, to achieve controllable growth of nanosheets, and use a modifier for high-temperature modification, thereby obtaining a modified metal nanosheet material, the preparation method is simple and easy, suitable for industrialization and commercial promotion.

[0162] The AEMWE cathode electrode material provided by the present invention comprises an intermediate layer - a transition metal hydroxide. The highly active dissociation layer constructed by the intermediate layer is beneficial to breaking the H-OH bond, while reducing the loss of active sites during the hydrogen evolution reaction and accelerating the Volmer step. At the same time, the macroscopic magnetohydrodynamic effect and microscopic magnetohydrodynamic effect generated by the Lorentz force increase the liquid phase mass transfer rate, and the performance of the AEMWE cathode electrode material is improved by affecting various steps such as liquid phase mass transfer and electrode polarization during the deposition process.

[0163] The test results show that the AEMWE cathode electrode material provided by the present invention, in the membrane electrode (industrial pilot) test, with the homemade catalyst of this experiment as the anode (CN115404505A) and the Xiamen University Jiame as the anion exchange membrane, when the current is 4A, the battery voltage is 1.80V (commercial Pt / C||IrO2 is 1.87V), and can run stably for 1000h (test conditions: 1M KOH, 80℃, membrane electrode assembly size is 2*2cm 2 ).

[0164] To further illustrate the present invention, an AEMWE cathode electrode material provided by the present invention, a preparation method thereof, and an application thereof are described in detail below in combination with embodiments. However, it should be understood that these embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are given only to further illustrate the features and advantages of the present invention, rather than to limit the claims of the present invention. The protection scope of the present invention is not limited to the embodiments described below.

[0165] Example 1

[0166] The method for preparing the AEMWE cathode electrode material CoFeCeP-Ni(OH)2 / NF at a high current density described in this embodiment comprises the following steps:

[0167] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0168] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0169] (3) The nickel foam treated in step (1) is placed in the salt solution A of step (2), and is electrodeposited in a water bath at 40° C. in an external magnetic field and a nitrogen-rich atmosphere, and then washed and dried to obtain Ni(OH)2 / NF, the SEM morphology of which is shown in FIG. Figure 1 shown.

[0170] (4) Weigh 4 mmol of cobalt nitrate hexahydrate, 1 mmol of iron nitrate hexahydrate, and 0.1 mmol of cerium nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0171] (5) The obtained solution B is placed in a water bath at 40°C. After the solution temperature stabilizes, the sample treated in step (3) is used as the working electrode. A three-electrode system is used to perform electrodeposition in an external magnetic field and a nitrogen-rich atmosphere. The sample is taken out, rinsed with deionized water three times, and placed in a vacuum oven at 60°C for 12 hours to obtain a precursor.

[0172] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium hypophosphite was used as a modifier. Nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0173] See also Figure 1 , Figure 1 This is the SEM morphology of Ni(OH)2 / NF prepared in Example 1 of the present invention.

[0174] See also Figure 2 , Figure 2 This is the SEM morphology of CoFeCeP-Ni(OH)2 / NF prepared in Example 1 of the present invention.

[0175] See also Figure 3 , Figure 3 This is the XRD spectrum of CoFeCeP-Ni(OH)2 / NF prepared in Example 1 of the present invention.

[0176] As attached Figure 1 As shown, the nanosheets are randomly attached to the nickel foam and are densely arranged, which can provide a lot of contact area and active sites.

[0177] As attached Figure 2As shown, the nanosheets grow randomly and vertically on the surface of the metal foam substrate, and the diameter of the vertically uniformly distributed nanosheets is roughly estimated to be about 3-6 microns.

[0178] As attached Figure 3 As shown in the figure, it can be seen that there are Ni2P, CeO2 and Fe in the material 83 P 17 Among them, Ni comes from the metal salt solution obtained by the first deposition, and then forms Ni2P after phosphating. Co, Fe, and Ce are transition metals deposited in the second deposition, and P comes from the high-temperature reaction of the modifier.

[0179] See also Figure 4 , Figure 4 The figure is the relationship between LSV, electrochemical impedance spectroscopy (EIS) and current density and time of the CoFeCeP-Ni(OH)2 / NF material prepared in Example 1 of the present invention. Figure 4 (1) is the LSV curve of hydrogen evolution in water electrolysis of the material in alkaline solution, Figure 4 (2) is the electrochemical impedance spectroscopy (EIS) of the material in alkaline solution, Figure 4 (3) Test the stability of the material in hydrogen evolution during water electrolysis in alkaline solution.

[0180] from Figure 4 (1) It can be seen that the hydrogen evolution performance of the material is 1000mA / cm 2 When 222mV;

[0181] from Figure 4 (2) It can be seen that the charge transfer resistance of the material is 3.24Ω;

[0182] from Figure 4 (3) shows that the material is 1000mA / cm 2 The current density can be maintained for 100 h without significant change, so this material has good hydrogen evolution stability.

[0183] Example 2

[0184] The method for preparing CoFeS-Ni(OH)2 / NF, an AEMWE cathode electrode material at a high current density, described in this embodiment, comprises the following steps:

[0185] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0186] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0187] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), electro-depositing in a water bath at 40° C., in an external magnetic field and a nitrogen-rich atmosphere, washing and drying to obtain Ni(OH)2 / NF;

[0188] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of ferric nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0189] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in an external magnetic field and a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0190] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium sulfide was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0191] Example 3

[0192] The method for preparing CoFeSe-Ni(OH)2 / NF, an AEMWE cathode electrode material at a high current density, described in this embodiment, comprises the following steps:

[0193] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0194] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0195] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), electro-depositing in a water bath at 40° C., in an external magnetic field and a nitrogen-rich atmosphere, washing and drying to obtain Ni(OH)2 / NF;

[0196] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of ferric nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0197] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in an external magnetic field and a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0198] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Selenium oxide was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0199] Example 4

[0200] The method for preparing CoFeP-Ni(OH)2 / NF, an AEMWE cathode electrode material at a high current density, described in this embodiment, comprises the following steps:

[0201] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0202] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0203] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), electro-depositing in a water bath at 40° C., in an external magnetic field and a nitrogen-rich atmosphere, washing and drying to obtain Ni(OH)2 / NF;

[0204] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of ferric nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0205] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in an external magnetic field and a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0206] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium hypophosphite was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0207] Example 5

[0208] AEMWE cathode electrode material CoFe at high current density described in this embodiment min The preparation method of P-Ni(OH)2 / NF comprises the following steps:

[0209] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0210] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0211] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), performing electrodeposition in a nitrogen-rich atmosphere at 40° C. in a water bath, washing and drying to obtain Ni(OH)2 / NF;

[0212] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 0.1 mmol of ferric nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0213] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0214] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium hypophosphite was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0215] Example 6

[0216] The method for preparing the AEMWE cathode electrode material CoMoS-Ni(OH)2 / NF at a high current density described in this embodiment comprises the following steps:

[0217] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0218] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0219] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), performing electrodeposition in a nitrogen-rich atmosphere at 40° C. in a water bath, washing and drying to obtain Ni(OH)2 / NF;

[0220] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of ammonium molybdate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0221] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0222] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium sulfide was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0223] Example 7

[0224] The method for preparing the AEMWE cathode electrode material CoNiS-Co(OH)2 / NF at a high current density described in this embodiment comprises the following steps:

[0225] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0226] (2) Weigh 10 mmol of cobalt nitrate hexahydrate and prepare 40 mL of solution A;

[0227] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), performing electrodeposition in a nitrogen-rich atmosphere at 40° C. in a water bath, washing and drying to obtain Co(OH)2 / NF;

[0228] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of nickel nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0229] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0230] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium sulfide was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0231] Example 8

[0232] The method for preparing the AEMWE cathode electrode material CoCeP-Ni(OH)2 / NF at a high current density described in this embodiment comprises the following steps:

[0233] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0234] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0235] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), performing electrodeposition in a nitrogen-rich atmosphere at 40° C. in a water bath, washing and drying to obtain Ni(OH)2 / NF;

[0236] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of cerium nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0237] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0238] (6) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium hypophosphite was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0239] Comparative Example 1

[0240] The material of this comparative example is a material without a metal hydroxide layer (referred to as CoFeP / NF), and the specific preparation process is as follows:

[0241] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0242] (2) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of ferric nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0243] (3) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using nickel foam as the working electrode, using a three-electrode system, and performing electrodeposition in a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0244] (4) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium hypophosphite was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0245] Comparative Example 2

[0246] The material of this comparative example is a material without adding a modifier (referred to as CoFe-Ni(OH)2 / NF), and the specific preparation process is as follows:

[0247] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0248] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0249] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), performing electrodeposition in a nitrogen-rich atmosphere at 40° C. in a water bath, washing and drying to obtain Ni(OH)2 / NF;

[0250] (4) Weigh 4 mmol of cobalt nitrate hexahydrate and 1 mmol of ferric nitrate hexahydrate, add 50 mL of deionized water and stir until clear to obtain solution B;

[0251] (5) placing the obtained solution B in a water bath at 40° C., and after the solution temperature stabilizes, using the sample treated in step (3) as the working electrode, using a three-electrode system, and performing electrodeposition in a nitrogen-rich atmosphere, taking out the sample, rinsing it with deionized water three times, and placing it in a vacuum oven at 60° C. and drying it for 12 h to obtain a precursor;

[0252] Comparative Example 3

[0253] The material of this comparative example is a material that only forms metal hydroxide (referred to as Ni(OH)2 / NF), and the specific preparation process is as follows:

[0254] (1) Commercial nickel foam was cut into a size of 20 mm*30 mm, and ultrasonically treated in 1 M dilute hydrochloric acid for 15 min, anhydrous ethanol and deionized water for 15 min each, and then vacuum dried at 60° C. for 12 h for later use;

[0255] (2) Weigh 10 mmol of nickel nitrate hexahydrate and prepare 40 mL of solution A;

[0256] (3) placing the nickel foam treated in step (1) in the salt solution A of step (2), performing electrodeposition in a nitrogen-rich atmosphere at 40° C. in a water bath, washing and drying to obtain Ni(OH)2 / NF;

[0257] (4) The precursor was placed in a quartz boat and placed in a tube furnace. Sodium hypophosphite was used as a modifier and nitrogen was used as a carrier gas. The temperature was raised to 350° C. at a rate of 2° C. / min and maintained for 3 h to obtain the target catalyst.

[0258] The AEMWE cathode electrode materials in the examples and comparative examples were tested for performance as follows:

[0259] The electrochemical test was carried out on an electrochemical workstation, using the cathode electrode material prepared as above as the cathode, the carbon rod as the counter electrode, and Hg / HgO as the reference electrode. The linear scanning curve, electrochemical impedance and stability of the cathode electrode material were measured in 1 mol / L KOH solution.

[0260] The test results are shown in Table 1:

[0261] Table 1 Performance data of electrocatalytic hydrogen evolution of materials in different embodiments and comparative examples

[0262]

[0263]

[0264] In addition, the present invention also performs performance tests on CoFeCeP-Ni(OH)2 / NF cathode electrode materials, commercial nickel foam, and commercial PtC / IrO2 according to the following method:

[0265] Anion exchange membrane water electrolysis test was carried out using a 2cm*2cm anion exchange membrane electrolyzer. CoFeCeP-Ni(OH)2 / NF was used as the cathode electrode material, and the homemade catalyst in this laboratory was used as the AEMWE anode electrode material. In the comparative example, two pieces of pure nickel foam were used, and commercial PtC and IrO2 were used as the cathode and anode respectively. Xiamen University Jiamo was used as the anion exchange membrane to form a membrane electrode. The membrane electrode test was carried out in 1M KOH solution. Figure 5 The test results show that at a current of 4A, the battery voltage is 1.80V and the stability is 1000h without attenuation, which is much lower than commercial PtC / IrO2 (1.87V).

[0266] See also Figure 5 , Figure 5This is the test curve of AEMWE assembled with the cathode material prepared in Example 1 of the present invention.

[0267] Figure 5 In the test, Example 1 is the cathode material, which is a 2*2cm 2 In the industrial-grade water electrolysis test of AEMWE, MEA can reach a cell voltage of 1.80V at a current of 4A (commercial Pt / C||IrO2 is 1.87V) and operate stably for 1000h.

[0268] In summary, it can be seen that the AEMWE cathode electrode material provided by the present invention has excellent hydrogen evolution performance in alkaline solution.

[0269] The above is a detailed introduction to the AEMWE cathode electrode material and its macro-preparation method and application under a high current density provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core ideas of the present invention, including the best mode, and also enables any technician in the field to practice the present invention, including the manufacture and use of any device or system, and the implementation of any combined method. It should be pointed out that for ordinary technicians in the technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements that are not different from the textual expression of the claims, or if they include equivalent structural elements that are not substantially different from the textual expression of the claims, then these other embodiments should also be included in the scope of the claims.

Claims

1. An AEMWE cathode electrode material, characterized in that: include: A metal foam substrate, a transition metal hydroxide layer composited on the metal foam substrate, and a modified transition metal-based nanosheet array composited on the transition metal hydroxide layer; The transition metal in the transition metal hydroxide layer is Co or Ni; The transition metal in the modified transition metal-based nanosheet array is two or more of Co, Fe, Ni, Ce and Mo; The modification is phosphorus modification, sulfur modification or selenium modification; The preparation method of the AEMWE cathode electrode material comprises the following steps: 1) placing a metal foam substrate in a soluble transition metal salt solution A as a working electrode, and performing a first deposition under the multi-field coupling of electric and magnetic fields and a nitrogen-rich atmosphere to obtain a metal foam substrate composited with a transition metal hydroxide layer; The metal foam substrate comprises foamed nickel, foamed iron, foamed cobalt, foamed cobalt-iron or foamed nickel-iron; 2) placing a soluble transition metal salt solution B in an electroplating tank, using the metal foam substrate composited with a transition metal hydroxide layer obtained in the above step as a working electrode, and performing a second deposition under the multi-field coupling of electric and magnetic fields and a nitrogen-rich atmosphere to obtain a precursor; The transition metal in the soluble transition metal salt solution A is Co or Ni; The transition metal in the soluble transition metal salt solution B is two or more of Co, Fe, Ni, Ce and Mo; The soluble transition metal salt solution A and the soluble transition metal salt solution B are aqueous solutions, and the concentration of the transition metal is independently selected from 0.01 to 3.0 mol / L; 3) Under a protective atmosphere, the precursor and the modifier obtained in the above step are heat treated to obtain the AEMWE cathode electrode material; The modifier is a sulfur source modifier, a selenium source modifier or a phosphorus source modifier; The sulfur source modifier is one or more of sulfur powder, thioacetamide, sodium sulfide and thiourea; The selenium source modifier is selenium powder and / or selenium dioxide; The phosphorus source modifier is one or more of potassium hypophosphite, potassium dihydrogen phosphate, red phosphorus and sodium hypophosphite; The mass ratio of the transition metal-based nanosheets in the transition metal-based nanosheet array in the precursor to the mass ratio of the modifier is (1-2): (1-10); The temperature of the heat treatment is 200-800°C; The heat treatment time is 30 to 240 minutes.

2. The AEMWE cathode electrode material according to claim 1, characterized in that: The transition metal hydroxide layer is specifically a transition metal hydroxide nanosheet array layer formed by longitudinally staggered growth; The transition metal hydroxide layer has a clustered surface structure formed by staggered growth of nanosheets; The thickness of the transition metal hydroxide nanosheet is 1 to 50 nm; The transition metal hydroxide nanosheet has a sheet diameter of 10 nm to 10 μm; A porous structure is formed between the nanosheets of the transition metal hydroxide layer; The thickness of the transition metal hydroxide layer is 10 nm to 20 μm; The mass ratio of the metal foam substrate to the transition metal hydroxide layer is (1-10):

1.

3. The AEMWE cathode electrode material according to claim 1, characterized in that: The modified transition metal-based nanosheet arrays are staggered and composited on the transition metal hydroxide nanosheets in the transition metal hydroxide layer; The modified transition metal-based nanosheet array has a cluster structure formed by staggered growth; The thickness of the modified transition metal-based nanosheet is 1 to 50 nm; The modified transition metal-based nanosheet has a sheet diameter of 10 nm to 10 μm.

4. The AEMWE cathode electrode material according to claim 1, characterized in that: A porous structure is formed between the nanosheets of the modified transition metal-based nanosheet array; The transition metal elements in the modified transition metal-based nanosheet array include transition metal elements in the transition metal hydroxide layer and transition metal elements added during the preparation of the modified transition metal-based nanosheet; The thickness of the modified transition metal-based nanosheet array layer is 10 nm to 20 μm; The modified transition metal-based nanosheets include one or more of transition metals, transition metal alloys and transition metal oxides, as well as modified transition metal compounds.

5. The AEMWE cathode electrode material according to claim 1, characterized in that: The mass ratio of the metal foam substrate to the modified transition metal-based nanosheet array is (3-20): 1; The surface of the modified transition metal-based nanosheet is also compounded with modified transition metal-based nanoparticles; The particle size of the modified transition metal-based nanoparticles is 1 to 50 nm.

6. The AEMWE cathode electrode material according to claim 1, characterized in that: The transition metal hydroxide layer and the modified transition metal-based nanosheet array have a topological structure of one or more of lattice dislocation, twinning and distorted grain boundary structure; The AEMWE cathode electrode material includes cathode electrode materials of AEMWE for use under high current density conditions.

7. The AEMWE cathode electrode material according to claim 1, characterized in that: The time of the first deposition and the second deposition are each independently selected from 15 to 60 minutes; The temperatures of the first deposition and the second deposition are independently selected from 20 to 50° C.; The first deposition and the second deposition are independently carried out by one or more of constant potential deposition, constant current deposition, cyclic voltammetry and linear voltage scanning.

8. The AEMWE cathode electrode material according to claim 1, characterized in that: The first deposition and the second deposition are each specifically performed by using Hg / Hg2Cl2 or Ag / AgCl or Hg / HgO as a reference electrode and a platinum sheet / platinum wire / carbon rod as a counter electrode for deposition; The magnetic field is added in a specific manner by adding magnets in a direction perpendicular to the electrode, and adjusting the magnetic field strength at the center of the magnetic field by changing the distance between the two groups of magnets; The magnetic field strength is 0.01~3T.

9. The AEMWE cathode electrode material according to claim 1, characterized in that: The metal foam substrate is specifically a pretreated metal foam substrate.

10. Application of an AEMWE cathode electrode material according to any one of claims 1 to 9 in the field of hydrogen production by anion exchange membrane water electrolysis and / or hydrogen production by alkaline water electrolysis.

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