Self-suction water electrolysis hydrogen production capillary electrolytic cell

Abstract

The invention discloses a self-suction type water electrolysis hydrogen production capillary electrolytic bath and belongs to the technical field of water electrolysis hydrogen production. The capillary electrolytic bath comprises an electrolysis assembly and an electrolyte cavity which are connected through a capillary transmission layer, and the electrolysis assembly comprises a diaphragm, an anode unit arranged on one side of the diaphragm and a cathode unit arranged on one side of the diaphragm; electrolyte is stored in the electrolyte cavity, and the capillary transmission layer extends into the electrolyte in the electrolyte cavity and is connected with the electrolyte cavity and the electrolysis cavity of the electrolysis assembly. Therefore, the self-suction water electrolysis hydrogen production capillary electrolytic cell provided by the invention is applied to PEM water electrolysis hydrogen production and AEM water electrolysis hydrogen production. By means of the capillary transmission layer with the capillary phenomenon, the electrolyte is conveyed from the electrolyte cavity to the electrolysis anode cavity or the electrolysis cathode cavity, generated oxygen and hydrogen can be directly discharged without resistance, bubbles are not generated, and the problem that gas bubbles generated in the prior art block porous channels is solved.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen production by water electrolysis, and in particular to a self-priming capillary electrolyzer for hydrogen production by water electrolysis. Background Art

[0002] As a clean and efficient energy source, hydrogen energy is regarded as one of the main ways to achieve carbon peak and carbon neutrality. It has the following characteristics: high energy density, no pollution, wide sources, and can be stored and transported. With the growing global demand for clean energy and increasing attention to environmental protection, hydrogen energy has become an ideal clean energy and has received widespread attention. In the hydrogen production process, hydrogen production by electrolysis of water is regarded as "green hydrogen". During the electrolysis process, oxygen is produced at the anode and hydrogen is produced at the cathode. It has zero carbon emissions and is considered to be the cleanest energy. It is gradually becoming a highly anticipated hydrogen production technology.

[0003] At present, the electrolysis water hydrogen production technology is mainly divided into alkaline water electrolysis (ALK) hydrogen production technology, proton exchange membrane (PEM) water electrolysis water hydrogen production technology, anion exchange membrane (AEM) water electrolysis water hydrogen production technology and solid oxide (SOE) water electrolysis water hydrogen production technology. Among them, the alkaline water electrolysis water hydrogen production technology is the most mature water electrolysis water hydrogen production technology, which has been applied on a large scale. It uses alkaline solutions such as potassium hydroxide (KOH) or sodium hydroxide (NaOH) as electrolytes, and the cost of hydrogen production is low. However, the conventional alkaline water electrolysis water hydrogen production electrolyzer has a maximum hydrogen production efficiency of 75%. This is mainly because in the process of water electrolysis, the generated hydrogen and oxygen bubbles will adhere to the surrounding of the anode and cathode electrodes, thereby hindering the effective contact between the electrodes and the electrolyte. At the same time, the bubbles need to be discharged through the electrolyte, which reduces the electrolysis efficiency. Therefore, Aaron Hodges et al. developed a capillary electrolyzer [Aaron Hodges, AnhLinh Hoang, George Tsekouras, Klaudia Wagner, Chong-Yong Lee, Gerhard F.Swiegers&Gordon G.Wallace, Nature Communications 2022, 13: 1304]. In this capillary electrolyzer structure, the electrolyte (potassium hydroxide or sodium hydroxide solution) is supplied to the electrode through the capillary action of the porous diaphragm. During the electrolysis of water, the electrolyte is continuously transferred from the reservoir to the diaphragm for replenishment through capillary action. The electrode absorbs the liquid laterally from the diaphragm, and the hydrogen and oxygen generated by electrolysis at the cathode and anode are directly discharged without contacting the electrolyte and generating bubbles. This provides a bubble-free electrolysis method, and its hydrogen production efficiency by electrolysis of water is increased to 98%. CN202410907957.8 proposes a capillary self-priming seawater electrolysis hydrogen production device and method, which combines a seawater heat extraction and desalination component, and transmits the desalinated seawater to the electrode through the capillary action of a porous diaphragm, and produces hydrogen and oxygen by electrolysis. This method integrates the in-situ desalination of seawater and the electrolysis of water, and realizes the direct introduction of seawater into the electrolytic cell for electrolytic hydrogen production. The generated gas is directly discharged without generating bubbles, providing a bubble-free method for electrolyzing seawater, and improving the hydrogen production efficiency.

[0004] Proton exchange membrane (PEM) water electrolysis hydrogen production technology has been commercialized. It has the advantages of short start-up and shutdown time, high hydrogen purity, environmental friendliness, compact structure, and easy response to the volatility of renewable energy. The main components of the PEM electrolyzer are composed of a proton exchange membrane, a catalyst layer, a gas diffusion layer, and a bipolar plate from the inside to the outside. In the process of water electrolysis, the electrolyte water flows into the anode chamber through external pressure, is transmitted to the anode catalyst layer through the anode gas diffusion layer, and undergoes an oxidation reaction to generate hydrogen ions and oxygen. The generated oxygen is transmitted to the water through the anode gas diffusion layer and is discharged as bubbles, while the generated hydrogen ions are conducted to the cathode through the proton exchange membrane, and a reduction reaction occurs at the cathode to generate hydrogen, which is discharged through the cathode gas diffusion layer without generating hydrogen bubbles. In the process of PEM water electrolysis hydrogen production, the electrolyte only contacts the anode side, and oxygen bubbles are generated in the electrolyte, resulting in the problem of oxygen bubbles blocking the porous channels of the anode gas diffusion layer. Moreover, in the PEM electrolyzer structure, the anode gas diffusion layer also plays the role of liquid-gas transmission. The transmission direction of the electrolyte in the anode gas diffusion layer is opposite to the direction of generating gas oxygen, which hinders the discharge of oxygen and reduces the hydrogen production efficiency. The anode gas diffusion layer is mainly made of porous titanium and titanium felt because it is in an acidic environment.

[0005] Anion exchange membrane (AEM) water electrolysis hydrogen production technology is an emerging water electrolysis hydrogen production technology that combines the advantages of alkaline water electrolysis (ALK) hydrogen production technology and proton exchange membrane (PEM) water electrolysis hydrogen production technology: using non-precious metal catalysts in an alkaline working environment, the cost of electrolyzer components is low; it has a structure similar to that of a PEM electrolyzer, can match the volatility of renewable energy, has a compact structure, and produces high purity hydrogen. The main components of the AEM electrolyzer are composed of anion exchange membrane, catalyst layer, gas diffusion layer, and bipolar plate from the inside to the outside. The structure of the AEM electrolyzer is the same as that of the PEM electrolyzer, except that it uses anion exchange membrane, and the electrolyte of the AEM electrolyzer can be potassium hydroxide, sodium hydroxide solution or pure water. During the electrolysis process, the electrolyte is transported to the anode chamber, transmitted to the anode catalyst layer through the anode gas diffusion layer, then transmitted to the anion exchange membrane, and finally transmitted to the cathode catalyst layer. Under the action of the cathode catalyst, the electrolyte is decomposed into hydrogen and hydroxide ions. The generated hydrogen is discharged through the cathode gas diffusion layer without generating hydrogen bubbles, while the generated hydroxide ions are conducted to the anode through the anion exchange membrane, and an oxidation reaction occurs on the anode side to generate oxygen, which is then transmitted to the electrolyte through the anode gas diffusion layer and generated oxygen bubbles for discharge. Similar to the PEM water electrolysis hydrogen production, the AEM water electrolysis hydrogen production electrolyte only contacts the anode side and generates oxygen bubbles in the electrolyte. There is also the problem of oxygen bubbles blocking the porous channels of the anode gas diffusion layer. In the AEM electrolyzer structure, the anode gas diffusion layer also plays a role in liquid-gas transmission, and the transmission direction of the electrolyte in the anode gas diffusion layer is opposite to the direction of generating gas oxygen, which hinders the discharge of oxygen and reduces the hydrogen production efficiency. The anode gas diffusion layer of AEM water electrolysis hydrogen production is mainly made of porous nickel, porous titanium and other materials because it is in an alkaline environment.

[0006] Therefore, in the current PEM water electrolysis and AEM water electrolysis hydrogen production, during the water electrolysis process, the generated oxygen needs to be discharged by forming bubbles in the electrolyte, which can easily block the porous channels of the anode gas diffusion layer, and the transmission direction of the electrolyte in the anode gas diffusion layer is opposite to the discharge direction of the generated gaseous oxygen, which hinders the liquid-gas transmission efficiency of the anode gas diffusion layer and thus reduces the electrolysis efficiency. Summary of the invention

[0007] The purpose of the present application is to provide a self-priming capillary electrolyzer for hydrogen production by water electrolysis, which is applied to hydrogen production by water electrolysis by PEM and hydrogen production by water electrolysis by AEM. The electrolyte is transported from the electrolyte chamber to the electrolysis anode chamber or cathode chamber through a capillary transport layer with capillary phenomenon, and the generated oxygen and hydrogen can be discharged directly without resistance without generating bubbles, thus solving the problem of gas bubbles blocking the porous channels in the prior art.

[0008] The present invention provides a self-priming capillary electrolyzer for producing hydrogen by electrolyzing water. The capillary electrolyzer comprises an electrolytic component and an electrolyte chamber connected by a capillary transmission layer. The electrolytic component comprises a diaphragm, an anode unit arranged on one side of the diaphragm, and a cathode unit arranged on one side of the diaphragm. The electrolyte chamber stores electrolyte. The capillary transmission layer extends into the electrolyte in the electrolyte chamber, connecting the electrolyte chamber and the electrolytic chamber of the electrolytic component.

[0009] Preferably, when applied to PEM water electrolysis for hydrogen production, the diaphragm is a proton exchange membrane and the electrolyte is pure water; when applied to AEM water electrolysis for hydrogen production, the diaphragm is an anion exchange membrane and the electrolyte is one of potassium hydroxide solution, sodium hydroxide solution and pure water; The anode unit includes an anode plate, a capillary transmission layer arranged inside the anode plate, and an anode catalyst layer arranged inside the capillary transmission layer; the cathode unit includes a cathode plate, a cathode gas diffusion layer arranged inside the cathode plate, and a cathode catalyst layer arranged inside the cathode gas diffusion layer; the anode plate and the capillary transmission layer are sealed and connected through a capillary transmission layer sealing gasket; the cathode plate and the cathode gas diffusion layer are sealed and connected through a sealing gasket; Alternatively, the anode unit includes an anode plate, an anode gas diffusion layer arranged on the inner side of the anode plate, a capillary transport layer arranged on the inner side of the anode gas diffusion layer, and an anode catalyst layer arranged on the inner side of the capillary transport layer; the cathode unit includes a cathode plate, a cathode gas diffusion layer arranged on the inner side of the cathode plate, and a cathode catalyst layer arranged on the inner side of the cathode gas diffusion layer; the anode gas diffusion layer is sealed and connected to the anode plate via a sealing gasket, the capillary transport layer is connected to the anode gas diffusion layer via a capillary transport layer sealing gasket; the cathode plate is sealed and connected to the cathode gas diffusion layer via a sealing gasket.

[0010] Preferably, when applied to AEM electrolysis of water to produce hydrogen, the diaphragm is an anion exchange membrane, and the electrolyte is one of potassium hydroxide solution, sodium hydroxide solution, and pure water; the anode unit includes an anode plate, an anode gas diffusion layer arranged on the inner side of the anode plate, and an anode catalyst layer arranged on the inner side of the anode gas diffusion layer; the cathode unit includes a cathode plate, a capillary gas transmission layer arranged on the inner side of the cathode plate, and a cathode catalyst layer arranged on the inner side of the capillary gas transmission layer; the anode gas diffusion layer is connected to the anode plate through a sealing gasket, and the capillary transmission layer is connected to the cathode plate through a capillary transmission layer gasket.

[0011] Preferably, a hydrogen outlet is provided on the cathode plate, and an oxygen outlet is provided on the anode plate.

[0012] Preferably, gas flow channels are provided on both the anode plate and the cathode plate.

[0013] Preferably, when the capillary electrolytic cell is used alone, an insulating gasket is provided on the outer side of the anode plate, an anode end plate is provided on the outer side of the insulating gasket, and an insulating gasket is provided on the outer side of the cathode plate, and a cathode end plate is provided on the outer side of the insulating gasket; When multiple capillary electrolytic cell units are connected, an insulating gasket is arranged on the outside of the anode plate of the capillary electrolytic cell at one end, and an anode terminal plate is arranged on the outside of the insulating gasket, and an insulating gasket is arranged on the outside of the cathode plate of the capillary electrolytic cell at the other end, and a cathode terminal plate is arranged on the outside of the insulating gasket.

[0014] Preferably, the electrolyte chamber is located at the top or bottom of the electrolytic assembly; the oxygen outlet penetrates the insulating gasket and the anode end plate; the hydrogen outlet penetrates the insulating gasket and the cathode end plate; The cathode plate and the anode plate are made of one or more of titanium, stainless steel, and graphite; the cathode gas diffusion layer is made of carbon paper, one or more of porous titanium, porous nickel, and porous stainless steel; the catalyst in the cathode catalyst layer is one of platinum, nickel, NiMo, and NiP; the diaphragm is a proton exchange membrane or an anion exchange membrane; the catalyst in the anode catalyst layer is one of iridium dioxide and nickel-iron alloy; the capillary transport layer is one or more of capillary foam titanium, capillary foam nickel, and capillary foam stainless steel.

[0015] Preferably, the preparation method of the capillary transmission layer is as follows: Step 1: Heat and stir the metal powder and the binder to form a slurry; Step 2: soaking the organic foam in the slurry obtained in step 1, repeatedly soaking until the organic foam wraps the slurry, and placing it in the air to solidify; Step 3: placing the solidified organic foam wrapped with the slurry obtained in step 2 in a degreasing furnace, and performing degreasing treatment under vacuum conditions or inert gas protection conditions to remove the organic foam and the binder, thereby obtaining a powder; Step 4: placing the powder in a vacuum furnace and subjecting it to vacuum sintering to obtain a porous material; Step 5: The porous material is surface treated to obtain a porous transmission layer.

[0016] Preferably, in step 1, the metal powder is one of titanium, nickel and stainless steel, and the particle size of the metal powder is less than 300 μm; the binder is paraffin; the heating temperature is 50-70 o C; The volume ratio of metal powder and binder is: 1:3-3:1; Step 2: the organic foam material is one of polyurethane, polyvinyl chloride and polystyrene, the porosity of the organic foam is between 50% and 99%, the pore size is less than 1 mm, and the through-porosity is 98% to 100%; The degreasing conditions in step 3 are: vacuum degree 10 -2 ~10 -5Pa or inert gas is argon, degreasing temperature is 200~800 o C, keep warm for 1-8 hours; The sintering conditions in step 4 are: vacuum degree 10 -2 ~10 -5 Pa, sintering temperature is 800~1400 o C, keep warm for 1-4 hours; In the surface treatment of step 5, when the metal powder is titanium, porous titanium is anodized, and when the metal powder is nickel, porous nickel is plasma treated. The conditions for anodizing porous titanium are: the electrolyte contains fluorine electrolyte, the porous titanium anode, the platinum cathode, a constant voltage is applied, and the temperature is 0-50 o C water bath, anodizing treatment for 1-60 minutes; plasma treatment of porous nickel conditions: vacuum degree 10 -2 ~10 -5 Pa, power 10-1000 watts, treatment time 1-30 minutes.

[0017] Preferably, the pore size of the fine transmission layer is less than 1 mm, the porosity is between 30% and 99%, and the through-porosity is 50% to 100%.

[0018] Therefore, the present application provides a self-priming water electrolysis hydrogen production capillary electrolyzer, which has the following beneficial effects: 1) The self-priming water electrolysis hydrogen production capillary electrolyzer structure provided by the present invention and the preparation method of the capillary transport layer thereof select an organic foam with capillary phenomenon as a template, wrap a metal slurry onto the organic foam, and after degreasing and sintering, a porous metal material similar to the organic foam capillary channel can be replicated, and the hydrophilicity of the porous metal material is improved through surface treatment, so that the prepared porous transport layer has a capillary effect.

[0019] 2) The self-priming capillary electrolyzer structure for hydrogen production by water electrolysis provided by the present invention can be applied to hydrogen production by PEM water electrolysis and hydrogen production by AEM water electrolysis. The electrolyte is transmitted by the capillary action of the capillary transmission layer, and the generated gas can be discharged directly without resistance without forming bubbles in the electrolyte, thereby avoiding the problem of bubbles clogging the porous channels of the gas diffusion layer during the water electrolysis process. A bubble-free method for hydrogen production by PEM water electrolysis and hydrogen production by AEM water electrolysis is provided, and during the electrolysis process, the transmission direction of the electrolyte is perpendicular to the direction of gas generated by the reaction, thereby accelerating the liquid-gas transmission efficiency and improving the hydrogen production efficiency of the electrolyzer.

[0020] 3) Compared with the PEM electrolyzer and AEM electrolyzer in the prior art, the self-priming capillary electrolyzer structure for producing hydrogen by electrolysis provided by the present invention has no electrolyte chamber in the electrolysis unit, and the electrolyte is evenly transmitted to the electrolysis reaction zone through the capillary transport layer, and there is no dead zone for electrolysis reaction. It is unnecessary to design and process the anode and cathode plate flow channels, which reduces the processing cost of the anode and cathode plates, and further reduces the cost of the electrolyzer, thereby providing a flow channel-free method for producing hydrogen by electrolysis of water.

[0021] 4) The self-priming water electrolysis hydrogen production capillary electrolyzer structure provided by the present invention is used to transfer the electrolyte to the electrolysis reaction zone through the capillary action of the capillary transmission layer, and no additional pressure is required to transfer the electrolyte. Compared with the PEM electrolyzer and AEM electrolyzer in the prior art, it saves energy to transfer the electrolyte. In addition, the self-priming water electrolysis hydrogen production capillary electrolyzer structure provided by the present invention has a simple structure, a high degree of integration, and a small footprint, and is suitable for wide industrial promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a front structural cross-sectional view of the electrolytic cell of Embodiment 1 and Embodiment 4 of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the electrolytic cell of the present invention; Figure 3 It is an exploded schematic diagram of the electrolytic cell electrolytic component structure of Embodiment 1 and Embodiment 4 of the present invention; Figure 4 This is a front structural cross-sectional view of an electrolytic cell in which the electrolyte chamber is located on the upper side of an electrolytic component according to Example 2 of the present invention; Figure 5 It is a front structural cross-sectional view of the electrolytic cell of Embodiment 3 and Embodiment 6 of the present invention; Figure 6 This is a front structural cross-sectional view of an AEM electrolytic cell in which the electrolyte is transported to the cathode chamber through a capillary transport layer according to Example 5 of the present invention; Figure 7 This is the microscopic morphology of the cross section of the capillary transport layer of the electrolytic cell in Example 1 of the present invention.

[0023] Among them, 1. electrolytic assembly; 2. electrolyte chamber; 3. anode plate; 4. anode gas diffusion layer; 5. capillary transport layer; 6. anode catalyst layer; 7. diaphragm; 8. cathode catalyst layer; 9. cathode gas diffusion layer; 10. cathode plate; 11. oxygen outlet; 12. hydrogen outlet; 13. anode plate flow channel; 14. cathode plate flow channel; 15. anode end plate; 16. cathode end plate; 17. insulating gasket; 18. sealing gasket; 19. capillary transport layer sealing gasket; 20. electrolyte. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further illustrated by the following examples.

[0025] Example 1 A self-priming water electrolysis hydrogen production capillary electrolyzer structure, applied to PEM water electrolysis hydrogen production such as Figure 1 As shown, the electrolytic cell comprises an electrolytic component 1 and an electrolyte chamber 2. The components of the electrolytic cell are arranged in order. Figure 1 Assemble.

[0026] In the electrolysis assembly 1, the diaphragm 7 is a proton exchange membrane, and an anode unit is provided on one side of the proton exchange membrane, and a cathode unit is provided on the other side thereof. The anode unit undergoes an oxidation reaction, and the cathode unit undergoes a reduction reaction. In the anode unit, the anode plate 3 is made of titanium, and is provided with an anode plate flow channel 13 and an oxygen outlet 11. The anode plate 3 plays the role of conducting electrons and transmitting gas; a capillary transport layer 5 is provided on the inner side of the anode plate 3, and the capillary transport layer 5 is made of capillary foam titanium. The electrolyte 20 is transferred from the electrolyte chamber 2 to the anode chamber through the capillary action of the capillary transport layer 5; an anode catalyst layer 6 is provided on the inner side of the capillary transport layer 5, and the anode catalyst layer 6 is made of iridium dioxide. During the electrolysis process, the electrolyte 20 is transferred to the anode catalyst layer 6 through the capillary transport layer 5, and an oxidation reaction occurs to generate oxygen. In the cathode unit, the cathode plate 10 is made of titanium, and is provided with a cathode plate flow channel 14 and a hydrogen outlet 12. The cathode plate 10 plays the role of conducting electrons and transmitting gas; a cathode gas diffusion layer 9 is provided on the inner side of the cathode plate 10. The cathode gas diffusion layer 9 is made of a hydrophobic titanium mesh material, and the cathode gas diffusion layer 9 plays the role of transmitting hydrogen; a cathode catalyst layer 8 is provided on the inner side of the cathode gas diffusion layer 9. The cathode catalyst layer 8 is made of platinum. During the electrolysis process, protons are transmitted to the cathode catalyst layer 8 through a proton exchange membrane, and a reduction reaction occurs to generate hydrogen.

[0027] An insulating gasket 17 is provided on the side of the anode plate 3 away from the capillary transport layer 5, an anode terminal plate 15 is provided on one side of the insulating gasket 17, and the oxygen outlet 11 penetrates the insulating gasket 17 and the anode terminal plate 15; an insulating gasket 17 is provided on the side of the cathode plate 10 away from the cathode gas diffusion layer 9, a cathode terminal plate 16 is provided on one side of the insulating gasket 17, and the hydrogen outlet 12 penetrates the insulating gasket 17 and the cathode terminal plate 16; the cathode plate 10 is sealed and connected to the cathode gas diffusion layer 9 through a sealing gasket 18. The capillary transport layer 5 is connected to the anode plate 3 through a capillary transport layer sealing gasket 19; the insulating gasket 17 is used for electrical insulation, preventing current short circuit, improving safety, and also plays a certain role in thermal insulation.

[0028] The electrolyte chamber 2 stores an electrolyte 20 which is pure water. The electrolyte 20 is connected to the electrolytic component 1 through the capillary transmission layer 5 and the electrolyte 20 is continuously supplied to the anode chamber through the capillary transmission layer 5 to ensure that the electrolysis reaction continues to occur.

[0029] In a self-priming capillary electrolyzer structure for producing hydrogen by electrolysis of water provided by the present invention, during the process of electrolysis of water, the electrolyte 20 is first transported from the electrolyte chamber 2 to the anode chamber through the capillary action of the capillary transport layer 5, and the power supply is connected to start electrolysis of water. The oxygen generated at the anode during the electrolysis process is discharged through the anode plate flow channel 13 and the oxygen outlet 11, wherein the direction of oxygen generation is perpendicular to the transmission direction of the electrolyte 20, and can be discharged without resistance without generating bubbles. A reduction reaction occurs on the cathode side to generate hydrogen, which is transmitted through the cathode gas diffusion layer 9 and discharged through the cathode plate flow channel 14 and the hydrogen outlet 12. During the entire electrolysis process, no bubbles are generated, which accelerates gas discharge and improves the efficiency of hydrogen production by PEM electrolysis of water, and its hydrogen production efficiency can be increased to 97.3%.

[0030] The method for preparing the capillary transport layer used in the self-absorption water electrolysis hydrogen production capillary electrolyzer structure of this embodiment comprises the following steps: Step 1: Place pure titanium powder with a particle size of less than 74 μm and paraffin wax in a volume ratio of 3:1 into a glass container and heat to 60 o C. Mix well with a stirrer to prepare a slurry.

[0031] Step 2: Immerse the organic foam polyurethane with a porosity of 95%, a pore size of 0.5mm, a through-porosity of 100%, and a thickness of 2mm in the titanium powder slurry. Repeat the immersion several times until the organic foam completely wraps the powder slurry. Leave it at room temperature for 30 minutes until it solidifies.

[0032] Step 3: Place the organic foam wrapped with titanium slurry in a degreasing furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, degreasing temperature 500 o C, keep warm for 4 hours to prepare powder.

[0033] Step 4: Place the powder in a vacuum furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, heated to 1200 o C, and kept warm for 0.5 hours to prepare porous titanium.

[0034] Step 5: Anodize the porous titanium at a constant temperature of 25 o C water bath, with porous titanium as anode and platinum sheet as cathode, a constant voltage of 50V was applied for 10 minutes to prepare a capillary transmission layer.

[0035] The prepared capillary transmission layer has a pore size of 0.8 mm (e.g. Figure 7 ), the porosity is 75% and the through-porosity is 100%.

[0036] Example 2 A self-priming water electrolysis hydrogen production capillary electrolyzer structure, applied to PEM water electrolysis hydrogen production such as Figure 4 As shown, the electrolytic cell comprises an electrolytic component 1 and an electrolyte chamber 2. The electrolyte chamber 2 is located on the upper side of the electrolytic component 1. The components of the electrolytic cell are arranged in order. Figure 4 Assemble.

[0037] In the electrolysis assembly 1, the diaphragm 7 is a proton exchange membrane, and an anode unit is provided on one side of the proton exchange membrane, and a cathode unit is provided on the other side thereof. The anode unit undergoes an oxidation reaction, and the cathode unit undergoes a reduction reaction. In the anode unit, the anode plate 3 is made of titanium, and is provided with an anode plate flow channel 13 and an oxygen outlet 11. The anode plate 3 plays the role of conducting electrons and transmitting gas; a capillary transport layer 5 is provided on the inner side of the anode plate 3, and the capillary transport layer 5 is made of capillary foam titanium. The electrolyte 20 is transferred from the electrolyte chamber 2 to the anode chamber through the capillary action of the capillary transport layer 5; an anode catalyst layer 6 is provided on the inner side of the capillary transport layer 5, and the anode catalyst layer 6 is made of iridium dioxide. During the electrolysis process, the electrolyte 20 is transferred to the anode catalyst layer 6 through the capillary transport layer 5, and an oxidation reaction occurs to generate oxygen. In the cathode unit, the cathode plate 10 is made of titanium, and is provided with a cathode plate flow channel 14 and a hydrogen outlet 12. The cathode plate 10 plays the role of conducting electrons and transmitting gas; a cathode gas diffusion layer 9 is provided on the inner side of the cathode plate 10. The cathode gas diffusion layer 9 is made of a hydrophobic titanium mesh material, and the cathode gas diffusion layer 9 plays the role of transmitting hydrogen; a cathode catalyst layer 8 is provided on the inner side of the cathode gas diffusion layer 9. The cathode catalyst layer 8 is made of platinum. During the electrolysis process, protons are transmitted to the cathode catalyst layer 8 through a proton exchange membrane, and a reduction reaction occurs to generate hydrogen.

[0038] An insulating gasket 17 is provided on the side of the anode plate 3 away from the capillary transport layer 5, an anode terminal plate 15 is provided on one side of the insulating gasket 17, and the oxygen outlet 11 penetrates the insulating gasket 17 and the anode terminal plate 15; an insulating gasket 17 is provided on the side of the cathode plate 10 away from the cathode gas diffusion layer 9, a cathode terminal plate 16 is provided on one side of the insulating gasket 17, and the hydrogen outlet 12 penetrates the insulating gasket 17 and the cathode terminal plate 16, and the cathode plate 10 is sealed and connected with the cathode gas diffusion layer 9 through a sealing gasket 18. The capillary transport layer 5 is connected with the anode plate 3 through a capillary transport layer sealing gasket 19; the insulating gasket 17 is used for electrical insulation, preventing current short circuit, improving safety, and also plays a certain role in thermal insulation.

[0039] The electrolyte chamber 2 stores electrolyte 20, which is pure water. The electrolyte chamber 2 is located on the upper side of the electrolytic component 1, and is connected to the electrolytic component 1 through the capillary transport layer 5, and the electrolyte 20 is continuously supplied to the anode chamber through the capillary transport layer 5. Compared with Example 1, the electrolyte 20 relies on gravity to accelerate the transmission of the electrolyte 20 in the capillary transport layer 5, thereby ensuring that the electrolysis reaction continues to occur.

[0040] In a self-priming capillary electrolyzer structure for producing hydrogen from water by electrolysis provided by the present invention, during the process of electrolyzing water, the electrolyte 20 is first transported from the electrolyte chamber 2 to the anode chamber through the capillary transport layer 5, and the power supply is connected to start electrolyzing water. The oxygen generated at the anode during the electrolysis process is discharged through the anode plate flow channel 13 and the oxygen outlet 11, wherein the direction in which the oxygen is generated is perpendicular to the transmission direction of the electrolyte 20, and can be discharged without resistance without generating bubbles. A reduction reaction occurs on the cathode side to generate hydrogen, which is transmitted through the cathode gas diffusion layer 9 and discharged through the cathode plate flow channel 14 and the hydrogen outlet 12. During the entire electrolysis process, no bubbles are generated, which accelerates gas discharge and improves the efficiency of hydrogen production by PEM water electrolysis, and its hydrogen production efficiency can be increased to 98.6%.

[0041] The method for preparing the capillary transport layer used in the self-absorption water electrolysis hydrogen production capillary electrolyzer structure of this embodiment comprises the following steps: Step 1: Place pure titanium powder with a particle size of less than 74 μm and paraffin wax in a volume ratio of 2:1 into a glass container and heat to 60 o C. Mix well with a stirrer to prepare a slurry.

[0042] Step 2: Immerse the organic foam polyurethane with a porosity of 95%, a pore size of 0.5mm, a through-porosity of 100%, and a thickness of 2mm in the titanium powder slurry. Repeat the immersion several times until the organic foam completely wraps the powder slurry. Leave it at room temperature for 30 minutes until it solidifies.

[0043] Step 3: Place the organic foam wrapped with titanium slurry in a degreasing furnace, fill it with argon gas, and set the degreasing temperature at 500 o C, keep warm for 4 hours to prepare powder.

[0044] Step 4: Place the powder in a vacuum furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, heated to 1200 o C, and kept warm for 0.5 hours to prepare porous titanium.

[0045] Step 5: Anodize the porous titanium at a constant temperature of 25 o In a C water bath, porous titanium was used as the anode and a platinum sheet was used as the cathode. A constant voltage of 50 V was applied for 10 minutes to prepare a capillary transmission layer.

[0046] The prepared capillary transmission layer has a pore size of 0.8 mm, a porosity of 75%, and a through-pore rate of 100%.

[0047] Example 3 A self-priming water electrolysis hydrogen production capillary electrolyzer structure, applied to PEM water electrolysis hydrogen production such as Figure 5 As shown, the electrolytic cell comprises an electrolytic component 1 and an electrolyte chamber 2. The components of the electrolytic cell are arranged in order. Figure 5 Assemble.

[0048] In the electrolysis component 1, the diaphragm 7 adopts a proton exchange membrane, and an anode unit is provided on one side of the proton exchange membrane, and a cathode unit is provided on the other side thereof. The anode unit undergoes an oxidation reaction, and the cathode unit undergoes a reduction reaction. In the anode unit, the anode plate 3 is made of titanium, and is provided with an oxygen outlet 11, and has a flow channel-free design. The anode plate 3 plays the role of conducting electrons; an anode gas diffusion layer 4 is provided on the inner side of the anode plate 3, and the anode gas diffusion layer 4 is made of a hydrophobic titanium mesh material, and the anode gas diffusion layer 4 plays the role of transmitting oxygen; a capillary transmission layer 5 is provided on the inner side of the anode gas diffusion layer 4, and the capillary transmission layer 5 is made of a capillary foam titanium material, and the electrolyte 20 is transmitted from the electrolyte chamber 2 to the anode chamber through the capillary action of the capillary transmission layer 5; an anode catalyst layer 6 is provided on the inner side of the capillary transmission layer 5, and the anode catalyst layer 6 is made of iridium dioxide. During the electrolysis process, the electrolyte 20 is transmitted to the anode catalyst layer 6 through the capillary transmission layer 5, and an oxidation reaction occurs to generate oxygen. In the cathode unit, the cathode plate 10 is made of titanium, has a hydrogen outlet 12, and has a flow channel-free design. The cathode plate 10 plays the role of conducting electrons. A cathode gas diffusion layer 9 is provided on the inner side of the cathode plate 10. The cathode gas diffusion layer 9 is made of carbon felt and plays the role of transmitting hydrogen. A cathode catalyst layer 8 is provided on the inner side of the cathode gas diffusion layer 9. The cathode catalyst layer 8 is made of platinum. During the electrolysis process, protons are transmitted to the cathode catalyst layer 8 through a proton exchange membrane, and a reduction reaction occurs to generate hydrogen.

[0049] An insulating gasket 17 is provided on the side of the anode plate 3 away from the anode gas diffusion layer 4, and an anode terminal plate 15 is provided on one side of the insulating gasket 17. The anode plate 3 and the anode gas diffusion layer 4 are sealed and connected by a sealing gasket 18, and the oxygen outlet 11 passes through the insulating gasket 17 and the anode terminal plate 15; an insulating gasket 17 is provided on the side of the cathode plate 10 away from the cathode gas diffusion layer 9, and a cathode terminal plate 16 is provided on one side of the insulating gasket 17, and the hydrogen outlet 12 passes through the insulating gasket 17 and the cathode terminal plate 16; the cathode plate 10 and the cathode gas diffusion layer 9 are sealed and connected by the sealing gasket 18. The capillary transport layer 5 and the anode gas diffusion layer 4 are connected by a capillary transport layer sealing gasket 19; the insulating gasket 17 is used for electrical insulation, prevents current short circuit, improves safety, and also plays a certain role in thermal insulation.

[0050] The electrolyte chamber 2 stores an electrolyte 20 which is pure water. The electrolyte 20 is connected to the electrolytic component 1 through the capillary transmission layer 5 and the electrolyte 20 is continuously supplied to the anode chamber through the capillary transmission layer 5 to ensure that the electrolysis reaction continues to occur.

[0051] In a self-priming capillary electrolyzer structure for producing hydrogen by electrolysis of water provided by the present invention, during the process of electrolysis of water, the electrolyte 20 is first transported from the electrolyte chamber 2 to the anode chamber through the capillary transmission layer 5, and the power supply is connected to start electrolysis of water. The oxygen generated by the anode during the electrolysis process is transmitted through the anode gas diffusion layer 4 and directly discharged through the oxygen outlet 11, wherein the direction of oxygen generation is perpendicular to the transmission direction of the electrolyte 20, and can be discharged without resistance, without generating bubbles, and a reduction reaction occurs on the cathode side to generate hydrogen, which is transmitted through the cathode gas diffusion layer 9 and directly discharged through the hydrogen outlet 12. During the entire electrolysis process, no bubbles are generated, which accelerates gas discharge and improves the efficiency of PEM water electrolysis to produce hydrogen, and its hydrogen production efficiency can be increased to 96.1%. In addition, the anode and cathode plates are processed without flow channels, which reduces the processing cost of the anode and cathode plates, solves the difficulty of titanium plate flow channel processing, and reduces the cost of the PEM electrolyzer.

[0052] The method for preparing the capillary transport layer used in the self-absorption water electrolysis hydrogen production capillary electrolyzer structure of this embodiment comprises the following steps: Step 1: Place pure titanium powder with a particle size of less than 38 μm and paraffin wax in a volume ratio of 3:1 into a glass container and heat to 60 o C. Mix well with a stirrer to prepare a slurry.

[0053] Step 2: Immerse the organic foam polyurethane with a porosity of 85%, a pore size of 0.4mm, a through-porosity of 100%, and a thickness of 2mm in the titanium powder slurry. Repeat the immersion several times until the organic foam completely wraps the powder slurry. Leave it at room temperature for 30 minutes until it solidifies.

[0054] Step 3: Place the organic foam wrapped with titanium slurry in a degreasing furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, degreasing temperature 700 o C, keep warm for 2 hours to prepare powder.

[0055] Step 4: Place the powder in a vacuum furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, heated to 1000 o C, keep warm for 1 hour to prepare porous titanium.

[0056] Step 5: Anodize the porous titanium at a constant temperature of 25 o C water bath, with porous titanium as anode and platinum sheet as cathode, a constant voltage of 50V was applied for 10 minutes to prepare a capillary transmission layer.

[0057] The prepared capillary transmission layer has a pore size of 0.3 mm, a porosity of 70%, and a through-pore rate of 95%.

[0058] Example 4 A self-priming water electrolysis hydrogen production capillary electrolyzer structure, applied to AEM water electrolysis hydrogen production such as Figure 1 As shown, the electrolytic cell comprises an electrolytic component 1 and an electrolyte chamber 2. The components of the electrolytic cell are arranged in order. Figure 1 Assemble.

[0059] In the electrolytic assembly 1, the diaphragm 7 is an anion exchange membrane, one side of the anion exchange membrane is provided with an anode unit, and the other side thereof is provided with a cathode unit, the anode unit undergoes an oxidation reaction, and the cathode unit undergoes a reduction reaction. In the anode unit, the anode plate 3 is made of stainless steel, and is provided with an anode plate flow channel 13 and an oxygen outlet 11, and the anode plate 3 plays the role of conducting electrons and transmitting gas; a capillary transport layer 5 is provided on the inner side of the anode plate 3, and the capillary transport layer 5 is made of capillary nickel foam material, and the electrolyte 20 is transferred from the electrolyte chamber 2 to the anode chamber through the capillary action of the capillary transport layer 5; an anode catalyst layer 6 is provided on the inner side of the capillary transport layer 5, and the anode catalyst layer 6 is made of nickel-iron alloy. In the cathode unit, the cathode plate 10 is made of stainless steel, and is provided with a cathode plate flow channel 14 and a hydrogen outlet 12. The cathode plate 10 plays the role of conducting electrons and transmitting gas; a cathode gas diffusion layer 9 is provided inside the cathode plate 10, and the cathode gas diffusion layer 9 is made of a hydrophobic titanium mesh material, and the cathode gas diffusion layer 9 plays the role of transmitting hydrogen; a cathode catalyst layer 8 is provided inside the cathode gas diffusion layer 9, and the cathode catalyst layer 8 is made of nickel. During the electrolysis process, the electrolyte 20 is transmitted to the anode chamber through the capillary transmission layer 5, transmitted to the anion exchange membrane through the anode catalyst layer 6, and then penetrated into the cathode catalyst layer 8 through the anion exchange membrane, a reduction reaction occurs, hydrogen and anions are generated, and the anions are transmitted to the anode catalyst layer 6 through the anion exchange membrane, and an oxidation reaction occurs to generate oxygen.

[0060] An insulating gasket 17 is provided on the side of the anode plate 3 away from the capillary transport layer 5, an anode terminal plate 15 is provided on one side of the insulating gasket 17, and the oxygen outlet 11 penetrates the insulating gasket 17 and the anode terminal plate 15; an insulating gasket 17 is provided on the side of the cathode plate 10 away from the cathode gas diffusion layer 9, a cathode terminal plate 16 is provided on one side of the insulating gasket 17, and the hydrogen outlet 12 penetrates the insulating gasket 17 and the cathode terminal plate 16; the cathode plate 10 is sealed and connected to the cathode gas diffusion layer 9 through a sealing gasket 18. The capillary transport layer 5 is connected to the anode plate 3 through a capillary transport layer sealing gasket 19; the insulating gasket 17 is used for electrical insulation, preventing current short circuit, improving safety, and also plays a certain role in thermal insulation.

[0061] The electrolyte chamber 2 stores an electrolyte 20, which is a 5 mol / L potassium hydroxide solution. The electrolyte chamber 2 is connected to the electrolytic component 1 through the capillary transport layer 5, and the electrolyte 20 is continuously supplied to the anode chamber through the capillary transport layer 5 to ensure that the electrolytic reaction continues to occur.

[0062] In a self-priming capillary electrolyzer structure for producing hydrogen by electrolysis of water provided by the present invention, during the process of electrolysis of water, the electrolyte 20 is first transported from the electrolyte chamber 2 to the anode chamber through the capillary transport layer 5, and the power supply is connected to start electrolysis of water. The oxygen generated by the anode during the electrolysis process is discharged through the anode plate flow channel 13 and the oxygen outlet 11, wherein the direction of oxygen generation is perpendicular to the transmission direction of the electrolyte 20, and can be discharged without resistance without generating bubbles. A reduction reaction occurs on the cathode side to generate hydrogen, which is transmitted through the cathode gas diffusion layer 9 and discharged through the cathode plate flow channel 14 and the hydrogen outlet 12. During the entire electrolysis process, no bubbles are generated, which accelerates the gas discharge and improves the efficiency of AEM water electrolysis to produce hydrogen, and its hydrogen production efficiency can be increased to 94.5%.

[0063] The method for preparing the capillary transport layer used in the self-absorption water electrolysis hydrogen production capillary electrolyzer structure of this embodiment comprises the following steps: Step 1: Place pure nickel powder with a particle size of less than 38 μm and paraffin wax in a volume ratio of 3:1 into a glass container and heat to 60 o C. Mix well with a stirrer to prepare a slurry.

[0064] Step 2: Immerse the organic foam polyurethane with a porosity of 85%, a pore size of 0.4mm, a through-porosity of 100%, and a thickness of 2mm in the slurry. Repeat the immersion several times until the organic foam completely wraps the slurry. Leave it at room temperature for 30 minutes until it solidifies.

[0065] Step 3: Place the organic foam wrapped with the slurry in a degreasing furnace under vacuum conditions with a vacuum degree of less than 10 - 3 Pa, degreasing temperature 700 o C, keep warm for 2 hours to prepare powder.

[0066] Step 4: Place the powder in a vacuum furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, heated to 1100 o C, and kept warm for 1 hour to prepare porous nickel.

[0067] Step 5: Plasma-treat the porous nickel under vacuum conditions with a vacuum degree of less than 10 -2 Pa, power 20 watts, plasma treatment for 10 minutes to prepare a capillary transmission layer.

[0068] The prepared capillary transmission layer has a pore size of 0.2 mm, a porosity of 65%, and a through-porosity of 93%.

[0069] Example 5 A self-priming water electrolysis hydrogen production capillary electrolyzer structure, applied to AEM water electrolysis hydrogen production such as Figure 6As shown, the electrolytic cell comprises an electrolytic component 1 and an electrolyte chamber 2. The components of the electrolytic cell are arranged in order. Figure 6 Assemble.

[0070] In the electrolytic assembly 1, the diaphragm 7 is an anion exchange membrane, and an anode unit is provided on one side of the anion exchange membrane, and a cathode unit is provided on the other side thereof. The anode unit undergoes an oxidation reaction, and the cathode unit undergoes a reduction reaction. In the anode unit, the anode plate 3 is made of stainless steel, and is provided with an anode plate flow channel 13 and an oxygen outlet 11. The anode plate 3 plays the role of conducting electrons and transmitting gas; an anode gas diffusion layer 4 is provided inside the anode plate 3, and the anode gas diffusion layer 4 is made of a hydrophobic nickel mesh material, and the anode gas diffusion layer 4 plays the role of transmitting oxygen; an anode catalyst layer 6 is provided inside the anode gas diffusion layer 4, and the anode catalyst layer 6 is made of a nickel-iron alloy material. In the cathode unit, the cathode plate 10 is made of stainless steel, and is provided with a cathode plate flow channel 14 and a hydrogen outlet 12. The cathode plate 10 plays the role of conducting electrons and transmitting gas; a capillary transport layer 5 is provided inside the cathode plate 10, and the capillary transport layer 5 is made of capillary nickel foam. The electrolyte 20 is transferred from the electrolyte chamber 2 to the cathode chamber through the capillary action of the capillary transport layer 5; a cathode catalyst layer 8 is provided inside the capillary transport layer 5, and the cathode catalyst layer 8 is made of nickel. During the electrolysis process, the electrolyte 20 is directly transferred to the cathode chamber through the capillary transport layer 5, and a reduction reaction occurs to generate hydrogen and anions. The anions are transferred to the anode catalyst layer 6 through the anion exchange membrane, and an oxidation reaction occurs to generate oxygen.

[0071] An insulating gasket 17 is provided on the side of the anode plate 3 away from the anode gas diffusion layer 4, an anode terminal plate 15 is provided on one side of the insulating gasket 17, and the oxygen outlet 11 penetrates the insulating gasket 17 and the anode terminal plate 15; the anode plate 3 and the anode gas diffusion layer 4 are sealed and connected by a sealing gasket 18; an insulating gasket 17 is provided on the side of the cathode plate 10 away from the capillary transmission layer 5, a cathode terminal plate 16 is provided on one side of the insulating gasket 17, and the hydrogen outlet 12 penetrates the insulating gasket 17 and the cathode terminal plate 16. The capillary transmission layer 5 and the cathode plate 10 are connected by a capillary transmission layer sealing gasket 19. The insulating gasket 17 is used for electrical insulation, prevents current short circuit, improves safety, and also plays a certain role in thermal insulation.

[0072] The electrolyte chamber 2 stores an electrolyte 20 which is a 1 mol / L potassium hydroxide solution. The electrolyte 20 is connected to the electrolytic component 1 through the capillary transport layer 5, and the electrolyte 20 is continuously supplied to the cathode chamber through the capillary transport layer 5 to ensure that the electrolytic reaction continues to occur.

[0073] In a self-absorption type electrolysis water hydrogen production capillary electrolyzer structure provided by the present invention, in the process of electrolysis of water, firstly, the electrolyte 20 is transported from the electrolyte chamber 2 to the cathode chamber through the capillary transmission layer 5, and the power supply is connected to start electrolysis of water. The oxygen generated by the anode during the electrolysis process is transmitted through the anode gas diffusion layer 4, and discharged through the anode plate flow channel 13 and the oxygen outlet 11, and a reduction reaction occurs on the cathode side to produce hydrogen, which is discharged through the cathode plate flow channel 14 and the hydrogen outlet 12, wherein the direction of hydrogen production is perpendicular to the transmission direction of the electrolyte 20, and can be discharged without resistance without generating bubbles. During the entire electrolysis process, no bubbles are generated, which accelerates the gas discharge and improves the efficiency of AEM electrolysis water hydrogen production. Compared with Example 4, this example directly transmits the electrolyte 20 to the cathode chamber, and a reduction reaction occurs to generate hydrogen, shortening the transmission path of the electrolyte 20, and directly transporting the electrolyte 20 to the reaction zone, and its hydrogen production efficiency can be increased to 98.5%.

[0074] The method for preparing the capillary transport layer used in the self-absorption water electrolysis hydrogen production capillary electrolyzer structure of this embodiment comprises the following steps: Step 1: Place pure nickel powder with a particle size of less than 38 μm and paraffin wax in a volume ratio of 2:1 into a glass container and heat to 60 o C. Mix well with a stirrer to prepare a slurry.

[0075] Step 2: Immerse the organic foam polyurethane with a porosity of 85%, a pore size of 0.4mm, a through-porosity of 100%, and a thickness of 2mm in the nickel powder slurry. Repeat the immersion several times until the organic foam completely wraps the slurry. Place it at room temperature for 30 minutes until it solidifies.

[0076] Step 3: Place the organic foam wrapped with nickel powder in a degreasing furnace, fill it with argon gas, and set the degreasing temperature at 700 o C, keep warm for 2 hours to prepare powder.

[0077] Step 4: Place the powder in a vacuum furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, heated to 1100 o C, and kept warm for 1 hour to prepare porous nickel.

[0078] Step 5: Plasma-treat the porous nickel under vacuum conditions with a vacuum degree of less than 10 -2 Pa, power 20 watts, plasma treatment for 10 minutes to prepare a capillary transmission layer.

[0079] The prepared capillary transmission layer has a pore size of 0.2 mm, a porosity of 65%, and a through-porosity of 93%.

[0080] Example 6 A self-priming water electrolysis hydrogen production capillary electrolyzer structure, applied to AEM water electrolysis hydrogen production such as Figure 5 As shown, the electrolytic cell comprises an electrolytic component 1 and an electrolyte chamber 2. The components of the electrolytic cell are arranged in order. Figure 5 Assemble.

[0081] In the electrolytic assembly 1, the diaphragm 7 is an anion exchange membrane, and an anode unit is provided on one side of the anion exchange membrane, and a cathode unit is provided on the other side thereof, wherein an oxidation reaction occurs in the anode unit and a reduction reaction occurs in the cathode unit. In the anode unit, the anode plate 3 is made of stainless steel, and is provided with an oxygen outlet 11, and has a flow channel-free design, and the anode plate 3 serves to conduct electrons; an anode gas diffusion layer 4 is provided on the inner side of the anode plate 3, and the anode gas diffusion layer 4 is made of a hydrophobic nickel mesh material, and the anode gas diffusion layer 4 serves to transmit oxygen; a capillary transport layer 5 is provided on the inner side of the anode gas diffusion layer 4, and the capillary transport layer 5 is made of a capillary nickel foam material, and the electrolyte 20 is transferred from the electrolyte chamber 2 to the anode chamber through the capillary action of the capillary transport layer 5; an anode catalyst layer 6 is provided on the inner side of the capillary transport layer 5, and the anode catalyst layer 6 is made of a nickel-iron alloy material. In the cathode unit, the cathode plate 10 is made of stainless steel, and is provided with a hydrogen outlet 12, and has a flow channel-free design. The cathode plate 10 plays the role of conducting electrons; a cathode gas diffusion layer 9 is provided inside the cathode plate 10, and the cathode gas diffusion layer 9 is made of a hydrophobic nickel mesh material, and the cathode gas diffusion layer 9 plays the role of transmitting hydrogen; a cathode catalyst layer 8 is provided inside the cathode gas diffusion layer 9, and the cathode catalyst layer 8 is made of nickel. During the electrolysis process, the electrolyte 20 is transmitted to the anode chamber through the capillary transmission layer 5, and is transmitted to the anion exchange membrane through the anode catalyst layer 6, and then penetrates into the cathode catalyst layer 8 through the anion exchange membrane, and a reduction reaction occurs to generate hydrogen and anions. The anions are transmitted to the anode catalyst layer 6 through the anion exchange membrane, and an oxidation reaction occurs to generate oxygen.

[0082] An insulating gasket 17 is provided on the side of the anode plate 3 away from the anode gas diffusion layer 4, and an anode terminal plate 15 is provided on one side of the insulating gasket 17. The anode plate 3 and the anode gas diffusion layer 4 are sealed and connected by a sealing gasket 18, and the oxygen outlet 11 passes through the insulating gasket 17 and the anode terminal plate 15; an insulating gasket 17 is provided on the side of the cathode plate 10 away from the cathode gas diffusion layer 9, and a cathode terminal plate 16 is provided on one side of the insulating gasket 17, and the hydrogen outlet 12 passes through the insulating gasket 17 and the cathode terminal plate 16; the cathode plate 10 and the cathode gas diffusion layer 9 are sealed and connected by the sealing gasket 18. The capillary transport layer 5 and the anode gas diffusion layer 4 are connected by a capillary transport layer sealing gasket 19; the insulating gasket 17 is used for electrical insulation, prevents current short circuit, improves safety, and also plays a certain role in thermal insulation.

[0083] The electrolyte chamber 2 stores an electrolyte 20, which is a 5 mol / L sodium hydroxide solution. The electrolyte chamber 2 is connected to the electrolytic component 1 through the capillary transport layer 5, and the electrolyte 20 is continuously supplied to the anode chamber through the capillary transport layer 5 to ensure that the electrolysis reaction continues to occur.

[0084] In a self-priming capillary electrolyzer structure for producing hydrogen from water by electrolysis provided by the present invention, during the process of water electrolysis, the electrolyte 20 is first transported from the electrolyte chamber 2 to the anode chamber through the capillary transmission layer 5, and the power supply is connected to start water electrolysis. The oxygen generated by the anode during the electrolysis process is transmitted through the anode gas diffusion layer 4 and directly discharged through the oxygen outlet 11, wherein the direction of oxygen generation is perpendicular to the transmission direction of the electrolyte 20, and can be discharged without resistance, without generating bubbles, and a reduction reaction occurs on the cathode side to generate hydrogen, which is transmitted through the cathode gas diffusion layer 9 and directly discharged through the hydrogen outlet 12. During the entire electrolysis process, no bubbles are generated, which accelerates gas discharge and improves the efficiency of AEM water electrolysis for hydrogen production, and its hydrogen production efficiency can be increased to 93.5%. In addition, the anode and cathode plates are processed without flow channels, which reduces the processing cost of the anode and cathode plates, solves the difficulty of plate flow channel processing, and reduces the cost of the AEM electrolyzer.

[0085] The method for preparing the capillary transport layer used in the self-absorption water electrolysis hydrogen production capillary electrolyzer structure of this embodiment comprises the following steps: Step 1: Place pure nickel powder with a particle size of less than 38 μm and paraffin wax in a volume ratio of 3:1 into a glass container and heat to 60 o C. Mix well with a stirrer to prepare a slurry.

[0086] Step 2: Immerse the organic foam polyurethane with a porosity of 90%, a pore size of 0.5mm, a through-porosity of 100%, and a thickness of 2mm in the slurry. Repeat the immersion several times until the organic foam completely wraps the slurry. Leave it at room temperature for 30 minutes until it solidifies.

[0087] Step 3: Place the organic foam wrapped with the slurry in a degreasing furnace under vacuum conditions with a vacuum degree of less than 10 - 3 Pa, degreasing temperature 700 o C, keep warm for 2 hours to prepare powder.

[0088] Step 4: Place the powder in a vacuum furnace under vacuum conditions with a vacuum degree of less than 10 -3 Pa, heated to 1000 o C, keep warm for 2 hours to prepare porous nickel.

[0089] Step 5: Plasma-treat the porous nickel under vacuum conditions with a vacuum degree of less than 10 -2 Pa, power 20 watts, plasma treatment for 10 minutes to prepare a capillary transmission layer.

[0090] The prepared capillary transmission layer has a pore size of 0.3 mm, a porosity of 70%, and a through-pore rate of 95%.

[0091] When the capillary electrolytic cell is used alone, an insulating gasket is arranged on the outer side of the anode plate, an anode terminal plate is arranged on the outer side of the insulating gasket, and an insulating gasket is arranged on the outer side of the cathode plate, and a cathode terminal plate is arranged on the outer side of the insulating gasket; When multiple capillary electrolytic cell units are connected, an insulating gasket is arranged on the outside of the anode plate of the capillary electrolytic cell at one end, and an anode terminal plate is arranged on the outside of the insulating gasket, and an insulating gasket is arranged on the outside of the cathode plate of the capillary electrolytic cell at the other end, and a cathode terminal plate is arranged on the outside of the insulating gasket.

[0092] The binder used in this application is paraffin wax, which has liquid fluidity after being heated and melted, and has a fast solidification speed. Metal powder is added to the melted paraffin wax to form a powder slurry. An organic foam is used as a template and immersed in the powder slurry. The organic foam internal frame is wrapped with a layer of powder slurry, and the powder slurry is quickly solidified at room temperature to replicate the internal frame of the organic foam. After degreasing treatment to completely remove the paraffin wax and the organic foam, the remaining metal powder is sintered to prepare a porous material with the same internal frame as the organic foam. By selecting an organic foam with capillary channels, the capillary transmission layer with capillary channels can be prepared.

[0093] Therefore, the present application provides a self-priming capillary electrolyzer for hydrogen production by water electrolysis, which is applied to hydrogen production by water electrolysis by PEM and hydrogen production by water electrolysis by AEM. The electrolyte is transported from the electrolyte chamber to the electrolysis anode chamber or cathode chamber through a capillary transport layer with capillary phenomenon, and the generated oxygen and hydrogen can be discharged directly without resistance without generating bubbles, thus solving the problem of gas bubbles blocking the porous channels in the prior art.

[0094] In the description of this specification, the description with reference to the terms "an experimental example", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the experimental example or example are included in at least one experimental example or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same experimental example or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more experimental examples or examples in a suitable manner.

[0095] Finally, it should be noted that the above experimental examples are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred experimental examples, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A self-priming capillary electrolyzer for producing hydrogen by electrolyzing water, characterized in that: The capillary electrolytic cell includes an electrolytic component and an electrolyte chamber connected by a capillary transmission layer, the electrolytic component includes a diaphragm, an anode unit arranged on one side of the diaphragm, and a cathode unit arranged on one side of the diaphragm, the electrolyte chamber stores electrolyte, and the capillary transmission layer extends into the electrolyte in the electrolyte chamber, connecting the electrolyte chamber and the electrolytic chamber of the electrolytic component.

2. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 1, characterized in that: When used in PEM water electrolysis to produce hydrogen, the diaphragm is a proton exchange membrane and the electrolyte is pure water; when used in AEM water electrolysis to produce hydrogen, the diaphragm is an anion exchange membrane and the electrolyte is one of potassium hydroxide solution, sodium hydroxide solution and pure water; The anode unit includes an anode plate, a capillary transmission layer arranged inside the anode plate, and an anode catalyst layer arranged inside the capillary transmission layer; the cathode unit includes a cathode plate, a cathode gas diffusion layer arranged inside the cathode plate, and a cathode catalyst layer arranged inside the cathode gas diffusion layer; the anode plate and the capillary transmission layer are sealed and connected through a capillary transmission layer sealing gasket; the cathode plate and the cathode gas diffusion layer are sealed and connected through a sealing gasket; Alternatively, the anode unit includes an anode plate, an anode gas diffusion layer arranged on the inner side of the anode plate, a capillary transport layer arranged on the inner side of the anode gas diffusion layer, and an anode catalyst layer arranged on the inner side of the capillary transport layer; the cathode unit includes a cathode plate, a cathode gas diffusion layer arranged on the inner side of the cathode plate, and a cathode catalyst layer arranged on the inner side of the cathode gas diffusion layer; the anode gas diffusion layer is sealed and connected to the anode plate via a sealing gasket, the capillary transport layer is connected to the anode gas diffusion layer via a capillary transport layer sealing gasket; the cathode plate is sealed and connected to the cathode gas diffusion layer via a sealing gasket.

3. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 1, characterized in that: When applied to AEM electrolysis of water to produce hydrogen, the diaphragm is an anion exchange membrane, and the electrolyte is one of potassium hydroxide solution, sodium hydroxide solution, and pure water; the anode unit includes an anode plate, an anode gas diffusion layer arranged on the inner side of the anode plate, and an anode catalyst layer arranged on the inner side of the anode gas diffusion layer; the cathode unit includes a cathode plate, a capillary gas transmission layer arranged on the inner side of the cathode plate, and a cathode catalyst layer arranged on the inner side of the capillary gas transmission layer; the anode gas diffusion layer is connected to the anode plate through a sealing gasket, and the capillary transmission layer is connected to the cathode plate through a capillary transmission layer gasket.

4. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 2 or 3, characterized in that: A hydrogen outlet is arranged on the cathode plate, and an oxygen outlet is arranged on the anode plate.

5. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 4, characterized in that: Gas flow channels are arranged on both the anode plate and the cathode plate.

6. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 5, characterized in that: When the capillary electrolytic cell is used alone, an insulating gasket is arranged on the outer side of the anode plate, an anode terminal plate is arranged on the outer side of the insulating gasket, and an insulating gasket is arranged on the outer side of the cathode plate, and a cathode terminal plate is arranged on the outer side of the insulating gasket; When multiple capillary electrolytic cell units are connected, an insulating gasket is arranged on the outside of the anode plate of the capillary electrolytic cell at one end, and an anode terminal plate is arranged on the outside of the insulating gasket, and an insulating gasket is arranged on the outside of the cathode plate of the capillary electrolytic cell at the other end, and a cathode terminal plate is arranged on the outside of the insulating gasket.

7. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 6, characterized in that: The electrolyte chamber is located at the top or bottom of the electrolytic assembly; the oxygen outlet penetrates the insulating gasket and the anode end plate; the hydrogen outlet penetrates the insulating gasket and the cathode end plate; The cathode plate and the anode plate are made of one or more of titanium, stainless steel, and graphite; the cathode gas diffusion layer is made of carbon paper, one or more of porous titanium, porous nickel, and porous stainless steel; the catalyst in the cathode catalyst layer is one of platinum, nickel, NiMo, and NiP; the diaphragm is a proton exchange membrane or an anion exchange membrane; the catalyst in the anode catalyst layer is one of iridium dioxide and nickel-iron alloy; the capillary transport layer is one or more of capillary foam titanium, capillary foam nickel, and capillary foam stainless steel.

8. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 7, characterized in that: The preparation method of the capillary transmission layer is as follows: Step 1: Heat and stir the metal powder and the binder to form a slurry; Step 2: soaking the organic foam in the slurry obtained in step 1, repeatedly soaking until the organic foam wraps the slurry, and placing it in the air to solidify; Step 3: placing the solidified organic foam wrapped with the slurry obtained in step 2 in a degreasing furnace, and performing degreasing treatment under vacuum conditions or inert gas protection conditions to remove the organic foam and the binder, thereby obtaining a powder; Step 4: placing the powder in a vacuum furnace and subjecting it to vacuum sintering to obtain a porous material; Step 5: The porous material is surface treated to obtain a porous transmission layer.

9. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 8, characterized in that: In step 1, the metal powder is one of titanium, nickel, and stainless steel, and the particle size of the metal powder is less than 300 μm; the binder is paraffin; the heating temperature is 50-70 o C; The volume ratio of metal powder and binder is: 1:3-3:1; Step 2: the organic foam material is one of polyurethane, polyvinyl chloride and polystyrene, the porosity of the organic foam is between 50% and 99%, the pore size is less than 1 mm, and the through-porosity is 98% to 100%; The degreasing conditions in step 3 are: vacuum degree 10 -2 ~10 -5 Pa or inert gas is argon, degreasing temperature is 200~800 o C, keep warm for 1-8 hours; The sintering conditions in step 4 are: vacuum degree 10 -2 ~10 -5 Pa, sintering temperature is 800~1400 o C, keep warm for 1-4 hours; In the surface treatment of step 5, when the metal powder is titanium, porous titanium is anodized, and when the metal powder is nickel, porous nickel is plasma treated. The conditions for anodizing porous titanium are: the electrolyte contains fluorine electrolyte, the porous titanium anode, the platinum cathode, a constant voltage is applied, and the temperature is 0-50 o C water bath, anodizing treatment for 1-60 minutes; plasma treatment of porous nickel conditions: vacuum degree 10 -2 ~10 -5 Pa, power 10-1000 watts, treatment time 1-30 minutes.

10. A self-priming water electrolysis hydrogen production capillary electrolyzer according to claim 9, characterized in that: The pore size of the capillary transmission layer is less than 1 mm, the porosity is between 30% and 99%, and the through-porosity is 50% to 100%.

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