Cathode of electrolytic deoxidation device and preparation method thereof, electrolytic deoxidation device and refrigerator

Abstract

The present invention provides a cathode for an electrolytic deoxidation device, a method for preparing the same, an electrolytic deoxidation device, and a refrigerator. The cathode for the electrolytic deoxidation device comprises a catalytic membrane, the catalytic membrane being made from a precursor through a pressing process; and the precursor comprising carbon particles and catalytic particles deposited on at least a portion of the carbon particles, wherein the catalytic particles are selected from the group consisting of platinum, gold, silver, manganese, and rubidium. Since carbon particles are conductive, and precious and rare metals such as platinum, gold, silver, manganese, and rubidium can promote the adsorption and reduction of oxygen, the present invention provides a new cathode for an electrolytic deoxidation device by combining carbon particles and catalytic particles, which has significantly improved electrocatalytic performance, thereby facilitating an increase in the electrochemical reaction rate of the cathode.

Description

Technical Field

[0001] The invention relates to refrigeration equipment, in particular to a cathode of an electrolytic deoxidation device and a preparation method thereof, the electrolytic deoxidation device and a refrigerator. Background Art

[0002] An electrolytic deoxidizer is a device that consumes oxygen by an electrochemical reaction under the action of an electrolytic voltage. The electrolytic deoxidizer comprises a cathode and an anode, with the cathode utilizing oxygen as a reactant to perform an electrochemical reaction, thereby consuming oxygen.

[0003] The inventors have recognized that cathode performance is a key factor affecting the deoxidation efficiency of electrolytic deoxidation devices. Some prior art methods directly use graphite as the cathode, which has low electrocatalytic performance and a slow electrochemical reaction rate, resulting in low deoxidation efficiency. Summary of the Invention

[0004] An object of the present invention is to overcome at least one technical defect in the prior art and to provide a cathode of an electrolytic deoxidation device and a preparation method thereof, an electrolytic deoxidation device and a refrigerator.

[0005] A further object of the present invention is to provide a new cathode for an electrolytic deoxidation device to improve the electrocatalytic performance of the cathode, thereby increasing the electrochemical reaction rate of the cathode.

[0006] A still further object of the present invention is to improve the conductivity of cathodes used in electrolytic deoxidation devices.

[0007] Another further object of the present invention is to increase the effective active area of ​​the cathode used in an electrolytic deoxidation device.

[0008] A further object of the present invention is to provide a cathode for an electrolytic deoxidation device with waterproof and breathable properties.

[0009] In particular, according to one aspect of the present invention, a cathode for an electrolytic deoxidation device is provided, comprising: a catalytic membrane, the catalytic membrane being made of a precursor through a pressing process; and the precursor comprising carbon particles and catalytic particles deposited on at least a portion of the carbon particles, wherein the catalytic particles are selected from the group consisting of platinum, gold, silver, manganese and rubidium.

[0010] Optionally, the carbon particles include hydrophilic carbon particles; and the catalytic particles are deposited on the hydrophilic carbon particles, and the catalytic particles are configured to be dispersed in an aqueous solution containing the hydrophilic carbon particles to be deposited on the hydrophilic carbon particles.

[0011] Optionally, the catalytic membrane is a porous membrane having vents formed thereon for gas to pass through; and the carbon particles further include hydrophobic carbon particles; the hydrophobic carbon particles are configured to be dispersed in the hydrophilic carbon particles so that the catalytic membrane forms vents.

[0012] Optionally, the precursor further includes a binder dispersed in the carbon particles and configured to enable the precursor to form a three-dimensional network structure through a pressing process at a preset temperature.

[0013] Optionally, the cathode further includes: a current collecting net, which is arranged on one side of the catalytic membrane, and the material of the current collecting net is nickel or titanium.

[0014] Optionally, the cathode further includes: a first waterproof and breathable membrane, which is arranged between the current collecting network and the catalytic membrane, and has first capillary pores formed therein for only gas to pass through, and the first capillary pores are configured to form a first meniscus when in contact with the electrolyte.

[0015] Optionally, the cathode also includes: a second waterproof and breathable membrane, which is arranged on the side of the collecting net facing away from the catalytic membrane, and has a second capillary pore formed inside the membrane for only gas to pass through, and the second capillary pore is configured to form a second meniscus when in contact with the electrolyte; the first waterproof and breathable membrane and the second waterproof and breathable membrane are respectively made of polytetrafluoroethylene emulsion by a wet method to form first capillary pores and second capillary pores for only gas to pass through, respectively.

[0016] According to another aspect of the present invention, a method for preparing a cathode for an electrolytic deoxidation device as described above is provided, comprising: depositing catalytic particles on at least a portion of carbon particles to prepare a precursor; and pressing the precursor to obtain a catalytic membrane.

[0017] Optionally, the step of depositing catalytic particles on at least a portion of the carbon particles to prepare a precursor includes: dispersing hydrophilic carbon particles in an aqueous solution containing a surfactant to obtain a first dispersion; dispersing catalytic particles in the first dispersion so that the catalytic particles are deposited on the hydrophilic carbon particles, thereby obtaining a second dispersion; dispersing hydrophobic carbon particles and a binder in the second dispersion to obtain a third dispersion; adding ethanol to the third dispersion for mixing, and drying to obtain a precursor.

[0018] Optionally, the method for preparing the cathode for the electrolytic deoxidation device further includes: preparing a first waterproof breathable membrane and a second waterproof breathable membrane by a wet method using polytetrafluoroethylene emulsion; and pressing the second waterproof breathable membrane, the current collecting net, the first waterproof breathable membrane, and the catalytic membrane in the order of arrangement to obtain the cathode.

[0019] According to another aspect of the present invention, there is provided an electrolytic deoxidation device, comprising: a cathode for an electrolytic deoxidation device as described in any one of the above items.

[0020] According to another aspect of the present invention, a refrigerator is provided, comprising: a cabinet having a storage space formed therein; and the electrolytic deoxidation device as described above, for reducing the oxygen content in the storage space through an electrochemical reaction.

[0021] The cathode of the electrolytic deoxidizer and its preparation method, the electrolytic deoxidizer and the refrigerator of the present invention are as follows: since the catalytic film of the cathode of the electrolytic deoxidizer includes carbon particles and catalytic particles deposited on at least a portion of the carbon particles, and the catalytic particles are selected from a substance group consisting of precious metals and rare metals such as platinum, gold, silver, manganese and rubidium, the carbon particles have conductivity, and the precious metals and rare metals such as platinum, gold, silver, manganese and rubidium can promote the adsorption and reduction of oxygen, therefore, by combining the carbon particles and the catalytic particles, the present invention provides a new cathode for the electrolytic deoxidizer, which has significantly improved electrocatalytic performance, thereby facilitating an increase in the electrochemical reaction rate of the cathode.

[0022] Furthermore, the cathode of the electrolytic deoxidation device of the present invention, its preparation method, the electrolytic deoxidation device and the refrigerator, because the carbon particles have excellent electrical conductivity, use at least part of the carbon particles as a carrier of the catalytic particles, which can reduce the electrochemical impedance of the entire catalytic membrane and improve the conductivity of the cathode used for the electrolytic deoxidation device, thereby ensuring the smooth progress of the electrochemical reaction.

[0023] Furthermore, the cathode of the electrolytic deoxidation device and its preparation method, the electrolytic deoxidation device and the refrigerator of the present invention, since the catalytic membrane is a porous membrane, the vent holes of the catalytic membrane can not only provide a smooth channel for the diffusion of oxygen, but also increase the exposed area of ​​the catalytic particles, thereby increasing the effective active area of ​​the cathode used for the electrolytic deoxidation device, thereby further improving the electrochemical reaction rate of the cathode.

[0024] Furthermore, the cathode of the electrolytic deoxidizer of the present invention, its preparation method, the electrolytic deoxidizer, and the refrigerator are formed by pressing according to the arrangement order of the first waterproof breathable membrane, the current collecting network, the second waterproof breathable membrane, and the catalytic membrane, and the first waterproof breathable membrane and the second waterproof breathable membrane respectively have first capillary pores and second capillary pores for only gas to pass through. This enables the cathode of the electrolytic deoxidizer to have waterproof and breathable properties, thereby ensuring that oxygen can smoothly reach the catalytic membrane from the outside to the inside, and preventing the electrolyte from escaping from the inside to the outside.

[0025] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0027] Figure 1 is a schematic diagram of a cathode for an electrolytic deoxidation device according to one embodiment of the present invention;

[0028] Figure 2 is an exploded view of a cathode for an electrolytic deoxidation device according to one embodiment of the present invention;

[0029] Figure 3 is a flow chart for preparing a cathode for an electrolytic deoxidation device according to one embodiment of the present invention;

[0030] Figure 4 is a schematic diagram of an electrolytic deoxidation device according to one embodiment of the present invention;

[0031] Figure 5 yes Figure 4 An exploded view of the electrolytic deoxidation apparatus is shown;

[0032] Figure 6 yes Figure 5 A partial enlarged view of point A in the middle;

[0033] Figure 7 yes Figure 5 Schematic diagram of the support member in the electrolytic deoxidation device shown;

[0034] Figure 8 yes Figure 7 A partial enlarged view of point B in the middle;

[0035] Figure 9 is a schematic diagram of a refrigerator according to one embodiment of the present invention. DETAILED DESCRIPTION

[0036] Figure 1 1 is a schematic diagram of a cathode 120 of an electrolytic deoxidation device 100 according to an embodiment of the present invention. In the electrolytic deoxidation device 100, under the action of the electrolysis voltage, oxygen in the air can undergo a reduction reaction at the cathode 120, for example, O2+2H2O+4e - →4OH - The cathode 120 may generally include a catalyst membrane 122 for catalyzing the above-mentioned reduction reaction, thereby increasing the electrochemical reaction rate.

[0037] The catalytic film 122 is made of a precursor by pressing. The precursor can be in powder form.

[0038] The precursor includes carbon particles and catalytic particles deposited on at least a portion of the carbon particles, wherein the catalytic particles are selected from the group consisting of platinum, gold, silver, manganese and rubidium, which are noble metals or rare metals.

[0039] The carbon particles have electrical conductivity and can be carbon black, preferably conductive carbon black, such as acetylene black. In some optional embodiments, the carbon particles can also be graphite with good electrical conductivity, which can improve the electrical conductivity of the carbon particles.

[0040] In the cathode 120 of the electrolytic deoxidation device 100 of this embodiment, since the catalytic film 122 includes carbon particles and catalytic particles deposited on at least a portion of the carbon particles, the catalytic particles are selected from a group consisting of precious metals and rare metals such as platinum, gold, silver, manganese, and rubidium. The carbon particles are conductive, and the precious metals and rare metals such as platinum, gold, silver, manganese, and rubidium can promote the adsorption and reduction of oxygen. Therefore, by combining the carbon particles and the catalytic particles, this embodiment provides a new cathode 120 for the electrolytic deoxidation device 100, which has significantly improved electrocatalytic performance, thereby facilitating an increase in the electrochemical reaction rate of the cathode 120.

[0041] Since carbon particles have excellent electrical conductivity, using at least some of the carbon particles as carriers of catalytic particles can reduce the electrochemical impedance of the entire catalytic membrane 122 and improve the conductivity of the cathode 120 of the electrolytic deoxidation device 100, thereby ensuring the smooth progress of the electrochemical reaction.

[0042] In this embodiment, the catalytic particles may be silver. The following uses silver as an example to describe the catalytic process of the catalytic particles. Those skilled in the art should be fully capable of expanding upon this embodiment to other types of catalytic particles, and no further examples will be given here.

[0043] The catalytic effect of silver is beneficial to the four-electron reaction of oxygen reduction (O2+2H2O+4e - =4OH - ), and can hinder the two-electron reaction of the oxygen reduction process (O2+2H2O+2e - =2H2O2, 2H2O2=2H2O+O2↑). A four-electron reaction involves oxygen being directly reduced to H2O by continuously acquiring four electrons. A two-electron reaction involves oxygen first being reduced to H2O2 by acquiring two electrons, and then further reduced to H2O through an electron-accepting reaction. The hydrogen peroxide generated by the two-electron reaction can slowly decompose at room temperature to form oxygen and water. Because the two-electron reaction transfers fewer electrons, it releases less energy, resulting in a lower battery operating voltage.

[0044] Ag catalytic particles can effectively promote HO2 - Decomposition of (HO2 - It is the intermediate product of the two-electron reaction of oxygen in water to generate hydrogen peroxide, O2+H2O+2e - =HO2 - +OH - , which is also the hydrolysis product of H2O2 in water. ). The Ag catalytic particles of this embodiment have defect sites on their surface, and Ag has a strong affinity for OH. -The adsorption force gradually increases with the increase of Ag surface defect sites, thereby hindering the oxygen reduction reaction from proceeding through the two-electron reaction pathway and favoring the four-electron reaction pathway. Furthermore, the inventors recognized that the equilibrium potential of Pt / PtO is approximately 0.2V lower than that of Ag / Ag2O, so the Ag catalytic particles have better stability for the oxygen reduction reaction system.

[0045] The carbon particles may include hydrophilic carbon particles, such as hydrophilic acetylene black.

[0046] The catalytic particles are deposited on the hydrophilic carbon particles, and the catalytic particles are configured to be dispersed in an aqueous solution containing the hydrophilic carbon particles so as to deposit on the hydrophilic carbon particles. That is, to deposit the catalytic particles on the hydrophilic carbon particles, an aqueous solution containing the hydrophilic carbon particles can be first prepared, and then the catalytic particles can be dispersed in the aqueous solution containing the hydrophilic carbon particles. The catalytic particles are sieved through a 400-mesh sieve. The particle size of the catalytic particles can be any value less than or equal to 50 microns, such as 40 microns, 30 microns, or 20 microns. The particle size of the hydrophilic carbon particles can be any value less than or equal to 50 microns, such as 40 microns, 30 microns, or 20 microns.

[0047] The catalytic membrane 122 can be a porous membrane having vents formed therein for gas passage. The porosity of the catalytic membrane 122 can be any value within the range of 60% to 98%, for example, 75% or 90%. The pore diameter of the vents can be any value less than or equal to 100 microns, for example, 1 micron, 20 microns, or 50 microns.

[0048] In some embodiments, the carbon particles may further include hydrophobic carbon particles, such as hydrophobic acetylene black. The hydrophobic carbon particles are dispersed within the hydrophilic carbon particles (i.e., the hydrophobic and hydrophilic carbon particles are mixed to form a uniform mixture) to form vents within the catalytic membrane 122. Since the cathode 120 is immersed in the electrolyte of the electrolytic deoxidation device 100, the hydrophobic properties of the hydrophobic carbon particles can be utilized to form small gas channels, i.e., the aforementioned vents, within the catalytic membrane 122.

[0049] Since the catalytic membrane 122 is a porous membrane, the vent holes of the catalytic membrane 122 can not only provide a smooth channel for the diffusion of oxygen, but also increase the exposed area of ​​the catalytic particles, thereby increasing the effective active area of ​​the cathode 120 used for the electrolytic deoxidation device 100, thereby further improving the electrochemical reaction rate of the cathode 120.

[0050] In some embodiments, the precursor may further include a binder, such as polytetrafluoroethylene, which is dispersed in the carbon particles, that is, the binder can be mixed with the carbon particles to form a uniform mixture, wherein the carbon particles include hydrophilic carbon particles and hydrophobic carbon particles, and the hydrophilic carbon particles are loaded with catalytic particles. The binder is configured to cause the precursor to form a three-dimensional network structure by pressing at a preset temperature. That is, the catalytic film of this embodiment can be made of a precursor by hot pressing. The binder has a certain viscosity, and its bonding effect can form a three-dimensional network of active substances such as catalytic particles and carbon particles, which can make the active substances not easy to fall off, which is beneficial to improving the structural strength and structural stability of the catalytic film 122.

[0051] The binder lacks hydrophilic groups and has low hygroscopicity, which can result in a high ohmic impedance for the catalyst film 122, hindering sufficient contact between the catalytic particles and the electrolyte. In this embodiment, the conductivity of the catalyst film 122 can be improved by introducing hydrophobic acetylene black into the precursor. Furthermore, because acetylene black is hydrophobic, it can form tiny gas pores within the catalyst film 122, reducing gas diffusion resistance and facilitating the formation of a three-phase reaction interface.

[0052] Figure 2 FIG. 1 is an exploded view of a cathode 120 of an electrolytic deoxidation device 100 according to an embodiment of the present invention.

[0053] In some embodiments, the cathode 120 can be a multi-layer membrane structure, and can further include a current collecting net 126. The current collecting net 126 can be arranged on one side of the catalytic membrane 122, and the material of the current collecting net 126 can be nickel or titanium. In this embodiment, the current collecting net 126 can be a nickel mesh or a titanium mesh, which has high mechanical strength so that it can serve as the supporting structure and conductive skeleton of the entire cathode 120, and is formed with pores for gas to pass through so that oxygen can pass through and diffuse to the catalytic membrane 122. The catalytic membrane 122 and the waterproof and breathable membrane described below can be attached to the current collecting net 126 by hot pressing. When a nickel mesh is selected as the current collecting net 126, the nickel purity can be greater than or equal to 99.6%.

[0054] In some further embodiments, the cathode 120 may further include two waterproof and breathable membranes, namely a first waterproof and breathable membrane 124 and a second waterproof and breathable membrane 128. The waterproof and breathable membrane of this embodiment can play the role of "waterproof" and "breathable", on the one hand, preventing water or aqueous solutions from passing through, and on the other hand, allowing gases such as oxygen to pass through.

[0055] The first waterproof, breathable membrane 124 can be disposed between the current collecting net 126 and the catalytic membrane 122, and has first capillary pores formed therein, allowing only gas to pass through. The first capillary pores are configured to form a first meniscus when in contact with the electrolyte. The second waterproof, breathable membrane 128 can be disposed on the side of the current collecting net 126 facing away from the catalytic membrane 122, and has second capillary pores formed therein, allowing only gas to pass through. The second capillary pores are configured to form a second meniscus when in contact with the electrolyte.

[0056] That is, the cathode 120 of this embodiment has a four-layer membrane structure, arranged in the following order: a second waterproof and breathable membrane 128, a current collecting net 126, a first waterproof and breathable membrane 124, and a catalytic membrane 122. The second waterproof and breathable membrane 128 can be located at the outermost layer of the cathode 120, for example, facing the storage space of the refrigerator 10. The catalytic membrane 122 can be located at the innermost layer of the cathode 120, for example, facing the liquid storage chamber of the electrolytic deoxidation device 100. Oxygen in the storage space flows through the second waterproof and breathable membrane 128, the current collecting net 126, and the first waterproof and breathable membrane 124 in sequence before reaching the catalytic membrane 122. The four membrane layers can each be rectangular thin films, with the length and width of each layer being approximately the same and adjustable based on the size of the workspace. For example, the length of each layer can be 100 to 300 mm, and the width of each layer can be 50 to 200 mm. In some embodiments, the current collecting net can be larger than the other membrane layers.

[0057] Since the cathode 120 is formed by pressing in the order of the first waterproof breathable membrane 124, the current collecting net 126, the second waterproof breathable membrane 128, and the catalytic membrane 122, and the first waterproof breathable membrane 124 and the second waterproof breathable membrane 128 respectively have first capillary pores and second capillary pores for only gas to pass through, the cathode 120 of the electrolytic deoxidation device 100 has waterproof and breathable properties, which can ensure that oxygen can smoothly reach the catalytic membrane 122 from the outside to the inside, and prevent the electrolyte from escaping from the inside to the outside.

[0058] The waterproof, breathable membrane provides a gas-permeable interface between air and the electrolyte, creating a path for oxygen to enter and diffuse into the catalytic membrane 122. The waterproof, breathable membrane's ability to allow air to pass without leaking liquids is primarily due to the capillary action of the inner walls of the pores and the hydrophobic nature of the adhesive material. The contact between the pores and the electrolyte forms menisci, namely the aforementioned first and second menisci.

[0059] The first and second waterproof breathable membranes 124, 128 can have identical structures and components. In this embodiment, the first and second waterproof breathable membranes 124, 128 can each be made from a polytetrafluoroethylene (PTFE) emulsion using a wet process to form first and second capillary pores, respectively, that are gas-only. The mass concentration of the PTFE emulsion can be anywhere between 40% and 80%, for example, 60%. Using a specific concentration of PTFE emulsion in a wet process to form the waterproof breathable membrane ensures that the pore diameter and porosity of the membrane are within reasonable ranges, thereby meeting the required waterproof and breathable performance. In this embodiment, the pore diameter can be any value less than or equal to 100 microns, for example, 1 micron, 20 microns, or 50 microns. The porosity of the membrane can be anywhere between 60% and 98%, for example, 70% or 90%.

[0060] The inventors have recognized that polytetrafluoroethylene (PTFE) has poor electrical conductivity, which results in a high ohmic impedance for the entire cathode 120. To increase the conductivity of the waterproof breathable membrane, reduce the amount of PTFE used, lower the manufacturing cost of the cathode 120, enhance the adhesion and plasticity between the various components of the waterproof breathable membrane, and improve the waterproof and breathable properties of the waterproof breathable membrane, in some further embodiments, appropriate amounts of acetylene black and activated carbon may be added to the waterproof breathable membrane.

[0061] Figure 3 1 is a flow chart for preparing a cathode 120 for an electrolytic deoxidation device 100 according to one embodiment of the present invention. This flow chart is suitable for preparing a cathode 120 for an electrolytic deoxidation device 100 according to any of the above embodiments. The method for preparing a cathode 120 for an electrolytic deoxidation device 100 may generally include:

[0062] Step S302: Depositing catalytic particles on at least a portion of the carbon particles to prepare a precursor. The catalytic particles are selected from the group consisting of platinum, gold, silver, manganese, and rubidium. The carbon particles are conductive.

[0063] In step S304, the precursor is pressed to obtain the catalytic film 122. The pressing process can be performed at a preset temperature. During the hot pressing process, the hot pressing temperature can be any value in the range of 200-500°C, for example, 300°C; the hot pressing pressure can be any value in the range of 1000-5000 kN, for example, 1500 kN or 3000 kN; and the hot pressing time can be any value in the range of 1 minute to 5 hours, for example, 1 minute, 1 hour, or 3 hours.

[0064] The above-mentioned step S304 may include: dispersing hydrophilic carbon particles in an aqueous solution containing a surfactant to obtain a first dispersion; dispersing catalytic particles in the first dispersion so that the catalytic particles are deposited on the hydrophilic carbon particles, thereby obtaining a second dispersion; dispersing hydrophobic carbon particles and a binder in the second dispersion to obtain a third dispersion; adding ethanol to the third dispersion for mixing, and drying to obtain a precursor.

[0065] In other words, during the precursor preparation process, an aqueous solution containing a surfactant is first prepared, and hydrophilic carbon particles are dispersed in the surfactant-containing water to obtain a first dispersion. Catalytic particles are then deposited onto the hydrophilic carbon particles to obtain a second dispersion. Hydrophobic carbon particles and a binder are then added to the second dispersion and thoroughly mixed to obtain a third dispersion. Finally, ethanol is added to the third dispersion and thoroughly mixed to self-organize the dispersion. The dispersion is then dried to obtain the precursor powder. The thickness of the catalytic film 122 can be 0.2 to 0.3 mm, and the surface resistance can be 1.2 to 1.5 kΩ.

[0066] In this embodiment, after the above step S304, the method for preparing the cathode 120 of the electrolytic deoxidation device 100 may further include:

[0067] Step S306: using polytetrafluoroethylene emulsion to form the first waterproof breathable membrane 124 and the second waterproof breathable membrane 128 by a wet process.

[0068] In step S308 , the second waterproof and breathable membrane 128 , the current collecting net 126 , the first waterproof and breathable membrane 124 , and the catalytic membrane 122 are pressed in the order of arrangement to obtain the cathode 120 .

[0069] In the step of preparing the first waterproof breathable membrane 124 and the second waterproof breathable membrane 128 by a wet process using polytetrafluoroethylene emulsion, appropriate amounts of acetylene black and activated carbon may be added to improve the performance of the waterproof breathable membranes.

[0070] For example, a method for preparing a waterproof breathable membrane may include the following steps: weighing 9g of activated carbon, 30mL of polytetrafluoroethylene emulsion, and 7.5g of acetylene black, adding an appropriate amount of ethanol, subjecting the mixture to ultrasonic dispersion for 5 minutes, heating and stirring the mixture in a water bath at 45°C to 95°C until agglomerates form. The agglomerates are then repeatedly rolled on a double-roll press at 50°C to 60°C to fiberize the polytetrafluoroethylene, resulting in a waterproof breathable membrane with a thickness of approximately 0.6-0.8mm. The surface resistance of the waterproof breathable membrane may be 130-180Ω.

[0071] In some embodiments, the order of steps S302, S304, and S306 can be adjusted according to actual conditions. For example, the catalytic membrane 122 and the waterproof breathable membrane can be prepared simultaneously, or the waterproof breathable membrane can be prepared first and then the catalytic membrane 122.

[0072] Figure 4 is a schematic diagram of an electrolytic deoxidation device 100 according to one embodiment of the present invention. Figure 5 yes Figure 4 An exploded view of the electrolytic deoxidation device 100 is shown.

[0073] The electrolytic deoxidation device 100 may generally include a cathode 120 as in any of the above embodiments, and may further include an anode 140 corresponding to the cathode 120 and a housing 110 for providing a liquid storage chamber for containing electrolyte.

[0074] In this embodiment, the housing 110 can be roughly rectangular in shape and can have a side opening 114 and a top opening. The cathode 120 can be disposed at the side opening 114 and seal the side opening 114, thereby defining a liquid storage chamber for containing an electrolyte together with the housing 110. The liquid storage chamber of the electrolytic deoxidation device 100 can contain an alkaline electrolyte, such as 5 mol / L NaOH, the concentration of which can be adjusted according to actual needs.

[0075] The anode 140 and the cathode 120 are spaced apart from each other and are arranged in the liquid storage chamber. For example, the anode 140 can be nickel foam or nickel mesh, which has good corrosion resistance and high catalytic activity. The anode 140 is used to provide reactants (such as electrons) to the cathode through electrochemical reaction and generate oxygen. The OH generated by the cathode 120 - An oxidation reaction may occur at the anode 140 and generate oxygen, namely: 4OH - →O2+2H2O+4e - The anode 140 has an anode power supply terminal 142 extending from the housing 110 and connected to the positive pole of an external power source. The cathode 120 has a cathode power supply terminal 152b extending from the housing 110 and connected to the negative pole of an external power source.

[0076] The top opening of the shell 110 can be used as an exhaust port and is used to discharge the oxygen generated by the anode 140. Since the liquid storage chamber contains electrolyte, arranging the exhaust port at the top of the shell 110 can reduce or avoid leakage of the electrolyte. In some optional embodiments, the exhaust port can also serve as a refill port for the electrolyte. When the electrolyte is insufficient, the electrolyte can be injected into the liquid storage chamber at the exhaust port, which can realize the functional reuse of the exhaust port and is conducive to simplifying the structure of the electrolytic deoxidation device 100. In other optional embodiments, the electrolytic deoxidation device may also include an exhaust pipe 160, which is connected to the exhaust port and is used to guide the airflow out of the exhaust port to the external environment of the shell 110.

[0077] In some embodiments, the electrolytic deoxidation device 100 may further include a separator 130 and a fixing assembly 150 .

[0078] The separator 130 is disposed within the liquid storage chamber and is located between the cathode 120 and the anode 140. A plurality of raised portions 132 are formed on the side of the separator facing the anode 140. The raised portions 132 abut against the anode 140 to separate the cathode 120 from the anode 140 and prevent a short circuit in the electrolytic deoxidation device 100. Specifically, the separator 130 has a plurality of raised portions 132 formed on the side facing the anode 140. The raised portions 132 abut against the anode 140. The cathode 120 abuts against the side of the separator 130 facing away from the raised portions 132, thereby forming a predetermined gap between the cathode 120 and the anode 140, thereby separating the cathode 120 from the anode 140.

[0079] The fixing assembly 150 may be disposed outside the cathode 120 and configured to fix the cathode 120 to the lateral opening 114 of the housing 110 . Specifically, the fixing assembly 150 may further include a metal frame 152 and a support member 154 .

[0080] Figure 6 yes Figure 5 A partial enlarged view of point A in the middle. Figure 7 yes Figure 5 The schematic diagram of the support member 154 in the electrolytic deoxidation device 100 is shown. Figure 8 yes Figure 7A partial enlarged view of point B in the middle. The metal frame 152 is abutted against the outer side of the cathode 120, and the metal frame 152 protrudes outward to form a surrounding portion 152a. The support member 154 is arranged on the outer side of the metal frame 152, and it has an outer ring 1542 and an inner ring 1544 located inside the outer ring 1542. The outer ring 1542 is fixedly connected to the shell 110, and a plug-in slot 1544a is formed on the inner side of the inner ring 1544. The surrounding portion 152a extends into the plug-in slot 1544a to fix the metal frame 152 and the cathode 120 at the opening. In this embodiment, the metal frame 152 is in direct contact with the cathode 120, and the metal frame 152 can play a role in pressing the cathode 120, and the cathode power supply terminal 152b of the cathode 120 can also be provided on the metal frame 152 to be connected to an external power supply.

[0081] The surrounding portion 152a is formed on the metal frame 152 and extends outward to be inserted into the insertion groove 1544a of the inner ring 1544 of the support member 154, thereby positioning the metal frame 152. Since the outer ring 1542 of the support member 154 is fixedly connected to the housing 110, when the surrounding portion 152a of the metal frame 152 enters the insertion groove 1544a of the support member 154, the metal frame 152 can be fixed and positioned by the support member 154, thereby allowing the metal frame 152 to press against the cathode 120.

[0082] In some embodiments, reinforcing ribs 1546 are formed between the outer ring 1542 and the inner ring 1544 of the support member 154 and inside the inner ring 1544 to fix the outer ring 1542 and the inner ring 1544 of the support member 154 and to shape the outer ring 1542 and the inner ring 1544 of the support member 154 to prevent them from being deformed by external forces.

[0083] Figure 9 FIG. 1 is a schematic diagram of a refrigerator 10 according to an embodiment of the present invention. The refrigerator 10 generally includes a cabinet 200 and an electrolytic deoxidizer 100 according to any of the above embodiments.

[0084] The interior of the box 200 forms a storage space. The electrolytic deoxidation device 100 can be disposed in the storage space or in airflow communication with the storage space to reduce the oxygen content in the storage space through an electrochemical reaction.

[0085] For example, the interior of the box 200 may define at least one storage compartment, and a storage container 300 may be provided in the storage compartment. For example, the storage container 300 may be a storage drawer that can be pulled out and back. The above storage space may refer to the interior space of the storage container 300. The electrolytic deoxidation device 100 may be provided in the storage container 300. When the storage space volume is 15L, at a current density of 60mA / cm 2 In the case of2 Electrolytic deoxidation device 100 (the working areas of cathode and anode are 20cm 2 ), the oxygen concentration can be reduced from 21% to 14% within 30 minutes. Utilizing the cathode 120 provided by the present invention can effectively improve the deoxygenation efficiency of the electrolytic deoxygenation device 100, thereby providing favorable conditions for the preparation of a high-efficiency, energy-saving, low-oxygen fresh-keeping refrigerator, and having application value.

[0086] The cathode 120 of the electrolytic deoxidizer 100 of the present invention, its preparation method, the electrolytic deoxidizer 100, and the refrigerator 10 are as follows: since the catalytic film 122 of the cathode 120 of the electrolytic deoxidizer 100 includes carbon particles and catalytic particles deposited on at least a portion of the carbon particles, and the catalytic particles are selected from the group consisting of precious metals and rare metals such as platinum, gold, silver, manganese, and rubidium, the carbon particles have conductivity, and the precious metals and rare metals such as platinum, gold, silver, manganese, and rubidium can promote the adsorption and reduction of oxygen, therefore, by combining the carbon particles and the catalytic particles, the present invention provides a new cathode 120 for the electrolytic deoxidizer 100, which has significantly improved electrocatalytic performance, thereby facilitating an increase in the electrochemical reaction rate of the cathode 120.

[0087] At this point, those skilled in the art will recognize that, although a number of exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications consistent with the principles of the present invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and deemed to cover all such other variations or modifications.

Claims

1. A cathode for an electrolytic deoxidation device, characterized in that: include: A catalytic film, wherein the catalytic film is made from a precursor by pressing; the precursor includes carbon particles and catalytic particles deposited on at least a portion of the carbon particles, wherein the catalytic particles are selected from the group consisting of platinum, gold, silver, manganese, and rubidium; A current collecting net is provided on one side of the catalytic membrane, and the material of the current collecting net is nickel or titanium; a first waterproof and breathable membrane, disposed between the current collecting net and the catalytic membrane, and having first capillary pores formed therein for only gas to pass through, wherein the first capillary pores are configured to form a first meniscus when in contact with the electrolyte; a second waterproof breathable membrane, disposed on a side of the current collecting net facing away from the catalytic membrane, and having second capillary pores formed therein for passage of only gas, the second capillary pores being configured to form a second meniscus when in contact with the electrolyte; the first waterproof breathable membrane and the second waterproof breathable membrane being respectively made of polytetrafluoroethylene emulsion by a wet process to form the first capillary pores and the second capillary pores, respectively, for passage of only gas; wherein the carbon particles include hydrophilic carbon particles; and the catalytic particles are deposited on the hydrophilic carbon particles, and the catalytic particles are configured to be dispersed in an aqueous solution containing the hydrophilic carbon particles so as to be deposited on the hydrophilic carbon particles; Wherein, the catalytic membrane is a porous membrane, which is formed with air pores for gas to pass through; and the carbon particles also include hydrophobic carbon particles; the hydrophobic carbon particles are configured to be dispersed in the hydrophilic carbon particles so that the catalytic membrane forms the air pores; the pore diameter of the air pores is less than or equal to 100 microns.

2. The cathode for electrolytic deoxidation device according to claim 1, characterized in that: The precursor further includes a binder dispersed in the carbon particles and configured to enable the precursor to form a three-dimensional network structure through the pressing process at a preset temperature.

3. A method for preparing a cathode for an electrolytic deoxidation device according to claim 1 or 2, characterized in that: include: Catalytic particles are deposited on at least a portion of carbon particles to prepare a precursor, the preparation steps comprising: dispersing hydrophilic carbon particles in an aqueous solution containing a surfactant to obtain a first dispersion; dispersing the catalytic particles in the first dispersion so that the catalytic particles are deposited on the hydrophilic carbon particles to obtain a second dispersion; dispersing hydrophobic carbon particles and a binder in the second dispersion to obtain a third dispersion; adding ethanol to the third dispersion, mixing, and drying to obtain the precursor; The precursor is pressed to obtain the catalytic membrane.

4. The method for preparing a cathode for an electrolytic deoxidation device according to claim 3, wherein: Also includes: A first waterproof breathable membrane and a second waterproof breathable membrane are prepared by a wet process using polytetrafluoroethylene emulsion; The cathode is obtained by pressing the second waterproof and breathable membrane, the current collecting net, the first waterproof and breathable membrane, and the catalytic membrane in the order of arrangement.

5. An electrolytic deoxidation device, characterized in that: include: The cathode for an electrolytic deoxidation device according to claim 1 or 2.

6. A refrigerator, characterized in that: include: A box body, wherein a storage space is formed inside the box body; as well as The electrolytic deoxidation device according to claim 5 is used to reduce the oxygen content in the storage space through an electrochemical reaction.

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