A photocatalytic hydrogen production device based on air water taking of hygroscopic hydrogel

Abstract

The application relates to a kind of photocatalytic water vapor hydrogen production devices based on hygroscopic hydrogel air water, and belongs to the field of photocatalytic hydrogen production.The photocatalytic water vapor hydrogen production devices include a gas collection mechanism, an interface catalytic reaction mechanism, an air water extraction mechanism, a sealing mechanism and an exhaust sampling mechanism.The interface catalytic reaction mechanism and the air water extraction mechanism are both arranged inside the gas collection mechanism.The interface catalytic reaction mechanism is arranged above the air water extraction mechanism.The exhaust sampling mechanism is arranged on the gas collection mechanism.The sealing mechanism is arranged inside the gas collection mechanism and connected with the gas collection mechanism.The photocatalytic water vapor hydrogen production devices can absorb water vapor from ambient air as the water source for photocatalytic hydrogen production, and perform interface photocatalytic water vapor hydrogen production under the action of solar desorption.

Description

TECHNICAL FIELD

[0001] The application relates to the field of photocatalytic hydrogen production, in particular to a photocatalytic water vapor hydrogen production device based on air water extraction of hygroscopic hydrogel. BACKGROUND

[0002] With the aggravation of global greenhouse effect and environmental pollution, it is urgent to develop green clean energy. In recent years, hydrogen energy fuel has attracted much attention due to its zero emission, no pollution and high efficiency, and has advantages such as low self-weight and high energy density, and is widely used in the fields of aerospace, fuel cells, automobiles and ships, etc. Therefore, hydrogen energy is considered as the "cleanest energy in the world", and the development of low-cost and high-efficiency hydrogen production device has great significance for the transformation and development of energy structure.

[0003] Photocatalytic hydrogen production is a new green hydrogen production technology, which is based on the decomposition of water system of semiconductor nanoparticles, uses sunlight as driving force and water as raw material, and has advantages such as low cost, simplicity and environmental protection. However, the current photocatalytic system mainly disperses photocatalysts in large water area for photocatalytic process, which is prone to problems such as catalyst deposition and low temperature of catalytic system, and the catalyst can only use 5%-7% of the absorbed solar radiation energy for photocatalytic decomposition of water, and other solar radiation energy is used for heating the water solution in the large water area. However, due to the large water area, the actual catalytic yield is low, the operation performance is reduced, the energy utilization rate is extremely low, and the large-scale commercial application is hindered. Moreover, since real-time hydrogen production needs a fixed water source, it is difficult to produce hydrogen in some areas where water is extremely scarce but hydrogen is needed, and the cost is high, which limits the development of hydrogen energy in these areas to a certain extent. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a photocatalytic water vapor hydrogen production device based on air water extraction of hygroscopic hydrogel, which can absorb water vapor from the surrounding air as the water source for photocatalytic hydrogen production, and perform interface photocatalytic water vapor hydrogen production under the desorption effect of sunlight.

[0005] The technical solution for solving the above technical problem is as follows: a photocatalytic water vapor hydrogen production device based on air water extraction of hygroscopic hydrogel, comprising: a gas collection mechanism, an interface catalytic reaction mechanism, an air water extraction mechanism, a sealing mechanism and an exhaust sampling mechanism, the interface catalytic reaction mechanism and the air water extraction mechanism are arranged inside the gas collection mechanism, the interface catalytic reaction mechanism is arranged above the air water extraction mechanism, the exhaust sampling mechanism is arranged on the gas collection mechanism, and the sealing mechanism is arranged inside the gas collection mechanism and connected with the gas collection mechanism.

[0006] The beneficial effects of the present application are that the air water taking mechanism is beneficial to adsorb water vapor in the air around the device as raw material for photocatalytic hydrogen production and store it in the gas collecting mechanism, which on the one hand reduces the hydrogen production cost in water shortage areas, and on the other hand reduces the storage space of hydrogen production raw material water, thereby improving the efficiency of the interface catalytic reaction mechanism in collecting solar energy and using solar energy to heat and warm the raw material water, thereby improving the overall efficiency of hydrogen production; the sealing mechanism is beneficial to improve the sealing performance of the entire device and reduce the leakage of water vapor and hydrogen produced; the exhaust sampling mechanism is beneficial to exhaust the air in the gas collecting mechanism before hydrogen production, and simultaneously sample and detect the hydrogen in the gas collecting mechanism during hydrogen production.

[0007] Based on the above technical solutions, the present application can be further improved as follows.

[0008] Further, the gas collecting mechanism comprises a flange top plate, an annular sealing plate and a flange bottom disc, the flange top plate and the flange bottom disc are connected to the top end and the bottom end of the annular sealing plate one by one, the interface catalytic reaction mechanism is arranged between the flange top plate and the annular sealing plate, and the air water taking mechanism is arranged between the flange bottom disc and the annular sealing plate.

[0009] The beneficial effects of the above further scheme are that the annular sealing plate cooperates with the flange top plate and the flange bottom disc to form a sealed space for storing the moisture in the air collected by the air water taking mechanism and the hydrogen produced by the interface catalytic reaction mechanism under the action of solar energy.

[0010] Further, the quartz glass is embedded in the middle of the flange top plate, the first annular groove is arranged at the bottom end of the flange top plate, the quartz glass is arranged in the middle of the first annular groove, the circular groove and the second annular groove are arranged in the middle of the top end of the flange bottom disc, and the circular groove is arranged in the middle of the second annular groove.

[0011] The beneficial effects of the above further scheme are that the quartz glass is beneficial to transmit sunlight into the annular sealing plate, on the one hand, to warm and evaporate the moisture adsorbed in the air into water vapor under the action of solar energy, and on the other hand, to improve the temperature in the annular sealing plate through solar energy, thereby improving the efficiency of photocatalytic reaction and hydrogen production efficiency.

[0012] Further, the air water taking mechanism comprises a hygroscopic hydrogel and a carrier table, the carrier table is a plate-shaped structure which is adaptively installed in the circular groove of the flange bottom disc and has a groove in the middle of the top end, and the hygroscopic hydrogel is adaptively installed in the groove in the middle of the top end of the carrier table.

[0013] The beneficial effect of the further scheme is that the hygroscopic hydrogel is conducive to absorbing moisture in the surrounding air and storing it in the object table, providing raw materials for photocatalytic hydrogen production.

[0014] Further, the hygroscopic hydrogel is a composite hydrogel formed by mixing a hygroscopic salt with a mass fraction of 30%-45% and a hydrophilic polymer.

[0015] The beneficial effect of the further scheme is that the hygroscopic hydrogel is conducive to absorbing moisture in the air as raw materials for hydrogen production, solving the problem of insufficient raw materials for hydrogen production in water-deficient areas.

[0016] Further, the sealing mechanism comprises a plurality of fastening bolts, two sealing washers and a plurality of nuts, the two sealing washers are one-to-one correspondingly installed in the first and second annular grooves, the plurality of fastening bolts are arranged around the annular sealing plate, the plurality of fastening bolts penetrate the flange top plate and the annular sealing plate, and are one-to-one correspondingly connected with the plurality of nuts.

[0017] The beneficial effect of the further scheme is that the sealing washer is conducive to improving the sealing performance between the annular sealing plate and the flange top plate and the flange bottom plate, and the fastening bolt cooperates with the nut to further improve the sealing performance.

[0018] Further, the exhaust sampling mechanism comprises two quick-connect valves, a protective gas inlet pipe, a protective gas outlet pipe, a sealing rubber plug and a sampling needle, the quick-connect valves penetrate the sidewall of the annular sealing plate, the two quick-connect valves are one-to-one correspondingly connected with the protective gas inlet pipe and the protective gas outlet pipe at the end away from the annular sealing plate, the sealing rubber plug is sealingly connected with the through hole on the sidewall of the annular sealing plate, and the sampling needle is detachably penetrated through the sealing rubber plug.

[0019] The beneficial effect of the further scheme is that the quick-connect valve cooperates with the protective gas inlet pipe and the protective gas outlet pipe, which is conducive to injecting protective gas such as nitrogen (N2) into the annular sealing plate before hydrogen production, improving the purity of the produced hydrogen; the sampling needle cooperates with the sealing rubber plug, which is conducive to sampling and detecting the hydrogen concentration in the annular sealing plate during hydrogen production.

[0020] Further, the interface catalytic reaction mechanism comprises an annular gasket, a photocatalytic layer and a hydrophobic membrane, the outer diameters of the annular gasket and the hydrophobic membrane are the same, the annular gasket is sealingly installed on the hydrophobic membrane, and the photocatalytic layer is adaptively installed in the catalytic reaction tank composed of the annular gasket and the hydrophobic membrane.

[0021] The beneficial effect of the further scheme is that the annular gasket and the hydrophobic membrane can form a catalytic reaction tank, providing a position for the installation of the photocatalytic layer.

[0022] Further, the photocatalytic layer is a powder solid formed by mixing the photocatalyst, the sacrificial agent and the co-catalyst.

[0023] The beneficial effect of the above further solution is that it is conducive to improving the stability of the catalytic reaction, the efficiency of the catalytic reaction and the purity of the hydrogen gas prepared. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 An overall structural explosion diagram is provided for the embodiment of the present application;

[0025] Figure 2 An overall structural schematic diagram is provided for the embodiment of the present application;

[0026] Figure 3 An interface photocatalytic water vapor and traditional large water area catalytic hydrogen production rate comparison schematic diagram is provided for the embodiment of the present application;

[0027] Figure 4 A complete working process schematic diagram is provided for the embodiment of the present application;

[0028] Figure 5 A hydrogen production under different light intensity schematic diagram is provided for the embodiment of the present application;

[0029] Figure 6 A continuous cycle characteristic test schematic diagram is provided for the embodiment of the present application;

[0030] Figure 7 A real outdoor hydrogen production experiment result schematic diagram is provided for the embodiment of the present application.

[0031] In the drawings, the components represented by each number are listed as follows:

[0032] 1, gas collection mechanism; 2, interface catalytic reaction mechanism; 3, air water collection mechanism; 4, sealing mechanism; 5, exhaust sampling mechanism; 11, flange top plate; 12, annular sealing plate; 13, flange bottom plate; 21, annular gasket; 22, photocatalytic layer; 23, hydrophobic membrane; 31, hygroscopic hydrogel; 32, object table; 41, fastening bolt; 42, sealing gasket; 43, nut; 51, quick coupling valve; 52, protective gas inlet pipe; 53, protective gas outlet pipe; 54, sealing rubber plug; 55, sampling needle. DETAILED DESCRIPTION

[0033] The principles and features of the present application are described below, and the examples are only used to explain the present application, and are not used to limit the scope of the present application.

[0034] As Figures 1 to 2As shown, a photocatalytic water vapor hydrogen production device based on air water extraction using hygroscopic hydrogel includes: a gas collection mechanism 1, an interfacial catalytic reaction mechanism 2, an air water extraction mechanism 3, a sealing mechanism 4, and an exhaust sampling mechanism 5. The interfacial catalytic reaction mechanism 2 and the air water extraction mechanism 3 are both disposed inside the gas collection mechanism 1. The interfacial catalytic reaction mechanism 2 is disposed above the air water extraction mechanism 3. The exhaust sampling mechanism 5 is disposed on the gas collection mechanism 1. The sealing mechanism 4 is disposed inside the gas collection mechanism 1 and connected to the gas collection mechanism 1.

[0035] The beneficial effects of this invention are as follows: the air-water collection mechanism is advantageous for adsorbing water vapor in the air surrounding the device and using it as a raw material for photocatalytic hydrogen production, and storing it in the gas collection mechanism. On the one hand, this reduces the cost of hydrogen production in water-scarce areas; on the other hand, by reducing the storage space for the hydrogen production raw material water, it improves the efficiency of using solar energy collected by the interfacial catalytic reaction mechanism to heat the raw material water, thereby improving the overall efficiency of hydrogen production. The sealing mechanism is advantageous for improving the sealing performance of the entire device and reducing the leakage of water vapor and produced hydrogen. The exhaust sampling mechanism is advantageous for venting the air in the gas collection mechanism before hydrogen production, and simultaneously sampling and detecting the hydrogen in the gas collection mechanism during the hydrogen production process.

[0036] Preferred, such as Figure 1 As shown, the gas collection mechanism 1 includes: a flange top plate 11, an annular sealing plate 12, and a flange base plate 13. The flange top plate 11 and the flange base plate 13 are connected to the top and bottom ends of the annular sealing plate 12 respectively. The interface catalytic reaction mechanism 2 is disposed between the flange top plate 11 and the annular sealing plate 12. The air-water collection mechanism 3 is disposed between the flange base plate 13 and the annular sealing plate 12.

[0037] It should be noted that, in a preferred embodiment of the present invention, the flange top plate 11, the annular sealing plate 12, and the flange base plate 13 are made of acrylic or nylon, which is not only low in cost but also does not absorb light, thus improving the utilization rate of solar energy.

[0038] The advantages of adopting the above preferred solution are: the annular sealing plate, together with the flange top plate and the flange bottom plate, helps to form a sealed space to store the moisture in the air collected by the air water intake mechanism and the hydrogen produced by the interface catalytic reaction mechanism after catalyzing water vapor under the action of solar energy.

[0039] Preferred, such as Figure 1As shown, a quartz glass is embedded in the middle of the flange top plate 11, a first annular groove is provided at the bottom end of the flange top plate 11, and the quartz glass is located in the middle of the first annular groove. A circular groove and a second annular groove are provided in the middle of the top end of the flange base plate 13, and the circular groove is located in the middle of the second annular groove.

[0040] The beneficial effects of adopting the above-mentioned preferred scheme are: quartz glass facilitates the transmission of sunlight into the annular sealing plate. On the one hand, under the action of solar energy, the moisture adsorbed in the air is heated and evaporated into water vapor. On the other hand, the temperature inside the annular sealing plate is increased by solar energy, thereby improving the efficiency of photocatalytic reaction and increasing hydrogen production efficiency.

[0041] Preferred, such as Figure 1 As shown, the air water collection mechanism 3 includes: a hygroscopic hydrogel 31 and a platform 32. The platform 32 is a plate-shaped structure adapted to be installed in the circular groove of the flange base 13, and has a groove in the middle of the top. The hygroscopic hydrogel 31 is adapted to be installed in the groove in the middle of the top of the platform 32.

[0042] It should be noted that when the device is off or at night without sunlight, the hygroscopic hydrogel 31 needs to be removed and placed in the air. Due to its strong hydrophilicity, the hydrogel will absorb moisture from the air and store it inside, thus completing the air-to-water regeneration process. When the device is running, placing the entire device under sunlight causes the moisture inside the hydrogel to absorb solar energy and evaporate. Under the catalytic action of the photocatalytic layer 22, this evaporates and undergoes a decomposition reaction to generate hydrogen gas.

[0043] The beneficial effects of adopting the above preferred solution are: the hygroscopic hydrogel is conducive to absorbing moisture from the surrounding air and storing it in the stage, providing raw materials for the photocatalytic hydrogen production reaction.

[0044] Preferably, the hygroscopic hydrogel 31 is a composite hydrogel formed by mixing a hygroscopic salt with a mass fraction of 30%-45% with a hydrophilic polymer.

[0045] It should be noted that, in the preferred embodiment of the present invention, the hygroscopic salt in the hygroscopic hydrogel 31 mixture is often selected from substances such as calcium chloride (CaCl2), lithium bromide (LiBr), lithium chloride (LiCl), zinc chloride (ZnCl2), and sodium sulfate (Na2SO4); the hydrophilic polymer is often selected from monomers or polymers such as polyacrylamide, polyethylene glycol, polyvinyl alcohol, ribomeric polysaccharide, and sodium alginate.

[0046] The beneficial effects of adopting the above-mentioned preferred solution are: the hygroscopic hydrogel is conducive to absorbing moisture from the air and using it as a raw material for hydrogen production, thus solving the problem of insufficient raw materials for hydrogen production in water-scarce areas.

[0047] Preferred, such as Figure 1 As shown, the sealing mechanism 4 includes: multiple fastening bolts 41, two sealing washers 42 and multiple nuts 43. The two sealing washers 42 are fitted one-to-one into the first annular groove and the second annular groove. The multiple fastening bolts 41 are arranged around the annular sealing plate 12. The multiple fastening bolts 41 pass through the flange top plate 11 and the annular sealing plate 12, and are threadedly connected to the multiple nuts 43 one-to-one.

[0048] The advantages of adopting the above-mentioned preferred solution are: the sealing gasket helps to improve the sealing performance between the annular sealing plate and the flange top plate and flange base plate, while the fastening bolts and nuts help to further enhance the sealing performance.

[0049] Preferred, such as Figure 1 As shown, the exhaust sampling mechanism 5 includes: two quick-connect valves 51, a protective gas inlet pipe 52, a protective gas outlet pipe 53, a sealing rubber plug 54, and a sampling needle 55. The quick-connect valves 51 are disposed through the side wall of the annular sealing plate 12. The ends of the two quick-connect valves 51 away from the annular sealing plate 12 are connected one-to-one to the protective gas inlet pipe 52 and the protective gas outlet pipe 53. The sealing rubber plug 54 is sealed to the through hole on the side wall of the annular sealing plate 12. The sampling needle 55 is detachably inserted through the sealing rubber plug 54.

[0050] It should be noted that, in addition to serving as conduits for introducing protective gas before hydrogen production and venting air from the annular sealing plate 12, the protective gas inlet pipe 52 and the protective gas outlet pipe 53 can also be used in conjunction with the quick-connect valve 51 to vent the hydrogen produced in the annular sealing plate 12 after hydrogen production.

[0051] Furthermore, the fact that the sampling needle 55 can detachably penetrate the sealing rubber plug 54 means that during the hydrogen production process, the hydrogen produced in the annular sealing plate 12 needs to be sampled and its concentration detected at regular intervals. The sampling method is to insert the sampling needle 55 into the sealing rubber plug 54, and the hydrogen in the annular sealing plate 12 can then pass through the sampling needle 55. After sampling, the sampling needle 55 is pulled out of the sealing rubber plug 54. Under the action of the rubber material of the sealing rubber plug 54, the channel that originally allowed the sampling needle 55 to enter and exit is closed, so that the entire sampling process will not damage the sealing performance of the annular sealing plate 12.

[0052] The advantages of adopting the above-mentioned preferred scheme are: the quick-connect valve, in conjunction with the protective gas inlet pipe and the protective gas outlet pipe, facilitates the injection of protective gas, such as nitrogen (N2), into the annular sealing plate before hydrogen production, thereby improving the purity of the produced hydrogen; the sampling needle, in conjunction with the sealing rubber stopper, facilitates the sampling and detection of the hydrogen concentration in the annular sealing plate during the hydrogen production process.

[0053] Preferred, such as Figure 1 As shown, the interface catalytic reaction mechanism 2 includes: an annular gasket 21, a photocatalytic layer 22, and a hydrophobic membrane 23. The annular gasket 21 and the hydrophobic membrane 23 have the same outer diameter. The annular gasket 21 is sealed and installed on the hydrophobic membrane 23. The photocatalytic layer 22 is adapted and installed in the catalytic reaction tank formed by the annular gasket 21 and the hydrophobic membrane 23.

[0054] It should be noted that, in a preferred embodiment of the present invention, the hydrophobic membrane 23 is selected from PTFE (polytetrafluoroethylene), PVDF (polyvinylidene difluoride), or PP (polypropylene) hydrophobic membranes, which is beneficial to improving the hydrophobic and breathable properties of the hydrophobic membrane 23; the thickness of the hydrophobic membrane 23 is between 0.1 mm and 0.16 mm, the porosity is greater than 60%, the contact angle is greater than 110°, and the pore size is between 0.1 μm and 2 μm.

[0055] The advantages of adopting the above preferred solution are: the annular gasket and the hydrophobic film can form a catalytic reaction tank, providing a location for the installation of the photocatalytic layer.

[0056] Preferably, the photocatalytic layer 22 is a powdered solid composed of a photocatalyst, a sacrificial agent, and a co-catalyst.

[0057] It should be noted that, in the preferred embodiment of the present invention, the photocatalyst is selected from micro / nano particles with a suitable relative position between the valence band and the conduction band, and a particle diameter of less than 200 nm, such as titanium dioxide (TiO2), molybdenum sulfide (MoS2), cadmium sulfide (CdS), carbon nitride (C3N4), cuprous oxide (Cu2O), zinc indium sulfide (ZnIn2S4), and indium sulfide (CdIn2S4), which is beneficial to improving the efficiency of photocatalytic reaction. The phrase "suitable relative position between the valence band and the conduction band" means that the redox ability of holes and electron pairs is determined by the relative position of the conduction band and the valence band. When the minimum potential of the conduction band of the photocatalyst is more negative than the hydrogen evolution half-reaction potential, and the maximum potential of the valence band is more positive than the oxygen evolution half-reaction potential, photocatalytic water splitting is thermodynamically feasible. The band gap width between the conduction band and the valence band is called the band gap. The narrower the band gap, the wider the absorption spectrum range.

[0058] The sacrificial agent is selected from sulfide, sulfite, thiosulfate, alcohol or ammonia, such as methanol (CH3OH), sodium sulfide (Na2S), sodium sulfite (Na2SO3), which has strong hole binding ability, can effectively inhibit the occurrence of oxidation half-reaction in the water molecule cracking reaction, and make the prepared hydrogen more pure.

[0059] The assistant catalyst is selected from platinum (Pt), silver (Ag) and the like, which can effectively increase the catalytic active site, make the surface catalytic reaction easy to occur, speed up the reaction process, cooperate with the sacrificial agent to consume holes in time, and improve the stability of the overall catalytic reaction.

[0060] The above preferred scheme has the beneficial effects of improving the stability of the catalytic reaction, the efficiency of the catalytic reaction, and the purity of the prepared hydrogen.

[0061] The working process of the present application will be described below through an embodiment:

[0062] As shown in Figure 1 and Figure 2 In this embodiment, the hydrophobic membrane 23 is selected from a PTFE (polytetrafluoroethylene) hydrophobic membrane.

[0063] The flange top plate 11, the annular sealing plate 12 and the flange bottom plate 13 are made of acrylic material, which has the advantages of low cost, convenient installation and high machining precision.

[0064] The hygroscopic hydrogel 31 is a calcium chloride-polyacrylamide hydrogel, which uses acrylamide (AM), methylene bisacrylamide (MBA), ammonium persulfate ((NH4)2S2O8) and anhydrous calcium chloride (CaCl2) as raw materials. Among them, acrylamide is used as a high polymer chain monomer, methylene bisacrylamide is used as a chemical crosslinking agent, ammonium persulfate is used as a monomer initiator, and anhydrous calcium chloride has strong hydrophilicity and can significantly increase the hygroscopic performance of the hydrogel. The specific production process is as follows: 4.264g of acrylamide and 0.027g of methylene bisacrylamide are weighed respectively, 30ml of deionized water and 19.139g of anhydrous calcium chloride are added, stirred uniformly, and the solution is cooled to room temperature (calcium chloride releases a large amount of heat when dissolved), then 0.079g of ammonium persulfate is added and stirred uniformly. Pour the prepared solution into a circular mold, then put the mold into a transparent closed container and irradiate it with a UV lamp, and introduce nitrogen as a protective gas, and after 30 minutes, the gel can be formed.

[0065] The photocatalytic layer 22 is a mixture of platinum (Pt), titanium dioxide (TiO2) and methanol (CH3OH). Hydrogen chloride platinum (H2PtCl6), titanium dioxide (TiO2) and methanol (CH3OH) are used as raw materials, wherein titanium dioxide (TiO2) is a catalyst, platinum (Pt) is a cocatalyst, the active site is increased to enhance the catalytic effect, and methanol (CH3OH) is a sacrificial agent that can inhibit the oxidation half-reaction of water splitting. The body manufacturing process is as follows: take 100mg of hydrogen chloride platinum, add 50ml of deionized water, and stir to prepare a 2mg / ml hydrogen chloride platinum solution, then add 1g of titanium dioxide and an appropriate amount of 5% volume fraction of anhydrous methanol to form a uniform mixed solution. The prepared solution is stirred with a magnetic stirrer for 2 hours, and at the same time, a solar simulator is used to irradiate at an intensity of 1000-2000W / m 2 The solution is observed to change from milky white to gray after about 1.5 hours of irradiation. Then the uniformly stirred solution is filtered with a vacuum filter, and anhydrous ethanol (CH3CH2OH) and deionized water (deionized water is added in the last filtration) are alternately added to remove all unreacted methanol in the solution. The filtered solution is added to a beaker and placed in an oven at 70°C for drying treatment to obtain a solid powder catalyst, and then the solid powder catalyst is evenly spread in the reaction tank to form the photocatalytic layer 22.

[0066] First, the protective gas inlet pipe 52 and the protective gas outlet pipe 53 are connected through the quick-acting valve 51, the air in the cavity composed of the annular sealing plate 12, the flange top plate 11 and the flange bottom plate 13 is exhausted, and the protective gas nitrogen (N2) is introduced, then the solar simulator is used to irradiate the center of the flange top plate 11, the moisture in the hygroscopic hydrogel 31 will undergo phase change evaporation at the interface of the hydrophobic film 23, due to the presence of the hydrophobic film 23, the liquid water is intercepted at the bottom surface of the hydrophobic film 23, and the water vapor migrates through the hydrophobic film 23 to contact the photocatalytic layer 22 in the catalytic reaction tank, due to the photoelectric property of the semiconductor titanium dioxide (TiO2), the water molecules undergo a splitting reaction to generate hydrogen.

[0067] Compared with the prior art, the present application has the following innovations:

[0068] 1. The present application is a photocatalytic water vapor hydrogen production device based on hygroscopic hydrogel air water extraction, the traditional photocatalytic hydrogen production catalytic reaction target is liquid water, and in the present application, the target object of photocatalytic reaction is water vapor, which provides a model with reference significance for developing efficient and clean energy.

[0069] 2. The present application considers that in arid areas, fresh water resources are scarce, and it is difficult to supplement water in time during photocatalytic hydrogen production, and innovatively uses hygroscopic hydrogel as a water extraction device. The hygroscopic hydrogel can directly absorb water from the air for use as a water source, compared with traditional photocatalytic hydrogen production, no additional water source is needed for water supplement.

[0070] 3. This invention cleverly couples the air-to-water device with the photocatalytic reaction using a hydrophobic membrane. By using interfacial catalysis, it can solve the problems of catalyst deposition and low catalytic temperature in traditional large water bodies, greatly improving the overall energy utilization efficiency of solar energy and providing a new approach for developing environmentally friendly and energy-saving hydrogen production devices.

[0071] In this application, Figure 3 , Figure 5 , Figure 7 The horizontal axis represents time, and the vertical axis represents hydrogen production. Figure 4 and Figure 6 The horizontal axis represents time, and the vertical axis represents changes in hydrogen production and water mass in the hydrogel. Figure 4 This includes solar-powered desorption photocatalytic hydrogen production and hygroscopic hydrogel-based air-to-water regeneration processes. Figure 6 This includes four solar-powered desorption photocatalytic hydrogen production processes and a hygroscopic hydrogel air-to-water regeneration process. Figure 3 The black boxes in the text represent large-scale water volume catalytic hydrogen production in the prior art, while the black circles represent interfacial photocatalytic hydrogen production in this application. Figure 4 The black boxes in the diagram represent hydrogen production, and the black lines represent changes in hydrogen mass. Figure 5 The black hexagon in the image represents 1200W / m 2 Hydrogen production under light intensity, the black circle indicates 1000 W / m 2 Hydrogen production under light intensity, the black triangle represents 800 W / m 2 Hydrogen production under light intensity; Figure 6 The black circles in the diagram represent hydrogen production, and the black lines represent changes in the mass of water in the hydrogel. Figure 7 The black circles in the diagram represent hydrogen production.

[0072] like Figure 3 As shown, compared to large-scale water-based catalysis, the hydrogen production using interfacial photocatalysis in this invention is greater; for example... Figure 4 and Figure 6 As shown, under sunlight during the day, hydrogen production gradually increases, and the water content in the hydrogel gradually decreases. At night, when there is no sunlight, the hydrogel absorbs moisture from the air, and the water content gradually increases. Figure 5 As shown, under the same time conditions, the greater the light intensity, the higher the hydrogen production; as Figure 7 As shown, in a real outdoor hydrogen production experiment, the hydrogen production increased continuously over time.

[0073] In the description of the application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0074] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0075] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0076] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0077] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0078] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and are not to be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A photocatalytic water vapor hydrogen generation device based on air water taking of a hygroscopic hydrogel, characterized in that, Include: Gas collection mechanism (1), interface catalytic reaction mechanism (2), air water collection mechanism (3), sealing mechanism (4) and exhaust sampling mechanism (5), the interface catalytic reaction mechanism (2) and the air water collection mechanism (3) are arranged inside the gas collection mechanism (1), the interface catalytic reaction mechanism (2) is arranged above the air water collection mechanism (3), the exhaust sampling mechanism (5) is arranged on the gas collection mechanism (1), the sealing mechanism (4) is arranged inside the gas collection mechanism (1) and is connected with the gas collection mechanism (1); The gas collection mechanism (1) comprises: flange top plate (11), annular sealing plate (12) and flange bottom plate (13), the flange top plate (11) and the flange bottom plate (13) are connected with the top end and the bottom end of the annular sealing plate (12) one by one, the interface catalytic reaction mechanism (2) is arranged between the flange top plate (11) and the annular sealing plate (12), and the air water collection mechanism (3) is arranged between the flange bottom plate (13) and the annular sealing plate (12); The exhaust sampling mechanism (5) comprises: two quick coupling valves (51), protective gas inlet pipe (52), protective gas outlet pipe (53), sealing rubber plug (54) and sampling needle (55), the quick coupling valve (51) is arranged through the side wall of the annular sealing plate (12), the ends of the two quick coupling valves (51) away from the annular sealing plate (12) are connected with the protective gas inlet pipe (52) and the protective gas outlet pipe (53) one by one, the sealing rubber plug (54) is sealingly connected with the through hole on the side wall of the annular sealing plate (12), and the sampling needle (55) is detachably penetrated through the sealing rubber plug (54).

2. The photocatalytic hydrogen production device from water vapor based on the air water taking of the hygroscopic hydrogel according to claim 1, characterized in that, The quartz glass is embedded in the middle of the flange top plate (11), the first annular groove is arranged at the bottom end of the flange top plate (11), the quartz glass is arranged in the first annular groove, and the circular groove and the second annular groove are arranged in the middle of the top end of the flange bottom plate (13).

3. The photocatalytic hydrogen production device from water vapor based on the hygroscopic hydrogel air water extractor according to claim 2, characterized in that, The air water collection mechanism (3) comprises: hygroscopic hydrogel (31) and object carrier (32), the object carrier (32) is a plate-shaped structure which is adaptively installed in the circular groove of the flange bottom plate (13) and is provided with a groove in the middle of the top end, and the hygroscopic hydrogel (31) is adaptively installed in the groove in the middle of the top end of the object carrier (32).

4. The photocatalytic hydrogen production device from water vapor based on the air water collector of the hygroscopic hydrogel according to claim 3, characterized in that, The hygroscopic hydrogel (31) is a composite hydrogel formed by mixing hygroscopic salt with a mass fraction of 30%-45% and hydrophilic high molecular polymer.

5. The photocatalytic hydrogen production device from water vapor based on the hygroscopic hydrogel air water extractor according to claim 2, characterized in that, The sealing mechanism (4) comprises a plurality of fastening bolts (41), two sealing washers (42) and a plurality of nuts (43), the two sealing washers (42) are one-to-one correspondingly fitted and installed in the first annular groove and the second annular groove, the plurality of fastening bolts (41) are arranged around the annular sealing plate (12), the plurality of fastening bolts (41) penetrate the flange top plate (11) and the annular sealing plate (12), and are one-to-one correspondingly screwed with the plurality of nuts (43).

6. The photocatalytic hydrogen production device from water vapor based on the air water collector using the hygroscopic hydrogel according to claim 1, characterized in that, The interface catalytic reaction mechanism (2) comprises an annular washer (21), a photocatalytic layer (22) and a hydrophobic membrane (23), the annular washer (21) and the hydrophobic membrane (23) have the same outer diameter, the annular washer (21) is sealingly installed on the hydrophobic membrane (23), and the photocatalytic layer (22) is fitted and installed in a catalytic reaction groove composed of the annular washer (21) and the hydrophobic membrane (23).

7. The photocatalytic hydrogen production device from water vapor based on the hygroscopic hydrogel air water extractor according to claim 6, characterized in that, The photocatalytic layer (22) is a powdery solid formed by mixing a photocatalyst, a sacrificial agent and a promoter.

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