Super-durable solar-driven seawater electrolysis hydrogen production device and hydrogen production method

Abstract

The invention relates to a super-durable solar-driven seawater electrolysis hydrogen production device and a hydrogen production method, and belongs to the technical field of new energy seawater desalination, a solar evaporator is an evaporator with a three-dimensional bionic microstructure at the upper part and a micro-channel at the lower part, the three-dimensional bionic microstructure has super hydrophilicity, the bottom interface of the micro-channel has hydrophilicity, and the micro-channel has super-hydrophilicity. Water flowing out of the micro-channel diffuses along the three-dimensional bionic microstructure due to the super-hydrophilicity; and the electrolytic hydrogen production system comprises an electrolytic tank, a cathode copper plate, a flow guide hopper, a gas collecting pipe and a thin film with a Janus structure. The method comprises the following steps: assembling a hydrogen production device; a temperature gradient is formed in the water film through photo-thermal conversion of solar energy, the Malangei effect is formed, salt crystallization is prevented through brine microcirculation of the Malangei effect, and fresh water is collected; and the power supply system supplies electric energy to the cathode copper plate and the anode graphite plate to perform electrolytic reaction of water. The durability of the device is remarkably improved, and the service life of the device is remarkably prolonged.

Description

Technical Field

[0001] The present invention relates to a seawater evaporation hydrogen production device and method, and in particular to an ultra-durable solar-driven seawater electrolysis hydrogen production device and method, belonging to the technical field of new energy seawater desalination. Background Art

[0002] As the most abundant water resource on earth, seawater has great potential in combination with electrolysis to produce hydrogen. - Extreme corrosion of the anode and Mg 2+ and Ca 2+ The reaction at the cathode produces solid matter, and the ions in seawater hinder the direct electrolysis of seawater, thereby reducing the electrolysis efficiency; in addition, traditional seawater desalination consumes fossil fuels and emits large amounts of carbon dioxide, threatening human survival.

[0003] Solar-powered desalination of seawater for hydrogen production by electrolysis has attracted attention in recent years. However, traditional solar evaporation technology is susceptible to problems such as salt crystallization and corrosion under high salt concentrations, which greatly affects the service life and performance of the equipment.

[0004] Therefore, how to improve the above problems has become a task that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, the present invention provides an ultra-durable solar-driven seawater electrolysis hydrogen production device and a hydrogen production method. The device has a reasonable structure and has the characteristics of efficient hydrogen production and salt resistance.

[0006] In order to solve the problem of high salt concentration and strong corrosiveness in seawater, the evaporator in the device adopts a structure with a three-dimensional bionic microstructure and a microchannel at the bottom, which makes it have Janus characteristics and can operate stably for a long time in the harsh marine environment during the salt water evaporation process;

[0007] To address the problem of low hydrogen production efficiency, the device uses a Janus-structured membrane and electrode integrated structure to achieve rapid unidirectional transport of hydrogen bubbles.

[0008] In view of the above: This application provides the following solutions:

[0009] An ultra-durable solar-driven seawater electrolysis hydrogen production device comprises:

[0010] A seawater evaporation fresh water collection system is used to recover fresh water and feed it into an electrolytic hydrogen production system. The seawater evaporation fresh water collection system comprises a connected solar evaporator, an open container, a fresh water collection container and a transparent cover; the solar evaporator, the open container and the transparent cover enclose an evaporation space;

[0011] Electrolysis hydrogen production system, used for water electrolysis to produce hydrogen;

[0012] A power supply system, used to provide electrical energy to the electrolysis hydrogen production system;

[0013] The solar evaporator is an evaporator having a three-dimensional bionic microstructure on the upper part and a microchannel on the lower part, wherein the three-dimensional bionic microstructure has superhydrophilicity, and the bottom interface of the microchannel has hydrophilicity, and the superhydrophilicity enables water flowing out of the microchannel to diffuse along the three-dimensional bionic microstructure;

[0014] The electrolytic hydrogen production system comprises an electrolytic cell, a cathode copper plate, a flow guide hopper, a gas collecting pipe and a film with a Janus structure, wherein the film can produce a layer of air film when immersed in water; the electrolytic cell is suitable for placing an electrolyte; the anode plate is placed in the electrolytic cell, the cathode copper plate is laid flat on the bottom of the electrolytic cell, the film is arranged on the upper surface of the cathode copper plate and there is a gap between the two, the gap allows hydrogen bubbles to be generated on the surface of the cathode copper plate during electrolysis, the film has an air channel, the flow guide hopper is arranged above the film, the flow guide hopper inlet covers the film, the flow guide hopper outlet is arranged in the inverted gas collecting pipe inlet, the gas collecting pipe is suitable for being filled with water for collecting hydrogen, and the anode graphite plate and the cathode copper plate are electrically connected to the positive and negative electrodes of the power supply system accordingly.

[0015] Furthermore, the solar evaporator is obtained by the following method: firstly, the evaporator is modeled by using SolidWorks software to obtain a 3D model, then the 3D model is saved in STL format, the STL file of the 3D model is imported into a slicing software for slicing and a 2D sliced ​​model image is obtained, and the image is imported into a light-curing 3D printer; at the same time, carbon nanotubes and photosensitive resins with a mass ratio of 1:100 are selected, the prepared carbon nanotubes and photosensitive resins are poured into a container and stirred until they are evenly mixed, and after the stirring is completed, the mixed material is poured into the printing tank of the light-curing 3D printer for printing;

[0016] The printed evaporation device is removed from the printing platform and ultrasonically cleaned with a 95% ethanol solution. After cleaning, the evaporation device is taken out and the ethanol solution on the surface of the evaporation device is blown off with a nitrogen pump. This is repeated several times until there is no residual ethanol solution and resin on the surface of the evaporation device. After that, it is vacuum dried to remove all moisture. After drying, the upper part of the evaporator is treated with an oxygen plasma method to make the upper surface super hydrophilic. The evaporation device is then left to stand until room temperature to obtain a solar evaporator with salt resistance in saturated brine.

[0017] With such a design, the solar evaporator obtained above has Janus characteristics, which improves the evaporation efficiency while preventing salt crystallization when the device works in a harsh seawater environment with high salt concentration, significantly improving the durability of the device and increasing its service life.

[0018] An ultra-durable solar-driven seawater electrolysis hydrogen production method is implemented based on the solar-driven seawater electrolysis hydrogen production device, and the hydrogen production method comprises the following steps:

[0019] S1, placing seawater in the open container, placing the solar evaporator in the open container filled with seawater, floating the solar evaporator on the water, and covering it with a transparent cover;

[0020] S2. The light source is directed to the solar evaporator, the seawater evaporates, and the salt water is transported upward along the microchannel. Under the action of Laplace pressure, a thin water film is formed on the surface of the three-dimensional bionic microstructure. The photothermal conversion of solar energy forms a temperature gradient inside the water film and forms a Marangoni effect. The salt water microcirculation of the Marangoni effect prevents the crystallization of salt.

[0021] S3, the glass cover condenses the generated water vapor into droplets, and the droplets flow into the fresh water collection container under the action of gravity, and the collected fresh water flows into the electrolytic cell through the pipeline;

[0022] S4. The power supply system supplies electricity to the cathode copper plate and the anode plate to perform water electrolysis. During the electrolysis process, the air film generated by the film with the janus structure allows the hydrogen bubbles generated by the electrolysis to be quickly transported in one direction after passing through the airway. Under the action of the hydrophobic layer, the hydrogen bubbles are caused to gather above the hydrophobic layer. When they gather to a certain volume, the bubbles float upward, and under the diversion action of the diversion bucket, the hydrogen is collected in the gas collecting pipe.

[0023] Furthermore, the substrate of the film with the janus structure is a mesh plate, the upper surface of the mesh plate is coated with a hydrophobic layer, and the hydrophobic layer can form an air film when immersed in water.

[0024] Preferably, the hydrophobic layer is made of nano-scale silica particles, which function to reduce the surface tension of the coating. When the film with a Janus structure is immersed in water, the super-hydrophobic treated silica particles form a smooth air film, which has Janus characteristics and has the function of rapid unidirectional transport of hydrogen bubbles.

[0025] Furthermore, the fresh water collection container and the open container are made by fused deposition modeling 3D printing, which is simple in structure and low in cost.

[0026] Furthermore, the solar evaporator is made by photocuring 3D printing, and the grid plate is made by photocuring 3D printing. Such production method improves product accuracy and printing speed.

[0027] The beneficial effects of the present application are as follows: the present application uses solar energy to drive seawater electrolysis to produce hydrogen, and completely relies on renewable solar energy as energy, which not only reduces dependence on traditional power grids, but also avoids the use of fossil energy, thereby effectively reducing carbon emissions. In response to the problems of strong salinity and corrosiveness in the marine environment, the evaporation device in the device of the present invention adopts a solar evaporator with microstructure and microchannel. The 3D micro-nano structure of the evaporator is super-hydrophilic, and the bottom interface of the microchannel is hydrophilic, showing Janus characteristics, which can prevent salt crystallization when the device is working in a harsh seawater environment with high salt concentration, and significantly improves the durability and service life of the device. Compared with traditional freshwater electrolysis hydrogen production technology, the present invention uses seawater as raw material, makes full use of seawater resources widely distributed around the world, solves the problem of freshwater resource shortage, reduces the water source cost in the hydrogen production process, and improves the sustainability and economy of production.

[0028] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation modes of the present invention are described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the ultra-durable solar-driven seawater electrolysis hydrogen production device of this application;

[0030] Figure 2 This is a main cross-sectional view of the seawater evaporation fresh water collection system of the present application;

[0031] Figure 3 An electron microscope image of a 3D bionic solar evaporator in an embodiment;

[0032] Figure 4 is a main cross-sectional view of the electrolysis hydrogen production system in the embodiment;

[0033] Figure 5 is a top view of a film having a Janus structure in an embodiment;

[0034] Figure 6 A diagram showing the structure and arrangement relationship of the cathode copper plate and the thin film with a Janus structure in the embodiment;

[0035] Figure 7 This is a salt resistance test diagram of the solar evaporator of the present application in the embodiment;

[0036] Figure 8 It is a curve diagram of the fresh water collection rate in an outdoor test using the device of the present application in the embodiment;

[0037] Fig. 9 This is a graph showing the relationship between the collected hydrogen and time when the device of the present application is working outdoors in the embodiment;

[0038] Fig.10 This is a stability test diagram of the ultra-durable solar-driven seawater electrolysis hydrogen production device of the present application in the embodiment. DETAILED DESCRIPTION

[0039] Unless otherwise specified, the technical terms or scientific terms used in this embodiment have the common meanings understood by technicians in the field to which this application belongs.

[0040] Reference Figure 1-Figure 3 , an ultra-durable solar-driven seawater electrolysis hydrogen production device comprising:

[0041] The seawater evaporation fresh water collection system 1 is used to recover fresh water and replenish it into the electrolytic hydrogen production system 2, such as Figure 2 As shown, the seawater evaporation freshwater collection system 1 comprises a connected solar evaporator 11, an open container 12, a freshwater collection container 13 and a transparent cover 14; the solar evaporator 11, the open container 12 and the transparent cover 14 enclose an evaporation space;

[0042] Electrolysis hydrogen production system 2, used for water electrolysis to produce hydrogen;

[0043] A power supply system 3, used to provide electric energy to the electrolysis hydrogen production system 2;

[0044] like Figure 3 As shown, the solar evaporator 11 is an evaporator having a three-dimensional bionic microstructure on the upper part and a microchannel (such as a capillary channel) on the lower part, the three-dimensional bionic microstructure has superhydrophilicity, and the bottom interface of the microchannel has hydrophilicity, and the superhydrophilicity makes the water flowing out of the microchannel spread and diffuse along the three-dimensional bionic microstructure;

[0045] Figure 4-Figure 6An electrolytic hydrogen production system is shown, the electrolytic hydrogen production system 2 comprises an electrolytic cell 21, a cathode copper plate 22, a flow guide hopper 23, a gas collecting pipe 24 and a film 25 with a Janus structure, wherein the film 25 can produce a layer of air film when immersed in water; the electrolytic cell 21 is suitable for placing electrolyte; the anode plate 26 is placed in the electrolytic cell 21, the cathode copper plate 22 is laid flat on the bottom of the electrolytic cell 21, and the film 25 is arranged on the upper surface of the cathode copper plate 22 and there is a gap between the two , the gap allows hydrogen bubbles to be generated on the surface of the cathode copper plate 22 during electrolysis, the film 25 has an air channel 251, the guide hopper 23 is arranged above the film 25, the inlet of the guide hopper 23 covers the film 25, the outlet of the guide hopper 23 is arranged in the inlet of the inverted gas collecting pipe 24, the gas collecting pipe 24 is suitable for being filled with water to collect hydrogen, the anode graphite plate 26 and the cathode copper plate 22 are electrically connected to the positive and negative electrodes of the power supply system 3. The air film is distributed on the top of the grid plate and forms a gas channel with the side wall of the grid plate, the purpose of which is to capture, adsorb and transport the bubbles expanding below.

[0046] The device of the present invention has a reasonable structure and has the advantages of high evaporation rate and efficient hydrogen production. In order to solve the problems of high salt concentration and strong corrosiveness in seawater, the evaporation device in the device adopts a solar evaporator with microstructure and microchannel. The 3D micro-nano structure of the evaporator is super hydrophilic, and the bottom interface of the microchannel is hydrophilic, showing Janus characteristics, so that it can operate stably for a long time in a harsh marine environment and has excellent salt resistance.

[0047] Figure 7 The salt resistance test of the solar evaporator of the present application is demonstrated. 50 ml of water is added to three beakers with a capacity of 100 ml, and 5.56 g, 8.82 g and 17.57 g of NaCl are added to the three beakers respectively. After sufficient stirring, 10 wt%, 15 wt% and 26 wt% of salt water are obtained. The salt water is poured into a petri dish, and then the above-mentioned 3D bionic solar evaporator developed by the present application is placed in the 10 wt%, 15 wt% and 26 wt% salt water for 8 hours, and the light intensity is 1000 Wm -2 Then, the common solar evaporator was placed in 10wt%, 15wt% and 26wt% brine respectively for evaporation for 8 hours under the same light intensity (when indoors, the light source can be a simulated daylight xenon lamp to provide solar energy, and when outdoors, direct solar radiation is used). Figure 7 It can be seen that there are a large number of salt crystals on the surface of ordinary evaporators, while the 3D bionic solar evaporator of the present application can evaporate for a long time in high-concentration salt water without salt crystallization, demonstrating super durability and super salt resistance.

[0048] In order to verify that the device of the present invention has the ability to efficiently desalinate seawater and collect fresh water by condensation, the inventor conducted an outdoor test of collecting fresh water by evaporation. The salt water concentration used in the test was 3.5wt% (the world average seawater concentration). Figure 8 As shown, the device in this application can collect up to 0.58Lm in one hour outdoors -2 of fresh water, the lowest is 0.44Lm -2 .

[0049] Based on the above implementation, the following examples are given to express the detailed parts and connection relationships of the device.

[0050] Embodiment 1: The fresh water collection container 13 is in the shape of a truncated cone, and the cross-sectional area of ​​the top is larger than the area of ​​the open container. The fresh water collection container 13 has a support 15 inside, and the top of the support 15 fixes the open container 12.

[0051] The support 15 can be independently arranged vertically, or obliquely, or made integrally with the fresh water collection container 13. The truncated cone-shaped collection container with a larger top and a smaller bottom is conducive to the flow and collection of condensed droplets on the inner wall of the transparent cover 14.

[0052] Embodiment 2: A hemispherical glass transparent cover is arranged above the open container 12, and the hemispherical glass transparent cover is buckled with the fresh water collection container 13. The diameter of the hemispherical glass transparent cover is larger than the cross-sectional diameter of the open container 12, and smaller than the cross-sectional diameter of the top of the fresh water collection container 13. Such a design ensures that there is a sufficiently large evaporation space and that the condensed droplets can be smoothly recovered by the fresh water collection container.

[0053] For example, the radius of the transparent glass cover is 14 cm. During the evaporation process, water vapor condenses on the glass cover to form small droplets. As the evaporation time increases, the droplets on the surface of the glass cover gradually grow larger, and finally flow downward to the fresh water collection container 13 under the action of gravity.

[0054] Embodiment 3: A pipe 16 is provided at the bottom of the fresh water collection container 13, and the pipe 16 extends to the top of the electrolytic cell 21. The collected fresh water flows into the electrolytic cell 21 through the pipe 16. The collection is carried out in a pipe-connected manner, which facilitates the arrangement and disassembly of each system of the device and can be operated both indoors and outdoors.

[0055] Embodiment 4, the preparation process of the solar evaporator with a three-dimensional bionic microstructure on the upper part and a microchannel on the lower part is as follows: the evaporator is modeled on a computer using SolidWorks software, and then the model is saved in STL format, the STL file of the model is imported into the slicing software for slicing and obtaining a 2D slice model image, and the image is imported into a light-curing 3D printer. At the same time, after the modeling is completed, the materials are prepared, a certain mass of carbon nanotubes and photosensitive resin are weighed out by a balance, and the mass ratio of carbon nanotubes to photosensitive resin is 1:100. The role of carbon nanotubes is to improve the spectral absorption rate of the surface of the solar evaporator. The carbon nanotubes are added to the resin for mixing for 3D printing manufacturing, the weighed carbon nanotubes and photosensitive resin are poured into a beaker for mixing, and a magnetic stirrer is used to fully stir them to make them evenly mixed, and the stirring time needs to be greater than 30 minutes. If they are still not evenly mixed after stirring for 30 minutes, they need to continue stirring until they are fully mixed. After stirring, the mixed resin is poured into the printing tank of the light-curing 3D printer, and then printing is started. The preparation process of ordinary evaporators is the same as that of 3D bionic solar evaporators, and the difference between the two lies in their shapes; for example, large-area (14cm×14cm) evaporators and small-area (2cm×2cm) evaporators are both manufactured by the above method.

[0056] After printing, remove the evaporation device from the printing platform and ultrasonically clean the evaporation device with 95% ethanol solution for 2 minutes. After cleaning, remove the evaporator and blow off the ethanol solution on the surface of the evaporator with a nitrogen pump. Repeat 3 times to ensure that there is no residual ethanol solution and resin on the surface of the evaporator. Raise the temperature in the vacuum drying oven to 80°C and place the evaporator in the drying oven for 1 hour to ensure that all the moisture in the evaporator is removed. After drying, use oxygen plasma to treat the upper surface of the evaporator so that the contact angle of the upper surface is less than 10°, showing superhydrophilicity, and then let the evaporator stand for 30 minutes to cool to room temperature.

[0057] With such a design, the solar evaporator obtained above has Janus characteristics, which improves the evaporation efficiency while preventing salt crystallization when the device works in a harsh seawater environment with high salt concentration, significantly improving the durability of the device and increasing its service life.

[0058] Example 5: After the salt tolerance test was completed, a large-area solar evaporator was designed with an upper surface working area of ​​14 cm×14 cm, which was manufactured using photocuring 3D printing technology.

[0059] A large cylindrical container is designed as an open container 12, with an inner radius of 12.2 cm, a wall thickness of 0.5 cm, and a height of 5 cm, and is manufactured by fused deposition modeling (FDM) 3D printing technology. The container is used to store salt water. During the evaporation process, the solar evaporator 11 is placed in the open container 12 and floats above the salt water to form an evaporated salt water container. The fresh water collection container 13 for desalinated water is truncated cone-shaped, and its radius gradually decreases from top to bottom. The inner radius of the top circle of the container is 14.4 cm, the inner radius of the bottom circle of the container is 2 cm, and the height of the container is 9 cm. There is a support with a height of 9 cm in the middle of the fresh water collection container 13, which is used to support and fix the open container 12 for evaporating salt water. There is a pipe at the bottom of the fresh water collection container 13 for transporting desalinated water to the electrolytic cell.

[0060] Embodiment 6: The substrate of the film with Janus structure is a grid plate, and the upper surface of the grid plate is coated with a hydrophobic layer, and the hydrophobic layer can form an air film when immersed in water. Due to the difference in wettability of the interface between the super-hydrophobic top of the grid and the hydrophilic bottom, an asymmetric wettability structure is formed, and a Laplace pressure difference is formed at the gas-liquid-solid three-phase interface. Under the action of the Laplace pressure difference, the bubbles are captured by the grid, and the bubbles are quickly manipulated and transported to the top of the grid.

[0061] The electrolytic cell material of this embodiment is a transparent acrylic plate with a size of 25 cm long × 25 cm wide × 25 cm high. The electrolyte is a dilute sulfuric acid solution with a pH of 1. The volume of the electrolyte is 11 L. The power supply system uses a solar cell. The solar cell provides the electrical energy consumed by the electrolysis process. The battery has the function of charging and discharging at the same time, which is a prior art.

[0062] Furthermore, a grid plate with a size of 5cm×5cm is manufactured by photocuring 3D printing technology, in which the smallest unit of the grid is 0.4cm×0.4cm. The material of the grid plate does not need to be added with carbon nanotubes, but only needs to be cured layer by layer in the printer through photosensitive resin. 16 5cm×5cm grids are processed, and superhydrophobic material is sprayed on the upper surface of the grid. The superhydrophobicity on the upper surface of the grid plate and the hydrophilicity on the lower surface of the substrate form a Janus film. When the Janus film is completely immersed in water, a smooth air film is formed on the surface treated with superhydrophobicity. And 16 5cm×5cm grids are pieced together (for example, bonded by curing resin and cured with ultraviolet light) to form a large-area Janus grid of 20cm×20cm.

[0063] Furthermore, the electrolytic cathode material is copper, and a 20cm×20cm copper sheet is pasted to a 22cm×22cm bottom plate, which is a glass plate, and the glass bottom plate fixes the copper sheet and sinks it to the bottom of the electrolytic cell. Then a 20cm×20cm large-area Janus grid is fixed above the copper sheet, and the spacing between the lower surface of the grid plate and the surface of the copper sheet is 300-600um (for example, the spacing is 0.6cm, and the diameter of the hydrogen bubbles generated on the copper surface during the electrolysis process is about 0.6cm); then a conductive copper foil with a width of 2cm is connected to the cathode copper plate 22 (working electrode) at one end, and the other end is connected to the negative electrode wire of the solar cell outside the electrolytic cell to act as a wire, and it is sealed with a waterproof tape to prevent the electrolysis process from reacting on its surface.

[0064] Furthermore, an inverted flow guide hopper 23 is placed above the cathode (for example, the flow guide hopper 23 for a small test can be an inverted funnel, and the gas collecting pipe 24 can be a measuring cylinder, which is fixed in the electrolytic cell 21 by a bracket 27). The two ends of the flow guide hopper 23 are open, one end is a large opening, and the other end is a small opening. The large opening is a square with a side length of 25 cm, which can fully cover the entire cathode including the large area of ​​the film 25 with a Janus structure and the glass bottom plate. The small opening of the flow guide hopper 23 is inserted into the inverted gas collecting pipe filled with electrolyte, and the growing large hydrogen bubbles float upward, and the hydrogen bubbles generated on both sides drift along the inner wall of the flow guide hopper 23 to the gas collecting pipe 24. The flow guide hopper 23 plays a role of diversion, and finally the hydrogen is collected in the gas collecting pipe 24 by the drainage method.

[0065] Furthermore, a square graphite plate with a thickness of 0.5 cm is used as the anode plate 26, and the carbon plate is placed vertically in the electrolyte with one quarter of it exposed outside the electrolyte and fixed, and the wire coming out of the positive electrode of the solar cell is connected to the exposed part of the carbon plate.

[0066] Example 7: Based on the ultra-durable solar-driven seawater electrolysis hydrogen production device of the above embodiment or any embodiment, an ultra-durable solar-driven seawater electrolysis hydrogen production method is proposed, which comprises the following steps:

[0067] S1, placing seawater in the open container 12, placing the solar evaporator 11 in the open container 12 filled with seawater, floating the solar evaporator 11 on the water, and covered with a transparent cover 14;

[0068] S2, the light source is directed to the solar evaporator 11, the seawater evaporates, and the salt water is transported upward along the microchannel. Under the action of Laplace pressure, a thin water film is formed on the surface of the three-dimensional bionic microstructure. The photothermal conversion of solar energy forms a temperature gradient inside the water film and forms a Marangoni effect. The salt water microcirculation of the Marangoni effect prevents the crystallization of salt;

[0069] S3, the transparent cover 14 condenses the generated water vapor into droplets, and the droplets flow into the fresh water collection container 13 under the action of gravity, and the collected fresh water flows into the electrolytic cell 21 through the pipeline;

[0070] S4, the power supply system supplies electricity to the cathode copper plate 22 and the anode graphite plate 26 to perform water electrolysis reaction. During the electrolysis process, the air film generated by the thin film with Janus structure allows the hydrogen bubbles generated by electrolysis to be quickly transported in one direction after passing through the airway. Under the action of the hydrophobic layer, the hydrogen bubbles are caused to gather above the hydrophobic layer. When they gather to a certain volume, the bubbles float upward, and under the diversion action of the diversion bucket 23, the hydrogen is collected in the gas collecting pipe 24.

[0071] Based on solar-driven seawater evaporation technology, water vapor is condensed and collected into desalinated water through a hemispherical transparent glass cover. The collected desalinated water flows into the electrolytic cell through a pipeline, where water electrolysis reaction is carried out to eventually generate hydrogen.

[0072] Reference Figure 8-Figure 10 , Figure 8 The experiment shows the freshwater collection rate of the hydrogen production device in this scheme after 8 days of circulating evaporation of brine. It is found that except on rainy days, the freshwater collection rate of the ultra-durable solar-driven seawater evaporation and freshwater collection device is as low as 0.44L m -2 h -1 , the highest is 0.58L m -2 h -1 .

[0073] Fig. 9 The relationship between the amount of hydrogen collected and time when the device is working outdoors shows that the collection rate reaches 1.75-2L m -2 h -1 .

[0074] As an embodiment, the electric energy in the electrolysis process is provided by a solar cell, and the cell can be charged while in use, and the electric energy obtained during the day can be used by the electrolysis device of the present invention for more than 24 hours. Fig. 9 It can be concluded that the hydrogen production device can collect 85mL of hydrogen in 1 hour, and the water consumed in this process is only 0.068mL. The fresh water collection device tested above can collect at least 8.62mL of water in 1 hour, which is much greater than the water consumption of hydrogen production by electrolysis. Therefore, the comprehensive experimental test results show that the ultra-durable solar-driven seawater electrolysis hydrogen production device can work continuously for 24 hours a day.

[0075] In order to verify the stability of the hydrogen production device, the inventor conducted 8 cycles of testing on the hydrogen production device outdoors for 1 hour. Fig.10 As shown, the hydrogen production device has excellent stability performance.

[0076] The present invention has been disclosed as above with preferred implementation cases, but it is not intended to limit the present application. Any technician familiar with the profession can make slight changes or modifications to equivalent implementation cases with equivalent changes by using the above-disclosed structures and technical contents without departing from the scope of the technical solution of the present application, which still fall within the scope of the technical solution of the present application.

Claims

1. An ultra-durable solar-driven seawater electrolysis hydrogen production device, comprising: A seawater evaporation fresh water collection system is used to recover fresh water and feed it into an electrolytic hydrogen production system. The seawater evaporation fresh water collection system comprises a connected solar evaporator, an open container, a fresh water collection container and a transparent cover; the solar evaporator, the open container and the transparent cover enclose an evaporation space; Electrolysis hydrogen production system, used for water electrolysis to produce hydrogen; A power supply system, used to provide electrical energy to the electrolysis hydrogen production system; Features: The solar evaporator is an evaporator having a three-dimensional bionic microstructure on the upper part and a microchannel on the lower part, wherein the three-dimensional bionic microstructure has superhydrophilicity, and the bottom interface of the microchannel has hydrophilicity, and the superhydrophilicity enables water flowing out of the microchannel to diffuse along the three-dimensional bionic microstructure; The electrolytic hydrogen production system comprises an electrolytic cell, a cathode copper plate, a flow guide hopper, a gas collecting pipe and a film with a Janus structure, wherein the film can produce a layer of air film when immersed in water; the electrolytic cell is suitable for placing an electrolyte; the anode graphite plate is placed in the electrolytic cell, the cathode copper plate is laid flat on the bottom of the electrolytic cell, the film is arranged on the upper surface of the cathode copper plate and there is a gap between the two, the gap allows hydrogen bubbles to be generated on the surface of the cathode copper plate during electrolysis, the film has an airway, the flow guide hopper is arranged above the film, the flow guide hopper inlet covers the film, the flow guide hopper outlet is arranged in the inverted gas collecting pipe inlet, the gas collecting pipe is suitable for being filled with water for collecting hydrogen, and the anode graphite plate and the cathode copper plate are electrically connected to the positive and negative poles of the power supply system accordingly.

2. According to claim 1, a super durable solar-driven seawater electrolysis hydrogen production device is characterized by: The substrate of the film with the Janus structure is a grid plate, the upper surface of the grid plate is coated with a hydrophobic layer, and the hydrophobic layer can form an air film when immersed in water.

3. According to claim 2, an ultra-durable solar-driven seawater electrolysis hydrogen production device is characterized by: The grid plate is made by photo-curing 3D printing.

4. According to claim 1, a super durable solar-driven seawater electrolysis hydrogen production device is characterized by: The fresh water collection container is in the shape of a truncated cone, and the cross-sectional area of ​​the top is larger than the area of ​​the open container. The collection container is provided with a support inside, and the top of the support fixes the open container.

5. According to claim 1, a super durable solar-driven seawater electrolysis hydrogen production device is characterized by: A hemispherical glass transparent cover is arranged above the open container, and the hemispherical glass transparent cover is buckled with the fresh water collection container.

6. According to claim 1, a super durable solar-driven seawater electrolysis hydrogen production device is characterized by: A pipe is provided at the bottom of the fresh water collection container, and the pipe extends above the electrolytic cell. The collected fresh water flows into the electrolytic cell through the pipe.

7. According to claim 1, a super durable solar-driven seawater electrolysis hydrogen production device is characterized by: The freshwater collection container and open container were made by fused deposition modeling 3D printing, and the solar evaporator was made by photo-stereolithography 3D printing.

8. The ultra-durable solar-driven seawater electrolysis hydrogen production device according to claim 1, characterized in that: The solar evaporator is obtained by: First, the evaporator is modeled using SolidWorks software to obtain a 3D model, and then the 3D model is saved in STL format, the STL file of the 3D model is imported into a slicing software for slicing to obtain a 2D slice model image, and the image is imported into a light-curing 3D printer; At the same time, carbon nanotubes and photosensitive resins with a mass ratio of 1:100 are selected, and the prepared carbon nanotubes and photosensitive resins are poured into a container and stirred until they are evenly mixed. After the stirring is completed, the mixed material is poured into the printing tank of a light-curing 3D printer for printing; The printed evaporation device is removed from the printing platform and ultrasonically cleaned with a 95% ethanol solution. After cleaning, the evaporation device is taken out and the ethanol solution on the surface of the evaporation device is blown off with a nitrogen pump. This is repeated several times until there is no residual ethanol solution and resin on the surface of the evaporation device. After that, it is vacuum dried to remove all moisture. After drying, the upper part of the evaporator is treated with an oxygen plasma method to make the upper surface super hydrophilic. The evaporation device is then left to stand until room temperature to obtain a solar evaporator with salt resistance in saturated brine.

9. An ultra-durable solar-driven seawater electrolysis method for producing hydrogen, characterized in that: Based on the solar-driven seawater electrolysis hydrogen production device according to any one of claims 1 to 8, the hydrogen production method comprises the following steps: S1. placing seawater in the open container, placing the solar evaporator in the open container filled with seawater, floating the solar evaporator on the water, and covering it with a transparent cover; S2. The light source is directed to the solar evaporator, the seawater evaporates, and the salt water is transported upward along the microchannel. Under the action of Laplace pressure, a thin water film is formed on the surface of the three-dimensional bionic microstructure. The photothermal conversion of solar energy forms a temperature gradient inside the water film and forms a Marangoni effect. The salt water microcirculation of the Marangoni effect prevents the crystallization of salt. S3, the glass cover condenses the generated water vapor into droplets, and the droplets flow into the fresh water collection container under the action of gravity, and the collected fresh water flows into the electrolytic cell through the pipeline; S4. The power supply system supplies electricity to the cathode copper plate and the anode graphite plate to perform water electrolysis. During the electrolysis process, the air film generated by the film with the janus structure allows the hydrogen bubbles generated by the electrolysis to be quickly transported in one direction after passing through the airway. Under the action of the hydrophobic layer, the hydrogen bubbles are caused to gather above the hydrophobic layer. When they gather to a certain volume, the bubbles float upward, and under the diversion action of the diversion bucket, the hydrogen is collected in the gas collecting pipe.

10. The ultra-durable solar-driven seawater electrolysis hydrogen production method according to claim 9, characterized in that: Fresh water collection rate is 0.44Lm -2 h -1 -0.58Lm -2 h -1 , hydrogen collection rate is 1.75-2Lm -2 h -1 .

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