Spiral track centrifugal spin-coating continuous UV preparation self-supporting gas diffusion electrode device

Abstract

The invention provides a spiral track centrifugal spin coating continuous UV preparation self-supporting gas diffusion electrode device. The spiral track centrifugal spin coating continuous UV preparation self-supporting gas diffusion electrode device comprises a spiral track belt and a rotary outer cylinder connected to the spiral track belt in a sleeving mode. An inner track matched with the spiral track belt is arranged in the rotary outer cylinder, a driving assembly used for driving the rotary outer cylinder to rotate in the circumferential direction is arranged on the outer wall of the rotary outer cylinder, and a plurality of electrode plates to be machined are arranged in the spiral track belt at intervals. According to the device disclosed by the invention, centrifugal force can be provided as required while continuous sample injection is carried out on the spiral track, and a catalyst precursor is more uniformly and controllably coated on the surface of the porous electrode by virtue of a centrifugal spin-coating mode.

Description

Technical Field

[0001] The invention belongs to the technical field of electrode preparation, and in particular relates to a spiral track centrifugal spin coating continuous UV preparation self-supporting gas diffusion electrode device. Background Art

[0002] Gas Diffusion Electrode (GDE) is a special porous membrane electrode. It is widely used in new energy fields such as fuel cells, water electrolysis to produce hydrogen, air batteries, carbon dioxide reduction, and nitrogen reduction due to its high activity, high selectivity, low cost, and good stability. The gas diffusion electrode is the core site for realizing electrochemical reactions for energy conversion. Complex gas-liquid-solid three-phase interface gas-phase mass transfer, liquid-phase mass transfer, and electron transfer must be carried out on it. Therefore, its structural design, catalyst selection, and preparation process will directly affect the performance and efficiency of the device.

[0003] At present, the catalysts on gas diffusion electrodes used in fuel cells and water electrolysis are mostly precious metals / metal oxides such as Pt, Ir, and Ru. First, the natural reserves of precious metals are limited, which poses a challenge to their long-term sustainable use; second, precious metals are expensive, which limits their economic feasibility in large-scale industrial applications. Therefore, the development of transition metal oxide catalysts with abundant reserves, low prices, and excellent catalytic performance has become an ideal choice.

[0004] The traditional method of preparing gas diffusion electrodes is: first synthesize or purchase the target catalyst nanopowder / particles, configure the target catalyst into a suitable slurry by adding surfactants, binders, conductive agents, etc., and then modify and coat the catalyst on porous electrodes such as carbon paper, nickel felt, titanium felt, stainless steel felt, etc. by conventional electrode preparation methods such as drop coating, spin coating, spray coating, and transfer printing to prepare gas diffusion electrodes for subsequent assembly of energy devices. It can be seen that in the method of preparing gas diffusion electrodes by slurry method, the catalyst layer and the porous diffusion layer are separated, the mass transfer resistance is large, and the adhesion between the two is poor, and the inherent defects such as shedding and peeling are prone to occur after long-term use. In order to ensure the high reaction activity area of ​​the gas diffusion electrode, nano-scale precious metal catalysts are generally used. In view of the inherent self-polymerization characteristics of nanomaterials, organic dispersants, binders, etc. need to be added during the slurry preparation process, but organic matter will cover the surface active sites of the catalyst, reducing the catalytic performance and efficiency. Self-supporting gas diffusion electrodes do not require the addition of organic dispersants and binders, which reduces factors that may reduce electrochemical performance. At the same time, the higher effective active area can provide more reaction active sites, and have sufficient strength and flexibility to maintain the wide applicability of the electrode. However, the current preparation methods (filtration film formation, freeze drying, in situ growth, etc.) are mostly suitable for laboratory preparation, and it is not possible to continuously prepare uniform and stable gas diffusion electrodes on an industrial scale. Summary of the invention

[0005] In view of this, the present invention aims to overcome the defects in the prior art and designs a spiral track centrifugal spin coating continuous UV preparation self-supporting gas diffusion electrode device.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] A spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device comprises a spiral track belt and a rotating outer cylinder sleeved on the spiral pipeline belt;

[0008] The rotating outer cylinder is provided with an inner track matched with the spiral track belt, the outer wall of the rotating outer cylinder is provided with a driving assembly for driving the rotating outer cylinder to rotate circumferentially, and a plurality of electrode sheets to be processed are arranged at intervals in the spiral track belt.

[0009] In some embodiments of the present invention, continuous spiral track grids for placing electrode sheets are arranged at intervals in sequence in the spiral track belt.

[0010] In some embodiments of the present invention, a plurality of holes are disposed at the bottom of the spiral track grid.

[0011] In some embodiments of the present invention, a conveyor belt is provided on the spiral track belt for driving the spiral track belt to generate radial movement.

[0012] In some embodiments of the present invention, the spiral track grid is sequentially separated by a plurality of partitions.

[0013] In some embodiments of the present invention, the electrode sheet entering the rotating outer cylinder is immersed in an iron-cobalt-nickel precursor solution.

[0014] In some embodiments of the present invention, a feeding device for feeding electrode sheets into the spiral track grids in the spiral track belt is provided at the inlet of the rotating outer cylinder.

[0015] In some embodiments of the present invention, a UV reaction box sleeved on a spiral track is provided downstream of the rotating outer cylinder, and a plurality of UV lamps are installed in the UV reaction box.

[0016] In some embodiments of the present invention, a plurality of UV lamps are arranged along the four sides of the UV reaction box.

[0017] In some embodiments of the present invention, a material collector sleeved on a spiral track belt is provided downstream of the UV reaction box for collecting electrode sheets that have undergone light irradiation reaction in the UV reaction box.

[0018] In some embodiments of the present invention, a plurality of collecting paddles for collecting electrode sheets in the spiral track grid are arranged in the material collector.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] (1) The spiral orbit centrifugal spin coating continuous UV self-supporting gas diffusion electrode device of the present invention can be widely used in the preparation of reaction electrodes (membrane electrodes, gas diffusion electrodes, ordered membrane electrodes, etc.) in the new energy industry (fuel cells, water electrolysis, carbon dioxide reduction, nitrogen reduction, metal air batteries, etc.);

[0021] (2) The spiral centrifugal spin coating of the present invention allows the catalyst precursor slurry such as iron, cobalt, and nickel (Fe, Co, and Ni) to be uniformly deposited and coated on a sheet electrode such as a porous / fibrous (carbon paper, nickel felt, titanium felt, stainless steel felt, ion exchange membrane, etc.), and then UV light is used to realize large-scale preparation of continuous self-supporting gas diffusion electrodes, which provides feasibility for realizing continuous industrial-grade preparation of self-supporting gas diffusion electrodes such as iron, cobalt, and nickel:

[0022] (3) The spiral track of the present invention is used for continuous UV irradiation preparation of a self-supporting gas diffusion electrode device by centrifugal spin coating. While continuously injecting samples, the spiral track can provide centrifugal force as needed, so that the catalyst precursor can be more evenly and controllably coated on the porous electrode surface by centrifugal spin coating;

[0023] (4) The UV ultraviolet irradiation preparation method adopted in the present invention is simple and easy to operate, and is easy to prepare the gas diffusion electrode on a continuous industrial scale;

[0024] (5) The UV ultraviolet light preparation adopted by the present invention does not require the use of a binder, and can directly prepare a high-performance self-supporting gas diffusion electrode;

[0025] (6) The iron-cobalt-nickel precursor solution used in the present invention is abundant and inexpensive, and the prepared amorphous oxide catalyst has the potential to replace precious metal catalysts in terms of performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 It is a schematic diagram of the overall structure of a self-supporting gas diffusion electrode device prepared by continuous UV centrifugal spin coating on a spiral track according to an embodiment of the present invention;

[0028] Figure 2 A schematic diagram of a spiral track belt in an embodiment;

[0029] Figure 3Schematic diagram of the internal structure of the spiral track belt in the embodiment.

[0030] Description of reference numerals:

[0031] 1. Rotating outer cylinder; 2. Inner track; 3. Spiral track belt; 4. Material collector; 5. Spiral track grid; 6. Partition; 7. Conveyor belt; 8. Outer cylinder gear; 9. Rotating motor; 10. Collecting paddle; 11. Feeding device; 12. Electrode sheet; 13. UV reaction box; 14. Holes. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0033] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, if there are descriptions of "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present application. In the description of the present invention, unless otherwise specified, the meaning of "multiple" is two or more.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0036] See also Figure 1-Figure 3 As shown, the present invention provides a spiral track centrifugal spin coating continuous UV preparation self-supporting gas diffusion electrode device, which uses the spiral track 2 to continuously inject samples and provide centrifugal force as needed to evenly coat the iron-cobalt-nickel precursor solution on the electrode surface by centrifugal spin coating; the subsequent UV light treatment can realize the continuous industrial-grade self-supporting gas diffusion electrode without adding binder.

[0037] The specific structure of the spiral track centrifugal spin coating continuous UV preparation self-supporting gas diffusion electrode device of the present invention includes a spiral track 2 belt and a rotating outer cylinder 1 sleeved on the spiral pipeline belt; Figure 1 As shown, the inner track 2 matched with the spiral track 2 is arranged in the rotating outer cylinder 1, and the outer wall of the rotating outer cylinder 1 is provided with a driving assembly for driving the rotating outer cylinder 1 to rotate circumferentially, and a plurality of electrode sheets 12 to be processed are arranged at intervals in the spiral track 2. The electrode sheets 12 entering the rotating outer cylinder 1 are first immersed in the iron-cobalt-nickel precursor solution, and then enter the rotating outer cylinder 1 for centrifugal spin coating.

[0038] In some embodiments of the present invention, the driving component is a rotating motor 9, the output shaft of the rotating motor 9 is connected to a driving gear, and the outer wall of the rotating outer cylinder 1 is circumferentially sleeved with an outer cylinder gear 8, which is a driven gear meshing with the driving gear.

[0039] In some embodiments of the present invention, the spiral track belt 3 is provided with continuous spiral track grids 5 for placing the electrode sheets 12 at intervals. Figure 3 As shown, a plurality of holes 14 are provided at the bottom of the spiral track grid 5. The holes 14 can be provided to discharge the excess iron-cobalt-nickel precursor solution thrown out by the rotating centrifugal action at any time.

[0040] Since the spiral track belt 3 is connected to the track 2 in the rotating outer cylinder 1, when the rotating outer cylinder 1 is driven to rotate at a uniform speed by the rotating motor 9, the spiral track belt 3 is driven by the conveyor belt 7 to produce radial forward motion and a certain axial rotation will also be generated. Under the action of the rotating centrifugal force, the iron-cobalt-nickel precursor solution impregnated on the surface and inside of the electrode sheet 12 is distributed more evenly. The uniform distribution of the iron-cobalt-nickel precursor solution can increase the number of active sites. For example, in the electrocatalytic process of electrolysis of water to produce hydrogen, the electrode sheet 12 prepared by the iron-cobalt-nickel-based catalyst and the uniformly distributed precursor solution can make the water decomposition reaction proceed at a lower overpotential, thereby improving energy utilization efficiency and reducing the consumption of electric energy. In addition, it also helps to reduce the volume change of the electrode during the charge and discharge cycle. If the precursor solution is unevenly distributed, the internal stress of the electrode sheet 12 will be concentrated in certain areas, resulting in the destruction of the electrode structure, such as cracks. Uniform distribution can make the stress distribution more uniform, and the electrode sheet 12 can better withstand these volume changes, thereby extending the service life of the electrode.

[0041] In some embodiments of the present invention, Figure 2 As shown, the requirements of electrodes of different sizes can be adapted by changing the size of the spiral track belt 3. The requirements of preparing different centrifugal forces can be adapted by changing the pitch of the spiral track belt 3 and coordinating the rotation speed of the rotating motor 9.

[0042] In some embodiments of the present invention, a conveyor belt is provided on the spiral track belt 3 for driving the spiral track belt 3 to generate radial motion. The spiral track belt 3 is divided into a plurality of spiral track grids 5 by a plurality of partitions 6 .

[0043] In some embodiments of the present invention, a feeding device 11 for feeding electrode sheets 12 into the spiral track 2 grids in the spiral track 2 belt is provided at the inlet of the rotating outer cylinder 1. Under the action of the feeding device 11, the electrode sheets 12 can be placed grid by grid in the spiral track grids 3 with holes 14 formed by the partitions 6 in the spiral track belt 2.

[0044] Specifically, the specific structure of the feeding device 11 can be selected from two options: (1) If machine feeding is used, the utility model patent "A card-dealing machine with good adaptability" with application number CN202420620826.7 applied by Microstar Innovation Technology (Shenzhen) Technology Co., Ltd. is cited, and the structure of its card-dealing machine is used in conjunction with the present invention to realize the feeding function of the present invention. (2) The feeding operation of the present invention can also be carried out by manual feeding to realize continuous production. The feeding sheet can be directly added manually or through a funnel.

[0045] In some embodiments of the present invention, a UV ultraviolet reaction box 13 sleeved on the spiral track belt 2 is provided downstream of the rotating outer cylinder 1, and a plurality of UV ultraviolet lamps (not shown in the figure) are installed in the UV ultraviolet reaction box 13. UV ultraviolet light is used to degrade transition metal chlorides, nitrates, and organic metal compounds such as iron, cobalt, and nickel to prepare high-performance self-supporting gas diffusion electrodes, without the need to use adhesives to prepare electrode sheets 12. The ultraviolet lamps in the present invention can be set to different types of ultraviolet lamps, because ultraviolet light of different wavelengths has different degradation effects on transition metal compounds. In general, ultraviolet light with a shorter wavelength (such as 200-250nm) has higher energy and can more effectively break chemical bonds, but it may also cause excessive damage to other components of the electrode. Therefore, it is necessary to select a suitable wavelength according to the type of transition metal compound and the specific requirements of the electrode. For example, for compounds containing iron-carbon bonds, ultraviolet light with a wavelength of about 254nm may be required to selectively break the chemical bond. The light intensity is also critical. Appropriate intensity can ensure sufficient energy input to trigger the degradation reaction, but too high an intensity may cause local overheating or excessive reaction, causing the transition metal particles to agglomerate.

[0046] In some embodiments of the present invention, a plurality of UV lamps are arranged around the UV reaction box 13 to more evenly irradiate the surface of the electrode sheet 12. The use of UV light to fully irradiate the surface of the electrode sheet 12 to degrade the transition metal compound can accurately control the distribution and morphology of the transition metal in the electrode, thereby improving the electrode performance.

[0047] In some embodiments of the present invention, a material collector 4 is provided downstream of the UV ultraviolet reaction box 13 and is sleeved on the spiral track 2 belt for collecting the electrode sheets 12 that have been subjected to light reaction in the UV ultraviolet reaction box 13. The material collector 4 is provided with a plurality of collecting paddles 10 for collecting the electrode sheets 12 in the grids of the spiral track 2. Specifically, a rigid spring is used to fix one end of the collecting paddle 10 on the inner wall of the material collector 4, and the other end is fitted with the groove of the spiral track belt 3. The rigid spring is used to prevent the mechanical jam of the spiral track belt 3 caused by failure to timely remove the material.

[0048] The working steps of the spiral track centrifugal spin coating continuous UV preparation of the self-supporting gas diffusion electrode device of the present invention are:

[0049] S1: cutting, degreasing, cleaning, and impregnating the titanium felt, nickel felt, stainless steel felt, carbon paper, and other porous fiber sheet electrodes (electrode sheets 12) through the feeding device 11 into the spiral track grid 3 with holes 14 divided by the partition 6;

[0050] S2: Power on and start the rotating motor 9, which drives the rotating outer cylinder 1 to rotate at a constant speed through the outer cylinder gear 8, so that the iron-cobalt-nickel precursor slurry impregnated on the surface and inside of the electrode sheet 12 is distributed more evenly under the action of the rotating centrifugal force;

[0051] S3: the electrode sheet 12 after homogenization treatment enters the UV reaction box 13 along the spiral track belt 3 for light irradiation reaction to prepare a self-supporting gas diffusion electrode;

[0052] S4: the self-supporting gas diffusion electrode product prepared in step S3 enters the material collector 4 along the spiral track belt 3, and is collected and taken off the production line with the assistance of the collecting paddle 10.

[0053] 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, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device, characterized in that: The invention comprises a spiral track belt (3) and a rotating outer cylinder (1) sleeved on the spiral pipe belt (3); an inner track (2) matching with the spiral track belt (3) is arranged inside the rotating outer cylinder (1); a driving component for driving the rotating outer cylinder (1) to rotate circumferentially is arranged on the outer wall of the rotating outer cylinder (1); and a plurality of electrode sheets (12) to be processed are arranged at intervals inside the spiral track belt (3).

2. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 1, characterized in that: Continuous spiral track grids (5) for placing electrode sheets (12) are arranged in sequence at intervals in the spiral track belt (3).

3. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 2, characterized in that: A plurality of holes (14) are arranged at the bottom of the spiral track grid (5).

4. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 1, characterized in that: The spiral track belt (3) is provided with a conveyor belt (7) for driving the spiral track belt (3) to generate radial movement.

5. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 2, characterized in that: The spiral track grid (5) is sequentially divided by a plurality of partitions (6).

6. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 1, characterized in that: The electrode sheet (12) entering the rotating outer cylinder (1) is immersed in an iron-cobalt-nickel precursor solution.

7. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 1, characterized in that: A feeding device (11) for feeding electrode sheets (12) into the spiral track grid (5) in the spiral track belt (3) is provided at the inlet of the rotating outer cylinder (1).

8. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 1, characterized in that: A UV reaction box (13) sleeved on the spiral track belt (3) is arranged downstream of the rotating outer cylinder (1), and a plurality of UV lamps are installed in the UV reaction box (13); the plurality of UV lamps are arranged along the periphery of the UV reaction box (13).

9. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 8, characterized in that: A material collector (4) sleeved on the spiral track belt (3) is arranged downstream of the UV ultraviolet reaction box (13) and is used to collect the electrode sheets (12) that have undergone light irradiation reaction in the UV ultraviolet reaction box (13).

10. The spiral track centrifugal spin coating continuous UV self-supporting gas diffusion electrode device according to claim 9, characterized in that: The material collector (4) is provided with a plurality of collecting paddles (10) for collecting the electrode sheets (12) in the spiral track grid (5).

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