Device for'direct capture-conversion power generation 'of nitric oxide with ppm concentration and application of device

Abstract

The invention belongs to the technical field of nitrogen oxide capture, and particularly relates to a device for direct capture-conversion power generation of ppm-concentration nitrogen oxides and application of the device. The device comprises a zinc sheet electrode, an electrolyte and a gas diffusion electrode; the gas diffusion electrode is obtained by coating hydrophobic carbon cloth with electrode slurry; the electrode slurry is formed by mixing an electrode material, conductive carbon and polyvinylidene fluoride in an organic solvent; the electrode material has a structure as shown in a formula (I), in the formula, the value of n is 20 to 100. Compared with the prior art, the problem that a noble metal catalyst adopted by a nitrogen oxide electrochemical reduction technology in the prior art is limited in treatment capacity on low-concentration nitrogen oxide is solved. According to the scheme, a nitrogen oxide direct capture-conversion power generation device is constructed, and effective capture and conversion of NO2 with different concentrations and even ppm-level concentrations can be achieved.

Description

Technical Field

[0001] This invention belongs to the field of nitrogen oxide capture technology, specifically relating to a device for "direct capture-conversion power generation" of ppm concentration nitrogen oxides and its application. Background Technology

[0002] Nitrogen dioxide (NO2), a major air pollutant, primarily originates from factory emissions and vehicle exhaust, posing a serious threat to the environment and human health. Furthermore, nitrogen oxides, represented by nitrogen dioxide, are not only precursors to photochemical smog and acid rain, contributing to surface water acidification and eutrophication, but also directly irritate the respiratory tract, triggering diseases such as asthma. Prolonged exposure to nitrogen dioxide atmospheres can also lead to conditions such as neurasthenia syndrome and chronic respiratory inflammation.

[0003] Currently, industry primarily treats NO2 using technologies such as selective catalytic reduction and alkaline absorption to convert it into harmless substances. However, these methods are costly and cannot achieve resource utilization. Although some research has utilized electrochemical reduction technology to convert NO2 into high-value-added chemical raw materials under the action of noble metal catalysts, existing noble metal catalysts (such as platinum and ruthenium) have significant limitations: on the one hand, they are prone to deactivation due to side reactions or poisoning, resulting in insufficient stability and lifespan; on the other hand, the high cost of the noble metals themselves and the additional electricity demand during operation significantly increase overall energy consumption and economic burden. In addition, the catalytic performance of such noble metal catalysts for low-concentration NO2 is also relatively limited, making it difficult to reliably treat NO2 atmospheres with low concentrations (especially at the ppm level).

[0004] In the prior art, CN112962108A discloses the application of a regenerated electrode from an alkaline zinc-ion battery after charge-discharge cycles in the electrochemical reduction of carbon dioxide. Pure zinc sheets are used as the negative electrode of a nickel-zinc battery, and the chemical composition and structure of the electrode material are adjusted by utilizing the charge and discharge states of the alkaline zinc-ion battery. Two types of regenerated zinc electrodes can be used as cathode catalysts for electrochemical carbon dioxide reduction, each possessing high electrocatalytic activity and selectivity; the core-shell structured zinc@zinc oxide nanowires exhibit excellent carbon monoxide selectivity, while the layered two-dimensional zinc hydroxide nanosheets show preferential formic acid selectivity. However, this scheme achieves carbon dioxide capture and reduction by constructing core-shell structured zinc@zinc oxide nanowires, but does not provide or explain its ability to capture nitrogen oxides. Furthermore, this scheme proposes that the negative electrode product of the alkaline zinc-ion battery can serve as an inexpensive source of carbon dioxide reduction catalysts, but it is not itself a device for the independent reduction of carbon dioxide.

[0005] Therefore, there is a need to develop materials and devices that can capture nitrogen oxides, especially those with good capture capabilities for low concentrations of nitrogen oxides. Summary of the Invention

[0006] The purpose of this invention is to provide a device and its application for "direct capture-conversion power generation" of ppm concentration nitrogen oxides, thereby addressing at least one of the aforementioned problems. This solves the problem that the noble metal catalysts used in existing nitrogen oxide electrochemical reduction technologies have limited processing capacity for low concentrations of nitrogen oxides. This invention constructs a device for "direct capture-conversion power generation" of ppm concentration nitrogen oxides, which can effectively capture and convert NO2 at different concentrations, even at the ppm level.

[0007] The objective of this invention is achieved through the following technical solution: The first aspect of the present invention discloses an apparatus for "direct capture-conversion power generation" of nitrogen oxides at a concentration of ppm, comprising: a zinc sheet electrode, an electrolyte, and a gas diffusion electrode; The gas diffusion electrode is obtained by coating an electrode paste onto a hydrophobic carbon cloth; The electrode paste is formed by mixing electrode material, conductive carbon, and polyvinylidene fluoride in an organic solvent; The electrode material has a structure as shown in formula (I) (naphthylaminoquinone polymer): Formula (I); In the formula, n takes values ​​from 20 to 100.

[0008] Preferably, the electrolyte is one of zinc chloride aqueous solution or zinc trifluoromethanesulfonate; The concentration of the electrolyte is 0.5~3 M.

[0009] Preferably, the electrode slurry is coated onto hydrophobic carbon cloth and then vacuum dried to obtain the gas diffusion electrode. The vacuum drying temperature is 80℃ and the time is 12 hours.

[0010] Preferably, the electrode slurry is formed by mixing electrode material, conductive carbon and polyvinylidene fluoride in an organic solvent at a mass ratio of X:(9~X):1, wherein the value of X is 5~7. The ratio of the mixture of electrode material, conductive carbon and polyvinylidene fluoride to organic solvent is 100 mg: 400 μL; The conductive carbon is Super P or Ketjen Black; The organic solvent is dimethyl sulfoxide or N-methylpyrrolidone.

[0011] Preferably, the thickness of the electrode slurry in the gas diffusion electrode is 200-600 micrometers.

[0012] Preferably, the electrode material is prepared by the following method: 2,3-Dichloro-1,4-naphthoquinone and aromatic amine were added to a solvent and heated to react. The electrode material was then obtained by centrifugation, washing and drying.

[0013] Preferably, the aromatic amine is 1,5-diaminonaphthalene; 2,3-Dichloro-1,4-naphthoquinone reacts with 1,5-diaminonaphthalene in an equimolar ratio; The solvent is water or N,N'-dimethylformamide; The heating reaction was carried out at a temperature of 80°C for 12 hours.

[0014] Preferably, the nitrogen oxide "direct capture-conversion power generation" device further includes a housing; The outer casing includes a negative electrode contact layer, an electrolyte layer, a gas diffusion electrode contact layer, and a sealing gasket, wherein the electrolyte layer and the sealing gasket have through holes. The device for "direct capture-conversion power generation" of nitrogen oxides is constructed by stacking and fixing a negative electrode contact layer, a zinc sheet electrode, a sealing gasket, an electrolyte layer, a sealing gasket, a gas diffusion electrode, and a gas diffusion electrode contact layer. The electrolyte is injected into the casing of the device for "direct capture-conversion power generation" of nitrogen oxides.

[0015] Preferably, the outer casing is secured with screws.

[0016] Preferably, the housing is a PMMA (polymethyl methacrylate) housing.

[0017] The second aspect of the present invention discloses the application of the apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides as described above in the capture and conversion power generation of nitrogen oxides.

[0018] Preferably, the apparatus for "direct capture-conversion power generation" of nitrogen oxides is exposed to a nitrogen dioxide atmosphere to capture, convert, and generate electricity from nitrogen dioxide.

[0019] The working principle of this invention is as follows: After the device discharges, the naphthylaminoquinone polymer in the gas diffusion electrode is reduced and forms a complex with zinc ions. This zinc complex is exposed to nitrogen dioxide and is oxidized back to the initial naphthylaminoquinone polymer structure, while the nitrogen dioxide is reduced to nitrite. During this process, the device voltage increases, and after discharge, a new zinc complex is formed, thereby continuously reducing nitrogen dioxide and releasing electrical energy.

[0020] Compared with the prior art, the present invention has the following beneficial effects: (1) The nitrogen oxide “direct capture-conversion power generation” device constructed by the present invention can be used to capture nitrogen dioxide and convert it into electrical energy in different concentration ranges of nitrogen dioxide. It can be carried out in a nitrogen dioxide atmosphere with a minimum concentration of 1 ppm and has extremely high sensitivity.

[0021] (2) The nitrogen oxide “direct capture-conversion power generation” device constructed by the present invention has the advantages of miniaturization, simple assembly and low cost, and has wide applicability.

[0022] (3) The nitrogen oxide “direct capture-conversion power generation” device of the present invention not only captures nitrogen dioxide in the environment to reduce nitrogen dioxide pollution in the environment, but also further converts nitrogen dioxide into economically valuable electrical energy, which has high economic benefits.

[0023] (4) The nitrogen oxide “direct capture-conversion power generation” device of the present invention has good stability. After working continuously for 168 hours, the released electricity, device voltage, and chemical structure of naphthylaminoquinone polymer all remain relatively stable, and the working life is long. Attached Figure Description

[0024] Figure 1 This is a schematic diagram illustrating the working principle of the nitrogen oxide "direct capture-conversion power generation" device constructed in Example 1.

[0025] Figure 2 This is a scanning electron microscope image of the electrode material prepared in Example 1.

[0026] Figure 3 Infrared images of the electrode material and its raw materials (2,3-dichloro-1,4-naphthoquinone, 1,5-diaminonaphthalene) prepared in Example 1.

[0027] Figure 4 The image shows the nitrogen 1s X-ray photoelectron spectrum of the electrode material and its raw material (1,5-diaminonaphthalene) prepared in Example 1.

[0028] Figure 5 The images show structural photographs of the nitrogen oxide "direct capture-conversion power generation" device constructed in Example 1, including: photographs of components, side-view photographs, and side-view photographs of the gas diffusion electrode.

[0029] Figure 6 The voltage variation diagram of the nitrogen oxide "direct capture-conversion power generation" device built in Example 1 under different NO2 atmosphere concentrations is shown.

[0030] Figure 7 The nitrogen oxide "direct capture-conversion power generation" device built in Example 1 was exposed to 200 ppm NO2 for different times, and then at 2 mA / cm 2and 5 mA / cm 2 Discharge curves at current density.

[0031] Figure 8 The nitrogen oxide "direct capture-conversion power generation" device built in Example 1 was exposed to different concentrations of NO2 atmosphere at 2mA / cm 2 Discharge capacity at current density.

[0032] Figure 9 The nitrogen oxide "direct capture-conversion power generation" device built in Example 6 was continuously exposed to a NO2 atmosphere for 1 hour at a rate of 2 mA / cm². 2 Cyclic stability of discharge performance at a given current density.

[0033] Figure 10 The nitrogen oxide "direct capture-conversion power generation" device built in Example 6 was continuously exposed to a NO2 atmosphere at a rate of 2 mA / cm². 2 Comparison of infrared spectra before and after cycling at a given current density.

[0034] Figure 11 This is a comparison chart showing the decrease in nitrogen dioxide concentration after two hours of discharge in the nitrogen oxide "direct capture-conversion power generation" device built in Example 6 under an initial NO2 environment of 200 ppm.

[0035] Figure 12 The voltage variation diagram and the capacity at different current densities are shown for the nitrogen oxide "direct capture-conversion power generation" device based on pure carbon gas diffusion electrode in Comparative Example 1 under a 200 ppm NO2 environment.

[0036] Figure 13 To compare the nitrogen oxide "direct capture-conversion power generation" device based on the tetraaminop-benzoquinone gas diffusion electrode in Comparative Example 2, the device was exposed to 200 ppm NO2 for 1 hour, followed by exposure to 2 mA / cm². 2 Graph showing the change in cyclic discharge capacity under current density. Detailed Implementation

[0037] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0038] Unless otherwise specified, the reagents used in the following description are conventional commercial products, the methods used are known in the art, and all other matters not covered herein are prior art.

[0039] This invention discloses a device for capturing and converting NO2 of different concentrations into electrical energy (a device for "direct capture-conversion power generation" of nitrogen oxides). It includes a zinc sheet electrode, an electrolyte, and a hydrophobic carbon cloth coated with electrode slurry as a gas diffusion electrode.

[0040] The electrolyte is a 0.5-3 M aqueous solution of zinc chloride or zinc trifluoromethanesulfonate.

[0041] The gas diffusion electrode is prepared by coating electrode slurry onto hydrophobic carbon cloth using a coating machine and then drying it in a vacuum oven at 80 degrees Celsius for 12 hours.

[0042] The electrode paste is a mixture of electrode material, conductive carbon, and polyvinylidene fluoride in an organic solvent at a mass ratio of X:(9~X):1, where X=5~7; and the thickness of the coating on the carbon cloth is 200~600 micrometers. The coating of the electrode paste and the different thicknesses of the electrode paste are achieved by a coating machine.

[0043] The electrode material is a naphthylaminoquinone polymer with the structure shown in formula (I): Formula (I); In the formula, n takes values ​​from 20 to 100.

[0044] The working mechanism of this electrode material in sustainably capturing nitrogen dioxide and converting it into electricity is as follows: Figure 1 The diagram shows that after the device discharges, the naphthylaminoquinone polymer in the gas diffusion electrode is reduced and forms a complex with zinc ions. This zinc complex, when exposed to nitrogen dioxide, is oxidized back to its initial naphthylaminoquinone polymer structure, while the nitrogen dioxide is reduced to nitrite. During this process, the device voltage increases, and new zinc complexes are formed after the discharge, continuously reducing nitrogen dioxide and releasing electrical energy.

[0045] The conductive carbon is either Super P or Ketjen Black conductive carbon.

[0046] The organic solvent is either dimethyl sulfoxide (DMSO) or N-methylpyrrolidone (NMP). It is added according to the ratio of 100 mg:400 μL of mixture (electrode material + conductive carbon + polyvinylidene fluoride) to organic solvent.

[0047] In the above process, the electrode material is made from 2,3-dichloro-1,4-naphthoquinone and aromatic amine (1,5-diaminonaphthalene). The mixture is heated in a solvent, and after the reaction is completed, it is centrifuged, washed, and dried to obtain the polymer.

[0048] 2,3-Dichloro-1,4-naphthoquinone and the aromatic amine 1,5-diaminonaphthalene are mixed in an equimolar ratio, as shown in the following reaction formula: .

[0049] The solvent is water or N,N'-dimethylformamide; the heating temperature is 80 degrees Celsius, and the time is 12 hours. More specifically: in the reaction with water as the solvent, after centrifugation, the product is washed several times with water and ethanol, and finally dried in a vacuum oven at 80 degrees Celsius for 12 hours to obtain the product; in the reaction with N,N'-dimethylformamide (DMF) as the solvent, after the reaction is completed, the hot reaction solution is added to an ice-water mixture, then centrifuged, followed by washing several times with water and ethanol, and finally dried in a vacuum oven at 80 degrees Celsius for 12 hours to obtain the product.

[0050] The electrode slurry is prepared by the following steps: using a balance, the electrode material, conductive carbon and polyvinylidene fluoride are weighed separately according to the mass ratio of X:(9~X):1, where X=5~7. They are then ground and mixed thoroughly using an agate mortar. After that, the mixture is transferred to a stirrable container and dimethyl sulfoxide or N-methylpyrrolidone is added and stirred at room temperature for 12 hours.

[0051] The device also includes an outer shell made of PMMA (polymethyl methacrylate). The outer shell consists of three layers: 1) a negative electrode contact layer; 2) an electrolyte layer; and 3) a gas diffusion electrode contact layer. Each layer is sealed with a gasket to ensure airtightness. A circular groove (serving as a gas chamber for nitrogen dioxide gas to contact the gas diffusion electrode) with a depth of 8-10 mm is provided in the middle of the gas diffusion electrode contact layer. A partition (to increase the contact time between the gas and the electrode and prevent the gas from leaving the gas chamber directly) is provided in the middle of the circular groove, its length being slightly less than the depth of the circular groove, 6-8 mm. A vent hole communicating with the groove is placed on each side of the partition. A through hole is provided in the middle of the electrolyte layer, and a corresponding through hole is provided in the middle of the sealing gasket, thus allowing the interior of the outer shell to communicate with each other, forming a cavity to contain the electrolyte. Through holes or screw holes for fixing screws are provided at the four corners of the negative electrode contact layer, electrolyte layer, and gas diffusion electrode contact layer.

[0052] The device is assembled in the following manner: (1) Rinse the hydrophobic carbon cloth several times with different washing solvents.

[0053] (2) According to the mass ratio of electrode material: conductive carbon: polyvinylidene fluoride X:(9~X):1, X=5~7, mix them together and mix them in a solvent for 12 hours to obtain a uniform gas diffusion electrode conductive slurry.

[0054] (3) The conductive paste is coated on the surface of the hydrophobic carbon cloth and dried in a vacuum oven at 80 degrees Celsius for 12 hours to obtain a gas diffusion electrode sheet.

[0055] (4) Assemble the gas diffusion electrode, zinc electrode, electrolyte, and outer shell (plexiglass shell layer) in the following order: negative electrode contact layer, zinc electrode, sealing gasket, electrolyte layer, sealing gasket, gas diffusion electrode and gas diffusion electrode contact layer, and inject electrolyte into the cavity formed inside to obtain the device.

[0056] In the above, the washing solvent in step (1) is water and ethanol.

[0057] In the above, the mixing in step (1) involves first grinding the mixture in an agate mortar and pestle, then transferring it to a stirable container and stirring it together with the solvent.

[0058] This device is used in the application of nitrogen dioxide catalysis, absorption and power generation in the atmospheric environment. Specifically, it is a device based on the electrode material (naphthylaminoquinone polymer) for the "direct capture-conversion power generation" of nitrogen oxides to capture, remove and convert nitrogen dioxide into energy.

[0059] Example 1 (1) Synthesis of naphthylaminoquinone polymer electrode materials: Weigh 0.24 g of 2,3-dichloro-1,4-naphthoquinone and 0.16 g of 1,5-diaminonaphthalene, place them in 35 mL of water and stir. React at 80 °C for 12 hours. After the reaction is complete, allow the temperature to cool to room temperature. Filter the product and wash it several times with water and ethanol until the solvent is clear and transparent. After vacuum drying at 80 °C, a gray-black powder is obtained. Its scanning electron microscope image is shown below. Figure 2 As shown, it exhibits an amorphous, sheet-like structure. The infrared characterization and N1s X-ray photoelectron spectroscopy of the dried gray-black powder and the raw materials used in its preparation are shown in the figures below. Figure 3 and Figure 4 As shown, this demonstrates the successful preparation of the material.

[0060] (2) Preparation of gas diffusion electrode sheet: (a) The electrode material (60 mg) prepared above was mixed with Ketjen black (30 mg) and polyvinylidene fluoride (10 mg) in a mass ratio of 6:3:1 and ground in an agate mortar.

[0061] (b) Add 400 μL of NMP and stir for 12 h to form a conductive slurry.

[0062] (c) The conductive paste is coated onto a clean hydrophobic carbon cloth using a coating machine. After drying, the electrode material thickness on the carbon cloth surface is 200 micrometers.

[0063] (3) Preparation of a nitrogen dioxide gas (NO2) absorption and power output device based on the "direct capture-conversion power generation" of organic nitrogen oxides: (a) Assemble the plexiglass forming the outer shell and the two sets of electrode plates and sealing rings in the following order: plexiglass plate No. 1 (negative electrode contact layer); zinc sheet electrode; sealing gasket; plexiglass plate No. 2 (electrolyte layer); sealing gasket; gas diffusion electrode plate; plexiglass plate No. 3 (gas diffusion electrode contact layer).

[0064] (b) Finally, the stacked layers are fixed together with screws.

[0065] (c) Finally, add 2 M zinc chloride electrolyte to the cavity inside the shell.

[0066] Images of the completed device (a direct capture-conversion power generation device for nitrogen oxides) are shown below. Figure 5 As shown.

[0067] Performance tests were conducted on a device that directly captures and converts nitrogen oxides at a concentration of ppm for power generation. The aforementioned nitrogen oxide "direct capture-conversion power generation" device was used at 2 mA / cm². 2 After discharging to 0.1 V at a current density, the battery was exposed to different concentrations of nitrogen dioxide atmosphere, specifically: 1 ppm, 10 ppm, 50 ppm, 100 ppm, 200 ppm, 500 ppm, and 1000 ppm. The voltage change was observed, and the results are as follows: Figure 6 As shown in the figure, the test results indicate that the battery potential gradually increases with time, and the higher the concentration of nitrogen oxides, the shorter the required time. In contrast, under a pure nitrogen atmosphere, the voltage eventually remains at a constant low voltage. These results demonstrate that the device exhibits excellent voltage response to a nitrogen dioxide atmosphere of 1 ppm.

[0068] from Figure 7 and Figure 8 It can be observed that after exposure to 200 ppm NO2 for different durations (3 min, 5 min, 10 min, 20 min, 30 min, 60 min, and 120 min), the discharge capacity of the battery gradually increases with time, the discharge current density increases, and the discharge capacity decreases accordingly. Furthermore, the discharge capacity also increases with increasing nitrogen dioxide concentration (1 ppm, 10 ppm, 50 ppm, 100 ppm, 200 ppm, 500 ppm, and 1000 ppm).

[0069] Example 2 This embodiment is basically the same as Example 1, except that step (1) is changed to prepare a different naphthylaminoquinone polymer electrode material. The specific steps are as follows: (1) Synthesis of naphthylaminoquinone polymer electrode materials: Weigh 0.24 g of 2,3-dichloro-1,4-naphthoquinone and 0.16 g of 1,5-diaminonaphthalene, place them in 35 mL of DMF, and react at 80 °C for 12 hours. After the reaction is complete, pour the hot reaction liquid into an ice-water mixture. Then filter the product and wash it several times with water and ethanol.

[0070] Compared with Example 1, the synthesis method of Example 2 produces a product with higher purity by reducing the temperature, which decreases the solubility and causes the naphthylaminoquinone polymer electrode material to precipitate from the DMF solution.

[0071] The nitrogen oxide "direct capture-conversion power generation" device finally assembled in this embodiment has basically the same performance as that in Embodiment 1, and will not be described in detail.

[0072] Example 3 This embodiment is basically the same as embodiment 1, except that step (2) is changed to prepare a different gas diffusion electrode sheet. The specific steps are as follows: (2) Preparation of gas diffusion electrode sheet: (a) The electrode material (60 mg) prepared in Example 1 was mixed with super P conductive carbon black (40 mg) and polyvinylidene fluoride (10 mg) in a mass ratio of 5:4:1 and ground in an agate mortar.

[0073] (b) Then add 400 μL of NMP and stir for 12 h to form a conductive slurry.

[0074] (c) The conductive paste was then coated onto a clean hydrophobic carbon cloth using a coating machine. After drying, the electrode material thickness on the carbon cloth surface was 600 micrometers.

[0075] The nitrogen oxide "direct capture-conversion power generation" device finally assembled in this embodiment has basically the same performance as that in Embodiment 1, and will not be described in detail.

[0076] Example 4 This embodiment is basically the same as embodiment 1, except that step (2) is changed to prepare a different gas diffusion electrode sheet. The specific steps are as follows: (2) Preparation of gas diffusion electrode sheet: (a) The electrode material (60 mg) prepared in Example 1 was mixed with Ketjen black (30 mg) and polyvinylidene fluoride (10 mg) in a mass ratio of 6:3:1 and ground in an agate mortar.

[0077] (b) Then add 400 μL of DMSO and stir for 12 h to form a conductive slurry.

[0078] (c) The conductive paste is coated onto a clean hydrophobic carbon cloth using a coating machine. After drying, the electrode material thickness on the carbon cloth surface is 200 micrometers.

[0079] The DMSO used in Example 4 is less toxic than NMP.

[0080] The nitrogen oxide "direct capture-conversion power generation" device finally assembled in this embodiment has basically the same performance as that in Embodiment 1, and will not be described in detail.

[0081] Example 5 This embodiment is basically the same as Embodiment 1, except that step (3) is changed to prepare a different nitrogen oxide "direct capture-conversion power generation" device. The specific steps are as follows: (3) Preparation of a nitrogen dioxide gas (NO2) absorption and power output device based on the "direct capture-conversion power generation" of organic nitrogen oxides: (a) Assemble the plexiglass forming the outer shell and the two sets of electrode plates and sealing rings in the following order: plexiglass plate No. 1; zinc electrode; sealing gasket; plexiglass plate No. 2; sealing gasket; gas diffusion electrode plate; plexiglass plate No. 3.

[0082] (b) Finally, they are secured together with screws.

[0083] (c) Finally, add 3 M zinc trifluoromethanesulfonate electrolyte to the cavity inside the outer shell.

[0084] The nitrogen oxide "direct capture-conversion power generation" device finally assembled in this embodiment has basically the same performance as that in Embodiment 1, and will not be described in detail.

[0085] Example 6 Cyclic stability and material stability of the nitrogen oxide "direct capture-conversion power generation" device under nitrogen dioxide atmosphere.

[0086] The nitrogen oxide "direct capture-conversion power generation" device from Example 1 was exposed to a nitrogen dioxide atmosphere of 200 ppm for 1 hour, followed by an exposure to 2 mA / cm². 2 Cyclic performance of discharge at current density, from Figure 9 As can be seen, the device has excellent stability. Furthermore, as... Figure 10 After the first discharge cycle and 200 cycles, the infrared spectrum remained almost unchanged, which also verified the stability of the electrode.

[0087] Figure 11 Further demonstration showed that when two devices from Example 1 were connected in series and placed in a nitrogen dioxide atmosphere of 200 ppm, at 1 mA / cm 2After discharging at a current density for 2 hours (including resting time; the operating mode is: discharge to 0.2 V, rest for 10 min to capture nitrogen dioxide, increase voltage, discharge again, and repeat this cycle), the device can significantly reduce the NO2 concentration in the environment (from 200.7 ppm to 9.6 ppm). In the non-discharge state, because the material on the gas diffusion electrode cannot form a reducing catalyst and therefore cannot reduce nitrogen dioxide, the concentration change is small; the observed concentration decrease mainly comes from the adsorption of materials in the environment.

[0088] Comparative Example 1 Performance comparison of pure carbon gas diffusion electrodes without naphthylaminoquinone polymers This embodiment is basically the same as embodiment 1, except that step (2) is changed to prepare a different gas diffusion electrode sheet. The specific steps are as follows: (a) Mix Ketjen black (90 mg) and polyvinylidene fluoride (10 mg) and grind them in an agate mortar.

[0089] (b) Add 400 μL of NMP and stir for 12 h to form a conductive slurry.

[0090] (c) The conductive paste is coated onto a clean hydrophobic carbon cloth using a coating machine. After drying, the electrode material thickness on the carbon cloth surface is 200 micrometers.

[0091] Figure 12 This study demonstrates the voltage variation of a nitrogen dioxide capture and power generation electrochemical device based on a pure carbon gas diffusion electrode at 200 ppm nitrogen dioxide, and its corresponding capacity at different discharge current densities. Although the voltage of the device increases, it fails to output usable capacity. (2 mA / cm²) 2 The capacity at current density is only 0.01 mAh / cm³. 2 .

[0092] Comparative Example 2 Performance comparison of tetraamino-p-benzoquinone gas diffusion electrodes This embodiment is basically the same as embodiment 1, except that step (2) is changed to prepare a different gas diffusion electrode sheet. The specific steps are as follows: (a) Tetraaminobenzoquinone (60 mg) was mixed with Ketjen black (30 mg) and polyvinylidene fluoride (10 mg) in a mass ratio of 6:3:1 and ground in an agate mortar.

[0093] (b) Add 400 μL of NMP and stir for 12 h to form a conductive slurry.

[0094] (c) The conductive paste is coated onto a clean hydrophobic carbon cloth using a coating machine. After drying, the electrode material thickness on the carbon cloth surface is 200 micrometers.

[0095] Figure 13 An electrochemical device for capturing nitrogen dioxide and generating electricity based on a tetraamino-p-benzoquinone gas diffusion electrode was demonstrated, which, after 1 hour of exposure to 200 ppm nitrogen dioxide, achieved a power output of 2 mA / cm². 2 The figure shows the change in cyclic discharge capacity at current density. It also shows that the device based on tetraaminop-benzoquinone exhibits poor capacity stability, with the released capacity gradually decreasing after several cycles.

[0096] In summary, this invention designs a device for absorbing and converting nitrogen dioxide at concentrations of ppm based on naphthylaminoquinone polymer materials into electrical energy. This device can absorb nitrogen dioxide at different ppm concentrations and convert it into electrical energy. It is small in size, low in cost, and can absorb low concentrations of nitrogen dioxide. This invention can be used in green, environmentally friendly, and inexpensive nitrogen dioxide absorption and treatment scenarios.

[0097] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A device for "direct capture-conversion power generation" of nitrogen oxides at a concentration of ppm, characterized in that, include: Zinc sheet electrode, electrolyte and gas diffusion electrode; The gas diffusion electrode is obtained by coating an electrode paste onto a hydrophobic carbon cloth; The electrode paste is formed by mixing electrode material, conductive carbon, and polyvinylidene fluoride in an organic solvent; The electrode material has a structure as shown in formula (I): Equation (I); In the formula, n ranges from 20 to 100.

2. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 1, characterized in that, The electrolyte is either an aqueous solution of zinc chloride or zinc trifluoromethanesulfonate. The concentration of the electrolyte is 0.5~3 M.

3. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 1, characterized in that, The electrode paste is coated onto hydrophobic carbon cloth and then vacuum dried to obtain the gas diffusion electrode. The vacuum drying temperature is 80℃ and the time is 12 hours.

4. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 1, characterized in that, The electrode paste is formed by mixing electrode materials, conductive carbon and polyvinylidene fluoride in an organic solvent at a mass ratio of X:(9~X):1, wherein the value of X is 5~7. The ratio of the mixture of electrode material, conductive carbon and polyvinylidene fluoride to organic solvent is 100 mg: 400 μL; The conductive carbon is Super P or Ketjen Black; The organic solvent is dimethyl sulfoxide or N-methylpyrrolidone.

5. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 1, characterized in that, The thickness of the electrode slurry in the gas diffusion electrode is 200~600 micrometers.

6. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 1, characterized in that, The electrode material is prepared by the following method: 2,3-Dichloro-1,4-naphthoquinone and aromatic amine were added to a solvent and heated to react. The electrode material was then obtained by centrifugation, washing and drying.

7. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 6, characterized in that, The aromatic amine is 1,5-diaminonaphthalene; 2,3-Dichloro-1,4-naphthoquinone reacts with 1,5-diaminonaphthalene in an equimolar ratio; The solvent is water or N,N'-dimethylformamide; The heating reaction was carried out at a temperature of 80°C for 12 hours.

8. The apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides according to claim 1, characterized in that, The device also includes a housing; The outer casing includes a negative electrode contact layer, an electrolyte layer, a gas diffusion electrode contact layer, and a sealing gasket, wherein the electrolyte layer and the sealing gasket have through holes. The device is constructed by stacking and fixing a negative electrode contact layer, a zinc sheet electrode, a sealing gasket, an electrolyte layer, a sealing gasket, a gas diffusion electrode, and a gas diffusion electrode contact layer. The electrolyte is injected into the casing of the device for "direct capture-conversion power generation" of nitrogen oxides.

9. The application of the apparatus for "direct capture-conversion power generation" of ppm concentration nitrogen oxides as described in any one of claims 1 to 8 in the capture and conversion power generation of nitrogen oxides.

10. The application according to claim 9, characterized in that, The device is exposed to a nitrogen dioxide atmosphere to capture, convert, and generate electricity from nitrogen dioxide.

Images