Seawater electrolysis hydrogen production device based on zero-gap membrane electrode

Abstract

The invention belongs to the related technical field of electrolytic hydrogen production, and discloses a seawater electrolysis hydrogen production device based on a zero-gap membrane electrode, the seawater electrolysis hydrogen production device comprises a membrane electrode, the membrane electrode comprises a cathode catalyst layer, an anion exchange membrane and an anode catalyst layer which are arranged in sequence, the cathode catalyst layer and the anode catalyst layer are respectively and integrally formed on the surface of the anion exchange membrane, so that the membrane electrode is of an integral structure, and the membrane electrode is in contact with an electrolyte to perform an electrolytic reaction. The cathode catalyst layer and the anode catalyst layer are respectively and integrally formed on the surface of the anion exchange membrane to form a membrane electrode close to zero clearance, and the zero-clearance membrane electrode structure can effectively reduce the internal resistance and ohmic polarization of an electrolytic cell, so that the energy consumption of an electrolytic hydrogen production reaction is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field related to hydrogen production by electrolysis, and more specifically, relates to a hydrogen production device by electrolyzing seawater based on a zero-gap membrane electrode. Background Art

[0002] As an important energy carrier, hydrogen energy has the advantages of high energy density and pollution-free combustion. It is an ideal choice to meet sustainable energy needs and achieve dual carbon goals, and plays an important role in future energy development and application. Among various means of obtaining hydrogen energy, direct electrolysis of seawater based on renewable energy has great potential. This is because the reserves of marine renewable energy such as wind energy, solar energy, and tidal energy are extremely abundant, and the reserves of marine seawater resources are also extremely abundant, accounting for about 97% of the earth's water resources. However, direct electrolysis of seawater to produce hydrogen faces a series of challenges. This is because the composition of seawater is complex, Cl - , Ca 2+ Mg 2+ Plasma will affect the electrolysis reaction and the long-term operation of the device; at the same time, the electrolysis reaction kinetics are slow, and natural seawater usually requires precious metal catalysts to have a faster decomposition rate. As a result, the direct electrolysis of seawater to produce hydrogen system has high energy consumption, high cost and poor stability.

[0003] The current conventional technology for producing hydrogen by electrolyzing seawater requires pre-treating seawater by means of impurity removal or desalination, and then electrolyzing it in an ordinary alkaline electrolyzer. However, the driving energy consumption required for the electrolysis reaction in an ordinary alkaline electrolyzer is relatively large, which further increases the energy consumption of producing hydrogen by electrolyzing seawater. At the same time, the pre-treatment of seawater requires the construction of additional plants and equipment, which increases the cost of producing hydrogen by seawater. Therefore, a completely new design of the electrolytic hydrogen production system is needed to reduce the energy consumption of hydrogen production. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides a seawater electrolysis hydrogen production device based on a zero-gap membrane electrode, which is used to solve the problem of high energy consumption of the electrolysis reaction in the existing seawater electrolysis hydrogen production electrolyzer.

[0005] To achieve the above-mentioned purpose, according to the present invention, there is provided a hydrogen production device by electrolyzing seawater based on a zero-gap membrane electrode, comprising a membrane electrode, wherein the membrane electrode comprises a cathode catalyst layer, an anion exchange membrane and an anode catalyst layer arranged in sequence, wherein the cathode catalyst layer and the anode catalyst layer are respectively integrally formed on the surface of the anion exchange membrane so that the membrane electrode is an integral structure, and the membrane electrode contacts with an electrolyte to carry out an electrolysis reaction.

[0006] The device for producing hydrogen by electrolyzing seawater based on a zero-gap membrane electrode provided by the present invention also includes an anode current collecting plate, an anode side diaphragm and a seawater chamber, wherein the anode current collecting plate is arranged on the side of the membrane electrode where the anode catalyst layer is arranged, and the seawater chamber is arranged in connection with the anode current collecting plate, and an anode channel is arranged on the anode current collecting plate, one side of the anode channel is connected to the anode catalyst layer, and the other side of the anode channel is connected to the seawater chamber, and the anode channel and the seawater chamber are separated by the anode side diaphragm, the anode channel is used to pass the electrolyte, the seawater chamber is used to pass seawater, and the anode side diaphragm is used to allow water in the seawater to penetrate into the anode channel.

[0007] According to the zero-gap membrane electrode-based seawater electrolysis hydrogen production device provided by the present invention, the air pressure in the seawater chamber is used to drive the water in the seawater to penetrate through the anode side diaphragm into the anode channel, and the air pressure provided by the seawater chamber is 0.15-5MPa.

[0008] The device for producing hydrogen by electrolyzing seawater based on a zero-gap membrane electrode provided by the present invention also includes a cathode current collecting plate, which is arranged on the side of the membrane electrode where the cathode catalyst layer is arranged, and a cathode channel is arranged on the cathode current collecting plate, which is connected to the cathode catalyst layer, and there is no electrolyte in the cathode channel.

[0009] According to the zero-gap membrane electrode-based seawater electrolysis hydrogen production device provided by the present invention, the anode channel is distributed in a serpentine or meander shape on the anode current collecting plate, and a first inlet and outlet connected to the anode channel is provided on the anode current collecting plate; the cathode channel is distributed in a serpentine or meander shape on the cathode current collecting plate, and a second inlet and outlet connected to the cathode channel is provided on the cathode current collecting plate.

[0010] The device for producing hydrogen by electrolyzing seawater based on a zero-gap membrane electrode provided by the present invention also includes a cathode gas diffusion layer and an anode gas diffusion layer, wherein the cathode gas diffusion layer is arranged in contact with the cathode catalyst layer, and the anode gas diffusion layer is arranged in contact with the anode catalyst layer.

[0011] According to the zero-gap membrane electrode-based seawater electrolysis hydrogen production device provided by the present invention, the cathode catalyst layer and the anode catalyst layer are integrally formed on the surface of the anion exchange membrane by spraying or brushing.

[0012] According to the zero-gap membrane electrode-based seawater electrolysis hydrogen production device provided by the present invention, the electrolyte is water or an alkaline solution;

[0013] And / or, the cathode catalyst layer is a non-precious metal catalyst containing one or more of the elements Cr, Mn, Fe, Co, Ni, Cu and Mo; the anode catalyst layer is a non-precious metal catalyst containing one or more of the elements Cr, Mn, Fe, Co, Ni, Cu and Mo.

[0014] According to the zero-gap membrane electrode-based seawater electrolysis hydrogen production device provided by the present invention, the anion exchange membrane is one or more of a polyarylpiperidine type anion membrane, a polysulfone type anion exchange membrane, a quaternary ammonium salt type anion membrane, an imidazolate type anion membrane and a block copolymer type anion membrane.

[0015] According to the zero-gap membrane electrode-based seawater electrolysis hydrogen production device provided by the present invention, the components of the anode-side diaphragm include one or more of cellulose acetate, polyamide, polytetrafluoroethylene and chitosan.

[0016] In general, compared with the prior art, the above technical solution conceived by the present invention provides a hydrogen production device based on electrolysis of seawater based on zero-gap membrane electrode:

[0017] 1. The cathode catalyst layer and the anode catalyst layer are formed integrally on the surface of the anion exchange membrane to form a membrane electrode with a near "zero gap". The zero-gap membrane electrode structure can effectively reduce the internal resistance and ohmic polarization of the electrolyzer, thereby reducing the energy consumption of the electrolytic hydrogen production reaction;

[0018] 2. The anode side diaphragm can filter the impurity ions in seawater, and can realize the direct electrolysis of seawater to produce hydrogen in situ, avoiding the pre-treatment process of seawater, which is conducive to reducing costs; in addition, the anode side diaphragm inhibits the Cl - , Ca 2 + Mg 2+ The negative impact of impurity ions on the catalytic layer is beneficial to ensure the activity of the catalytic layer and thus ensure the smooth progress of the reaction, reduce the reaction energy consumption, and help maintain the service life of the catalytic layer, thereby improving the stability of the electrolytic reaction;

[0019] 3. The anode channel is filled with electrolyte, while the cathode channel is free of electrolyte. The hydrogen generated by the cathode catalyst layer reaction can directly flow through the cathode channel and then be transmitted, and there is no need for a gas-liquid separation process. The hydrogen flows out without solution resistance. The hydrogen generated at the cathode catalyst layer can be transmitted immediately, which is also beneficial to increase the hydrogen transmission speed, thereby increasing the reaction speed and reducing the reaction energy consumption;

[0020] 4. Conducting OH using anion exchange membrane - And provide water or alkaline solution as electrolyte, that is, provide a local alkaline environment, which can effectively accelerate the decomposition kinetics of seawater on the surface of non-precious metals. The catalytic components used are all non-precious metals, which effectively reduces the catalyst cost;

[0021] 5. This electrolytic hydrogen production device provides a new option for expanding the scale of hydrogen production by electrolysis of seawater. -2 The potential under current density does not exceed 1.8V, and its application value is huge. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a device for producing hydrogen by electrolyzing seawater based on a zero-gap membrane electrode provided by the present invention;

[0023] Figure 2 It is a schematic diagram of the structure of the hollow anode current collecting plate and the anode gas diffusion layers and anode side diaphragms on both sides provided by the present invention;

[0024] Figure 3 The potential-time diagram of Example 1 of the present invention, wherein the test current density is 400 mA·cm -2 , test temperature 80℃;

[0025] Figure 4 This is the potential-time diagram of Example 2 of the present invention, where the test current density is 400 mA·cm -2 , test temperature 80℃;

[0026] Figure 5 This is the potential-time diagram of Example 3 of the present invention, where the test current density is 400 mA·cm -2 , test temperature 80℃;

[0027] Figure 6 This is the potential-time diagram of Comparative Example 1 of the present invention, where the test current density is 400 mA·cm -2 , test temperature 80℃;

[0028] Figure 7 This is the potential-time diagram of Comparative Example 2 of the present invention, where the test current density is 400 mA·cm -2 , test temperature 80℃;

[0029] Figure 8 This is the potential-time diagram of Comparative Example 3 of the present invention, where the test current density is 400 mA·cm -2 , test temperature 80℃;

[0030] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0031] 11-anion exchange membrane; 12-cathode catalyst layer; 13-anode catalyst layer; 2-anode gas diffusion layer; 3-anode current collecting plate; 31-anode channel; 32-second inlet and outlet; 4-anode side diaphragm; 5-seawater chamber; 51-seawater inlet and outlet; 6-cathode gas diffusion layer; 7-cathode current collecting plate; 71-first inlet and outlet. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0033] See also Figure 1 The present embodiment provides a device for producing hydrogen by electrolyzing seawater based on a zero-gap membrane electrode, the device comprising a membrane electrode, the membrane electrode comprising a cathode catalyst layer 12, an anion exchange membrane 11 and an anode catalyst layer 13 arranged in sequence, the cathode catalyst layer 12 and the anode catalyst layer 13 are respectively integrally formed on the surface of the anion exchange membrane 11 so that the membrane electrode is an integral structure, and the membrane electrode contacts the electrolyte for an electrolysis reaction.

[0034] In this embodiment, the cathode catalyst layer 12 and the anode catalyst layer 13 are integrated on the surface of the anion exchange membrane 11 to form a nearly zero-gap integrated membrane electrode. The integrated membrane electrode is contacted with the electrolyte for electrolysis reaction to obtain hydrogen and oxygen products to achieve hydrogen production. During the electrolysis process, the cathode hydrogen evolution reaction occurs in the cathode catalyst layer 12, and the anode oxygen evolution reaction occurs in the anode catalyst layer 13. The anion exchange membrane 11 transfers the electrolyte and OH - , conduction system. The water in the electrolyte comes from seawater.

[0035] This embodiment takes into account that the cathode and anode of the existing common alkaline electrolyzer are independently arranged and both have solution circulation, and the catalyst, diaphragm, current collecting plate and other structures are not tightly combined in a zero-gap manner, resulting in a large internal resistance, large ohmic polarization, and a high driving voltage, thereby requiring high electrolysis energy consumption. This embodiment proposes to set an integrated membrane electrode, and the cathode catalyst layer 12, the anion exchange membrane 11 and the anode catalyst layer 13 are matched with approximately zero gap, which is conducive to minimizing the spacing between the structural layers to the greatest extent, thereby reducing the transmembrane transmission resistance of the reactants and charges, reducing the internal resistance, and the reactants and charges can pass through the anion exchange membrane 11 from the electrode catalyst layer on one side without migration, and can immediately react with the electrode catalyst layer on the other side, which is also conducive to greatly improving the material transmission speed, which is conducive to the reaction, thereby reducing the energy consumption required for electrolysis drive, and playing a role in reducing the energy consumption of the electrolysis reaction.

[0036] Furthermore, a hydrogen production device by electrolyzing seawater based on a zero-gap membrane electrode also includes an anode current collecting plate 3, an anode side diaphragm 4 and a seawater chamber 5, wherein the anode current collecting plate 3 is arranged on the side of the membrane electrode where the anode catalyst layer 13 is arranged, and the seawater chamber 5 is arranged in connection with the anode current collecting plate 3, and an anode channel 31 is provided on the anode current collecting plate 3, one side of the anode channel 31 is connected to the anode catalyst layer 13, and the other side of the anode channel 31 is connected to the seawater chamber 5, and the anode channel 31 and the seawater chamber 5 are separated by the anode side diaphragm 4, the anode channel 31 is used to pass the electrolyte, the seawater chamber 5 is used to pass seawater, and the anode side diaphragm 4 is used to penetrate water in the seawater into the anode channel 31.

[0037] The anode current collector plate 3 is hollowed out in the middle to form an anode channel 31, which is connected to the seawater chamber 5 through the anode side diaphragm 4. The anode side diaphragm 4 prevents impurity ions in the seawater from migrating to the anode catalyst layer 13, allowing water molecules to pass through the diaphragm to supply water to the anode. The anode side diaphragm 4 is provided to separate the anode channel 31 from the seawater chamber 5 to suppress the interference of impurity ions in situ, realize the stable production of hydrogen directly using seawater, and reduce the internal polarization of the electrolyzer.

[0038] Specifically, the gas pressure in the seawater chamber 5 is used to drive the water in the seawater to penetrate through the anode side diaphragm 4 and penetrate into the anode channel 31. That is, in this embodiment, the driving force for the seawater to supply water to the anode through the anode side diaphragm 4 is the pressure difference. The anode current collector 3 is hollowed out in the middle and fits with the anode side diaphragm 4. The anode side diaphragm 4 is connected to the seawater chamber 5. Driven by the gas pressure in the seawater chamber 5, the water molecules in the seawater chamber 5 will cross the membrane and enter the anode reaction area, and Cl - , Ca 2+ Mg 2+ The impurity ions will be blocked by the anode side diaphragm 4, thereby avoiding the negative impact of the impurity ions in the seawater on the catalyst layer, and realizing the in-situ direct use of seawater to produce hydrogen. The air pressure provided by the seawater chamber is 0.15-5MPa.

[0039] Furthermore, a hydrogen production device based on zero-gap membrane electrode electrolysis of seawater also includes a cathode current collecting plate 7, which is arranged on the side of the membrane electrode where the cathode catalyst layer 12 is arranged, and a cathode channel is provided on the cathode current collecting plate 7, and the cathode channel is connected to the cathode catalyst layer 12, and there is no electrolyte in the cathode channel.

[0040] Furthermore, a zero-gap membrane electrode-based electrolysis of seawater hydrogen production device further includes a cathode gas diffusion layer 6 and an anode gas diffusion layer 2, wherein the cathode gas diffusion layer 6 is connected to the cathode catalyst layer 12, and the anode gas diffusion layer 2 is connected to the anode catalyst layer 13. The cathode gas diffusion layer 6 can be connected to the cathode catalyst layer 12 by a hot pressing process; the anode gas diffusion layer 2 can also be connected to the anode catalyst layer 13 by a hot pressing process.

[0041] In this embodiment, there is no solution input in the cathode region, and the cathode product hydrogen crosses the cathode gas diffusion layer 6 into the flow channel and then passes out. Water or alkaline aqueous solutions such as NaOH and KOH are input in the anode region, and the anode product oxygen crosses the anode gas diffusion layer 2 and is transmitted in the flow channel together with the solution. No solution is introduced into the cathode, and the reactant water molecules react directly on the membrane electrode containing the catalyst layer. The cathode outputs relatively pure hydrogen, avoiding the separation step of hydrogen and solution; at the same time, the cathode does not pass the solution, which is conducive to the rapid escape of gas products, accelerates mass transfer, reduces concentration polarization, and reduces energy consumption.

[0042] Furthermore, the cathode channel can also be set as a negative pressure channel, that is, a certain negative pressure can be formed inside the cathode channel by setting an induced draft fan to connect the cathode channel, which is beneficial to the rapid overflow of the cathode product hydrogen, thereby facilitating mass transfer, so as to further reduce concentration polarization and play a role in reducing energy consumption.

[0043] In some specific embodiments, reference Figure 2 The anode channel 31 is distributed in a serpentine or meander shape on the anode current collecting plate 3, and a first inlet and outlet 71 communicating with the anode channel 31 is provided on the anode current collecting plate 3; the cathode channel is distributed in a serpentine or meander shape on the cathode current collecting plate 7, and a second inlet and outlet 32 ​​communicating with the cathode channel is provided on the cathode current collecting plate 7.

[0044] The cathode gas inlet and outlet channel, i.e., the second inlet and outlet 32, is used to transmit and collect hydrogen, and the anode gas-liquid inlet and outlet channel, i.e., the first inlet and outlet 71, is used to transmit and collect oxygen and anode solution. Seawater is transmitted through the seawater inlet and outlet channel, i.e., the seawater inlet and outlet 51. The seawater in the electrolyzer flows through the seawater chamber 5 through the seawater inlet and outlet channel without direct contact with the catalyst layer; water or alkaline aqueous solutions such as NaOH and KOH are input into the anode region, wherein the water mainly comes from the transmembrane transmission of water molecules in the seawater, and the anode product oxygen is discharged through the anode gas-liquid inlet and outlet channel.

[0045] In some specific embodiments, the cathode catalyst layer 12 and the anode catalyst layer 13 are integrally formed on the surface of the anion exchange membrane 11 by spraying or brushing, respectively.

[0046] The cathode catalyst layer 12 and the anode catalyst layer 13 in the electrolyzer are integrally formed on the surface of the anion exchange membrane 11 to form a "zero gap" membrane electrode, the cathode gas diffusion layer 6 is bonded to the cathode catalyst layer 12, the anode gas diffusion layer 2 is bonded to the anode catalyst layer 13, and the current collecting plate with flow channels is bonded to the outside of the gas diffusion layer. The various components are combined together in a form close to zero gap, which greatly reduces the internal resistance and ohmic polarization of the electrolyzer.

[0047] In some specific embodiments, the electrolyte is water or an alkaline solution.

[0048] The cathode catalyst layer 12 is a non-precious metal catalyst containing one or more of the elements Cr, Mn, Fe, Co, Ni, Cu and Mo; the anode catalyst layer 13 is a non-precious metal catalyst containing one or more of the elements Cr, Mn, Fe, Co, Ni, Cu and Mo. Both the cathode catalyst layer 12 and the anode catalyst layer 13 do not contain precious metals.

[0049] Specifically, the anion exchange membrane 11 is one or more of a polyarylpiperidine type anion membrane, a polysulfone type anion exchange membrane 11, a quaternary ammonium salt type anion membrane, an imidazolate type anion membrane and a block copolymer type anion membrane.

[0050] The components of the anode-side separator 4 include one or more of cellulose acetate, polyamide, polytetrafluoroethylene and chitosan.

[0051] The cathode gas diffusion layer 6 is one or more of carbon paper, carbon cloth, porous nickel, and porous titanium; the anode gas diffusion layer 2 is one or more of carbon paper, carbon cloth, porous nickel, and porous titanium; the cathode current collecting plate 7 with flow channels is composed of one or more of graphite, nickel, titanium, and stainless steel; the anode current collecting plate 3 with flow channels is composed of one or more of graphite, nickel, titanium, and stainless steel.

[0052] The present embodiment of the invention discloses an electrolytic cell for producing hydrogen by direct electrolysis of seawater based on a "zero gap" membrane electrode, the structure of which includes a cathode catalyst layer 12, an anode catalyst layer 13, an anion exchange membrane 11, a cathode gas diffusion layer 6, an anode gas diffusion layer 2, a cathode gas inlet and outlet channel, i.e., a second inlet and outlet 32, an anode gas-liquid inlet and outlet channel, i.e., a first inlet and outlet 71, a cathode current collector plate 7 with a flow channel, an anode current collector plate 3 with a flow channel, an anode side diaphragm 4, a seawater chamber 5, and a seawater inlet and outlet channel, i.e., a seawater inlet and outlet 51. The anode current collector plate 3 with a flow channel is bonded to the anode gas diffusion layer 2, the anode current collector plate 3 is hollowed out in the middle and bonded to the anode side diaphragm 4, the anode side diaphragm 4 is connected to the seawater chamber 5, and the device is provided with a cathode gas inlet and outlet channel, an anode gas-liquid inlet and outlet channel, and a seawater inlet and outlet channel for material transmission.

[0053] This embodiment applies zero-gap membrane electrode technology to direct seawater electrolysis to produce hydrogen, which can effectively reduce the internal resistance and ohmic polarization of the system and reduce the energy consumption of seawater hydrogen production; at the same time, the anode side diaphragm 4 can prevent the impurity ions in the seawater from contacting the anode catalyst layer 13 while transmitting water molecules, and avoid the interference of impurity ions while using seawater to supply water to the electrolysis system. Based on this embodiment, low-energy direct seawater electrolysis to produce hydrogen can be achieved.

[0054] This embodiment 2 provides an application of an electrolytic cell in direct seawater electrolysis. The electrolytic cell, i.e., an electrolytic hydrogen production device, can directly electrolyze seawater, 400 mA·cm -2 The working potential does not exceed 1.8V under the current density, and the hydrogen and oxygen products are discharged from the cathode gas inlet and outlet channel and the anode gas-liquid inlet and outlet channel respectively.

[0055] The following are specific application examples according to the present invention. Unless otherwise specified, the raw materials in this example are purchased through commercial channels and used directly without being processed; the test conditions of the instrument adopt the parameters recommended by the manufacturer.

[0056] Example 1

[0057] A NiFe alloy is used as a cathode catalyst layer 12, a NiFe alloy is used as an anode catalyst layer 13, which is sprayed on the surface of a 5cm*5cm polyaryl piperidine type anion membrane, a 5cm*5cm carbon paper is used as a cathode gas diffusion layer 6, a 5cm*5cm porous nickel mesh is used as an anode gas diffusion layer 2, which is hot pressed on the catalyst layer surface, a cathode current collector 7 is made of graphite with a flow channel, an anode current collector 3 is made of a titanium plate with a flow channel, and an anode side diaphragm 4 is made of cellulose acetate, according to Figure 1 The electrolytic cell is assembled as shown, and the anode current collector 3 and the anode gas diffusion layers 2 on both sides and the anode side diaphragm 4 are structured as shown in FIG. Figure 2 As shown. Seawater flows in the seawater chamber 5 through the seawater inlet and outlet channels. The pressure in the chamber is 1 MPa. 1 mL of 0.2 M NaOH solution is injected into the anode channel. Then, a potential-time curve test is performed. The test current density is 400 mA cm -2 , test temperature 80℃. Figure 3 As shown, its operating voltage is 1.78V and the response is relatively stable.

[0058] Example 2

[0059] CoFe phosphide is used as the cathode catalyst layer 12, NiMo alloy nanoparticles are used as the anode catalyst layer 13, sprayed on the surface of a 3cm*3cm quaternary ammonium salt anion membrane, a 3cm*3cm porous titanium mesh is used as the cathode gas diffusion layer 6, a 3cm*3cm porous titanium mesh is used as the anode gas diffusion layer 2, hot pressed on the catalyst layer surface, the cathode current collector 7 uses graphite with a flow channel, the anode current collector 3 uses a nickel plate with a flow channel, and the anode side diaphragm 4 uses polyamide to assemble the electrolytic cell. Seawater flows in the seawater chamber 5 through the seawater inlet and outlet channels, a pressure of 5MPa is applied in the chamber, and 1mL of water is injected into the anode channel. Subsequently, a potential-time curve test is performed, and the test current density is 400mA·cm -2 , test temperature 80℃. Figure 4 As shown, at 80℃ and 400mA·cm -2 The operating voltage is 1.75V, and the response is relatively stable.

[0060] Example 3

[0061] CrCu porous alloy is used as cathode catalyst layer 12, MnFe oxide nanoparticles are used as anode catalyst layer 13, sprayed on the surface of 5cm*5cm polysulfone anion exchange membrane 11, 5cm*5cm carbon cloth is used as cathode gas diffusion layer 6, 5cm*5cm porous titanium mesh is used as anode gas diffusion layer 2, hot pressed on the catalyst layer surface, cathode current collector 7 uses titanium plate with flow channel, anode current collector 3 uses stainless steel plate with flow channel, anode side diaphragm 4 uses polytetrafluoroethylene, and assembles electrolytic cell. Seawater flows in seawater chamber 5 through seawater inlet and outlet channels, 0.2MPa pressure is applied in the chamber, and 1mL of 3% KOH solution is injected into the anode channel. Then the potential-time curve test is carried out, and the test current density is 400mA·cm -2 , test temperature 80℃. Figure 5 As shown, its operating voltage is 1.72V and the response is relatively stable.

[0062] Comparative Example 1

[0063] This comparative example provides a conventional alkaline seawater electrolysis hydrogen production electrolyzer without a zero-gap membrane electrode structure, that is, the cathode catalyst is arranged in the cathode chamber, the anode catalyst is arranged in the anode chamber, the cathode chamber and the anode chamber are separated by a diaphragm, the cathode chamber and the anode chamber are respectively filled with electrolyte, and the conventional alkaline seawater electrolysis hydrogen production electrolyzer usually arranges the cathode catalyst and the anode catalyst close to the diaphragm; Comparative Example 1 and Figure 1The difference between the structures shown is that the cathode catalyst layer 12 and the anode catalyst layer 13 are independent structures, which are arranged in close contact with the anion exchange membrane 11, and the cathode channel and the anode channel 31 are filled with electrolytes. NiFe alloy is used as the cathode and anode respectively, 0.2M NaOH is passed through the cathode and anode, and seawater is transferred to the 0.2M NaOH solution through the anode side diaphragm 4 under the pressure of 1MPa. The potential-time curve test is carried out, and the test current density is 400mA·cm -2 , test temperature 80℃. Figure 6 As shown, its operating voltage is 2.3V, which is significantly higher than the electrolytic cell designed in the present invention.

[0064] According to research, the internal resistance of the integrated membrane electrode in the zero-gap membrane electrode-based electrolysis hydrogen production device provided in the embodiment of the present invention is 70-130mR, which can reduce the internal resistance of the electrolyzer to the milliohm level; while in the conventional alkaline seawater electrolysis hydrogen production electrolyzer, the internal resistance of the catalyst and the diaphragm in which the cathode catalyst and the anode catalyst are arranged close to the diaphragm is usually at the ohm level; it can be seen that the integrated membrane electrode can reduce the internal resistance of the electrolyzer more significantly, and the consumption reduction effect is more significant.

[0065] Comparative Example 2

[0066] This comparative example provides a hydrogen production electrolyzer for electrolyzing seawater without an anode-side diaphragm 4, i.e. Figure 1 The difference between the structures shown is that there is no anode side diaphragm 4. NiFe alloy is used as cathode catalyst layer 12, NiFe alloy is used as anode catalyst layer 13, sprayed on the surface of 5cm*5cm polyaryl piperidine type anion membrane, 5cm*5cm carbon paper is used as cathode gas diffusion layer 6, 5cm*5cm porous nickel mesh is used as anode gas diffusion layer 2, hot pressed on the catalyst layer surface, cathode collector plate 7 uses graphite with flow channel, anode collector plate 3 uses titanium plate with flow channel. Seawater is directly introduced into the anode reaction area through the anode gas-liquid inlet and outlet channel, and the potential-time curve test is carried out, and the test current density is 400mA·cm -2 , test temperature 80℃. Figure 7 As shown, its working voltage is 2.2V, which is significantly higher than the electrolytic cell designed in the present invention, and the voltage required for the comparative example increases sharply after 1 hour, and the stability is poor.

[0067] Comparative Example 3

[0068] This comparative example provides a hydrogen production device for electrolyzing seawater with a zero-gap membrane electrode, but the cathode channel and the anode channel 31 are respectively filled with electrolyte. NiFe alloy is used as the cathode catalyst layer 12, NiFe alloy is used as the anode catalyst layer 13, sprayed on the surface of a 5cm*5cm polyaryl piperidine anion membrane, 5cm*5cm carbon paper is used as the cathode gas diffusion layer 6, 5cm*5cm porous nickel mesh is used as the anode gas diffusion layer 2, hot pressed on the catalyst layer surface, the cathode current collector 7 uses graphite with a flow channel, the anode current collector 3 uses a titanium plate with a flow channel, and the anode side diaphragm 4 uses cellulose acetate. Seawater flows in the seawater chamber 5 through the seawater inlet and outlet channels, the pressure in the chamber is 1MPa, 1mL of 0.2M NaOH solution is injected into the anode channel, and 0.2M NaOH solution circulates in the cathode channel. Subsequently, a potential-time curve test is carried out, and the test current density is 400mA·cm -2 , test temperature 80℃. Figure 8 As shown, its operating voltage is about 1.93V, which is higher than that of Example 1.

[0069] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydrogen production device based on zero-gap membrane electrode electrolysis of seawater, characterized in that: It includes a membrane electrode, which includes a cathode catalyst layer, an anion exchange membrane and an anode catalyst layer arranged in sequence. The cathode catalyst layer and the anode catalyst layer are respectively integrally formed on the surface of the anion exchange membrane so that the membrane electrode is an integrated structure. The membrane electrode contacts the electrolyte for electrolysis reaction.

2. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to claim 1, characterized in that: The invention also includes an anode current collecting plate, an anode side diaphragm and a seawater chamber, wherein the anode current collecting plate is arranged on a side of the membrane electrode where the anode catalyst layer is arranged, and the seawater chamber is arranged in contact with the anode current collecting plate. An anode channel is arranged on the anode current collecting plate, one side of the anode channel is connected to the anode catalyst layer, and the other side of the anode channel is connected to the seawater chamber, and the anode channel and the seawater chamber are separated by the anode side diaphragm, the anode channel is used to pass the electrolyte, the seawater chamber is used to pass seawater, and the anode side diaphragm is used to allow water in the seawater to penetrate into the anode channel.

3. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to claim 2, characterized in that: The air pressure in the seawater chamber is used to drive the water in the seawater to penetrate through the anode side diaphragm into the anode channel. The air pressure provided by the seawater chamber is 0.15-5 MPa.

4. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to claim 2, characterized in that: It also includes a cathode current collecting plate, which is arranged on a side of the membrane electrode where the cathode catalyst layer is arranged, and a cathode channel is arranged on the cathode current collecting plate, the cathode channel is connected to the cathode catalyst layer, and there is no electrolyte in the cathode channel.

5. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to claim 4, characterized in that: The anode channel is distributed in a serpentine or meander shape on the anode current collecting plate, and a first inlet and outlet communicating with the anode channel is provided on the anode current collecting plate; the cathode channel is distributed in a serpentine or meander shape on the cathode current collecting plate, and a second inlet and outlet communicating with the cathode channel is provided on the cathode current collecting plate.

6. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to any one of claims 1 to 5, characterized in that: It also includes a cathode gas diffusion layer and an anode gas diffusion layer. The cathode gas diffusion layer is arranged in contact with the cathode catalyst layer, and the anode gas diffusion layer is arranged in contact with the anode catalyst layer.

7. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to any one of claims 1 to 5, characterized in that: The cathode catalyst layer and the anode catalyst layer are integrally formed on the surface of the anion exchange membrane by spraying or brushing.

8. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to any one of claims 1 to 5, characterized in that: The electrolyte is water or alkaline solution; And / or, the cathode catalyst layer is a non-precious metal catalyst containing one or more of the elements Cr, Mn, Fe, Co, Ni, Cu and Mo; the anode catalyst layer is a non-precious metal catalyst containing one or more of the elements Cr, Mn, Fe, Co, Ni, Cu and Mo.

9. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to any one of claims 1 to 5, characterized in that: The anion exchange membrane is one or more of a polyarylpiperidine type anion exchange membrane, a polysulfone type anion exchange membrane, a quaternary ammonium salt type anion membrane, an imidazolate salt type anion membrane and a block copolymer type anion membrane.

10. The device for producing hydrogen by electrolysis of seawater based on zero-gap membrane electrode according to claim 2, characterized in that: The components of the anode-side separator include one or more of cellulose acetate, polyamide, polytetrafluoroethylene and chitosan.

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