CN114079059A - Oxygen reduction electrode structure and manufacturing method thereof - Google Patents
Oxygen reduction electrode structure and manufacturing method thereof Download PDFInfo
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- CN114079059A CN114079059A CN202010840862.0A CN202010840862A CN114079059A CN 114079059 A CN114079059 A CN 114079059A CN 202010840862 A CN202010840862 A CN 202010840862A CN 114079059 A CN114079059 A CN 114079059A
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- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/8647—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites
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- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/8663—Selection of inactive substances as ingredients for catalytic active masses, e.g. binders, fillers
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Abstract
The structure of the oxygen reduction electrode and the manufacturing method thereof comprise an electrode substrate and a conductive connecting end connected with the electrode substrate, wherein a surface catalyst layer of the oxygen reduction electrode is a transition metal compound layer formed by directly converting atoms on the outer surface of the transition metal substrate of the electrode substrate in situ. The transition metal compound layer is formed by a controlled atmosphere heat treatment method, a CVD method, a molten salt treatment method, a hydrothermal reaction method, an electrolysis method, or a magnetron sputtering method. The surface catalyst layer of the oxygen reduction electrode of the present invention has a highly stable structure and has a very firm bond with the transition metal substrate, which ensures the long life and efficiency of the oxygen reduction electrode.
Description
Technical Field
The invention belongs to the technical field of energy technology and materials, and particularly relates to a structure of an oxygen reduction electrode and a manufacturing method thereof.
Technical Field
At the oxygen reduction electrode is a reduction of oxygen molecules, wherein a catalyst is present which is capable of catalyzing the reduction of oxygen at the electrode. Oxygen reduction electrodes have found wide application in the battery and membrane electrode fields. The oxygen reduction electrode is also referred to as an air electrode because oxygen during use is in many cases derived from oxygen in the air. The traditional oxygen reduction electrode structure comprises a hydrophobic air-permeable layer, a current collector and a catalyst layer, wherein the catalyst layer is a composite material layer containing catalyst powder, conductive material (usually carbon material) powder and hydrophobic material, the hydrophobic air-permeable layer is a composite material layer containing conductive material powder and hydrophobic material, and the current collector is a conductive metal mesh. In the process of long-time discharging or cyclic charging and discharging, catalyst powder and conductive material powder in the catalytic layer are easy to fall off, and meanwhile, the catalytic layer is too thick, so that the internal resistance is higher, the electron transfer rate is slowed down, and the performance of the oxygen reduction electrode is reduced. The hydrophobic and breathable layer is easy to seep liquid due to the fact that the hydrophobic and breathable layer contains conductive material powder, and the service life of the oxygen reduction electrode is shortened. Because the hydrophobic breathable layer and the catalyst layer realize electron conduction through the conductive material powder, the electron transfer rate between the conductive material powder is slow, and the improvement of the performance of the oxygen reduction electrode is not facilitated.
The Chinese patent application "air electrode and its preparation method and application" (CN 201911211905.2) proposes a preparation method of air electrode, its manufacturing step includes: 1) preparing gas diffusion slurry by using carbon powder, industrial alcohol and Polytetrafluoroethylene (PTFE) emulsion; 2) forming a gas diffusion film on the gas diffusion slurry on one side of the current collector; 3) preparing catalytic slurry by utilizing carbon powder, industrial alcohol, a catalyst, a pore-forming agent and PTFE emulsion, wherein the pore-forming agent is selected from any one of ammonium oxalate, ammonium bicarbonate, polyethylene glycol 200 and polyvinyl alcohol; 4) forming the catalytic slurry into a catalytic film on the other side of the current collector; 5) and sintering the current collectors respectively provided with the gas diffusion film and the catalytic film on the two sides to prepare the air electrode, wherein the air electrode has higher porosity, longer electrode life and better electrical property. In addition, the invention also provides an air electrode prepared by the preparation method of the air electrode and application of the air electrode in the field of membrane electrodes. It can be seen that the air electrode proposed in this patent application is composed of a current collector and a gas diffusion membrane and a catalytic membrane respectively located on both sides of the current collector. The carbon powder in the gas diffusion membrane and the carbon powder and the catalyst powder in the catalytic membrane are all wrapped in a network structure formed by PTFE emulsion. In the long-time discharging or circulating charging and discharging process, catalyst powder and carbon powder in the catalytic membrane are easy to fall off, and meanwhile, the catalytic layer is too thick, so that the internal resistance is high, the electron transfer rate is slow, and the performance of the oxygen reduction electrode is reduced. The hydrophobic and breathable layer is easy to seep liquid due to the fact that the hydrophobic and breathable layer contains conductive material powder, and the service life of the oxygen reduction electrode is shortened. Because the hydrophobic breathable layer and the catalyst layer realize electron conduction through the conductive material powder, the electron transfer rate between the conductive material powder is slow, and the improvement of the performance of the oxygen reduction electrode is not facilitated.
The Chinese invention patent application (CN 202010004690.3) provides an air electrode for a metal-air battery and a preparation method thereof. Mixing the metal organic framework material with nitrogen source small molecules to enable the nitrogen source small molecules to be adsorbed in the metal organic framework; then carrying out high-temperature carbonization treatment in a nitrogen atmosphere, and finally carrying out acid treatment to remove metal particles to obtain the nitrogen-doped porous carbon material; preparing the porous carbon material into slurry, and coating the slurry on the surface of a conductive substrate to obtain the air electrode for the metal-air battery. Uniformly mixing the nitrogen-doped porous carbon and a binder according to a preset mass ratio to obtain conductive slurry; and then spraying the conductive slurry on a conductive substrate, and pressing a layer of polytetrafluoroethylene film on the substrate to obtain the air electrode. The nitrogen-doped porous carbon material can catalyze oxygen reduction reaction on the electrode, and the porous carbon material also has a conductive function. Therefore, the catalytic layer is formed by mixing nitrogen-doped porous carbon and a binder and is attached to the conductive substrate. Since the binder does not have conductivity, the catalyst layer formed by mixing the nitrogen-doped porous carbon and the binder has poor conductivity, and the performance of the air electrode is reduced. During long-time discharging or cyclic charging and discharging, the nitrogen-doped porous carbon powder in the catalytic membrane is easy to separate from the binder and fall off, and the performance of the air electrode is also reduced. The polytetrafluoroethylene film has good hydrophobic property, but has poor air permeability, which is not beneficial to improving the performance of the air electrode.
Disclosure of Invention
In order to solve the defects of the prior art, the invention provides an oxygen reduction electrode structure which comprises an electrode base body and a conductive connecting end connected with the electrode base body. The surface catalyst layer of the oxygen reduction electrode is a transition metal compound layer formed by directly converting atoms on the outer surface of a transition metal substrate of the electrode substrate in situ.
Further, the air conditioner is provided with a fan,
the method for directly converting the atoms into the transition metal compound in situ includes a method of controlled atmosphere heat treatment, a CVD method, a molten salt treatment method, a hydrothermal reaction method, an electrolysis method, or a magnetron sputtering method.
The electrode substrate comprises a transition metal substrate structure made of transition metal only, or a transition metal substrate structure attached to the conductive metal sheet, or a transition metal substrate structure wrapping the conductive metal sheet; the outer surface of the transition metal substrate is completely or partially covered with a surface catalyst layer; and an anti-corrosion layer is arranged on the outer surface of the electrode substrate which is not covered by the surface catalyst layer.
The outer surface of the transition metal matrix presents an uneven structure; the uneven height difference of the outer surface of the transition metal layer is in the range of 1nm-1 mm.
The surface catalyst layer on the outer surface of the transition metal matrix is also provided with zero-dimensional or one-dimensional or both zero-dimensional and one-dimensional nano structures.
The electrode substrate comprises a nonporous structure and a porous structure; and a surface catalyst layer is attached to the outer surface of the transition metal substrate on the inner wall of the through hole of the porous structure electrode substrate.
The transition metal matrix is a single transition metal element or an alloy of two or more transition metal elements, or an alloy formed by the transition metal element and other non-transition metal elements; the transition metal element comprises metal manganese, metal iron, metal cobalt or metal nickel.
The transition metal compound of the catalyst layer is a nitride of the transition metal, or an oxide of the transition metal, or a carbide of the transition metal, or a mixture of two or three of the transition metal, which is directly converted in situ by atoms on the surface of a transition metal substrate; the thickness of the catalyst layer is 1nm-100 mu m.
Arranging a breathable hydrophobic layer on the outer surface of one end of the through hole of the porous structure electrode substrate to form a composite structure oxygen reduction electrode; the thickness of the breathable hydrophobic layer is in the range of 0.1 mu m-2 mm; the material of the breathable hydrophobic layer is a high polymer material.
In order to solve the problems in the prior art, the invention also provides a manufacturing method of the oxygen reduction electrode, which comprises the following steps:
1) an electrode substrate constructed with a transition metal substrate;
2) converting the outer surface of the transition metal substrate, on which the surface catalyst layer is required to be formed, into a nitride of a transition metal, or an oxide of the transition metal, or a carbide of the transition metal, or a mixture of two or three of the above by using a controlled atmosphere heat treatment method, a CVD method, a molten salt treatment method, a hydrothermal reaction method, an electrolysis method or a magnetron sputtering method;
3) connecting the electrode substrate with the conductive connecting end, and if the electrode substrate and the conductive connecting end are in an integrated structure, omitting the step;
4) an oxygen reduction electrode is manufactured by coating a corrosion-proof layer on a portion of an electrode substrate requiring corrosion protection. Further, the air conditioner is provided with a fan,
the electrode substrate constructed with the transition metal substrate comprises an electrode substrate which is made of conductive transition metal and has a porous or nonporous structure; or forming a layer of transition metal matrix on the required positions of the inner and outer surfaces of the non-porous or porous conductive metal sheet by adopting a PVD method, a CVD method, an electro-deposition method, a magnetron sputtering method or a thermal spraying method to prepare the electrode matrix.
The method also comprises the steps of selecting the oxygen reduction electrode with the porous structure, adhering a polymer material layer with the air-permeable and hydrophobic functions on the surface of one side of the oxygen reduction electrode with the porous structure, which needs to permeate oxygen, by adopting a binder or a hot pressing method, and realizing tight combination between the polymer material layer and the oxygen reduction electrode, or coating a polymer material coating with the air-permeable and hydrophobic functions on the surface of the one side, thereby manufacturing the air electrode with the composite structure.
Compared with the prior art, the invention has the following advantages:
1) the catalyst of the oxygen reduction electrode of the present invention is a nitride of a transition metal, or an oxide of a transition metal, or a carbide of a transition metal, or a mixture of two or three of the above. The catalyst is covered on the surface of a transition metal substrate in a thin film structure to form a surface catalyst layer. Because the surface catalyst layer is formed by directly converting atoms on the surface of the transition metal substrate, the surface catalyst layer completely covers the surface of the air electrode without gaps, the highest density distribution of the catalyst on the surface of the oxygen reduction electrode is ensured, and the high activity of the oxygen reduction electrode is also ensured. Meanwhile, the surface catalyst layer formed in the way has a highly stable structure and is firmly combined with the transition metal substrate, so that the long service life of the oxygen reduction electrode is ensured.
2) The surface catalyst layer in the oxygen reduction electrode is formed by directly converting atoms on the surface of the transition metal substrate, and the surface catalyst layer is firmly combined with the transition metal substrate, so that the electron transmission efficiency between the surface catalyst layer and the transition metal substrate is greatly improved. For an air electrode taking a transition metal matrix as a current collector, the performance of the oxygen reduction electrode can be obviously improved through efficient electron transmission between the catalyst and the transition metal matrix. For the oxygen reduction electrode provided with the conductive metal sheet, the transition metal substrate and the conductive metal sheet serving as the current collector are tightly combined to form a high-efficiency conductive passage between the surface catalyst layer and the conductive metal sheet serving as the current collector, so that the performance of the oxygen reduction electrode is obviously improved.
3) The invention adopts a connecting agent or a hot-pressing fusion method to adhere the breathable hydrophobic layer on one side surface of the oxygen reduction electrode with the porous structure, thereby not only greatly simplifying the manufacturing process, but also effectively preventing the electrolyte from permeating while ensuring the oxygen permeation of the macromolecular breathable hydrophobic layer, and ensuring the long service life of the oxygen reduction electrode with the composite structure.
The oxygen reduction electrode of the present invention can be used not only as the positive electrode of a battery, but also as an electrode for membrane electrodes and other electrocatalytic processes.
Drawings
FIG. 1 is a schematic cross-sectional view of an oxygen reduction electrode formed of a non-porous transition metal substrate according to a first embodiment.
FIG. 2 is a schematic cross-sectional view of an oxygen reduction electrode comprising a non-porous transition metal substrate according to an embodiment. Wherein the surface catalyst layer 2 completely wraps the entire surface of the transition metal substrate without a gap.
FIG. 3 is a schematic cross-sectional view of an oxygen reduction electrode composed of a porous electrode substrate made of a transition metal material according to a second embodiment.
FIG. 4 is a schematic cross-sectional view of an oxygen reduction electrode having a non-porous structure in the third example. Wherein, the transition metal matrix 1 covers part of the surface of the non-porous structure conductive metal sheet and is tightly combined with the non-porous structure conductive metal sheet.
FIG. 5 is a schematic sectional structure view of the oxygen-reducing electrode having a porous structure in the fourth example. Wherein, a plurality of through holes are distributed in the porous structure conductive metal sheet, and the inner surface and the outer surface of the conductive metal sheet are wrapped by the transition metal matrix.
FIG. 6 is a schematic cross-sectional view of an oxygen reduction electrode having a porous composite structure according to example V.
Reference is made to the accompanying drawings in which:
1. transition metal matrix
1-1, non-porous structure transition metal matrix
1-2 transition metal matrix with porous structure
1-2-1 pores in a transition metal matrix of porous structure
2. Surface catalyst layer
2-1, zero-dimensional nano structure on surface of catalyst layer
2-2, one-dimensional nanostructure on surface of catalyst layer
2-3, catalyst layer on the surface of inner wall of hole
3. Anti-corrosion layer
4. Conductive connection terminal
5. Conductive metal sheet
5-1 non-porous structure conductive metal sheet
5-2 porous structure conductive metal sheet
5-2-1 pores in a porous structured conductive metal sheet
6. A gas-permeable hydrophobic layer.
Detailed Description
Example 1: a non-porous structure oxygen reduction electrode as shown in FIG. 1a comprises a non-porous structure transition metal substrate 1-1 composed of only transition metal, a surface catalyst layer 2 and an electrically conductive connection terminal 4. Wherein, the surface catalyst layer 2 covers part of the surface of the transition metal substrate 1-1 without gaps and is tightly combined with the surface, and the conductive connecting end 4 is in conductive connection with the electrode substrate made of the transition metal material.
The electrode substrate composed of the non-porous transition metal substrate 1-1 has double functions of an oxygen reduction electrode current collector and a surface catalyst layer. The electrode substrate is a non-porous structure, and the surface of the transition metal layer constituting the electrode substrate exhibits irregularities to increase the surface area. The height difference of the unevenness on the surface of the transition metal layer 1-1 is in the range of 1nm-1 mm. The transition metal layer may be a single transition metal element or an alloy of two or more transition metal elements, or an alloy of a transition metal element and other non-transition metal elements. The best choice of the material of the transition metal electrode layer is metal manganese, or metal iron, or metal cobalt, or metal nickel.
The surface catalyst layer 2 functions to catalyze the oxygen reduction reaction at the surface of the electrode. The surface catalyst layer 2 covers the outer surface of the transition metal substrate 1-1 without gaps, and means that the surface catalyst layer 2 is a transition metal nitride, a transition metal oxide, a transition metal carbide or a mixture of two or three of the above, which is directly converted in situ from transition metal atoms on the surface of the transition metal substrate 1-1. The surface catalyst layer 2 directly converted from atoms on the surface of the non-porous structure transition metal substrate 1-1 completely covers the entire surface of the non-porous structure transition metal substrate 1-1 without gaps. The surface catalyst layer 2 is tightly combined with the non-porous transition metal substrate 1-1. The nitride of the transition metal, or the oxide of the transition metal, or the carbide of the transition metal, or the mixture of two or three of them, which constitutes the surface catalyst layer 2, is an oxygen reduction catalyst, that is, the surface of the non-porous structure transition metal substrate 1-1 is entirely covered with the oxygen reduction catalyst. The thickness of the surface catalyst layer is in the range of 1nm to 100 [ mu ] m.
The function of the conductive connecting end 4 is to realize the conductive connection between the electrode substrate and an external circuit. The conductive connecting end 4 and the non-porous transition metal matrix 1-1 are of an integrated structure, and the conductive connecting end 4 and the non-porous transition metal matrix are integrally formed by adopting the same material.
If necessary, a corrosion prevention layer 3 may be provided on the surface of the non-porous structure transition metal substrate 1-1 not covered with the surface catalyst layer (FIG. 1 b). The anti-corrosion layer has the functions of preventing or delaying the corrosion of the oxygen reduction electrode in the electrolyte and ensuring the long service life of the oxygen reduction electrode. The anti-corrosion layer is arranged on the surface of the non-porous structure transition metal substrate 1-1 without the surface catalyst layer and is tightly combined with the surface of the non-porous structure transition metal substrate 1-1.
As shown in fig. 2, a surface catalyst layer 2 may be further provided on all outer surfaces of the non-porous structure transition metal substrate 1-1 to further increase the area of the surface catalyst layer of the oxygen reduction electrode.
As shown in FIG. 2, a large number of protruding zero-dimensional nanostructures 2-1 and one-dimensional nanostructures 2-2 may be further formed on the surface of the catalyst layer 2 having the uneven surface to more effectively improve the performance of the oxygen reduction electrode.
Example 2: a porous-structure oxygen reduction electrode composed of a porous-structure transition metal substrate 1-2 is shown in FIG. 3, in which the surface of the porous-structure transition metal substrate 1-2 has an uneven structure. The present embodiment is different from the electrode shown in fig. 2 in embodiment 1 in that a plurality of through holes 1-2-1 are distributed in the transition metal substrate, and the material of the conductive connection terminal 4 is different from that of the transition metal substrate. The end of the conductive connecting end 4 is conductively connected with the end of the transition metal matrix 1. The inner and outer surfaces of the transition metal matrix 1-2 with the porous structure are completely covered by the surface catalyst layer 2, so that the surface area of the surface catalyst layer is increased, an oxygen diffusion channel is provided, and the performance of the oxygen reduction electrode is further improved.
Example 3: as shown in FIG. 4a, there is provided a non-porous structure oxygen reduction electrode comprising a non-porous structure transition metal substrate 1-1, a surface catalyst layer 2, a non-porous structure conductive metal sheet 5-1 and a conductive connection terminal 4. The conductive metal sheet is of a non-porous structure, the non-porous structure transition metal substrate 1-1 covers part of the surface of the non-porous structure conductive metal sheet 5-1 and is tightly combined with the non-porous structure conductive metal sheet, and the surface catalyst layer 2 completely covers the surface of the transition metal substrate 1 without gaps and is tightly combined with the non-porous structure conductive metal sheet. The conductive connecting end 4 and the non-porous conductive metal sheet 5-1 are of an integrated structure and made of the same material.
Similar to example 1, the surface of the non-porous structure transition metal substrate 1-1 exhibits an uneven structure to increase the surface area. The uneven height difference of the surface of the non-porous transition metal matrix 1-1 is in the range of 1nm-1 mm. The non-porous structure transition metal substrate 1-1 of the present embodiment has dual functions of forming the surface catalyst layer 2 and achieving conductive connection between the surface catalyst layer 2 and the non-porous structure conductive metal sheet 5-1.
The function and structure of the surface catalyst layer 2 are the same as those of embodiment 1.
The non-porous conductive metal sheet 5-1 has a function of serving as a current collector of an oxygen reduction electrode and has good conductivity. The conductive metal sheet has a non-porous structure. The conductive metal sheet is tightly connected with the non-porous transition metal matrix 1-1 on the surface of the conductive metal sheet.
The function of the conductive connecting end 4 is to realize the conductive connection between the non-porous conductive metal sheet 5-1 and an external circuit. The conductive connecting end 4 and the non-porous conductive metal sheet 5-1 are made of the same material and are of an integrated structure.
If necessary, the corrosion prevention layer 3 (shown in fig. 4 b) may be provided on the surface of the non-porous structure conductive metal sheet 5-1 on which the transition metal substrate 1 is not provided.
Example 4: as shown in FIG. 5, the porous structure oxygen reduction electrode is composed of a transition metal substrate 1, a surface catalyst layer 2, a porous structure conductive metal sheet 5-2 and a conductive connection end 4. Wherein, a plurality of through holes 5-2-1 are distributed in the porous structure conductive metal sheet 5-2. The transition metal substrate 1 covers and is tightly combined with the inner and outer surfaces of the porous structure conductive metal sheet 5-2, and the surface catalyst layer 2 covers and is tightly combined with the surface of the transition metal substrate 1 without gaps. The conductive connecting end 4 is made of a material different from that of the porous structure conductive metal sheet 5-2, and one end of the conductive connecting end 4 is connected with one end of the porous structure conductive metal sheet 5-2 to realize conductive connection. The surface of the transition metal substrate 1 has an uneven structure to increase the surface area.
Example 5: fig. 6 is a schematic cross-sectional structural view of a composite structure oxygen reduction electrode composed of a transition metal substrate 1, a surface catalyst layer 2, a porous structure conductive metal sheet 5-2, a gas-permeable hydrophobic layer 6 and a conductive connection end 4. The difference from example 4 is that a gas-permeable hydrophobic layer 6 is provided on one side of the porous-structure oxygen-reducing electrode. The function of the gas-permeable hydrophobic layer 6 is to ensure that oxygen can reach the surface catalyst layer 2 on the surface of the transition metal substrate 1 via the gas-permeable hydrophobic layer, while preventing electrolyte present at the surface catalyst layer 2 from seeping out of the gas-permeable hydrophobic layer 6. The air-permeable hydrophobic layer 6 is tightly combined with the porous structure oxygen reduction electrode. The air-permeable hydrophobic layer 6 is made of a high polymer material with a micro-channel structure. The thickness of the breathable hydrophobic layer is in the range of 0.1 mu m-2 mm.
Similarly, a gas-permeable hydrophobic layer 6 may be provided on the side of the porous-structure oxygen-reducing electrode on which the conductive metal sheet is not provided, to form a composite-structure oxygen-reducing electrode.
Example 6: a method for manufacturing a porous structure oxygen reduction electrode without a conductive metal sheet, comprising the steps of:
the first step is as follows: selecting a transition metal matrix with a porous structure, wherein the transition metal matrix and the conductive connecting end adopt an integrated structure, and coating a high-temperature-resistant anti-oxidation material on the conductive connecting end;
the second step is that: converting atoms on the inner surface and the outer surface of a transition metal matrix with a porous structure into nitrides of the transition metal by adopting a CVD (chemical vapor deposition) method in an atmosphere containing nitrogen elements, wherein the thickness of the nitrides is 1nm-100 mu m;
the third step: and removing the high-temperature-resistant oxidation-resistant material coated on the conductive connecting end.
The fourth step: if necessary, a corrosion-preventing layer is applied to a portion where corrosion prevention is required, thereby producing a porous structure oxygen reduction electrode.
Similarly, a non-porous structure transition metal substrate can be selected, and the non-porous structure oxygen reduction electrode can be manufactured through the four steps.
The atoms on the inner and outer surfaces of the porous transition metal matrix may be converted into nitrides of the transition metals by a controlled atmosphere heat treatment method, a molten salt treatment method, a hydrothermal reaction method, or an electrolysis method.
Similarly, atoms located on the inner and outer surfaces of the porous-structure transition metal matrix may be converted into oxides of the transition metal in an atmosphere containing an oxygen element; or in the atmosphere containing carbon element, converting the atoms positioned on the inner surface and the outer surface of the transition metal matrix with the porous structure into the carbide of the transition metal; or converting atoms located on the inner and outer surfaces of the porous-structure transition metal substrate into a mixture of a nitride and an oxide of the transition metal in an atmosphere containing a nitrogen element and an oxygen element; or converting atoms located on the inner and outer surfaces of the porous structure transition metal matrix into a mixture of carbides and nitrides of the transition metal in an atmosphere containing nitrogen elements and carbon elements; or converting atoms on the inner and outer surfaces of the porous transition metal matrix into a mixture of carbides and oxides of the transition metal in an atmosphere containing carbon and oxygen; or converting atoms located on the inner and outer surfaces of the porous-structure transition metal matrix into a mixture of nitrides, carbides and oxides of the transition metal in an atmosphere containing nitrogen, carbon and oxygen.
Example 7: a method of manufacturing a porous structure oxygen reduction electrode provided with a conductive metal sheet, comprising the steps of:
the first step is as follows: selecting a conductive metal sheet having a porous structure;
the second step is that: a layer of transition metal matrix is manufactured at the required positions of the inner and outer surfaces of the porous structure conductive metal sheet by adopting a magnetron sputtering method;
the third step: converting transition metal atoms on the inner surface and the outer surface of a transition metal matrix into a mixture of nitrides and carbides of the transition metal by adopting a CVD method in an atmosphere containing nitrogen elements and carbon elements, wherein the thicknesses of the nitrides and the carbides are 1nm-100 mu m;
the fourth step: for the conductive metal sheet and the conductive connecting end which are made of different materials, welding one end of the conductive metal sheet and one end of the conductive connecting end together to realize conductive connection;
the fifth step: if necessary, a corrosion-preventing layer is applied to a portion where corrosion prevention is required, thereby producing a porous structure oxygen reduction electrode.
Similarly, a non-porous structure conductive metal sheet can be selected, and the non-porous structure oxygen reduction electrode can be manufactured through the above five steps. If the conductive metal sheet and the conductive connection terminal are made of the same material, the fourth step can be omitted, but before the third step CVD, a high temperature resistant oxidation resistant material is applied to the conductive connection terminal.
Similarly to example 6, a mixture of nitride and oxide, or a mixture of oxide and carbide, or a mixture of nitride, oxide and carbide can be produced on the inner and outer surfaces of the transition metal substrate by controlling different atmospheres of CVD.
Similarly to example 6, atoms on the inner and outer surfaces of the porous-structure transition metal matrix may be converted into nitrides, oxides, carbides, or mixtures of two or three of the foregoing by a controlled atmosphere heat treatment method, a molten salt treatment method, a hydrothermal reaction method, or an electrolysis method.
Example 8: a method of manufacturing a composite structure oxygen reduction electrode comprising the steps of:
the first step is as follows: selection of the porous oxygen reduction electrode of one of the preceding examples
The second step is that: and adhering the air-permeable hydrophobic layer on one side surface of the oxygen reduction electrode with the porous structure by adopting a binder adhesion method and tightly combining the air-permeable hydrophobic layer, thereby manufacturing the oxygen reduction electrode with the composite structure. The thickness of the breathable hydrophobic layer is in the range of 0.1 mu m-2 mm.
The method of hot-pressing fusion can also be adopted, and the air-permeable hydrophobic layer is pressed on one side surface of the oxygen reduction electrode with the porous structure which needs to transmit oxygen and is tightly combined, so that the oxygen reduction electrode with the composite structure is manufactured. Or coating or spraying a layer of breathable hydrophobic polymer coating on the surface of one side of the porous structure oxygen reduction electrode needing to permeate oxygen to manufacture the composite structure oxygen reduction electrode.
Claims (12)
1. The structure of the oxygen reduction electrode comprises an electrode base body and a conductive connecting end connected with the electrode base body, and is characterized in that:
the surface catalyst layer of the oxygen reduction electrode is a transition metal compound layer formed by directly converting atoms on the outer surface of a transition metal substrate of the electrode substrate in situ.
2. The method of manufacturing an oxygen-reducing electrode structure according to claim 1, characterized in that:
the method for directly converting the atoms into the transition metal compound in situ includes a method of controlled atmosphere heat treatment, a CVD method, a molten salt treatment method, a hydrothermal reaction method, an electrolysis method, or a magnetron sputtering method.
3. The structure of an oxygen-reducing electrode according to claim 1, characterized in that:
the electrode substrate comprises a transition metal substrate structure made of transition metal only, or a transition metal substrate structure attached to the conductive metal sheet, or a transition metal substrate structure wrapping the conductive metal sheet; the outer surface of the transition metal substrate is completely or partially covered with a surface catalyst layer; and an anti-corrosion layer is arranged on the outer surface of the electrode substrate which is not covered by the surface catalyst layer.
4. The structure of the oxygen-reducing electrode according to claim 1 or 3, characterized in that:
the outer surface of the transition metal matrix presents an uneven structure; the uneven height difference of the outer surface of the transition metal layer is in the range of 1nm-1 mm.
5. The structure of an oxygen-reducing electrode according to claim 1, characterized in that:
the surface catalyst layer on the outer surface of the transition metal matrix is also provided with zero-dimensional or one-dimensional or both zero-dimensional and one-dimensional nano structures.
6. The structure of an oxygen-reducing electrode according to claim 1, characterized in that:
the electrode substrate comprises a nonporous structure and a porous structure; and a surface catalyst layer is attached to the outer surface of the transition metal substrate on the inner wall of the through hole of the porous structure electrode substrate.
7. The structure of an oxygen-reducing electrode according to claim 1, characterized in that:
the transition metal matrix is a single transition metal element or an alloy of two or more transition metal elements, or an alloy formed by the transition metal element and other non-transition metal elements; the transition metal element comprises metal manganese, metal iron, metal cobalt or metal nickel.
8. The structure of an oxygen-reducing electrode according to claim 1, characterized in that:
the transition metal compound of the catalyst layer is a nitride of the transition metal, or an oxide of the transition metal, or a carbide of the transition metal, or a mixture of two or three of the transition metal, which is directly converted in situ by atoms on the surface of a transition metal substrate; the thickness of the catalyst layer is 1nm-100 mu m.
9. The structure of an oxygen-reducing electrode according to claim 6, characterized in that:
arranging a breathable hydrophobic layer on the outer surface of one end of the through hole of the porous structure electrode substrate to form a composite structure oxygen reduction electrode; the thickness of the breathable hydrophobic layer is in the range of 0.1 mu m-2 mm; the material of the breathable hydrophobic layer is a high polymer material.
10. A method for manufacturing an oxygen reduction electrode comprises the following steps:
1) an electrode substrate constructed with a transition metal substrate;
2) converting the outer surface of the transition metal substrate, on which the surface catalyst layer is required to be formed, into a nitride of a transition metal, or an oxide of the transition metal, or a carbide of the transition metal, or a mixture of two or three of the above by using a controlled atmosphere heat treatment method, a CVD method, a molten salt treatment method, a hydrothermal reaction method, an electrolysis method or a magnetron sputtering method;
3) connecting the electrode substrate with the conductive connecting end, and if the electrode substrate and the conductive connecting end are in an integrated structure, omitting the step;
4) an oxygen reduction electrode is manufactured by coating a corrosion-proof layer on a portion of an electrode substrate requiring corrosion protection.
11. The method of manufacturing an oxygen-reducing electrode according to claim 10, wherein:
the electrode substrate constructed with the transition metal substrate comprises an electrode substrate which is made of conductive transition metal and has a non-porous or porous structure; or forming a layer of transition metal matrix on the required positions of the inner and outer surfaces of the non-porous or porous conductive metal sheet by adopting a PVD method, a CVD method, an electro-deposition method, a magnetron sputtering method or a thermal spraying method to prepare the electrode matrix.
12. A method for manufacturing an oxygen reduction electrode based on the composite structure of claim 10, characterized in that:
selecting an oxygen reduction electrode with a porous structure, adhering a polymer material layer with air-permeable and hydrophobic functions on one side surface of the oxygen reduction electrode with the porous structure needing to permeate oxygen by adopting a binder or a hot pressing method, and realizing tight combination between the polymer material layer and the oxygen reduction electrode, or coating a polymer material coating with air-permeable and hydrophobic functions on the one side surface, thereby manufacturing the air electrode with a composite structure.
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| CN114725457A (en) * | 2022-03-29 | 2022-07-08 | 上海交通大学 | Method for preparing membrane electrode for accelerating local oxygen mass transfer |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102447115A (en) * | 2010-12-31 | 2012-05-09 | 山东理工大学 | Novel magnesium air battery cathode |
| CN111056598A (en) * | 2018-10-17 | 2020-04-24 | 湖北大学 | Electrochemical oxygen catalytic reduction cathode material for water treatment and preparation method thereof |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102447115A (en) * | 2010-12-31 | 2012-05-09 | 山东理工大学 | Novel magnesium air battery cathode |
| CN111056598A (en) * | 2018-10-17 | 2020-04-24 | 湖北大学 | Electrochemical oxygen catalytic reduction cathode material for water treatment and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114725457A (en) * | 2022-03-29 | 2022-07-08 | 上海交通大学 | Method for preparing membrane electrode for accelerating local oxygen mass transfer |
| CN114725457B (en) * | 2022-03-29 | 2024-03-12 | 上海交通大学 | Membrane electrode preparation method for accelerating local oxygen mass transfer |
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