A two-step method for hydrogen fuel cell and its preparation method

Abstract

The application provides a two-step hydrogen fuel cell, which comprises a closed shell, an electrolyte membrane arranged in the middle of the shell, a hydrogen reaction area and an oxygen reaction area arranged on the two sides of the electrolyte membrane respectively, a hydrogen excitation chamber and a hydrogen reaction chamber in the hydrogen reaction area, and an oxygen excitation chamber and an oxygen reaction chamber in the oxygen reaction area, and ultraviolet excitors arranged in the hydrogen excitation chamber and the oxygen excitation chamber. The application also provides a preparation method of the hydrogen fuel cell, which comprises the steps of catalyst preparation, electrode plate preparation, catalyst coating and cell assembly. The application excites hydrogen by ultraviolet light, so that the electrons of hydrogen atoms can jump or be at a critical point of jumping, thereby improving the reaction activity of hydrogen. In addition, the application does not need to use complex catalysts, so that the overall working stability is stronger, and the service life is improved and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fuel cell technology, in particular to a two-step hydrogen fuel cell and a preparation method thereof. BACKGROUND

[0002] A fuel cell is a power generation device that directly converts the chemical energy of fuel and oxidant into electrical energy through electrochemical reactions. Fuel cells can theoretically operate at a thermal efficiency close to 100%, offering high economic efficiency. Currently, various fuel cells in actual operation have a total conversion efficiency of 45% to 60% due to various technical limitations, and up to 80% or more when considering heat utilization. In addition, fuel cell devices contain few or no moving parts, are reliable in operation, require less maintenance, and are quieter than traditional generator sets. In addition, the isothermal electrochemical method directly converts chemical energy into electrical energy without going through a thermal engine process, and is not limited by the Carnot cycle, thus achieving high energy conversion efficiency, clean and complete reactions, and producing little harmful substances, making it an ideal energy utilization method.

[0003] A fuel cell is a device that directly converts chemical energy into electrical energy, and its working principle is based on electrochemical reactions. The core process includes the following steps: 1. Supply of hydrogen and oxygen: hydrogen enters the anode catalyst layer through the anode current collector, and is oxidized under the action of the catalyst to decompose into positively charged hydrogen ions and negatively charged electrons; oxygen enters the cathode catalyst layer through the cathode current collector. 2. Electrochemical reaction: at the anode, hydrogen molecules are decomposed into hydrogen ions and electrons, hydrogen ions pass through the proton exchange membrane to the cathode, and electrons pass through the external circuit to form a current to supply power to the load; at the cathode, hydrogen ions react with oxygen and electrons to generate water and release heat. At the same time, the unreacted hydrogen gas is discharged from the anode and can be recycled for continued use, and the generated water is discharged together with the unreacted oxygen, which can also be reused after separation, so that only clean water is ultimately discharged.

[0004] Currently, hydrogen fuel cells are limited by the difficulty of hydrogen energy storage and safety issues, and have not yet been widely used, remaining in a continuous process of improvement and development. At present, research and development of hydrogen fuel cells mainly focuses on catalysts, aiming to improve reaction activity through new, highly efficient catalysts while reducing the use of precious metals such as platinum, thereby lowering costs. For example, Chinese invention patent application number 2020106528204 discloses a silicon-doped iron-nitrogen / carbon composite catalyst, its preparation method, and its application. Using mesoporous silica spheres as templates, different types of iron precursors and pyrrole as raw materials, Fe / mSiO2@PPY composite material is obtained through gas-phase polymerization in pyrrole vapor, followed by high-temperature calcination with hydrofluoric acid to obtain Si-doped iron-nitrogen / carbon (Si-FeNx / C). This invention uses Si-doped iron-nitrogen / carbon as the cathode material for fuel cells, constructing a high-performance oxygen reduction catalyst. The Si-doped iron-nitrogen / carbon catalyst prepared in this invention exhibits superior catalytic activity under alkaline conditions compared to commercial Pt / C, and also demonstrates high stability and tolerance to methanol.

[0005] However, fuel cell research and development has reached a bottleneck: the catalytic activity of the catalyst has not seen a breakthrough improvement, making it difficult to further enhance reaction efficiency. Improvements need to be made in another direction to further increase the reaction rate. Furthermore, the use of catalysts with various complex doping structures in current fuel cells also leads to a shorter lifespan of the electrode plates, resulting in high operating costs. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a two-step hydrogen fuel cell and its preparation method, which solves the problems of difficulty in further increasing the reaction degree and high cost in existing technologies.

[0007] In a first aspect, the present invention proposes a two-step hydrogen fuel cell, comprising a closed housing, wherein an electrolyte membrane is disposed in the middle of the housing, and a hydrogen reaction zone and an oxygen reaction zone are respectively disposed on both sides of the electrolyte membrane.

[0008] The hydrogen reaction zone includes a hydrogen excitation chamber and a hydrogen reaction chamber connected in sequence. The hydrogen reaction chamber is adjacent to the electrolyte membrane, and an anode plate is installed inside the hydrogen reaction chamber that is in close contact with the electrolyte membrane. The hydrogen excitation chamber and the hydrogen reaction chamber are respectively provided with a hydrogen inlet pipe and a hydrogen outlet pipe at opposite ends.

[0009] The oxygen reaction zone includes an oxygen activation chamber and an oxygen reaction chamber connected in sequence. The oxygen reaction chamber is adjacent to the electrolyte membrane, and a cathode plate is installed inside the oxygen reaction chamber that is in close contact with the electrolyte membrane. An oxygen inlet pipe and a water outlet pipe are respectively installed at opposite ends of the oxygen activation chamber and the oxygen reaction chamber.

[0010] The anode plate and the cathode plate are arranged side by side and symmetrically relative to the electrolyte membrane;

[0011] The hydrogen excitation chamber and the oxygen excitation chamber are internally provided with ultraviolet light exciters, and the ultraviolet light emitted by the ultraviolet light exciters is uniformly scattered in the internal space of the hydrogen excitation chamber and / or the oxygen excitation chamber.

[0012] Further, the anode plate and the cathode plate are three-dimensional porous structures, and the surfaces of the anode plate and the cathode plate are coated with a catalyst.

[0013] Further, the hydrogen excitation chamber and the oxygen excitation chamber are tubular structures, the ultraviolet light exciters comprise a plurality of ultraviolet lamp tubes, the ultraviolet lamp tubes are arranged on the inner wall of the hydrogen excitation chamber and / or the oxygen excitation chamber around the central axis of the hydrogen excitation chamber and / or the oxygen excitation chamber, and the outer side of the ultraviolet lamp tube is further sleeved with a tubular lampshade.

[0014] Preferably, the wavelength range of the ultraviolet light exciter is 220-360nm, and the power is 90-150W.

[0015] In a second aspect, the application further provides a preparation method of a two-step hydrogen fuel cell, comprising the following steps:

[0016] S1, catalyst preparation: taking an iron source, dissolving in a carbon source and a nitrogen source to obtain a mixed solution, the mass ratio of the iron source to the carbon source and the nitrogen source is 4:11-15:20-27; the mixed solution is input into a vertical tubular furnace, and a protective gas is introduced at the same time, the raw material solution is gasified and thermally decomposed in the high temperature zone of the tubular furnace to form nanoclusters, after the thermal decomposition is completed, the nanoclusters form nitrogen-doped carbon-encapsulated iron nanometer core-shell particle products; the nitrogen-doped carbon-encapsulated iron nanometer core-shell particles are placed in aqua regia solution for pickling, then filtered, washed with water to remove residual aqua regia solution, and then dried to obtain an iron-nitrogen-carbon catalyst;

[0017] The iron source is ferrocene or iron acetylacetone; the carbon source is acetonitrile or formaldehyde, and the nitrogen source is pyrrole or melamine;

[0018] The nanometer metal particles of platinum and tungsten are respectively prepared by chemical reduction method, and the particle size is 5-8nm, wherein the mass percentage of platinum is 28-40%;

[0019] S2, electrode plate preparation: according to the proportion of 25-62% of silicon carbide, 24-37% of diiron trioxide, 2-14% of aluminum oxide, 2-16% of silicon dioxide, 0.6-8% of mineralizer and 5-20% of pore-forming agent, the raw materials are weighed, mixed and stirred uniformly, then 3-10% of the mass of the raw materials is added as a binder, and the powder is prepared by putting it into a powdering machine, then the powder is poured into a mold to press into a plate, and then sintering is carried out in an air or oxygen atmosphere to obtain a porous ceramic structure electrode plate;

[0020] The mineralizer is one of calcium oxide, barium oxide, boron oxide or a mixture of two or more thereof;

[0021] The pore-forming agent is one of starch, polystyrene or polymethyl methacrylate;

[0022] The binder is carboxymethyl cellulose or phenolic resin;

[0023] S3, catalyst coating: grinding the iron-nitrogen-carbon catalyst into powder, adding into the silicone polymer adhesive, mixing well to form a cathode catalyst mixture, adding nano metal particles of platinum and tungsten into the silicone polymer adhesive, mixing well to form an anode catalyst mixture;

[0024] Then the electrode plates are respectively immersed in the cathode catalyst mixture and the anode catalyst mixture, the electrode plates are continuously rotated and soaked for 20-30 min, and then taken out and dried at 220-260℃ for 45-60 min, to obtain the cathode plate and the anode plate respectively;

[0025] S4, battery assembly: installing the gas diffusion layer on the surface of the prepared positive plate and negative plate with catalyst coating, and installing the electrolyte film on the parallel cathode plate and anode plate, keeping the installation interval of the electrolyte film on both sides uniform and the sealing good to prevent gas leakage and short circuit phenomenon, and then setting the hydrogen excitation chamber and the oxygen excitation chamber outside the cathode plate and the anode plate, so that the hydrogen excitation chamber is communicated with the anode plate and the oxygen excitation chamber is communicated with the cathode plate, and the hydrogen excitation chamber and the oxygen excitation chamber are respectively connected to the hydrogen source and the oxygen source, to form a complete hydrogen fuel cell.

[0026] Preferably, in the step S1, the reaction temperature of the tube furnace is 500-1300℃, and the heating rate is 5-15℃ / min.

[0027] Preferably, in the step S1, the heating and stirring are also carried out during the pickling, the heating temperature is 30-90℃, and the stirring time is 2-10h.

[0028] Preferably, in the step S1, the iron-nitrogen-carbon catalyst is heated in a vacuum environment during the drying, the heating temperature is 200-400℃, and the holding time is 10-120min.

[0029] Preferably, in the step S2, the heating rate of the sintering process is 1-3℃ / min, the target temperature of the sintering is 1200-1600℃, and the holding time after reaching the target temperature is 0.5-3h.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] Before hydrogen and oxygen enter the anode and cathode regions of the fuel cell, they first pass through an oxygen excitation chamber and an oxygen reaction chamber. Simultaneously, an ultraviolet light exciter is activated to excite the hydrogen, causing electrons in the hydrogen atoms to transition or reach critical transition points, thereby enhancing the reactivity of the hydrogen. This ensures that hydrogen enters the positive electrode and oxygen enters the negative electrode in an optimal activated state, increasing their participation and reaction efficiency in the electrochemical reaction. This method can further enhance the degree and efficiency of the redox reaction without changing the catalyst, thus increasing the battery's energy output power. Furthermore, this invention eliminates the need for complex catalysts, resulting in greater overall operational stability, increased lifespan, and reduced costs. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.

[0033] Figure 2 This is a schematic diagram of the installation of the ultraviolet lamp tube in the hydrogen excitation chamber according to an embodiment of the present invention.

[0034] In the above figures: 1. Shell; 2. Electrolyte membrane; 3. Hydrogen excitation chamber; 4. Hydrogen reaction chamber; 5. Oxygen excitation chamber; 6. Oxygen reaction chamber; 7. Anode plate; 8. Cathode plate; 9. Ultraviolet exciter; 31. Hydrogen inlet pipe; 32. Ultraviolet lamp tube; 33. Lamp cover; 41. Hydrogen outlet pipe; 51. Oxygen inlet pipe; 61. Water outlet pipe. Detailed Implementation

[0035] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0036] like Figure 1 As shown in the figure, an embodiment of the present invention proposes a two-step hydrogen fuel cell, including a closed shell 1, an electrolyte membrane 2 disposed in the middle of the shell 1, and hydrogen reaction zone and oxygen reaction zone disposed on both sides of the electrolyte membrane 2 respectively.

[0037] The hydrogen reaction zone includes a hydrogen excitation chamber 3 and a hydrogen reaction chamber 4 connected in sequence. The hydrogen reaction chamber 4 is adjacent to the electrolyte membrane 2, and an anode plate 7 is installed inside the hydrogen reaction chamber 4 that is in close contact with the electrolyte membrane 2. The hydrogen excitation chamber 3 and the hydrogen reaction chamber 4 are respectively provided with a hydrogen inlet pipe 31 and a hydrogen outlet pipe 41 at opposite ends.

[0038] The oxygen reaction zone includes an oxygen excitation chamber 5 and an oxygen reaction chamber 6 connected in sequence. The oxygen reaction chamber 6 is adjacent to the electrolyte membrane 2, and a cathode plate 8 is installed inside the oxygen reaction chamber 6 in close contact with the electrolyte membrane 2. An oxygen inlet pipe 51 and a water outlet pipe 61 are respectively installed at opposite ends of the oxygen excitation chamber 5 and the oxygen reaction chamber 6.

[0039] The anode plate 7 and cathode plate 8 are arranged side by side and symmetrical with respect to the electrolyte membrane 2. Additionally, in this embodiment, a gas diffusion layer is provided on one side of the anode plate 7 and cathode plate 8, and an external circuit is connected thereto. Its structure is similar to that of existing conventional fuel cells and will not be described in detail here.

[0040] In this embodiment, ultraviolet (UV) exciters 9 are installed inside the hydrogen excitation chamber 3 and the oxygen excitation chamber 5. The UV light emitted by the UV exciters 9 is uniformly scattered throughout the internal space of the hydrogen excitation chamber 3 and / or the oxygen excitation chamber 5. By exciting the hydrogen gas through the UV exciters 9, the electrons of the hydrogen atoms are allowed to transition or reach the critical point of transition, thereby increasing the reactivity of the hydrogen. Therefore, the hydrogen gas is in an optimal activated state when entering the positive electrode and the oxygen gas when entering the negative electrode, increasing their participation and reaction efficiency in the electrochemical reaction.

[0041] Furthermore, the anode plate 7 and cathode plate 8 have a three-dimensional porous structure, and their surfaces are coated with a catalyst. This structure significantly increases the surface area of ​​the anode plate 7 and cathode plate 8, resulting in a larger contact area between the catalyst and hydrogen and oxygen, thereby improving catalytic efficiency.

[0042] like Figure 2 As shown in the preferred embodiment of the present invention, the hydrogen excitation chamber 3 and the oxygen excitation chamber 5 are tubular structures. The ultraviolet (UV) exciter 9 includes twelve UV lamps 32, which are arranged around the central axis of the hydrogen excitation chamber 3 and / or the oxygen excitation chamber 5 on the inner wall of the hydrogen excitation chamber 3 and / or the oxygen excitation chamber 5. A tubular lamp cover 33 is also fitted around the outside of the UV lamps 32. In this embodiment, the emission wavelength range of the UV exciter 9 is 220-360nm, and the power is 90-150W. The parameters of the UV exciter 9 are adjusted according to the size of the hydrogen excitation chamber 3 and the oxygen excitation chamber 5. By precisely controlling the power and irradiation time of the UV lamps, it is ensured that the hydrogen is in the optimal activation state when it enters the positive electrode, while avoiding over-excitation that leads to energy waste and potential safety issues.

[0043] The two-step hydrogen fuel cell preparation method in this embodiment includes the following steps:

[0044] S1. Catalyst preparation: An iron source is dissolved in a carbon source and a nitrogen source to obtain a mixed solution, wherein the mass ratio of the iron source to the carbon source and the nitrogen source is 4:11:20; the mixed solution is fed into a vertical tube furnace, and a protective gas is introduced at the same time. The raw material solution is vaporized and thermally decomposed in the high-temperature zone of the tube furnace to form nanoclusters. The reaction temperature of the tube furnace is 500℃, and the heating rate is 5℃ / min.

[0045] After thermal decomposition, the nanoclusters form nitrogen-doped carbon-coated iron nanocore-shell particles. The nitrogen-doped carbon-coated iron nanocore-shell particles are placed in aqua regia solution for acid washing, while being heated and stirred at 30°C for 2 hours.

[0046] Then, the mixture was filtered, washed with water to remove the residual aqueous solution, and dried. The iron-nitrogen-carbon catalyst was then heated in a vacuum environment at a temperature of 200°C for 10 minutes to obtain the iron-nitrogen-carbon catalyst.

[0047] In this embodiment, the iron source is ferrocene; the carbon source is acetonitrile; and the nitrogen source is pyrrole.

[0048] Platinum and tungsten nanoparticles with a diameter of 5 nm were prepared by chemical reduction, with platinum accounting for 28% of the total mass.

[0049] S2. Electrode plate preparation: Weigh the raw materials according to the following proportions: silicon carbide 25%, ferric oxide 37%, alumina 14%, silicon dioxide 2%, mineralizer 8%, and pore-forming agent 16%. Mix and stir evenly, then add 3% of the raw material mass of binder. Put the mixture into a powder mill to prepare powder. Powder is poured into a mold and pressed into a plate. Then, it is sintered in an air or oxygen atmosphere at a heating rate of 1℃ / min. The target sintering temperature is 1200℃, and the holding time after reaching the target temperature is 0.5h to obtain a porous ceramic structure electrode plate.

[0050] In this embodiment, the mineralizing agent is calcium oxide. The pore-forming agent is starch. The binder is carboxymethyl cellulose.

[0051] S3. Catalyst Coating: The iron, nitrogen, and carbon catalysts are ground into powder and added to the organosilicon polymer binder. They are then thoroughly mixed to form a cathode catalyst mixture. Platinum and tungsten nanoparticles are added to the organosilicon polymer binder and thoroughly mixed to form an anode catalyst mixture.

[0052] The electrode plates were then immersed in the cathode catalyst mixture and the anode catalyst mixture, respectively. The electrode plates were rotated and immersed for 20 minutes. They were then removed and dried at 220°C for 45 minutes to obtain cathode plate 8 and anode plate 7, respectively.

[0053] S4. Battery Assembly: A gas diffusion layer is installed on the prepared positive and negative electrode plates with catalyst coating. At the same time, an electrolyte membrane 2 is installed on the parallel cathode plate 8 and anode plate 7. The installation spacing on both sides of the electrolyte membrane 2 is kept uniform and well sealed to prevent gas leakage and short circuit. Then, a hydrogen excitation chamber 3 and an oxygen excitation chamber 5 are set on the outside of the cathode plate 8 and anode plate 7, so that the hydrogen excitation chamber 3 is connected to the anode plate 7 and the oxygen excitation chamber 5 is connected to the cathode plate 8. The hydrogen excitation chamber 3 and the oxygen excitation chamber 5 are respectively connected to the hydrogen source and the oxygen source to form a complete hydrogen fuel cell.

[0054] Example 2:

[0055] The rest of this embodiment is the same as in Embodiment 1, except that the two-step hydrogen fuel cell preparation method in this embodiment includes the following steps:

[0056] S1. Catalyst preparation: An iron source is dissolved in a carbon source and a nitrogen source to obtain a mixed solution, wherein the mass ratio of the iron source to the carbon source and the nitrogen source is 4:15:27; the mixed solution is fed into a vertical tube furnace, and a protective gas is introduced at the same time. The raw material solution is vaporized and thermally decomposed in the high-temperature zone of the tube furnace to form nanoclusters. The reaction temperature of the tube furnace is 1300℃, and the heating rate is 15℃ / min.

[0057] After thermal decomposition, the nanoclusters form nitrogen-doped carbon-coated iron nanocore-shell particles. The nitrogen-doped carbon-coated iron nanocore-shell particles are placed in aqua regia solution for acid washing, while being heated and stirred at 90°C for 10 hours.

[0058] Then, the mixture was filtered, washed with water to remove the residual aqueous solution, and dried. The iron-nitrogen-carbon catalyst was then heated in a vacuum environment at a temperature of 400°C for 120 minutes to obtain the iron-nitrogen-carbon catalyst.

[0059] In this embodiment, the iron source is iron acetylacetone; the carbon source is formaldehyde; and the nitrogen source is melamine.

[0060] Platinum and tungsten nanoparticles with a diameter of 8 nm were prepared by chemical reduction, with platinum accounting for 40% of the total mass.

[0061] S2. Electrode plate preparation: Weigh the raw materials according to the following proportions: 62% silicon carbide, 24% ferric oxide, 2% alumina, 5% silicon dioxide, 2% mineralizer, and 5% pore-forming agent. Mix and stir evenly, then add 10% of the raw material mass of binder. Put the mixture into a powder mill to prepare powder. Powder is poured into a mold and pressed into a plate. Then, it is sintered in an air or oxygen atmosphere at a heating rate of 3℃ / min. The target sintering temperature is 1600℃, and the holding time after reaching the target temperature is 3h to obtain a porous ceramic structure electrode plate.

[0062] In this embodiment, the mineralizing agent is a mixture of calcium oxide and barium oxide in equal proportions. The pore-forming agent is polystyrene. The binder is phenolic resin.

[0063] S3. Catalyst Coating: The iron, nitrogen, and carbon catalysts are ground into powder and added to the organosilicon polymer binder. They are then thoroughly mixed to form a cathode catalyst mixture. Platinum and tungsten nanoparticles are added to the organosilicon polymer binder and thoroughly mixed to form an anode catalyst mixture.

[0064] The electrode plates were then immersed in the cathode catalyst mixture and the anode catalyst mixture, respectively. The electrode plates were rotated continuously and immersed for 30 minutes. They were then removed and dried at 260°C for 60 minutes to obtain cathode plate 8 and anode plate 7, respectively.

[0065] S4. Battery Assembly: A gas diffusion layer is installed on the prepared positive and negative electrode plates with catalyst coating. At the same time, an electrolyte membrane 2 is installed on the parallel cathode plate 8 and anode plate 7. The installation spacing on both sides of the electrolyte membrane 2 is kept uniform and well sealed to prevent gas leakage and short circuit. Then, a hydrogen excitation chamber 3 and an oxygen excitation chamber 5 are set on the outside of the cathode plate 8 and anode plate 7, so that the hydrogen excitation chamber 3 is connected to the anode plate 7 and the oxygen excitation chamber 5 is connected to the cathode plate 8. The hydrogen excitation chamber 3 and the oxygen excitation chamber 5 are respectively connected to the hydrogen source and the oxygen source to form a complete hydrogen fuel cell.

[0066] Example 3:

[0067] The rest of this embodiment is the same as in Embodiment 1, except that the two-step hydrogen fuel cell preparation method in this embodiment includes the following steps:

[0068] S1. Catalyst preparation: An iron source is dissolved in a carbon source and a nitrogen source to obtain a mixed solution, wherein the mass ratio of the iron source to the carbon source and the nitrogen source is 4:13:24; the mixed solution is fed into a vertical tube furnace, and a protective gas is introduced at the same time. The raw material solution is vaporized and thermally decomposed in the high-temperature zone of the tube furnace to form nanoclusters. The reaction temperature of the tube furnace is 900℃, and the heating rate is 10℃ / min.

[0069] After thermal decomposition, the nanoclusters form nitrogen-doped carbon-coated iron nanocore-shell particles. The nitrogen-doped carbon-coated iron nanocore-shell particles are placed in aqua regia solution for acid washing, while being heated and stirred at 60°C for 6 hours.

[0070] Then, the mixture was filtered, washed with water to remove the residual king solution, and dried. The iron-nitrogen-carbon catalyst was then heated in a vacuum environment at 300°C for 65 minutes to obtain the iron-nitrogen-carbon catalyst.

[0071] In this embodiment, the iron source is ferrocene; the carbon source is acetonitrile; and the nitrogen source is melamine.

[0072] Platinum and tungsten nanoparticles with a diameter of 12.5 nm were prepared by chemical reduction, with platinum accounting for 54% of the total mass.

[0073] S2. Electrode plate preparation: Weigh the raw materials according to the following proportions: silicon carbide 25.4%, ferric oxide 24%, alumina 14%, silicon dioxide 16%, mineralizer 0.6%, and pore-forming agent 20%. Mix and stir evenly, then add 6.5% of the raw material mass of binder. Put the mixture into a powder mill to prepare powder. Powder is poured into a mold and pressed into a plate. Then, it is sintered in an air or oxygen atmosphere at a heating rate of 2℃ / min. The target sintering temperature is 1400℃, and the holding time after reaching the target temperature is 2.5h to obtain a porous ceramic structure electrode plate.

[0074] In this embodiment, the mineralizing agent is a mixture of calcium oxide, barium oxide, and boron oxide in equal proportions. The pore-forming agent is polymethyl methacrylate. The binder is carboxymethyl cellulose.

[0075] S3. Catalyst Coating: The iron, nitrogen, and carbon catalysts are ground into powder and added to the organosilicon polymer binder. They are then thoroughly mixed to form a cathode catalyst mixture. Platinum and tungsten nanoparticles are added to the organosilicon polymer binder and thoroughly mixed to form an anode catalyst mixture.

[0076] The electrode plates were then immersed in the cathode catalyst mixture and the anode catalyst mixture, respectively. The electrode plates were rotated continuously and immersed for 25 minutes. They were then removed and dried at 240°C for 52 minutes to obtain cathode plate 8 and anode plate 7, respectively.

[0077] S4. Battery Assembly: A gas diffusion layer is installed on the prepared positive and negative electrode plates with catalyst coating. At the same time, an electrolyte membrane 2 is installed on the parallel cathode plate 8 and anode plate 7. The installation spacing on both sides of the electrolyte membrane 2 is kept uniform and well sealed to prevent gas leakage and short circuit. Then, a hydrogen excitation chamber 3 and an oxygen excitation chamber 5 are set on the outside of the cathode plate 8 and anode plate 7, so that the hydrogen excitation chamber 3 is connected to the anode plate 7 and the oxygen excitation chamber 5 is connected to the cathode plate 8. The hydrogen excitation chamber 3 and the oxygen excitation chamber 5 are respectively connected to the hydrogen source and the oxygen source to form a complete hydrogen fuel cell.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A two-step hydrogen fuel cell, characterized in that: It includes a closed shell, in which an electrolyte membrane is provided in the middle, and hydrogen reaction zone and oxygen reaction zone are respectively provided on both sides of the electrolyte membrane; The hydrogen reaction zone includes a hydrogen excitation chamber and a hydrogen reaction chamber connected in sequence. The hydrogen reaction chamber is adjacent to the electrolyte membrane, and an anode plate is installed inside the hydrogen reaction chamber that is in close contact with the electrolyte membrane. The hydrogen excitation chamber and the hydrogen reaction chamber are respectively provided with a hydrogen inlet pipe and a hydrogen outlet pipe at opposite ends. The oxygen reaction zone includes an oxygen activation chamber and an oxygen reaction chamber connected in sequence. The oxygen reaction chamber is adjacent to the electrolyte membrane, and a cathode plate is installed inside the oxygen reaction chamber that is in close contact with the electrolyte membrane. An oxygen inlet pipe and a water outlet pipe are respectively installed at opposite ends of the oxygen activation chamber and the oxygen reaction chamber. The anode plate and cathode plate are arranged side by side and symmetrical with respect to the electrolyte membrane; The hydrogen excitation chamber and the oxygen excitation chamber are equipped with ultraviolet light exciters. The ultraviolet light emitted by the ultraviolet light exciters is uniformly scattered in the internal space of the hydrogen excitation chamber and the oxygen excitation chamber, allowing the electrons of hydrogen atoms to jump or be at the critical point of jump, so that hydrogen enters the positive electrode plate and oxygen enters the negative electrode plate in the optimal activation state, thereby improving their participation and reaction efficiency in the electrochemical reaction. The ultraviolet exciter has an emission wavelength range of 220-360nm and a power of 90-150W.

2. The two-step hydrogen fuel cell as described in claim 1, characterized in that: The anode plate and cathode plate have a three-dimensional porous structure, and the surfaces of the anode plate and cathode plate are coated with a catalyst.

3. A two-step hydrogen fuel cell as described in claim 1, characterized in that: The hydrogen excitation chamber and the oxygen excitation chamber are tubular structures. The ultraviolet exciter includes several ultraviolet lamps. The ultraviolet lamps are arranged around the central axis of the hydrogen excitation chamber and / or the oxygen excitation chamber on the inner wall of the hydrogen excitation chamber and / or the oxygen excitation chamber. A tubular lamp cover is also fitted on the outside of the ultraviolet lamps.

4. A method for preparing a two-step hydrogen fuel cell as described in claim 1, characterized in that, Includes the following steps: S1. Catalyst Preparation: An iron source is dissolved in a carbon source and a nitrogen source to obtain a mixed solution, wherein the mass ratio of the iron source to the carbon source and the nitrogen source is 4:11-15:20-27; the mixed solution is fed into a vertical tube furnace, and a protective gas is introduced simultaneously. The raw material solution is vaporized and thermally decomposed in the high-temperature zone of the tube furnace to form nanoclusters. After thermal decomposition, the nanoclusters form nitrogen-doped carbon-coated iron nanocore-shell particles; the nitrogen-doped carbon-coated iron nanocore-shell particles are placed in an aqua regia solution for acid washing, then filtered, washed with water to remove residual aqua regia solution, and then dried to obtain an iron-nitrogen-carbon catalyst; The iron source is ferrocene or ferric acetylacetonate; the carbon source is acetonitrile or formaldehyde; and the nitrogen source is pyrrole or melamine. Platinum and tungsten nanoparticles with a particle size of 5-8 nm were prepared by chemical reduction, with platinum accounting for 28-40% of the total mass. S2. Electrode plate preparation: Weigh the raw materials according to the following proportions: silicon carbide 25-62%, ferric oxide 24-37%, alumina 2-14%, silicon dioxide 2-16%, mineralizer 0.6-8%, and pore-forming agent 5-20%. Mix and stir evenly, then add 3-10% of the raw material mass of binder. Put the mixture into a powder mill to prepare powder. Powder is poured into a mold and pressed into a plate. Then, it is sintered in air or oxygen atmosphere to obtain a porous ceramic structure electrode plate. The mineralizing agent is one or a mixture of two or more of calcium oxide, barium oxide, and boron oxide; The pore-forming agent is one of starch, polystyrene, or polymethyl methacrylate; The adhesive is carboxymethyl cellulose or phenolic resin; S3. Catalyst Coating: The iron, nitrogen, and carbon catalysts are ground into powder and added to the organosilicon polymer binder. They are then thoroughly mixed to form a cathode catalyst mixture. Platinum and tungsten nano-metal particles are added to the organosilicon polymer binder and thoroughly mixed to form an anode catalyst mixture. Then, the electrode plates were immersed in the cathode catalyst mixture and the anode catalyst mixture, respectively. The electrode plates were rotated continuously and immersed for 20-30 minutes. They were then removed and dried at 220-260℃ for 45-60 minutes to obtain the cathode plate and the anode plate, respectively. S4. Battery Assembly: A gas diffusion layer is installed on the prepared positive and negative electrode plates with catalyst coating. At the same time, an electrolyte membrane is installed on the parallel cathode and anode plates, keeping the installation spacing on both sides of the electrolyte membrane uniform and well sealed to prevent gas leakage and short circuit. Subsequently, a hydrogen excitation chamber and an oxygen excitation chamber are set on the outside of the cathode and anode plates, so that the hydrogen excitation chamber is connected to the anode plate and the oxygen excitation chamber is connected to the cathode plate. The hydrogen excitation chamber and the oxygen excitation chamber are respectively connected to the hydrogen source and the oxygen source to form a complete hydrogen fuel cell.

5. The two-step hydrogen fuel cell preparation method as described in claim 4, characterized in that: In step S1, the reaction temperature of the tube furnace is 500-1300℃, and the heating rate is 5-15℃ / min.

6. The two-step method for preparing a hydrogen fuel cell as described in claim 4, characterized in that: In step S1, during pickling, heating and stirring are also performed. The heating temperature is 30-90℃, and the stirring time is 2-10h.

7. The two-step method for preparing a hydrogen fuel cell as described in claim 4, characterized in that: In step S1, during drying, the iron-nitrogen-carbon catalyst is heated in a vacuum environment at a temperature of 200-400℃ for 10-120 minutes.

8. The two-step method for preparing a hydrogen fuel cell as described in claim 4, characterized in that: In step S2, the heating rate of the sintering process is 1-3℃ / min, the target sintering temperature is 1200-1600℃, and the holding time after reaching the target temperature is 0.5-3h.

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