A device for the electro-reduction of carbon dioxide coupled with a gradient electrode and a spiral flow channel

Abstract

The utility model discloses a kind of carbon dioxide electro-reduction devices of gradient electrode coupling spiral flow channel, including flow channel plate and electrode assembly, electrode assembly is located in flow channel plate;Reverse spiral flow channel is equipped in flow channel plate;Electrode assembly is diffusion layer, conductive layer and catalytic layer in turn by vertical stacking and interface mutual embedding mode, the aperture of diffusion layer to catalytic layer is gradient distribution, and gradually reduce, and conductive layer is located at the top of catalytic layer, and diffusion layer is located at top;Diffusion layer surface is equipped with fiber mesh structure, and conductive layer is embedded with vertically arranged carbon nanotube, and the surface of catalytic layer is dendritic catalyst;Fiber mesh structure part is pricked into conductive layer, and carbon nanotube of conductive layer is embedded into catalytic layer.This kind of device can be matched by aperture gradient and flow channel geometric parameter, break through mass transfer-reaction coupling bottleneck;Modular design reduces equipment operation and maintenance cost, and is suitable for large-scale application.

Description

Technical Field

[0001] This utility model relates to the field of electrochemical energy technology, specifically a carbon dioxide electroreduction device with gradient electrode coupled to a spiral flow channel. Background Technology

[0002] A carbon dioxide electroreduction reaction (CO2RR) device is a technology that uses an electrochemical reaction to reduce carbon dioxide (CO2) into valuable chemicals or fuels. CO2 electroreduction technology is not only part of carbon capture and utilization (CCU), but also a potential solution for addressing global climate change, reducing greenhouse gas emissions, and utilizing renewable energy. The CO2 electroreduction reaction device based on a multi-layer gradient electrode is a highly efficient carbon dioxide conversion technology for reducing carbon dioxide into useful chemicals or fuels. The key to this device design lies in optimizing the efficiency, selectivity, and stability of the reaction through a multi-layer gradient electrode structure.

[0003] Existing electrode structures are limited: Traditional gas diffusion electrodes (GDEs) have uniform porosity distribution, leading to an imbalance between CO2 gas transport and electrolyte wetting, and limiting the three-phase reaction interface; low mass transfer efficiency: The traditional flow path design of CO2 gas and electrolyte in the flow channel plate is prone to concentration polarization, reducing current density; low catalyst utilization: The planar electrode structure leads to a mismatch between the catalyst layer thickness and the exposure of active sites, resulting in poor stability.

[0004] Therefore, a solution is needed. Utility Model Content

[0005] (a) Technical problems to be solved

[0006] To address the shortcomings of existing technologies, this invention provides a carbon dioxide electroreduction device with gradient electrode coupling to a spiral flow channel, thereby solving the problems mentioned in the background section.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, this utility model provides the following technical solution: a carbon dioxide electroreduction device with gradient electrode coupling spiral flow channel, comprising a flow channel plate and an electrode assembly, wherein the electrode assembly is located within the flow channel plate; the flow channel plate is provided with a reverse spiral flow channel; the electrode assembly is arranged in sequence as a diffusion layer, a conductive layer, and a catalytic layer through vertical stacking and interlocking interfaces, wherein the pore size of the diffusion layer to the catalytic layer is gradient-distributed and decreases progressively, the conductive layer is located at the top of the catalytic layer, and the diffusion layer is located at the top; the surface of the diffusion layer is provided with a fibrous mesh structure, the conductive layer is embedded with vertically arranged carbon nanotubes, and the surface of the catalytic layer is a dendritic catalyst; the fibrous mesh structure partially penetrates the conductive layer, and the carbon nanotubes of the conductive layer are embedded in the catalytic layer.

[0009] Preferably, the spiral flow channel of the flow channel plate has a toothed rough surface, and the spiral flow channel is provided with inclined guide plates arranged alternately at intervals of 1 / 4 to 1 / 3 of the spiral cycle. The guide plates are inclined at 40-60° with the central axis of the flow channel, and the inclination directions of adjacent guide plates alternate to form a zigzag flow path.

[0010] Preferably, the guide plate has honeycomb-shaped through holes on its surface.

[0011] Preferably, a slot for cooperating with the electrode assembly is provided on one side edge of the flow channel plate. The slot has a T-shaped structure and an elastic rubber pad is provided on the inner side of the slot.

[0012] Preferably, the electrode assembly has a flange extending from its edge, which matches the slot.

[0013] (III) Beneficial Effects

[0014] This invention provides a carbon dioxide electroreduction device with a gradient electrode coupled to a spiral flow channel. It has the following advantages:

[0015] In this solution, a carbon dioxide electroreduction device with gradient electrode coupled spiral flow channel overcomes the mass transfer-reaction coupling bottleneck by matching the pore gradient with the flow channel geometric parameters; the modular design reduces equipment operation and maintenance costs and is suitable for large-scale applications. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the overall structure of the device of this utility model;

[0017] Figure 2 This is a schematic diagram of the spiral flow channel and guide plate of the cathode plate and anode plate of this utility model;

[0018] Figure 3 This is a schematic diagram of the guide plate structure of this utility model.

[0019] In the figure, 1 is the flow channel plate; 101 is the spiral flow channel; 102 is the guide plate; 2 is the electrode assembly; 201 is the diffusion layer; 202 is the conductive layer; 203 is the catalyst layer; 211 is the fibrous mesh structure; 212 is the carbon nanotube; 213 is the dendritic catalyst; 3 is the elastic rubber pad; 4 is the flange; 5 is the honeycomb through-hole; and 6 is the slot. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Please see Figure 1-3 This utility model provides a technical solution:

[0022] Example 1

[0023] To address the aforementioned problems: existing electrode structures are simplistic: traditional gas diffusion electrodes (GDEs) have uniform porosity distribution, leading to an imbalance between CO2 gas transport and electrolyte wetting, and limiting the three-phase reaction interface; mass transfer efficiency is low: the traditional flow path design of CO2 gas and electrolyte in the flow channel plate easily leads to concentration polarization, reducing current density; catalyst utilization is low: the planar electrode structure results in a mismatch between catalyst layer thickness and active site exposure, leading to poor stability.

[0024] The solution is as follows: A carbon dioxide electroreduction device with gradient electrode coupling spiral flow channel includes a flow channel plate 1 and an electrode assembly 2, wherein the electrode assembly 2 is located within the flow channel plate 1; the cathode chamber and anode chamber within the flow channel plate 1 adopt a reverse spiral flow channel 101; the electrode assembly 2 consists of a diffusion layer 201, a conductive layer 202, and a catalyst layer 203 in sequence through vertical stacking and interlocking of interfaces, wherein the pore size of the diffusion layer 201 to the catalyst layer 203 is gradient-distributed and decreases stepwise, the conductive layer 202 is located on top of the catalyst layer 203, and the diffusion layer 201 is located on top; the surface of the diffusion layer 201 is provided with a fibrous mesh structure 211, the conductive layer 202 is embedded with vertically arranged carbon nanotubes 212, and the surface of the catalyst layer 203 is a dendritic catalyst 213; the fibrous mesh structure 211 partially penetrates the conductive layer 202, and the carbon nanotubes 212 of the conductive layer 202 are embedded in the catalyst layer 203.

[0025] Analysis of the above content: Diffusion layer 201 (top layer): It is made of hydrophobic carbon cloth (PTFE treatment), with a thickness of 0.3-0.8mm, porosity of 70-90%, pore size of 10-50μm, and a loose fiber mesh structure 211 on the surface. CO2 gas enters from the top and diffuses rapidly to the lower layer, thus promoting CO2 gas diffusion.

[0026] Conductive layer 202 (intermediate layer): Graphene-modified carbon paper is used as the graphene / carbon paper composite layer with a thickness of 0.1-0.3 mm; porosity of 40-50% and pore size of 1-5 μm; vertically arranged carbon nanotubes 212 are embedded in the layer to optimize electronic conduction; and a continuous conductive path is formed by interlocking with some fibers in the diffusion layer through a hot pressing process.

[0027] Catalytic layer 203 (bottom layer): Nanoporous metal (such as Ag, Cu) is supported on a carbon fiber substrate with a thickness of 0.05-0.2 mm; porosity of 60-80% and nanoscale pore size of 50-200 nm. The surface is covered with dense dendritic catalyst 213 to increase the density of active sites. The catalytic layer 203 and the conductive layer 202 are bonded by ionic liquid to ensure electronic conduction and mechanical stability.

[0028] Gradient pore size distribution: The thickness and pore size of each layer decrease in a stepwise manner (diffusion layer 201 → conductive layer 202 → catalyst layer 203), that is, the pore size decreases stepwise from diffusion layer 201 to catalyst layer 203; the fibrous network structure 211 of diffusion layer 201 penetrates into conductive layer 202 (depth of about 20-50μm), and the carbon nanotubes 212 of conductive layer 202 are embedded in catalyst layer 203 (depth of about 5-10μm), so as to achieve dynamic balance at the gas-electrolyte-catalyst interface.

[0029] Example 2:

[0030] Please see Figure 1-3 Based on Embodiment 1, this utility model provides a technical solution: the spiral flow channel 101 of the flow channel plate 1 has a toothed rough surface, and the spiral flow channel 101 is provided with inclined guide plates 102 arranged alternately at intervals of 1 / 4 to 1 / 3 of the spiral cycle. The guide plates 102 are inclined at 40-60° with the central axis of the flow channel, and the inclination directions of adjacent guide plates 102 alternate with each other to form a zigzag flow path.

[0031] Analysis of the above content: Double helical flow channel 101: The cathode chamber and anode chamber adopt reverse helical flow channels 101. The cathode (anode) flow channel is clockwise (counterclockwise) helical, with a pitch = flow channel width × 1.2 and a depth of 0.5 mm; the anode (cathode) flow channel is counterclockwise (clockwise) helical, with a pitch = flow channel width × 1.5 and a depth of 1 mm; the inner wall of the helical flow channel 101 is a serrated rough surface (Ra = 10-20 μm). Through centrifugal force, the turbulence is enhanced, the residence time of CO2 gas is extended by 20%-30%, and the cross-section of the flow channel at the location of the guide plate 102 is reduced by 30%, forming a local high-speed zone.

[0032] Example 3:

[0033] Please see Figure 1-3 Based on Embodiment 1, this utility model provides a technical solution: the guide plate 102 has honeycomb-shaped through holes 5 on its surface.

[0034] Analysis of the above: The plate surface has honeycomb-shaped through holes 5 (1mm in diameter). These through holes 5 promote bubble breakage and accelerate liquid phase renewal, reduce bubble accumulation, and improve the local mass transfer coefficient. The inclined guide plate 102 forces the fluid to generate centrifugal vortices, prolonging the CO2 residence time.

[0035] Example 4:

[0036] Please see Figure 1-3 The present invention provides a technical solution based on Embodiment 1: a slot 6 that cooperates with the electrode assembly 2 is provided on one side edge of the flow channel plate 1. The slot 6 has a T-shaped structure and an elastic rubber pad 3 is provided on the inner side of the slot 6.

[0037] Analysis of the above: The flow channel plate 1 has a T-shaped groove 6 with a width of 2mm and a depth of 1.5mm on its edge; the inner side of the groove 6 is provided with an annular elastic rubber pad 3 (hardness Shore A 50) with a pre-compression amount of 30%.

[0038] Example 5:

[0039] Please see Figure 1-3 Based on Embodiment 1, this utility model provides a technical solution: the electrode assembly 2 has a flange 4 extending from its edge, which matches the slot 6.

[0040] Analysis of the above content: The electrode assembly 2 extends a 1.2mm thick polytetrafluoroethylene flange from its edge, which matches the T-shaped slot 6; the housing is subjected to a pressure of 5-10MPa by bolts, so that the flange 4 presses against the sealing gasket, and the pressure sensor provides real-time feedback on the contact status.

[0041] The active area of ​​electrode assembly 2 is precisely aligned with the central area of ​​spiral flow channel 101 (error ≤ 0.1 mm); the distance between the electrode surface and the bottom surface of the flow channel is 0.05-0.1 mm, and micro-bumps are used for support to prevent surface blockage.

[0042] Modular assembly: Electrode assembly 2 can be pushed laterally into flow channel plate 1 along slot 6, and a seal is formed after the bolts are tightened; the sealing ring expands evenly in all directions under pressure, filling the gap between the electrode and the flow channel plate. Distributed pressure regulation: Multiple pressure sensors can be set on the outer shell of flow channel plate 1 to adjust the sealing pressure in real time and prevent electrode deformation.

[0043] To further demonstrate the novelty and authenticity of this scheme, the following data is provided: I. Technical effect data of the gradient electrode structure

[0044]

[0045] II. Technical Performance Data of Helical Flow Channel Design

[0046]

[0047]

[0048] III. Technical Performance Data of Modular Design

[0049]

[0050] IV. Overall Performance Comparison Table

[0051]

[0052] Data Description

[0053] 1. Experimental conditions: All data were measured using 0.1M KHCO3 electrolyte, 25℃, 1atm CO2 atmosphere, and constant potential of -0.8V (vs RHE).

[0054] 2. Data source: The above data are all quantitative values ​​obtained from testing and practical applications.

[0055] 3. Technical relevance: Matching the aperture gradient with the turbulence parameters of the flow channel reduces mass transfer resistance, thereby achieving a simultaneous increase in current density and selectivity. Modular design improves engineering applicability by reducing contact resistance and maintenance costs.

[0056] These data can be directly used to support the technical effects of this solution, such as "breaking through the bottleneck of mass transfer-reaction coupling" and "being suitable for large-scale applications", and quantitatively demonstrate the creativity of this solution.

[0057] The present invention comprises: 1. a flow channel plate; 101. a spiral flow channel; 102. a guide plate; 2. an electrode assembly; 201. a diffusion layer; 202. a conductive layer; 203. a catalytic layer; 211. a fibrous mesh structure; 212. a carbon nanotube; 213. a dendritic catalyst; 3. an elastic rubber pad; 4. a flange; 5. a honeycomb through-hole; and 6. a slot. All components are general-purpose standard parts or parts known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods. The problem solved by this invention is the single-structured electrode of existing systems: traditional gas... The uniform porosity distribution of the diffusion electrode (GDE) leads to an imbalance between CO2 gas transport and electrolyte wetting, restricting the three-phase reaction interface; low mass transfer efficiency: the traditional flow path design of CO2 gas and electrolyte in the flow channel plate easily leads to concentration polarization, reducing current density; low catalyst utilization: the planar electrode structure causes a mismatch between catalyst layer thickness and active site exposure, resulting in poor stability. This invention, through the combination of the above components, can overcome the bottleneck of mass transfer-reaction coupling by matching the pore gradient with the flow channel geometry parameters; the modular design reduces equipment operation and maintenance costs and is suitable for large-scale applications.

[0058] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It will be apparent to those skilled in the art that this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0059] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A carbon dioxide electroreduction device with gradient electrode coupled to a spiral flow channel, characterized in that: It includes a flow channel plate (1) and an electrode assembly (2), wherein the electrode assembly (2) is located within the flow channel plate (1); The flow channel plate (1) is provided with a reverse spiral flow channel (101). The electrode assembly (2) consists of a diffusion layer (201), a conductive layer (202), and a catalytic layer (203) arranged in a vertical stacking and interlocking manner. The pore size of the diffusion layer (201) to the catalytic layer (203) is distributed in a gradient and decreases step by step. The conductive layer (202) is located on top of the catalytic layer (203), and the diffusion layer (201) is located on top. The diffusion layer (201) has a fibrous mesh structure (211) on its surface, the conductive layer (202) is embedded with vertically arranged carbon nanotubes (212), and the catalytic layer (203) has a dendritic catalyst (213) on its surface. The fiber mesh structure (211) partially pierces the conductive layer (202), and the carbon nanotubes (212) of the conductive layer (202) are embedded in the catalytic layer (203).

2. The carbon dioxide electroreduction device with gradient electrode coupled spiral flow channel according to claim 1, characterized in that: The spiral flow channel (101) of the flow channel plate (1) has a toothed rough surface. The spiral flow channel (101) is provided with inclined guide plates (102) arranged alternately at intervals of 1 / 4 to 1 / 3 of the spiral cycle. The guide plates (102) are inclined at 40-60° to the central axis of the flow channel. The inclination directions of adjacent guide plates (102) alternate with each other to form a zigzag flow path.

3. The carbon dioxide electroreduction device with gradient electrode coupled spiral flow channel according to claim 2, characterized in that: The guide plate (102) has honeycomb-shaped through holes (5) on its surface.

4. The carbon dioxide electroreduction device with gradient electrode coupled spiral flow channel according to claim 1, characterized in that: The flow channel plate (1) has a slot (6) on one side edge that cooperates with the electrode assembly (2). The slot (6) has a T-shaped structure and an elastic rubber pad (3) is provided inside the slot (6).

5. The carbon dioxide electroreduction device with gradient electrode coupled spiral flow channel according to claim 1, characterized in that: The electrode assembly (2) has a flange (4) extending from its edge, which matches the slot (6).

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