Preparation and application method of Ti4O7-based nanotube electrochemical anode film

Abstract

The invention relates to the technical field of electrochemistry, and discloses a preparation and application method of a Ti4O7-based nanotube electrochemical anode film.The preparation method comprises the following steps of porous titanium tube pretreatment, electrochemical oxidation treatment, cleaning treatment, calcination treatment and reduction treatment. A porous titanium tube is adopted as a base material, optimized electrochemical oxidation treatment is carried out, a uniform nanotube array precursor grows on the surface of the base material and the inner wall of a pore channel in situ under the conditions of specific electrolyte composition and constant pressure, and then precisely-controlled calcination and electrochemical reduction treatment are carried out, so that the nano-tube array is obtained. The method can effectively solve the problems that the film nanotube structure prepared by the traditional method is not uniform and the binding force with the matrix is poor, ensures that the prepared anode film has a regular nanotube channel and high mechanical strength, improves the stability of the film structure in long-term operation, and avoids structural failure.

Description

Technical Field

[0001] This invention relates to the field of electrochemical technology, specifically to a method for preparing and applying a Ti4O7-based nanotube electrochemical anode membrane. Background Technology

[0002] Electrochemistry is the science that studies the phenomenon of charged interfaces formed between two types of conductors and the changes that occur thereon.

[0003] Currently, several technical challenges remain in the preparation and application of Ti4O7-based electrocatalytic membranes. In terms of preparation, traditional methods such as high-temperature sintering reduction or anodic oxidation often result in Ti4O7 membranes with inhomogeneous nanotube array structures, easily collapsing tube walls, and poor adhesion to the substrate, leading to insufficient mechanical strength and susceptibility to structural failure during long-term operation. Furthermore, existing processes struggle to achieve Ti… 4+ Ti4OS to Ti 35+ While achieving efficient and controllable conversion, Ti4O7 membranes are prone to uneven oxygen vacancy distribution or excessive reduction to generate Ti5O9 impurities, affecting the electrocatalytic activity and stability of the membrane. In application, most Ti4O7 membranes have a dense planar structure, resulting in limited effective electroactive area and low mass transfer efficiency. This leads to high energy consumption when treating wastewater with low conductivity. Furthermore, traditional Ti4O7 electrodes are prone to passivation of active sites due to the adsorption of intermediate products when degrading high molecular weight or difficult-to-oxidize organic matter, causing current efficiency to decrease over time. Current technologies have not yet achieved a composite membrane structure with regular nanotube channels, high Ti4O7 phase purity, excellent mechanical strength, and long-term operational stability. It is also difficult to achieve both high-efficiency pollutant degradation and low energy consumption and anti-pollution characteristics.

[0004] Therefore, a method for preparing and applying Ti4O7-based nanotube electrochemical anode films is proposed to address the aforementioned technical deficiencies. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for preparing and applying Ti4O7-based nanotube electrochemical anode films, which solves the problems mentioned in the background technology, such as the easy passivation of active sites due to the adsorption of intermediate products and the decrease in current efficiency over time.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing and applying a Ti4O7-based nanotube electrochemical anolyte film, comprising the following steps: Step 1: Pre-treatment of porous titanium tubes. Select porous titanium tubes as the substrate and perform surface grinding, cleaning and chemical etching to remove surface stains and activate the surface of the titanium tubes. Step 2: Electrochemical oxidation treatment. The pretreated porous titanium tube is used as the anode, and cathode electrodes are set on its inner and outer sides respectively. It is placed in a specific electrolyte and electrochemical oxidation reaction is carried out under constant voltage conditions to form the initial nanotube structure. Step 3: Cleaning treatment. The porous titanium tube after electrochemical oxidation is immersed in an organic solvent to remove residual electrolytes and impurities on the surface. Step 4: Calcination treatment. The cleaned porous titanium tubes are placed in a high-temperature furnace and calcined at a controllable heating rate to transform the surface nanotube structure into a titanium dioxide nanotube array. Step 5: Reduction treatment. The calcined titanium dioxide nanotube array is used as the cathode and placed together with the auxiliary anode in a reducing electrolyte. Through electrochemical reduction reaction, titanium dioxide is converted into titanium suboxide, and finally Ti4O7-based nanotube electrochemical anode film is obtained. The porous titanium tube has a pore size of 1-6 μm, a porosity of 60%-80%, and a specific surface area of ​​4-6 m² / g; The electrolyte comprises ethylene glycol, ultrapure water, and sodium fluoride, wherein the volume fraction of ethylene glycol is 95%, the volume fraction of ultrapure water is 5%, and the mass fraction of sodium fluoride is 0.5%. The constant voltage condition is 20-50V, and the reaction time is 3-6h; The calcination temperature is 400-600℃, the calcination time is 2-4h, and the heating and cooling rates are both 3-5℃ / min; The reducing electrolyte contains ammonium sulfate and chloroplatinic acid, wherein the concentration of ammonium sulfate is 1 mol / L and the concentration of chloroplatinic acid is 0.5 mmol / L; The current density of the reduction treatment is 2-6 mA / cm², and the reaction time is 10-30 min.

[0007] Preferably, the preprocessing in step one includes the following sub-steps: First, sand both sides of the porous titanium tube with sandpaper until the surface is smooth, shiny, and has a metallic luster. Secondly, rinse both sides of the polished titanium tube three times with deionized water, and then soak it in a 5% sodium hydroxide solution at 90°C for 2 hours to thoroughly remove surface stains. Finally, the titanium tube treated with alkali was rinsed with deionized water and then immersed in a 4% (w / w) boiling oxalic acid solution for etching for 2.5 hours. After etching, it was rinsed repeatedly with deionized water to remove any remaining titanium oxalate residue.

[0008] The porous titanium tube has the following dimensions: inner diameter 2.4cm, outer diameter 3cm, wall thickness 1cm, and length 35cm. The sanding process uses 400-600 grit sandpaper with a sanding pressure of 0.1-0.3 MPa.

[0009] Preferably, in the pretreatment of step one, the mass fraction of sodium hydroxide solution is 5%±0.5%, the mass fraction of oxalic acid solution is 4%±0.5%, and the temperature of oxalic acid solution is maintained at boiling. Each rinse with deionized water takes 1-2 minutes, and the total rinsing time is not less than 5 minutes. The porous titanium tube is made of industrial pure titanium with a titanium content of not less than 99.5%. The porosity is determined by mercury intrusion porosimetry to ensure uniform pore size distribution.

[0010] Preferably, in the electrochemical oxidation process of step two, the cathode electrode includes a thin stainless steel tube and a thick stainless steel tube. The stainless steel tube has a diameter of 4mm and a length of 35cm and is placed inside the center of the porous titanium tube. The stainless steel tube has an inner diameter of 5cm, an outer diameter of 5.2cm, a wall thickness of 2mm, and a length of 35cm, and is placed on the outside of the porous titanium tube. The distance between the porous titanium tube and the cathode electrode is 20mm±2mm, and it is connected to a DC power supply through a wire. The positive terminal is connected to the porous titanium tube, and the negative terminal is connected to the stainless steel electrode. The pH of the electrolyte is adjusted to 3-5, using hydrochloric acid or sodium hydroxide for fine-tuning to ensure the stability of the electrochemical reaction.

[0011] Preferably, the electrolyte contains 0.5% ± 0.1% sodium fluoride by mass, and the electrolyte needs to be filtered through a 0.22 μm microporous membrane before use to remove suspended particles; The specific parameters of the constant voltage condition are: initial voltage 20V, gradually increased to 50V, and the voltage increase rate is 5V / min; The electrochemical oxidation reaction is carried out at room temperature, and the electrolyte is stirred with a magnetic stirrer at a speed of 100-200 r / min during the reaction to ensure uniform mass transfer.

[0012] Preferably, in the cleaning process of step three, the organic solvent is anhydrous ethanol, the soaking time is 10-40 min, and ultrasonic assisted cleaning is performed for 1 min every 5 min during the soaking process; After cleaning, the porous titanium tube needs to be dried in an oven at 50-60℃ for 30 minutes until there is no residual solvent on the surface; The purity of the anhydrous ethanol is not less than 99.7%, and the amount used for each cleaning is 3-5 times the volume of the titanium tube.

[0013] Preferably, the calcination process in step four is carried out in a muffle furnace, with an air atmosphere and an oxygen volume fraction of 21% ± 5%. During the calcination process, the morphology of the nanotube array is monitored by scanning electron microscopy to ensure that the tubular structure is continuous and uniformly distributed. The titanium dioxide nanotube array has a diameter of 50-100 nm, a length of 1-2 μm, and the array orientation is perpendicular to the surface of the titanium tube.

[0014] Preferably, in the reduction process of step five, the auxiliary anode is a Ti / Ti4O7 electrode prepared by plasma spraying, the size of which matches the porous titanium tube; The pH of the reducing electrolyte is maintained at 2-3 and adjusted using sulfuric acid; The electrochemical reduction reaction is carried out at room temperature, and the electrode must be rinsed three times with deionized water after the reaction and stored under a nitrogen atmosphere to prevent oxidation.

[0015] Preferably, the surface morphology of the finally obtained Ti4O7-based nanotube electrochemical anolyte film is a dense porous tubular structure, and X-ray diffraction analysis shows that the main phase is Ti4O7, and the oxygen vacancy concentration is 10-15 at% as determined by XPS. The oxygen evolution potential of the anolyte is 2.5-3.1V, and the electrochemical active area is calculated to be 5-10 times that of a conventional planar electrode by cyclic voltammetry. The mechanical strength of the anode membrane is tested by a three-point bending test, with a bending strength of not less than 200 MPa and an estimated service life of more than 1000 hours.

[0016] Preferably, it includes the following steps: Application Step 1: Construct an electrochemical reactor, using a Ti4O7-based nanotube electrochemical anolyte as the anode, with a stainless steel cathode placed in the center, and the outer wall of the reactor being made of plexiglass, forming a tubular membrane reactor; Application Step 2: Pump the organic wastewater into the reactor, control the wastewater flow rate at 0.5-2 L / min, and adjust the influent pH value to 3-11 to adapt to different water qualities; Application Step 3: Apply DC power, connect the anode and cathode to the positive and negative terminals respectively, set the voltage to 3-5V, the current density to 5-15mA / cm², and the reaction time to 20-60min; Application Step 4: Wastewater is circulated in the reactor using a cross-flow filtration method, and the permeate flows out from the side wall of the reactor. Samples of the effluent after electrochemical degradation are taken for analysis. The organic wastewater includes carbamate pesticide wastewater, in which the initial concentrations of typical pollutants, carbofuran and carbaryl, are 10-100 mg / L. The application method achieves a removal rate of 90%-96% for organic pollutants and a total organic carbon removal rate of 70%-80%, while consuming 30%-50% less energy than traditional electrochemical methods. The reactor operates at room temperature and requires no chemical reagents, thus achieving green processing.

[0017] Compared with the prior art, the present invention provides a method for preparing and applying Ti4O7-based nanotube electrochemical anode films, which has the following beneficial effects: 1. In this invention, during the preparation of Ti4O7-based nanotube electrochemical anode film, porous titanium tubes are used as the substrate and optimized electrochemical oxidation treatment is performed. Under specific electrolyte composition and constant voltage conditions, uniform nanotube array precursors are grown in situ on the substrate surface and the inner wall of the pores. After precise control of calcination and electrochemical reduction treatment, the problems of uneven nanotube structure and poor bonding force with the substrate in the film prepared by traditional methods can be effectively solved. This ensures that the prepared anode film has regular nanotube channels and high mechanical strength, improves the stability of the film structure in long-term operation, and avoids structural failure.

[0018] 2. In this invention, during the transformation of the Ti4O7 phase, by precisely controlling the calcination temperature, atmosphere, and the current density, time, and electrolyte environment of the subsequent electrochemical reduction, the efficient and controllable transformation of titanium dioxide nanotubes into high-purity Ti4O7 phase is achieved. This effectively suppresses the formation of the Ti5O9 impurity phase, resulting in a final anode film with high Ti4O7 phase purity and suitable oxygen vacancy concentration. This solves the problem of uneven oxygen vacancy distribution or excessive reduction in traditional processes, thereby improving the electrocatalytic activity and conductivity of the anode film.

[0019] 3. In this invention, the prepared Ti4O7-based nanotube electrochemical anode membrane uniquely combines the through-pores of porous titanium tube substrate, the large specific surface area of ​​nanotube array structure, and the high conductivity of Ti4O7 material. When applied to construct a tubular membrane electrochemical reactor for treating organic wastewater, the membrane itself has both electrode catalytic function and filtration separation function, enabling forced mass transfer of wastewater within the membrane channels. This effectively solves the problems of limited effective electroactive area and low mass transfer efficiency of traditional flat plate electrodes, thereby improving the degradation efficiency of organic pollutants and reducing energy consumption.

[0020] 4. In this invention, when using the Ti4O7-based nanotube electrochemical anode membrane for organic wastewater treatment, by adopting a cross-flow filtration operation mode and optimizing the applied voltage and current density operating parameters, organic pollutants are efficiently degraded. At the same time, the strong oxidizing free radicals generated on the surface of the nanotube structure can decompose intermediate products in a timely manner, and the fluid flushing effect can effectively reduce the adsorption and accumulation of pollutants on the active sites. This solves the problem that traditional electrodes are prone to passivation of active sites due to the adsorption of intermediate products, giving the anode membrane excellent anti-fouling performance and long-term operational stability, and maintaining high current efficiency. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: A method for preparing and applying a Ti4O7-based nanotube electrochemical anolyte includes the following steps: Step 1: Pre-treatment of porous titanium tubes. Select porous titanium tubes as the substrate and perform surface grinding, cleaning and chemical etching to remove surface stains and activate the surface of the titanium tubes. Step 2: Electrochemical oxidation treatment. The pretreated porous titanium tube is used as the anode, and cathode electrodes are set on its inner and outer sides respectively. It is placed in a specific electrolyte and electrochemical oxidation reaction is carried out under constant voltage conditions to form the initial nanotube structure. Step 3: Cleaning treatment. The porous titanium tube after electrochemical oxidation is immersed in an organic solvent to remove residual electrolytes and impurities on the surface. Step 4: Calcination treatment. The cleaned porous titanium tubes are placed in a high-temperature furnace and calcined at a controllable heating rate to transform the surface nanotube structure into a titanium dioxide nanotube array. Step 5: Reduction treatment. The calcined titanium dioxide nanotube array is used as the cathode and placed together with the auxiliary anode in a reducing electrolyte. Through electrochemical reduction reaction, titanium dioxide is converted into titanium suboxide, and finally Ti4O7-based nanotube electrochemical anode film is obtained. The porous titanium tube has a pore size of 1μm, a porosity of 60%, and a specific surface area of ​​4m² / g. The electrolyte contains ethylene glycol, ultrapure water, and sodium fluoride, wherein the volume fraction of ethylene glycol is 95%, the volume fraction of ultrapure water is 5%, and the mass fraction of sodium fluoride is 0.5%. The constant voltage condition was 20V, and the reaction time was 3 hours. The calcination temperature was 400℃, the calcination time was 2h, and the heating and cooling rates were both 3℃ / min. The reducing electrolyte contains ammonium sulfate and chloroplatinic acid, wherein the concentration of ammonium sulfate is 1 mol / L and the concentration of chloroplatinic acid is 0.5 mmol / L; The reduction treatment current density was 2 mA / cm², and the reaction time was 10 min. Step 1 preprocessing includes the following sub-steps: First, sand both sides of the porous titanium tube with sandpaper until the surface is smooth, shiny, and has a metallic luster. Secondly, rinse both sides of the polished titanium tube three times with deionized water, and then soak it in a 5% sodium hydroxide solution at 90°C for 2 hours to thoroughly remove surface stains. Finally, the titanium tube treated with alkali was rinsed with deionized water and then immersed in a 4% (w / w) boiling oxalic acid solution for etching for 2.5 hours. After etching, it was rinsed repeatedly with deionized water to remove any remaining titanium oxalate residue.

[0023] The dimensions of the porous titanium tube are: inner diameter 2.4cm, outer diameter 3cm, wall thickness 1cm, and length 35cm. Sanding was performed using 400-grit sandpaper at a pressure of 0.1 MPa. In the pretreatment of step one, the mass fraction of sodium hydroxide solution is 5%±0.5%, the mass fraction of oxalic acid solution is 4%±0.5%, and the temperature of oxalic acid solution is maintained at boiling. Each rinse with deionized water should last 1 minute, and the total rinsing time should not be less than 5 minutes. The porous titanium tube is made of industrial pure titanium with a titanium content of not less than 99.5%. The porosity is determined by mercury intrusion porosimetry to ensure uniform pore size distribution. In the electrochemical oxidation process of step two, the cathode electrode includes a thin stainless steel tube and a thick stainless steel tube. A stainless steel tube with a diameter of 4mm and a length of 35cm is placed inside the center of a porous titanium tube. A stainless steel tube with an inner diameter of 5cm, an outer diameter of 5.2cm, a wall thickness of 2mm, and a length of 35cm is placed on the outside of a porous titanium tube. The distance between the porous titanium tube and the cathode electrode is 20mm±2mm, and it is connected to a DC power supply through a wire. The positive terminal is connected to the porous titanium tube, and the negative terminal is connected to the stainless steel electrode. The pH of the electrolyte is adjusted to 3 using hydrochloric acid or sodium hydroxide to ensure the stability of the electrochemical reaction. The electrolyte contains 0.5% ± 0.1% sodium fluoride by mass, and the electrolyte must be filtered through a 0.22 μm microporous membrane before use to remove suspended particles. The specific parameters for the constant voltage condition are: initial voltage 20V, gradually increased to 50V, and the voltage increase rate is 5V / min; The electrochemical oxidation reaction was carried out at room temperature, and the electrolyte was stirred at 100 r / min using a magnetic stirrer during the reaction to ensure uniform mass transfer. In the cleaning process of step three, the organic solvent is anhydrous ethanol, the soaking time is 10 minutes, and ultrasonic assisted cleaning is performed for 1 minute every 5 minutes during the soaking process. After cleaning, the porous titanium tube needs to be dried in a 50°C oven for 30 minutes until there is no residual solvent on the surface; The purity of anhydrous ethanol is not less than 99.7%, and the amount used for each cleaning is three times the volume of the titanium tube; The calcination process in step four is carried out in a muffle furnace under an air atmosphere with an oxygen volume fraction of 21% ± 5%. During the calcination process, the morphology of the nanotube array was monitored by scanning electron microscopy to ensure that the tubular structure was continuous and uniformly distributed. The titanium dioxide nanotube array has a diameter of 50 nm, a length of 1 μm, and the array orientation is perpendicular to the surface of the titanium tube. In the reduction process of step five, the auxiliary anode is a Ti / Ti4O7 electrode prepared by plasma spraying, the size of which matches the porous titanium tube. The pH of the reducing electrolyte is maintained at 2 and adjusted using sulfuric acid; The electrochemical reduction reaction is carried out at room temperature, and the electrode must be rinsed three times with deionized water after the reaction and stored under a nitrogen atmosphere to prevent oxidation. The final Ti4O7-based nanotube electrochemical anolyte film exhibits a dense, porous tubular structure. X-ray diffraction analysis revealed that the main phase is Ti4O7, and the oxygen vacancy concentration, as determined by XPS, is 10 at%. The oxygen evolution potential of the anolyte is 2.5V, and the electrochemical active area is calculated to be 5 times that of the conventional planar electrode by cyclic voltammetry. The mechanical strength of the anode membrane is tested by a three-point bending test, with a bending strength of not less than 200MPa and an estimated service life of more than 1000h. Specifically, the following steps are included: Application Step 1: Construct an electrochemical reactor, using a Ti4O7-based nanotube electrochemical anolyte as the anode, with a stainless steel cathode placed in the center, and the outer wall of the reactor being made of plexiglass, forming a tubular membrane reactor; Application Step 2: Pump the organic wastewater into the reactor, control the wastewater flow rate at 0.5 L / min, and adjust the influent pH value to 3 to adapt to different water qualities; Application Step 3: Apply DC power, connect the anode and cathode to the positive and negative terminals respectively, set the voltage to 3V, the current density to 5mA / cm², and the reaction time to 20min; Application Step 4: Wastewater is circulated in the reactor using a cross-flow filtration method, and the permeate flows out from the side wall of the reactor. Samples of the effluent after electrochemical degradation are taken for analysis. Organic wastewater includes carbamate pesticide wastewater, with typical pollutants such as carbofuran and carbaryl having an initial concentration of 10 mg / L. The applied method achieves a 90% removal rate for organic pollutants and a 70% removal rate for total organic carbon, while consuming 30% less energy than traditional electrochemical methods. The reactor operates at room temperature and requires no chemical reagents, achieving green treatment.

[0024] Example 2: A method for preparing and applying a Ti4O7-based nanotube electrochemical anolyte film, comprising the following steps: Step 1: Pre-treatment of porous titanium tubes. Select porous titanium tubes as the substrate and perform surface grinding, cleaning and chemical etching to remove surface stains and activate the surface of the titanium tubes. Step 2: Electrochemical oxidation treatment. The pretreated porous titanium tube is used as the anode, and cathode electrodes are set on its inner and outer sides respectively. It is placed in a specific electrolyte and electrochemical oxidation reaction is carried out under constant voltage conditions to form the initial nanotube structure. Step 3: Cleaning treatment. The porous titanium tube after electrochemical oxidation is immersed in an organic solvent to remove residual electrolytes and impurities on the surface. Step 4: Calcination treatment. The cleaned porous titanium tubes are placed in a high-temperature furnace and calcined at a controllable heating rate to transform the surface nanotube structure into a titanium dioxide nanotube array. Step 5: Reduction treatment. The calcined titanium dioxide nanotube array is used as the cathode and placed together with the auxiliary anode in a reducing electrolyte. Through electrochemical reduction reaction, titanium dioxide is converted into titanium suboxide, and finally Ti4O7-based nanotube electrochemical anode film is obtained. The porous titanium tube has a pore size of 3μm, a porosity of 70%, and a specific surface area of ​​5m² / g. The electrolyte contains ethylene glycol, ultrapure water, and sodium fluoride, wherein the volume fraction of ethylene glycol is 95%, the volume fraction of ultrapure water is 5%, and the mass fraction of sodium fluoride is 0.5%. The constant voltage condition was 40V, and the reaction time was 4 hours. The calcination temperature was 500℃, the calcination time was 3h, and the heating and cooling rates were both 4℃ / min. The reducing electrolyte contains ammonium sulfate and chloroplatinic acid, wherein the concentration of ammonium sulfate is 1 mol / L and the concentration of chloroplatinic acid is 0.5 mmol / L; The reduction treatment current density was 4 mA / cm², and the reaction time was 20 min. Step 1 preprocessing includes the following sub-steps: First, sand both sides of the porous titanium tube with sandpaper until the surface is smooth, shiny, and has a metallic luster. Secondly, rinse both sides of the polished titanium tube three times with deionized water, and then soak it in a 5% sodium hydroxide solution at 90°C for 2 hours to thoroughly remove surface stains. Finally, the titanium tube treated with alkali was rinsed with deionized water and then immersed in a 4% (w / w) boiling oxalic acid solution for etching for 2.5 hours. After etching, it was rinsed repeatedly with deionized water to remove any remaining titanium oxalate residue.

[0025] The dimensions of the porous titanium tube are: inner diameter 2.4cm, outer diameter 3cm, wall thickness 1cm, and length 35cm. Sanding was performed using 500-grit sandpaper at a pressure of 0.2 MPa. In the pretreatment of step one, the mass fraction of sodium hydroxide solution is 5%±0.5%, the mass fraction of oxalic acid solution is 4%±0.5%, and the temperature of oxalic acid solution is maintained at boiling. Each rinse with deionized water should take 1.5 minutes, and the total rinsing time should not be less than 5 minutes. The porous titanium tube is made of industrial pure titanium with a titanium content of not less than 99.5%. The porosity is determined by mercury intrusion porosimetry to ensure uniform pore size distribution. In the electrochemical oxidation process of step two, the cathode electrode includes a thin stainless steel tube and a thick stainless steel tube. A stainless steel tube with a diameter of 4mm and a length of 35cm is placed inside the center of a porous titanium tube. A stainless steel tube with an inner diameter of 5cm, an outer diameter of 5.2cm, a wall thickness of 2mm, and a length of 35cm is placed on the outside of a porous titanium tube. The distance between the porous titanium tube and the cathode electrode is 20mm±2mm, and it is connected to a DC power supply through a wire. The positive terminal is connected to the porous titanium tube, and the negative terminal is connected to the stainless steel electrode. The pH of the electrolyte is adjusted to 4 using hydrochloric acid or sodium hydroxide to ensure the stability of the electrochemical reaction. The electrolyte contains 0.5% ± 0.1% sodium fluoride by mass, and the electrolyte must be filtered through a 0.22 μm microporous membrane before use to remove suspended particles. The specific parameters for the constant voltage condition are: initial voltage 20V, gradually increased to 50V, and the voltage increase rate is 5V / min; The electrochemical oxidation reaction was carried out at room temperature, and the electrolyte was stirred at 150 r / min using a magnetic stirrer during the reaction to ensure uniform mass transfer. In the cleaning process of step three, the organic solvent is anhydrous ethanol, the soaking time is 30 minutes, and ultrasonic assisted cleaning is performed for 1 minute every 5 minutes during the soaking process. After cleaning, the porous titanium tube needs to be dried in a 55°C oven for 30 minutes until there is no residual solvent on the surface. The purity of anhydrous ethanol is not less than 99.7%, and the amount used for each cleaning is 4 times the volume of the titanium tube; The calcination process in step four is carried out in a muffle furnace under an air atmosphere with an oxygen volume fraction of 21% ± 5%. During the calcination process, the morphology of the nanotube array was monitored by scanning electron microscopy to ensure that the tubular structure was continuous and uniformly distributed. The titanium dioxide nanotube array has a diameter of 70 nm, a length of 1.5 μm, and the array orientation is perpendicular to the surface of the titanium tube. In the reduction process of step five, the auxiliary anode is a Ti / Ti4O7 electrode prepared by plasma spraying, the size of which matches the porous titanium tube. The pH of the reducing electrolyte was maintained at 2.5 and adjusted using sulfuric acid. The electrochemical reduction reaction is carried out at room temperature, and the electrode must be rinsed three times with deionized water after the reaction and stored under a nitrogen atmosphere to prevent oxidation. The final Ti4O7-based nanotube electrochemical anolyte film exhibited a dense, porous tubular structure. X-ray diffraction analysis revealed that the main phase was Ti4O7, and the oxygen vacancy concentration, as determined by XPS, was 13 at%. The oxygen evolution potential of the anolyte is 2.8V, and the electrochemical active area is calculated to be 8 times that of the conventional planar electrode by cyclic voltammetry. The mechanical strength of the anode membrane is tested by a three-point bending test, with a bending strength of not less than 200MPa and an estimated service life of more than 1000h. Specifically, the following steps are included: Application Step 1: Construct an electrochemical reactor, using a Ti4O7-based nanotube electrochemical anolyte as the anode, with a stainless steel cathode placed in the center, and the outer wall of the reactor being made of plexiglass, forming a tubular membrane reactor; Application Step 2: Pump the organic wastewater into the reactor, control the wastewater flow rate at 1L / min, and adjust the influent pH value to 7 to adapt to different water qualities; Application Step 3: Apply DC power, connect the anode and cathode to the positive and negative terminals respectively, set the voltage to 4V, the current density to 10mA / cm², and the reaction time to 40min; Application Step 4: Wastewater is circulated in the reactor using a cross-flow filtration method, and the permeate flows out from the side wall of the reactor. Samples of the effluent after electrochemical degradation are taken for analysis. Organic wastewater includes carbamate pesticide wastewater, with typical pollutants such as carbofuran and carbaryl having an initial concentration of 60 mg / L. The applied method achieves a 93% removal rate for organic pollutants and a 75% removal rate for total organic carbon, while consuming 40% less energy than traditional electrochemical methods. The reactor operates at room temperature and requires no chemical reagents, achieving green treatment.

[0026] Example 3: A method for preparing and applying a Ti4O7-based nanotube electrochemical anolyte film, comprising the following steps: Step 1: Pre-treatment of porous titanium tubes. Select porous titanium tubes as the substrate and perform surface grinding, cleaning and chemical etching to remove surface stains and activate the surface of the titanium tubes. Step 2: Electrochemical oxidation treatment. The pretreated porous titanium tube is used as the anode, and cathode electrodes are set on its inner and outer sides respectively. It is placed in a specific electrolyte and electrochemical oxidation reaction is carried out under constant voltage conditions to form the initial nanotube structure. Step 3: Cleaning treatment. The porous titanium tube after electrochemical oxidation is immersed in an organic solvent to remove residual electrolytes and impurities on the surface. Step 4: Calcination treatment. The cleaned porous titanium tubes are placed in a high-temperature furnace and calcined at a controllable heating rate to transform the surface nanotube structure into a titanium dioxide nanotube array. Step 5: Reduction treatment. The calcined titanium dioxide nanotube array is used as the cathode and placed together with the auxiliary anode in a reducing electrolyte. Through electrochemical reduction reaction, titanium dioxide is converted into titanium suboxide, and finally Ti4O7-based nanotube electrochemical anode film is obtained. The porous titanium tube has a pore size of 6μm, a porosity of 60%, and a specific surface area of ​​4m² / g. The electrolyte contains ethylene glycol, ultrapure water, and sodium fluoride, wherein the volume fraction of ethylene glycol is 95%, the volume fraction of ultrapure water is 5%, and the mass fraction of sodium fluoride is 0.5%. The constant voltage condition was 20V, and the reaction time was 3 hours. The calcination temperature was 400℃, the calcination time was 2h, and the heating and cooling rates were both 3℃ / min. The reducing electrolyte contains ammonium sulfate and chloroplatinic acid, wherein the concentration of ammonium sulfate is 1 mol / L and the concentration of chloroplatinic acid is 0.5 mmol / L; The reduction treatment current density was 2 mA / cm², and the reaction time was 10 min. Step 1 preprocessing includes the following sub-steps: First, sand both sides of the porous titanium tube with sandpaper until the surface is smooth, shiny, and has a metallic luster. Secondly, rinse both sides of the polished titanium tube three times with deionized water, and then soak it in a 5% sodium hydroxide solution at 90°C for 2 hours to thoroughly remove surface stains. Finally, the titanium tube treated with alkali was rinsed with deionized water and then immersed in a 4% (w / w) boiling oxalic acid solution for etching for 2.5 hours. After etching, it was rinsed repeatedly with deionized water to remove any remaining titanium oxalate residue.

[0027] The dimensions of the porous titanium tube are: inner diameter 2.4cm, outer diameter 3cm, wall thickness 1cm, and length 35cm. Sanding was performed using 400-grit sandpaper at a pressure of 0.1 MPa. In the pretreatment of step one, the mass fraction of sodium hydroxide solution is 5%±0.5%, the mass fraction of oxalic acid solution is 4%±0.5%, and the temperature of oxalic acid solution is maintained at boiling. Each rinse with deionized water should last 1 minute, and the total rinsing time should not be less than 5 minutes. The porous titanium tube is made of industrial pure titanium with a titanium content of not less than 99.5%. The porosity is determined by mercury intrusion porosimetry to ensure uniform pore size distribution. In the electrochemical oxidation process of step two, the cathode electrode includes a thin stainless steel tube and a thick stainless steel tube. A stainless steel tube with a diameter of 4mm and a length of 35cm is placed inside the center of a porous titanium tube. A stainless steel tube with an inner diameter of 5cm, an outer diameter of 5.2cm, a wall thickness of 2mm, and a length of 35cm is placed on the outside of a porous titanium tube. The distance between the porous titanium tube and the cathode electrode is 20mm±2mm, and it is connected to a DC power supply through a wire. The positive terminal is connected to the porous titanium tube, and the negative terminal is connected to the stainless steel electrode. The pH of the electrolyte is adjusted to 3 using hydrochloric acid or sodium hydroxide to ensure the stability of the electrochemical reaction. The electrolyte contains 0.5% ± 0.1% sodium fluoride by mass, and the electrolyte must be filtered through a 0.22 μm microporous membrane before use to remove suspended particles. The specific parameters for the constant voltage condition are: initial voltage 20V, gradually increased to 50V, and the voltage increase rate is 5V / min; The electrochemical oxidation reaction was carried out at room temperature, and the electrolyte was stirred at 200 r / min using a magnetic stirrer during the reaction to ensure uniform mass transfer. In the cleaning process of step three, the organic solvent is anhydrous ethanol, the soaking time is 10 minutes, and ultrasonic assisted cleaning is performed for 1 minute every 5 minutes during the soaking process. After cleaning, the porous titanium tube needs to be dried in a 50°C oven for 30 minutes until there is no residual solvent on the surface; The purity of anhydrous ethanol is not less than 99.7%, and the amount used for each cleaning is three times the volume of the titanium tube; The calcination process in step four is carried out in a muffle furnace under an air atmosphere with an oxygen volume fraction of 21% ± 5%. During the calcination process, the morphology of the nanotube array was monitored by scanning electron microscopy to ensure that the tubular structure was continuous and uniformly distributed. The titanium dioxide nanotube array has a diameter of 50 nm, a length of 1 μm, and the array orientation is perpendicular to the surface of the titanium tube. In the reduction process of step five, the auxiliary anode is a Ti / Ti4O7 electrode prepared by plasma spraying, the size of which matches the porous titanium tube. The pH of the reducing electrolyte is maintained at 2 and adjusted using sulfuric acid; The electrochemical reduction reaction is carried out at room temperature, and the electrode must be rinsed three times with deionized water after the reaction and stored under a nitrogen atmosphere to prevent oxidation. The final Ti4O7-based nanotube electrochemical anolyte film exhibits a dense, porous tubular structure. X-ray diffraction analysis revealed that the main phase is Ti4O7, and the oxygen vacancy concentration, as determined by XPS, is 10 at%. The oxygen evolution potential of the anolyte is 2.5V, and the electrochemical active area is calculated to be 5 times that of the conventional planar electrode by cyclic voltammetry. The mechanical strength of the anode membrane is tested by a three-point bending test, with a bending strength of not less than 200MPa and an estimated service life of more than 1000h. Specifically, the following steps are included: Application Step 1: Construct an electrochemical reactor, using a Ti4O7-based nanotube electrochemical anolyte as the anode, with a stainless steel cathode placed in the center, and the outer wall of the reactor being made of plexiglass, forming a tubular membrane reactor; Application Step 2: Pump the organic wastewater into the reactor, control the wastewater flow rate at 0.5 L / min, and adjust the influent pH value to 3 to adapt to different water qualities; Application Step 3: Apply DC power, connect the anode and cathode to the positive and negative terminals respectively, set the voltage to 3V, the current density to 5mA / cm², and the reaction time to 20min; Application Step 4: Wastewater is circulated in the reactor using a cross-flow filtration method, and the permeate flows out from the side wall of the reactor. Samples of the effluent after electrochemical degradation are taken for analysis. Organic wastewater includes carbamate pesticide wastewater, with typical pollutants such as carbofuran and carbaryl having an initial concentration of 10 mg / L. The applied method achieves a 90% removal rate for organic pollutants and a 70% removal rate for total organic carbon, while consuming 30% less energy than traditional electrochemical methods. The reactor operates at room temperature and requires no chemical reagents, achieving green treatment.

[0028] Comparative Example 1: The difference between this comparative example and Example 1 is that in the pretreatment step one of this comparative example, the porous titanium tube was not etched with oxalic acid solution, but only cleaned with alkaline solution.

[0029] Comparative Example 2 differs from Example 2 in that the electrolyte used in step two of the electrochemical oxidation treatment in this comparative example does not contain sodium fluoride.

[0030] Comparative Example 3 differs from Example 3 in that: in step four, no calcination treatment was performed in this comparative example; instead, reduction treatment was performed directly after electrochemical oxidation.

[0031] Comparative Example 4 differs from Example 3 in that, in the reduction process of step five, the electrochemical reduction method is replaced by a high-temperature hydrogen reduction method.

[0032] The performance of the Ti4O7-based nanotube electrochemical anolyte films prepared in Examples 1-3 and Comparative Examples 1-4 was tested. The test items and methods are as follows: The purity of the Ti4O7 phase was tested using an X-ray diffractometer with a scanning range of 10°-80°. The intensity integral area ratio of the Ti4O7 characteristic peak to that of all titanium oxide characteristic peaks in the diffraction pattern was calculated. The oxygen evolution potential was tested using a three-electrode system, with the prepared anode as the working electrode, the saturated calomel electrode as the reference electrode, and the platinum sheet as the counter electrode. The potential was scanned to the current density of 1 mA / cm² in a 0.5 mol / L sodium sulfate solution using a linear sweep voltammetry method. The degradation efficiency of organic pollutants was tested in a self-made tubular electrochemical reactor. The prepared anode was used as the membrane electrode, and a methylene blue solution with an initial concentration of 50 mg / L was used as the target pollutant. The reaction was carried out for 60 minutes under a current density of 10 mA / cm². The residual concentration of the solution was measured using a UV-Vis spectrophotometer, and the removal rate was calculated. Accelerated life testing was conducted in a 0.5 mol / L sodium sulfate solution with enhanced electrolysis at a constant current density of 100 mA / cm², and the time required for the anode membrane voltage to rise to twice its initial value was recorded.

[0033] The test data of the Ti4O7-based nanotube electrochemical anode films prepared in Examples 1-3 and Comparative Examples 1-4 are recorded in the table below: By comparing and analyzing the data in the table, it can be seen that the Ti4O7-based nanotube electrochemical anode films prepared using the processes in Examples 1-3 are significantly superior to those prepared using the processes in Comparative Examples 1-4 in terms of phase purity, electrocatalytic activity, pollutant degradation efficiency, and service life. This indicates that in the preparation process of the Ti4O7-based nanotube electrochemical anode film, by using porous titanium tubes as the substrate and performing optimized electrochemical oxidation treatment, uniform nanotube array precursors are grown in situ on the substrate surface and the inner wall of the pores under specific electrolyte composition and constant voltage conditions. Then, through precisely controlled calcination and electrochemical reduction treatment, the anode film can achieve... This method effectively solves the problems of uneven nanotube structure and poor adhesion to the substrate in traditionally prepared films, ensuring that the prepared anode film has regular nanotube channels and high mechanical strength. This improves the stability of the film structure during long-term operation and avoids structural failure. During the Ti4O7 phase transformation process, by precisely controlling the calcination temperature, atmosphere, and subsequent electrochemical reduction current density, time, and electrolyte environment, efficient and controllable transformation of titanium dioxide nanotubes to high-purity Ti4O7 phase is achieved. This effectively suppresses the formation of Ti5O9 impurity phases, resulting in a final anode film with high Ti4O7 phase purity and suitable oxygen content. The vacancy concentration addresses the problem of uneven oxygen vacancy distribution or excessive reduction in traditional processes, thereby improving the electrocatalytic activity and conductivity of the anode membrane. The prepared Ti4O7-based nanotube electrochemical anode membrane uniquely combines the interconnected channels of porous titanium tube substrates, the large specific surface area of ​​nanotube array structures, and the high conductivity of Ti4O7 material. When applied to construct tubular membrane electrochemical reactors for treating organic wastewater, the membrane itself possesses both electrode catalytic and filtration functions, enabling forced mass transfer of wastewater within the membrane channels. This effectively solves the problems of limited effective electroactive area and low mass transfer efficiency of traditional flat plate electrodes, thus improving... To improve the degradation efficiency of organic pollutants and reduce energy consumption, when using this Ti4O7-based nanotube electrochemical anode membrane for organic wastewater treatment, by adopting a cross-flow filtration operation mode and optimizing the applied voltage and current density operating parameters, the strong oxidizing free radicals generated on the nanotube structure surface can decompose intermediate products in a timely manner while efficiently degrading organic pollutants. In addition, the fluid flushing effect can effectively reduce the adsorption and accumulation of pollutants on the active sites, thereby solving the problem of passivation of active sites caused by the adsorption of intermediate products in traditional electrodes. This gives the anode membrane excellent anti-fouling performance and long-term operational stability, while maintaining high current efficiency.

[0034] By comparing and analyzing the relevant data in the table, it can be seen that the Ti4O7-based nanotube electrochemical anode membrane prepared by the present invention has high electrocatalytic activity, high pollutant degradation efficiency and ultra-long service life. This indicates that the preparation and application method of the Ti4O7-based nanotube electrochemical anode membrane provided by the present invention has a broader market prospect and is more suitable for promotion.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a Ti4O7-based nanotube electrochemical anolyte film, characterized in that, Includes the following steps: Step 1: Pre-treatment of porous titanium tubes. Select porous titanium tubes as the substrate and perform surface grinding, cleaning and chemical etching to remove surface stains and activate the surface of the titanium tubes. Step 2: Electrochemical oxidation treatment. The pretreated porous titanium tube is used as the anode, and cathode electrodes are set on its inner and outer sides respectively. It is placed in a specific electrolyte and electrochemical oxidation reaction is carried out under constant voltage conditions to form the initial nanotube structure. Step 3: Cleaning treatment. The porous titanium tube after electrochemical oxidation is immersed in an organic solvent to remove residual electrolytes and impurities from the surface. Step 4: Calcination treatment. The cleaned porous titanium tubes are placed in a high-temperature furnace and calcined at a controllable heating rate to transform the surface nanotube structure into a titanium dioxide nanotube array. Step 5: Reduction treatment. The calcined titanium dioxide nanotube array is used as the cathode and placed together with the auxiliary anode in a reducing electrolyte. Through electrochemical reduction reaction, titanium dioxide is converted into titanium suboxide, and finally Ti4O7-based nanotube electrochemical anode film is obtained. The porous titanium tube has a pore size of 1-6 μm, a porosity of 60%-80%, and a specific surface area of ​​4-6 m² / g; The electrolyte comprises ethylene glycol, ultrapure water, and sodium fluoride, wherein the volume fraction of ethylene glycol is 95%, the volume fraction of ultrapure water is 5%, and the mass fraction of sodium fluoride is 0.5%. The constant voltage condition is 20-50V, and the reaction time is 3-6h; The calcination temperature is 400-600℃, the calcination time is 2-4h, and the heating and cooling rates are both 3-5℃ / min; The reducing electrolyte contains ammonium sulfate and chloroplatinic acid, wherein the concentration of ammonium sulfate is 1 mol / L and the concentration of chloroplatinic acid is 0.5 mmol / L; The current density of the reduction treatment is 2-6 mA / cm², and the reaction time is 10-30 min.

2. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, The preprocessing in step one includes the following sub-steps: First, sand both sides of the porous titanium tube with sandpaper until the surface is smooth, shiny, and has a metallic luster. Secondly, rinse both sides of the polished titanium tube three times with deionized water, and then soak it in a 5% sodium hydroxide solution at 90°C for 2 hours to thoroughly remove surface stains. Finally, the titanium tube treated with alkali was rinsed with deionized water and then immersed in a 4% (w / w) boiling oxalic acid solution for etching for 2.5 hours. After etching, it was rinsed repeatedly with deionized water to remove any adhering titanium oxalate residue. The porous titanium tube has the following dimensions: inner diameter 2.4cm, outer diameter 3cm, wall thickness 1cm, and length 35cm. The sanding process uses 400-600 grit sandpaper with a sanding pressure of 0.1-0.3 MPa.

3. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 2, characterized in that, In the pretreatment of step one, the mass fraction of sodium hydroxide solution is 5%±0.5%, the mass fraction of oxalic acid solution is 4%±0.5%, and the temperature of oxalic acid solution is maintained at boiling. Each rinse with deionized water takes 1-2 minutes, and the total rinsing time is not less than 5 minutes. The porous titanium tube is made of industrial pure titanium with a titanium content of not less than 99.5%. The porosity is determined by mercury intrusion porosimetry to ensure uniform pore size distribution.

4. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, In the electrochemical oxidation process of step two, the cathode electrode includes a thin stainless steel tube and a thick stainless steel tube. The stainless steel tube has a diameter of 4mm and a length of 35cm and is placed inside the center of the porous titanium tube. The stainless steel tube has an inner diameter of 5cm, an outer diameter of 5.2cm, a wall thickness of 2mm, and a length of 35cm, and is placed on the outside of the porous titanium tube. The distance between the porous titanium tube and the cathode electrode is 20mm±2mm, and it is connected to a DC power supply through a wire. The positive terminal is connected to the porous titanium tube, and the negative terminal is connected to the stainless steel electrode. The pH of the electrolyte is adjusted to 3-5, using hydrochloric acid or sodium hydroxide for fine-tuning to ensure the stability of the electrochemical reaction.

5. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, The electrolyte contains 0.5% ± 0.1% sodium fluoride by mass, and the electrolyte must be filtered through a 0.22 μm microporous membrane before use to remove suspended particles. The specific parameters of the constant voltage condition are: initial voltage 20V, gradually increased to 50V, and the voltage increase rate is 5V / min; The electrochemical oxidation reaction is carried out at room temperature, and the electrolyte is stirred with a magnetic stirrer at a speed of 100-200 r / min during the reaction to ensure uniform mass transfer.

6. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, In the cleaning process of step three, the organic solvent is anhydrous ethanol, the soaking time is 10-40 min, and ultrasonic assisted cleaning is performed for 1 min every 5 min during the soaking process. After cleaning, the porous titanium tube needs to be dried in an oven at 50-60℃ for 30 minutes until there is no residual solvent on the surface; The purity of the anhydrous ethanol is not less than 99.7%, and the amount used for each cleaning is 3-5 times the volume of the titanium tube.

7. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, The calcination process in step four is carried out in a muffle furnace under an air atmosphere with an oxygen volume fraction of 21% ± 5%. During the calcination process, the morphology of the nanotube array is monitored by scanning electron microscopy to ensure that the tubular structure is continuous and uniformly distributed. The titanium dioxide nanotube array has a diameter of 50-100 nm, a length of 1-2 μm, and the array orientation is perpendicular to the surface of the titanium tube.

8. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, In the reduction process of step five, the auxiliary anode is a Ti / Ti4O7 electrode prepared by plasma spraying, the size of which matches the porous titanium tube. The pH of the reducing electrolyte is maintained at 2-3 and adjusted using sulfuric acid; The electrochemical reduction reaction is carried out at room temperature, and the electrode must be rinsed three times with deionized water after the reaction and stored under a nitrogen atmosphere to prevent oxidation.

9. The method for preparing a Ti4O7-based nanotube electrochemical anolyte according to claim 1, characterized in that, The resulting Ti4O7-based nanotube electrochemical anolyte film exhibits a dense, porous tubular structure. X-ray diffraction analysis revealed that the main phase is Ti4O7, and the oxygen vacancy concentration, as determined by XPS, is 10-15 at%. The oxygen evolution potential of the anolyte is 2.5-3.1V, and the electrochemical active area is calculated to be 5-10 times that of a conventional planar electrode by cyclic voltammetry. The mechanical strength of the anode membrane is tested by a three-point bending test, with a bending strength of not less than 200 MPa and an estimated service life of more than 1000 hours.

10. A method for applying a Ti4O7-based nanotube electrochemical anode membrane, wherein the Ti4O7-based nanotube electrochemical anode membrane obtained by any one of the preparation methods described in claims 1-9 is applied to the electrochemical treatment of organic wastewater, characterized in that, Specifically, the following steps are included: Application Step 1: Construct an electrochemical reactor, using a Ti4O7-based nanotube electrochemical anolyte as the anode, with a stainless steel cathode placed in the center, and the outer wall of the reactor being made of plexiglass, forming a tubular membrane reactor; Application Step 2: Pump the organic wastewater into the reactor, control the wastewater flow rate at 0.5-2 L / min, and adjust the influent pH value to 3-11 to adapt to different water qualities; Application Step 3: Apply DC power, connect the anode and cathode to the positive and negative terminals respectively, set the voltage to 3-5V, the current density to 5-15mA / cm², and the reaction time to 20-60min; Application Step 4: Wastewater is circulated in the reactor using a cross-flow filtration method, and the permeate flows out from the side wall of the reactor. Samples of the effluent after electrochemical degradation are taken for analysis. The organic wastewater includes carbamate pesticide wastewater, in which the initial concentrations of typical pollutants, carbofuran and carbaryl, are 10-100 mg / L. The application method achieves a removal rate of 90%-96% for organic pollutants and a total organic carbon removal rate of 70%-80%, while consuming 30%-50% less energy than traditional electrochemical methods. The reactor operates at room temperature and requires no chemical reagents, thus achieving green processing.

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