Preparation method of thermal sprayed nickel wire mesh electrode and nickel wire mesh electrode

Abstract

The present invention relates to a method for preparing a thermally sprayed nickel wire mesh electrode, comprising the following steps: S1, preparing a nickel wire mesh; S2, sandblasting; S3, first catalyst spraying: spraying a first catalyst alloy powder on the surface of the nickel wire mesh using an array plasma thermal spraying method so that a large-particle catalyst layer is deposited on the surface of the nickel wire mesh, wherein the first catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a noble metal catalyst, or a noble metal oxide catalyst; S4, first activation; S5, second catalyst spraying: spraying a second catalyst alloy powder on the surface of the nickel wire mesh using an array plasma thermal spraying method; S6, second activation; and S7, cleaning and storage. The preparation method of the present invention forms a dendritic structure in the nickel wire mesh electrode catalyst particles, which can greatly increase the specific surface area of ​​the catalyst, thereby significantly improving the catalyst's efficiency in producing hydrogen through water electrolysis.

Description

Technical Field

[0001] The invention relates to the technical field of nickel wire mesh electrodes for hydrogen production, in particular to a preparation method of a thermal sprayed nickel wire mesh electrode and the nickel wire mesh electrode. Background Art

[0002] As global energy is currently developing towards low-carbonization, hydrogen energy is considered to be an important carrier for building a "multi-energy complementary" energy supply system and a key energy source for achieving a carbon neutrality strategy. At present, alkaline water electrolysis to produce hydrogen is a hydrogen production technology with a relatively high market maturity, and a large number of alkaline catalyst systems have been developed. Traditional alkaline water electrolysis to produce hydrogen nickel mesh electrodes generally use nickel mesh sprayed with porous nickel metal or alloy, which has a low specific surface area, resulting in low efficiency. In addition, the uniformity of the existing nickel mesh electrode spraying catalyst process still needs to be further improved. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a preparation method of a thermally sprayed nickel wire mesh electrode and the nickel wire mesh electrode.

[0004] The technical solution adopted by the present invention to solve the above technical problems is: on the one hand, a method for preparing a thermally sprayed nickel wire mesh electrode comprises the following steps:

[0005] S1. Prepare nickel wire mesh: cut the nickel wire mesh into the required size;

[0006] S2. Sandblasting: Use a sandblasting machine to perform sandblasting surface treatment on the surface of the nickel wire mesh;

[0007] S3. First catalyst spraying: preparing a first catalyst into an alloy powder, and spraying the first catalyst alloy powder on the surface of the nickel wire mesh treated in step S2 using an array plasma thermal spraying method, so that a large particle catalyst layer is deposited on the surface of the nickel wire mesh, and the first catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a noble metal catalyst, or a noble metal oxide catalyst;

[0008] S4, first activation: using 10% to 70% caustic soda solution to activate the nickel wire mesh after the treatment in step S3 for 1 to 10 hours;

[0009] S5. Second catalyst spraying: The second catalyst is prepared into an alloy powder, and the second catalyst alloy powder is sprayed on the surface of the nickel wire mesh treated in step S4 using an array plasma thermal spraying method, so that a small particle catalyst layer with a dendritic structure is deposited on the surface of the nickel wire mesh. The second catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a noble metal catalyst, or a noble metal oxide catalyst; the alloy composition of the second catalyst is the same as or different from that of the first catalyst;

[0010] S6, second activation: using 10% to 70% caustic soda solution to activate the nickel wire mesh after the treatment in step S5 for 1 to 10 hours;

[0011] S7. Cleaning and storage: Clean the nickel wire mesh treated in step S6 with clean water, dry it, and store it.

[0012] Preferably, the array plasma thermal spraying in steps S3 and S5 is: arranging a plurality of plasma nozzles into a rectangular array.

[0013] Preferably, in step S3, the first catalyst alloy powder is sprayed on the surface of the nickel mesh so that a large particle catalyst layer with a particle size of 1 to 20 μm is deposited on the surface of the nickel mesh;

[0014] In step S5, the catalyst alloy powder is sprayed on the surface of the nickel wire mesh for the second time so that a small particle catalyst layer with a particle size of 1 to 900 nm is deposited on the surface of the nickel wire mesh.

[0015] Preferably, the transition metal alloy catalyst is NiAl or NiFeAl or NiMoAl or NiFeCo or NiFeCoAl, the transition metal oxide catalyst is NiFe2O4Al or Ni(CoFe)2O4, the noble metal catalyst is PtAl or IrAl or RuAl, and the noble metal oxide catalyst is RuO2Al or IrO2Al.

[0016] Preferably, the first catalyst or the second catalyst includes the following components in percentage by weight:

[0017] Ni: 40-80%;

[0018] Al: 10-30%;

[0019] One or more of Fe, Co, Mo, W:

[0020] Fe: 5-40%;

[0021] Co: 5-40%;

[0022] Mo: 5-40%;

[0023] W: 5-40%.

[0024] Preferably, the first catalyst is NiFeCo; wherein the alloy ratio is Ni 80%, Fe 10%, Co 10%;

[0025] The second catalyst is NiFeCo, wherein the alloy ratio is Ni 80%, Fe 10%, and Co 10%.

[0026] On the other hand, a nickel wire mesh electrode for producing hydrogen by alkaline water electrolysis is prepared by the above-mentioned method for preparing a thermally sprayed nickel wire mesh electrode.

[0027] The beneficial effects of the present invention are as follows: the nickel mesh electrode of the present invention adopts an array-type thermal spraying process, which can realize efficient spraying of nickel mesh electrode catalyst particles, and is also conducive to the preparation of highly uniform catalyst particles. The nickel mesh electrode of the present invention is prepared by a secondary spraying plus secondary activation process; after the first catalyst spraying and the first activation process, porous large-sized catalyst deposited particles are formed, and a layer of catalyst with smaller particle size is deposited on the surface of the porous large-sized catalyst deposited particles through the second catalyst spraying and the second activation process, thereby forming a catalytic layer nickel mesh electrode with a high specific surface area. Through the preparation method of the present invention, the nickel mesh electrode catalyst particles form a tree-like structure, which can greatly increase the specific surface area of ​​the catalyst, thereby significantly improving the efficiency of the catalyst in producing hydrogen by electrolysis of water. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The LSV curves of nickel wire mesh electrodes are produced by conventional Ni electroplating, one-time spraying and activation of NiFeCo, and the second-time spraying and activation of NiFeCo according to the present invention. DETAILED DESCRIPTION

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0030] The technical solution adopted by the present invention to solve the above technical problems is: on the one hand, a method for preparing a thermally sprayed nickel wire mesh electrode comprises the following steps:

[0031] S1. Prepare nickel wire mesh: cut the nickel wire mesh into the required size; specifically, in an optional embodiment, cut the nickel wire mesh with a mesh size of 30 to 100 and a wire diameter of 100 to 400 μm into the required size.

[0032] S2. Sandblasting: The surface of the nickel wire mesh is sandblasted using a sandblasting machine; specifically, in an optional embodiment, the sandblasting particles are 10-20 μm corundum, the sandblasting pressure is 0.3-0.6 MPa, the sandblasting distance is 120-180 mm, and the sandblasting angle is 60-75°.

[0033] S3. First catalyst spraying: The first catalyst is prepared into an alloy powder, and the first catalyst alloy powder is sprayed on the surface of the nickel wire mesh treated in step S2 using an array plasma thermal spraying method, so that a large-particle catalyst layer with a particle size of 1 to 20 μm is deposited on the surface of the nickel wire mesh. The first catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a precious metal catalyst, or a precious metal oxide catalyst; array plasma thermal spraying is: multiple plasma nozzles are arranged in a rectangular array.

[0034] Specifically, an optional implementation is as follows: Figure 1 As shown, the first catalyst uses NiFeCo, wherein the alloy ratio is Ni 80%, Fe 10%, and Co 10%.

[0035] S4, first activation: using 10-70% caustic soda solution to activate the nickel wire mesh after step S3 for 1-10 hours;

[0036] S5. Second catalyst spraying: The second catalyst is prepared into an alloy powder, and the second catalyst alloy powder is sprayed on the surface of the nickel wire mesh treated in step S4 using an array plasma thermal spraying method, so that a small particle catalyst layer with a particle size of 1 to 900 nm is deposited on the surface of the nickel wire mesh. The second catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a noble metal catalyst, or a noble metal oxide catalyst. The array plasma thermal spraying method comprises: arranging multiple plasma nozzles in a rectangular array;

[0037] Specifically, an optional implementation is as follows: Figure 1 As shown, the second catalyst uses NiFeCo, wherein the alloy ratio is Ni 80%, Fe 10%, and Co 10%.

[0038] S6, second activation: using 10% to 70% caustic soda solution to activate the nickel wire mesh after the treatment in step S5 for 1 to 10 hours;

[0039] S7. Cleaning and storage: Clean the nickel wire mesh treated in step S6 with clean water, dry it, and store it.

[0040] Specifically, in an optional embodiment, the first catalyst or the second catalyst may be a catalyst in the following form, including the following components in percentage by weight:

[0041] Ni: 40-80%;

[0042] Al: 10-30%;

[0043] One or more of Fe, Co, Mo, W:

[0044] Fe: 5-40%;

[0045] Co: 5-40%;

[0046] Mo: 5-40%;

[0047] W: 5-40%.

[0048] Preparation of catalyst alloy powder: According to the alloy composition formula, prepare transition metal alloy catalyst, or transition metal oxide catalyst, or noble metal catalyst, or noble metal oxide catalyst powder.

[0049] Specifically, an optional embodiment is that the transition metal alloy catalyst is NiAl or NiFeAl or NiMoAl or NiFeCo or NiFeCoAl, the transition metal oxide catalyst is NiFe2O4Al or Ni(CoFe)2O4, the precious metal catalyst is PtAl or IrAl or RuAl, and the precious metal oxide catalyst is RuO2Al or IrO2Al.

[0050] Specifically, in one optional embodiment, the first spraying process for spraying the catalyst alloy powder onto the nickel mesh surface employs an argon flow rate of 40 to 80 L / min, a hydrogen flow rate of 1 to 10 L / min, a spraying distance of 80 to 150 mm, and a powder feed rate of 1 to 18 r / min. The process parameters for the second spraying process for spraying the catalyst alloy powder onto the nickel mesh surface are adaptively adjusted based on the parameters of the first spraying process.

[0051] On the other hand, a nickel wire mesh electrode for producing hydrogen by alkaline water electrolysis is prepared by the above-mentioned method for preparing a thermally sprayed nickel wire mesh electrode.

[0052] The nickel mesh electrode in the present invention adopts an array-type thermal spraying process, which can achieve efficient spraying of nickel mesh electrode catalyst particles, and is also conducive to the preparation of highly uniform catalyst particles. The nickel mesh electrode in the present invention is prepared by a secondary spraying plus secondary activation process; after the first catalyst spraying and the first activation process, porous large-sized catalyst deposition particles are formed, and a layer of catalyst with smaller particle size is deposited on the surface of the porous large-sized catalyst deposition particles through a second catalyst spraying and a second activation process, thereby forming a catalytic layer nickel mesh electrode with a high specific surface area. Through the preparation method of the present invention, the nickel mesh electrode catalyst particles form a tree-like structure, which can greatly increase the specific surface area of ​​the catalyst, thereby significantly improving the efficiency of the catalyst in producing hydrogen by electrolysis of water.

[0053] like Figure 1The LSV curves of conventional electroplated Ni, one-time spray activated NiFeCo, and two-time spray activated NiFeCo are shown. The LSV curve mainly characterizes the polarization of the catalyst. Figure 1 The order of polarization from highest to lowest is: conventional Ni electroplating > single-spray activated NiFeCo > secondary spray activated NiFeCo. For both cathode and anode catalysts, the lower the polarization, the lower the overpotential at the same current density, thus reducing energy loss and improving water electrolysis performance.

[0054] The above description only describes specific embodiments of the present invention. Various examples do not limit the essential content of the present invention. After reading the description, ordinary technicians in the relevant technical field can make modifications or variations to the specific embodiments described above without departing from the essence and scope of the invention.

Claims

1. A method for preparing a thermally sprayed nickel wire mesh electrode, characterized in that: The steps include: S1. Prepare nickel wire mesh: cut the nickel wire mesh into the required size; S2. Sandblasting: Use a sandblasting machine to perform sandblasting surface treatment on the surface of the nickel wire mesh; S3. First catalyst spraying: preparing a first catalyst into an alloy powder, and spraying the first catalyst alloy powder on the surface of the nickel wire mesh treated in step S2 using an array plasma thermal spraying method, so that a large particle catalyst layer is deposited on the surface of the nickel wire mesh, wherein the first catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a noble metal catalyst, or a noble metal oxide catalyst; The first catalyst alloy powder is sprayed on the surface of the nickel wire mesh so that a large particle catalyst layer with a particle size of 1 to 20 μm is deposited on the surface of the nickel wire mesh; S4, first activation: using 10-70% caustic soda solution to activate the nickel wire mesh after the treatment in step S3 for 1-10 hours; S5. Second catalyst spraying: The second catalyst is prepared into an alloy powder, and the second catalyst alloy powder is sprayed on the surface of the nickel wire mesh treated in step S4 using an array plasma thermal spraying method, so that a small particle catalyst layer is deposited on the surface of the nickel wire mesh. The second catalyst is a transition metal alloy catalyst, a transition metal oxide catalyst, a noble metal catalyst, or a noble metal oxide catalyst; the alloy composition of the second catalyst is the same as or different from that of the first catalyst; The catalyst alloy powder is sprayed on the surface of the nickel mesh for the second time so that a small particle catalyst layer with a particle size of 1 to 900 nm is deposited on the surface of the nickel mesh; S6, second activation: using 10% to 70% caustic soda solution to activate the nickel wire mesh after the treatment in step S5 for 1 to 10 hours; S7. Cleaning and storage: Clean the nickel wire mesh treated in step S6 with clean water, dry it, and store it.

2. The method for preparing a thermally sprayed nickel wire mesh electrode according to claim 1, wherein: The array plasma thermal spraying in steps S3 and S5 is as follows: a plurality of plasma nozzles are arranged in a rectangular array.

3. The method for preparing a thermally sprayed nickel wire mesh electrode according to claim 1, wherein: The transition metal alloy catalyst is NiAl or NiFeAl or NiMoAl or NiFeCo or NiFeCoAl, the transition metal oxide catalyst is NiFe2O4Al or Ni(CoFe)2O4, the noble metal catalyst is PtAl or IrAl or RuAl, and the noble metal oxide catalyst is RuO2Al or IrO2Al.

4. The method for preparing a thermally sprayed nickel wire mesh electrode according to claim 1, wherein: The first catalyst or the second catalyst includes the following components in percentage by weight: Ni: 40-80%; Al：10～30%； One or more of Fe, Co, Mo, W: Fe: 5-40%; Co: 5-40%; Mo: 5-40%; W：5～40%； Catalyst alloy powder was prepared according to the above ingredients.

5. The method for preparing a thermally sprayed nickel wire mesh electrode according to claim 3, wherein: The first catalyst is NiFeCo, wherein the alloy ratio is Ni 80%, Fe 10%, Co 10%; The second catalyst is NiFeCo, wherein the alloy ratio is Ni 80%, Fe 10%, and Co 10%.

6. A nickel wire mesh electrode for producing hydrogen by alkaline water electrolysis, characterized in that: The nickel wire mesh electrode is prepared by the method for preparing the thermal sprayed nickel wire mesh electrode according to any one of claims 1 to 5.

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