Spatial proton exchange membrane electrolysis cell with porous graphene microchannel structure

Abstract

The application provides a space proton exchange membrane electrolytic cell with a porous graphene micro-channel structure, and belongs to the technical field of space energy and hydrogen production by water electrolysis. The problems of large flow channel resistance, limited ion migration and complex structure of a large space occupation of a traditional electrolytic cell are solved. The space proton exchange membrane electrolytic cell comprises bipolar plates, a proton exchange membrane and catalyst layers. The two bipolar plates are combined to form a cavity inside. The proton exchange membrane is arranged between the contact surfaces of the two bipolar plates and divides the cavity into two chambers. Each chamber is filled with a porous graphene structure and forms two flow channels. The generated gas flows along the wall in the pores formed between the adjacent porous graphene structures. The catalyst layers are arranged on both sides of the proton exchange membrane, and each catalyst layer is connected with the porous graphene structure on the same side. The space proton exchange membrane electrolytic cell is mainly used for providing gas-liquid flow channels.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of space energy and hydrogen production by water electrolysis, and particularly relates to a space proton exchange membrane electrolytic cell with a porous graphene micro-channel structure. BACKGROUND

[0002] In special application scenarios such as aerospace and space stations, the weight of the device directly affects the economy and feasibility of the mission. The weight of traditional metal flow channels or thick carbon-based flow channels is relatively high, the mass transfer resistance of the electrolyte is relatively large, ion migration is limited, energy consumption is increased, and service life is shortened. In addition, the traditional flow channel structure is complex, occupies a large space, is not conducive to the miniaturization and integration of the electrolytic cell, and is difficult to meet the needs of modern industry for high-efficiency and compact electrolytic equipment.

[0003] As a two-dimensional single-layer honeycomb lattice material composed of carbon atoms, the carrier mobility of porous graphene is much higher than that of traditional carbon materials, and it has advantages such as high porosity, low density, and large specific surface area, which can significantly reduce ohmic loss and improve the overall efficiency of the electrolytic cell. The density is much lower than that of metal materials, which can significantly reduce the weight of the equipment and reduce the demand for pumping power, thereby saving energy consumption. In particular, in the space environment, energy saving is particularly critical and is particularly suitable for space and aerospace fields.

[0004] Through the 3D printing of the oxidized porous graphene structure technology, a porous graphene flow channel with high porosity and uniform pore size distribution can be prepared, and the mass transfer and gas discharge performance can be optimized.

[0005] Based on the above background, the application optimizes the flow channel structure and material performance, significantly improves the electrolysis efficiency and durability of the device, and realizes lightweight design at the same time. It can effectively deal with the core bottleneck in traditional design and is suitable for ground renewable energy hydrogen production scenarios and special needs of aerospace and space exploration.

[0006] In summary, the space proton exchange membrane electrolytic cell with a porous graphene micro-channel structure is proposed. SUMMARY

[0007] Therefore, the application aims to propose a space proton exchange membrane electrolytic cell with a porous graphene micro-channel structure to solve the problems of large flow channel resistance, limited ion migration, and complex structure of traditional electrolytic cells.

[0008] To achieve the above-mentioned purpose, the application adopts the following technical solutions to provide a space proton exchange membrane electrolytic cell with a porous graphene micro-channel structure, which comprises:

[0009] The two bipolar plates are combined to form a cavity inside;

[0010] A proton exchange membrane is arranged between the contact surfaces of the two bipolar plates and divides the cavity into two chambers, each of which is filled with a porous graphene structure having a continuous hierarchical pore distribution structure inside and forms two flow channels in which the generated gas diffuses along the pore walls.

[0011] A catalyst layer is covered on both sides of the proton exchange membrane, and the catalyst layer on each side is coupled with the porous graphene structure on the same side.

[0012] Further, the porous graphene structure is a three-dimensional single-layer honeycomb lattice material.

[0013] Further, the pore size of the porous graphene structure is 40-120 PPI, and the porosity is 95%.

[0014] Further, the two bipolar plates are respectively connected to the positive and negative poles of the power supply to form an anode side plate and a cathode side plate, and the flow channel corresponding to the anode side plate is an oxygen flow channel, and the flow channel corresponding to the cathode side plate is a hydrogen flow channel.

[0015] Further, the anode side plate is provided with a water inlet and an oxygen outlet, the water inlet and the oxygen outlet are communicated through the oxygen flow channel, and the cathode side plate is provided with a hydrogen outlet, and the hydrogen outlet is communicated with the hydrogen flow channel.

[0016] Further, the water inlet and the oxygen outlet are located on the same side of the anode side plate.

[0017] Further, the water inlet and the oxygen outlet are centrally symmetric with the center of the anode side plate.

[0018] Further, the hydrogen outlet and the oxygen outlet are symmetrically arranged with the proton exchange membrane as the symmetric surface.

[0019] Further, the hydrogen flow channel and the oxygen flow channel are symmetrically arranged with the proton exchange membrane as the symmetric surface.

[0020] Further, the anode side plate, the cathode side plate, the proton exchange membrane and the catalyst layer are sealingly arranged.

[0021] Beneficial effects:

[0022] 1. The three-dimensional structure of the porous material has a pore size of several microns to tens of microns, and under the condition of specific porosity and open porosity, the whole has good hydrophilicity and water absorption, and also has good electrical conductivity and thermal conductivity. When water contacts the material, it can be instantly absorbed by the "capillary phenomenon" and diffused along the surface between the micropores to the inside of the porous material structure, reducing the mass transfer resistance and solving the problem of limited ion migration.

[0023] Due to the lightweight design and high efficiency characteristics of the graphene material, the overall manufacturing and operating costs of the device are reduced, which is suitable for special application scenarios such as aerospace, space station, etc. BRIEF DESCRIPTION OF DRAWINGS

[0024] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and the illustrative embodiments of the present application and their description serve the purpose of explaining the present application. The accompanying drawings do not constitute an inappropriate limitation on the present application. In the drawings:

[0025] Figure 1 The overall structure schematic diagram of the space proton exchange membrane electrolysis cell of the porous graphene micro-channel structure according to the present application;

[0026] Figure 2 The exploded view of the flow channel of the space proton exchange membrane electrolysis cell of the porous graphene micro-channel structure according to the present application;

[0027] Figure 3 The graphene porous flow channel polar plate and membrane electrode assembly assembly structure schematic diagram of the space proton exchange membrane electrolysis cell of the porous graphene micro-channel structure according to the present application;

[0028] Figure 4 The porous graphene micro-channel manufacturing process schematic diagram of the space proton exchange membrane electrolysis cell of the porous graphene micro-channel structure according to the present application.

[0029] In the figure: oxygen outlet 1; water inlet 2; anode catalyst layer 3; proton exchange membrane 4; cathode catalyst layer 5; hydrogen outlet 6; hydrogen flow channel 7A; oxygen flow channel 7B; power supply 8; inlet straight groove part 9A; outlet straight groove part 9B; cathode side polar plate 10A; anode side polar plate 10B. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0031] It should be noted that the description of "left", "right", "left side", "right side", "upper part", "lower part", "top", "bottom" and the like in the present application are defined based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the described structure must be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the present application. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0032] In the description of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of two elements. 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.

[0033] Referring to the accompanying drawings, a spatial proton exchange membrane electrolytic cell with a porous graphene micro-channel structure is provided, comprising:

[0034] A bipolar plate 10, two said bipolar plates 10 are combined to form a cavity inside;

[0035] A proton exchange membrane 4 is arranged between the contact surfaces of the two said bipolar plates 10, and divides the said cavity into two chambers, each said chamber is filled with a porous graphene structure and forms two flow channels, the said porous graphene structure has a continuous hierarchical pore distribution structure inside, and the generated gas diffuses along the wall surface of the pores in the said flow channels;

[0036] A catalyst layer is covered on both sides of the proton exchange membrane 4, and each said catalyst layer on one side is coupled with the porous graphene structure on the same side.

[0037] Deionized water enters the flow channel, generates oxygen and hydrogen in the catalyst layer, and the two said flow channels adjacent to each other do not directly contact, and the gas flows along the wall surface in the pores formed by the skeleton between the two said porous graphene structures; When the reaction gas passes through the flow channel of the porous graphene, it diffuses in the horizontal and vertical directions and perpendicular to the membrane electrode direction, thereby effectively improving the uniformity of the reaction gas distribution and improving the drainage and exhaust effect of the flow channel.

[0038] In this embodiment, the said porous graphene structure is a three-dimensional single-layer honeycomb lattice material.

[0039] The flow channel is a porous graphene flow channel, which is composed of the wall surface of the porous graphene medium, and the said porous graphene material has a three-dimensional structure with a pore size of several microns to several tens of microns.

[0040] In this embodiment, the said porous graphene structure has a pore size of 40 ~ 120 PPI and a porosity of 95%.

[0041] In this embodiment, the two said bipolar plates 10 are respectively connected with the positive and negative electrodes of the power supply 8 to form an anode side plate 10B and a cathode side plate 10A, and the flow channel corresponding to the said anode side plate 10B is an oxygen flow channel 7B, and the flow channel corresponding to the cathode side plate 10A is a hydrogen flow channel 7A.

[0042] In the embodiment, the anode-side polar plate 10B is provided with a water inlet 2 and an oxygen outlet 1, the water inlet 2 and the oxygen outlet 1 are communicated through the oxygen flow channel 7B, the cathode-side polar plate 10A is provided with a hydrogen outlet 6, the hydrogen outlet 6 is communicated with the hydrogen flow channel 7A.

[0043] The bipolar plate is internally provided with an inlet straight groove part 9A and an outlet straight groove part 9B. The deionized water flows into the flow channel through the inlet straight groove part 9A, and then reacts in the catalyst layer plate to generate hydrogen or oxygen and combine with the deionized water to form a gas-liquid two-phase flow. The gas-liquid two-phase flow flows out of the flow channel through the outlet straight groove part 9B. The catalyst layer includes an anode catalyst layer 3 and a cathode catalyst layer 5. The anode catalyst layer 3 is located on the side of the anode-side polar plate 10B to generate oxygen, and the cathode catalyst layer 5 is located on the side of the cathode-side polar plate 10A to generate hydrogen. The specific materials of the anode catalyst layer 3 and the cathode catalyst layer 5 can be obtained by using the prior art, and thus will not be described here.

[0044] The inlet straight groove part 9A of the anode-side polar plate 10B is communicated with the water inlet 2, and the outlet straight groove part 9B of the anode-side polar plate 10B is communicated with the oxygen outlet 1. The outlet straight groove part 9B of the cathode-side polar plate 10A is communicated with the hydrogen outlet.

[0045] In the embodiment, the water inlet 2 and the oxygen outlet 1 are located on the same side of the anode-side polar plate 10B.

[0046] In the embodiment, the water inlet 2 and the oxygen outlet 1 are centrally symmetric with the center of the anode-side polar plate 10B.

[0047] According to the shape of the bipolar plate, the water inlet 2 and the oxygen outlet 1 can be located at the farthest relative position on the anode-side polar plate 10B, thereby increasing the flow distance of the gas-liquid in the flow channel, fully contacting the deionized water with the catalyst layer, and promoting the generation of gas.

[0048] In the embodiment, the hydrogen outlet 6 and the oxygen outlet 1 are symmetrically arranged with the proton exchange membrane 4 as the symmetric surface.

[0049] Similarly, according to the shape of the bipolar plate, the hydrogen outlet 6 and the water inlet 2 form a relatively far distance, thereby increasing the flow distance of the gas-liquid in the flow channel, fully contacting the deionized water with the catalyst layer, and promoting the generation of gas.

[0050] In the embodiment, the hydrogen flow channel 7A and the oxygen flow channel 7B are symmetrically arranged with the proton exchange membrane 4 as the symmetric surface.

[0051] All the water inlets 2, oxygen outlets 1, hydrogen outlets 6, oxygen flow channels 7B and hydrogen flow channels 7A of the bipolar plate are provided with sealing grooves, which are beneficial to maintaining the relative sealing of the internal and external relative sealing.

[0052] In the embodiment, the anode side plate 10B, the cathode side plate 10A, the proton exchange membrane 4 and the catalyst layer are arranged in a sealed manner. This is conducive to maintaining the internal seal.

[0053] Deionized water flows from the water inlet 2, enters the oxygen flow channel 7B of the porous graphene material through the anode side plate 10B, and is decomposed under the catalysis of the anode catalyst layer 3 to generate oxygen and H ＋ Protons, oxygen and the remaining unreacted water are discharged from the electrolytic cell through the oxygen outlet 1, while the protons in the form of hydrated protons pass through the proton exchange membrane 4 to the cathode, where hydrogen is synthesized under the catalysis of the cathode catalyst layer 5, and then passes through the hydrogen flow channel 7A of the porous graphene material and carries a small amount of water to be discharged from the hydrogen outlet 6.

[0054] Preparation process of porous graphene material: based on the disadvantage of insufficient viscosity of pure graphene ink, the application adopts a mixed polymer 3D printing graphene method, a polymer solution (GO, SiC, etc.) is mixed with a graphite suspension to form a 3D printing ink, a certain thickness of specific pattern is printed through a nozzle, and then light treatment, heat treatment and freeze-drying steps are carried out for solidification, shape retention and porous graphene characteristics, and mechanical properties of graphene material are enhanced.

[0055] The above disclosed embodiments of the application are only used to help explain the application. The embodiments do not describe all the details, nor limit the application to the specific embodiments described. According to the content of the specification, many modifications and changes can be made. The specification selects and describes these embodiments in order to better explain the principles and practical applications of the application, so that those skilled in the art can well understand and utilize the application.

Claims

1. A porous graphene microfluidic structured spatial proton exchange membrane electrolyzer, characterized in that, include: Bipolar plate (10), the two bipolar plates (10) are combined to form a cavity inside; A proton exchange membrane (4) is disposed between the two bipolar plates (10) and divides the cavity into two chambers. Each chamber is filled with a porous graphene structure and forms a flow channel. The porous graphene structure has a continuous hierarchical pore distribution structure inside. The generated gas diffuses and flows along the wall of the pore in the flow channel. A catalyst layer covers both sides of the proton exchange membrane (4), and the catalyst layer on each side is coupled to the porous graphene structure on the same side.

2. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 1, characterized in that: The porous graphene structure is a three-dimensional single-layer honeycomb lattice material.

3. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 1, characterized in that: The porous graphene structure has a pore size of 40 to 120 PPI and a porosity of 95%.

4. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 1, characterized in that: The two bipolar plates (10) are connected to the positive and negative terminals of the power supply (8) respectively to form an anode side plate (10B) and a cathode side plate (10A). The flow channel corresponding to the anode side plate (10B) is an oxygen flow channel (7B), and the flow channel corresponding to the cathode side plate (10A) is a hydrogen flow channel (7A).

5. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 4, characterized in that: The anode side plate (10B) is provided with a water inlet (2) and an oxygen outlet (1), which are connected through the oxygen flow channel (7B). The cathode side plate (10A) is provided with a hydrogen outlet (6), which is connected to the hydrogen flow channel (7A).

6. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 5, characterized in that: The water inlet (2) and the oxygen outlet (1) are located on the same surface of the anode side plate (10B).

7. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 6, characterized in that: The water inlet (2) and oxygen outlet (1) are centrally symmetrical about the center of the anode side plate (10B).

8. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 5, characterized in that: The hydrogen outlet (6) and oxygen outlet (1) are symmetrically arranged with the proton exchange membrane (4) as the plane of symmetry.

9. The porous graphene microchannel structure spatial proton exchange membrane electrolyzer according to claim 5, characterized in that: The hydrogen flow channel (7A) and the oxygen flow channel (7B) are symmetrically arranged with the proton exchange membrane (4) as the plane of symmetry.

10. The porous graphene microchannel structure of the spatial proton exchange membrane electrolyzer according to any one of claims 5-9, characterized in that: The anode side plate (10B), cathode side plate (10A), proton exchange membrane (4) and catalyst layer are sealed together.

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