High-activity electrode, preparation method thereof and application of high-activity electrode in sewage treatment

Abstract

The application relates to a high-activity electrode and a preparation method thereof and application of the electrode in sewage treatment. The preparation method is as follows: Sn source, Sb source and Tb source are configured into a mixed solution, the Tb-Sn-Sb sol is obtained after ultrasonic treatment and standing and aging, the Tb-Sn-Sb sol is uniformly coated on the surface of an electrode substrate, and the high-activity titanium-based tin dioxide-antimony electrode is prepared through heat treatment at a specific temperature. The application finds that, for the first time, the rare earth element Tb is doped in the Ti / SnO2-Sb electrode, the conductivity of the Ti / SnO2-Sb electrode can be greatly improved, and the treatment capacity of the Ti / SnO2-Sb electrode for wastewater containing organic pollutants can be greatly improved. The removal rate of the Ti / SnO2-Sb-Tb electrode for moxifloxacin reaches more than 84%, while the removal rate of the conventional Ti / SnO2-Sb electrode for moxifloxacin is only 58.4%, and the removal rate of the Ti / SnO2-Sb-Ho electrode doped with other rare earth elements for moxifloxacin is 74.1%, which further shows that the doping of the rare earth element Tb in the Ti / SnO2-Sb electrode can greatly improve the treatment capacity of the electrode for wastewater containing organic pollutants.

Description

Technical Field

[0001] This invention relates to a highly active electrode, its preparation method, and its application in wastewater treatment. Specifically, it relates to a titanium-based tin dioxide-antimony electrode with higher electrode activity, stronger electrocatalytic performance, and longer lifespan, its preparation method, and its application in treating antibiotic-containing wastewater, belonging to the field of electrochemical water treatment technology. Background Technology

[0002] Antibiotics are broad-spectrum drugs used to treat diseases in humans and animals, effectively inhibiting the growth of microorganisms. Currently, antibiotic residues are continuously detected in water bodies, drawing global attention and causing a series of environmental problems. Furthermore, antibiotic residues in the environment can have negative effects on organisms, such as disrupting endocrine function and exhibiting genotoxicity. Pharmaceutical wastewater requires treatment before discharge, and approximately 70% of these antibiotics are excreted into the environment in a stable state from humans and animals, resulting in high concentrations of antibiotic residues in wastewater, soil, and sediments.

[0003] Current treatment technologies and methods for antibiotic wastewater mainly include adsorption, photodegradation, electrolysis, membrane separation, and reduction. Exploring efficient and economical antibiotic wastewater treatment technologies has significant practical and theoretical implications. Currently, electrochemical oxidation technology is widely used for recalcitrant wastewater due to its ease of operation, lack of secondary pollution, and status as an environmentally friendly method. Therefore, electrochemical treatment technology shows great promise in wastewater treatment. In electrochemical reactions, the role of the electrode is dominant; therefore, finding high-performance electrode materials and exploring their impact on electrocatalytic efficiency is particularly important in electrocatalytic reactions.

[0004] Electrochemical oxidation technology, characterized by high removal efficiency, simple operation, low cost, and no secondary pollution, has gradually become one of the most promising technologies in the water treatment field. The electrode is a core component in electrocatalytic oxidation technology, influencing conductivity, electron transfer rate, and the ease of generating activated reactants. The choice of electrode material directly affects the electrocatalytic performance. Although noble metal electrocatalysts such as Pt and RuO2 exhibit outstanding performance in electrocatalysis, their application is greatly limited due to their high cost and scarcity. For DSA electrodes formed by coating conventional electrode substrates, Ti-SnO2 electrodes are widely used anode materials in wastewater treatment. Rare earth element doping of Ti / SnO2-Sb electrodes can effectively alter the surface morphology and lattice parameters of metal oxide electrodes, thereby improving the oxygen evolution potential, electrocatalytic activity, and lifespan of the electrode to a certain extent.

[0005] The conventional titanium-based tin dioxide-antimony electrodes currently in use have some drawbacks, such as brittle coating that is prone to peeling and insufficient stability during electrolysis. Therefore, it is necessary to modify the Ti / SnO2-Sb electrode by doping to further improve its catalytic activity and stability.

[0006] Rare earth elements (REs) possess unique potential for improving electrode catalytic performance through their distinctive unpaired 4f electrons. Lanthanide rare earth compounds, with their abundant energy level structures and unique ff electron transitions, exhibit advantages such as long luminescence lifetime, high luminescence efficiency, and large Stokes shift, making them widely used in luminescence, electrocatalysis, and magnetic fields. They also show great promise for development in the field of electrochemistry. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a highly active electrode, its preparation method, and its application in wastewater treatment. The highly active electrode provided by this invention solves the problems of low pollutant degradation efficiency and short electrode lifespan of ordinary Ti / SnO2-Sb electrodes. Furthermore, it can shorten pollutant degradation time, significantly reduce experimental energy consumption, and allow the electrode to be reused three times or more without reducing the degradation rate. Simultaneously, the surface coating of the prepared highly active electrode is more dense and uniform, greatly improving the electrode's electrocatalytic performance and conductivity. Invention Overview:

[0009] This invention prepares a mixed solution of Sn, Sb, and Tb sources, which, after ultrasonic treatment and static aging, yields a Tb-Sn-Sb sol. This Tb-Sn-Sb sol is then uniformly coated onto an electrode substrate surface, followed by heat treatment at a specific temperature to obtain a highly active titanium-based tin dioxide-antimony electrode. The resulting titanium-based tin dioxide-antimony electrode has a denser and more uniform coating surface, smaller grain size, improved conductivity, better performance, and longer lifespan. This electrode will be used for the treatment of wastewater containing fluoride antibiotics (moxifloxacin). Detailed description of the invention:

[0011] A method for preparing a highly active titanium-based tin dioxide-antimony electrode includes the following steps:

[0012] (1) Add Sn source, Sb source and Tb source to organic solvent to prepare a mixed solution. The molar concentration ratio of Sn source, Sb source and Tb source in the mixed solution is Sn:Sb:Tb=100:10:(0.1~2); then sonicate the mixed solution at 50~150Hz for 10~20min and let it stand for 1~2h to obtain Tb-Sn-Sb sol;

[0013] (2) The pretreated electrode substrate is completely immersed in the Tb-Sn-Sb sol obtained in step (1). After taking it out, the Tb-Sn-Sb sol on the surface of the electrode substrate is evenly coated with a soft brush. Then the coated electrode substrate is dried at 100-130℃ for 10-20 min, and then heat-treated at 450-600℃ for 10-30 min. After taking it out, it is cooled to room temperature, the surface is cleaned with deionized water, and then dried.

[0014] (3) Repeat step (2) for complete immersion and coating 5 to 9 times. After the last complete immersion and coating, dry the electrode substrate at 100 to 130°C for 10 to 20 minutes, and then calcine at 550 to 700°C for 1 to 2 hours. After taking it out, cool it to room temperature, clean the surface with deionized water and dry it to obtain a highly active titanium-based tin dioxide-antimony electrode.

[0015] According to a preferred embodiment of the present invention, in step (1), the Sn source is crystalline tin tetrachloride, the Sb source is antimony trichloride, and the Tb source is terbium nitrate.

[0016] According to a preferred embodiment of the present invention, in step (1), the organic solvent is an ethylene glycol solution of citric acid, and the total molar ratio of Sn source to Sb source in the mixed solution is citric acid: ethylene glycol = 1:(2-5):(8-12).

[0017] More preferably, in step (1), the organic solvent is an ethylene glycol solution of citric acid, and the total molar number of Sn source and Sb source in the mixed solution is citric acid: ethylene glycol = 1:3:10.

[0018] According to a preferred embodiment of the present invention, in step (1), the molar concentration ratio of the Sn source, Sb source and Tb source is Sn:Sb:Tb = 100:10:1.5.

[0019] According to a preferred embodiment of the present invention, in step (2), the electrode substrate is a titanium mesh, and its pretreatment method is as follows: after being polished, alkali washed, and acid washed in sequence, it is ultrasonically cleaned at 100Hz for 10 minutes, then cleaned with deionized water, placed in an oven to dry, and the pretreated electrode substrate is stored in anhydrous ethanol.

[0020] According to a preferred embodiment of the present invention, in step (2), the coated electrode substrate is placed in an electric heating drying oven and dried at 130°C for 20 minutes, and then placed in a muffle furnace and heat-treated at 500°C for 20 minutes.

[0021] According to a preferred embodiment of the present invention, in step (3), the number of times the complete immersion and coating are repeated is 6. After the last coating is completed, the electrode substrate is placed in an electric heating drying oven and dried at 130°C for 20 minutes. Then it is placed in a muffle furnace and calcined at 600°C for 2 hours. After being taken out, it is cooled to room temperature.

[0022] This invention provides a highly active titanium-based tin dioxide-antimony electrode prepared by the above method.

[0023] This invention also provides the application of a highly active titanium-based tin dioxide-antimony electrode in the treatment of wastewater containing organic pollutants.

[0024] According to a preferred embodiment of the present invention, the organic pollutant is a fluoroquinolone antibiotic.

[0025] Beneficial effects:

[0026] 1. This invention is the first to discover that doping Ti / SnO2-Sb electrodes with rare earth element Tb can significantly improve the conductivity of Ti / SnO2-Sb electrodes and their ability to treat wastewater containing organic pollutants.

[0027] 2. The highly active titanium-based tin dioxide-antimony electrode of this invention exhibits extremely strong degradation capabilities for organic pollutants. Experiments using moxifloxacin (MOX) technical solution to simulate fluoride-containing antibiotic wastewater show that the Ti / SnO2-Sb-Tb electrode of this invention achieves a moxifloxacin (MOX) removal rate of over 84%, while the conventional Ti / SnO2-Sb electrode only achieves 58.4%, and the Ti / SnO2-Sb-Ho electrode, doped with other rare earth elements, achieves a removal rate of 74.1%. This clearly demonstrates that doping the Ti / SnO2-Sb electrode with rare earth element Tb can significantly improve its treatment capacity for wastewater containing organic pollutants. Furthermore, this highly active titanium-based tin dioxide-antimony electrode can also be applied to the treatment of other toxic and harmful recalcitrant organic pollutants in aquatic environments.

[0028] 3. This invention employs a Tb-Sn-Sb sol coating method on the electrode substrate surface, combined with a brushing method and heat treatment at a specific temperature, to prepare a highly active titanium-based tin dioxide-antimony electrode. This highly active titanium-based tin dioxide-antimony electrode has a denser and more uniform coating surface, higher surface crystallinity, and smaller grain size, increasing the electrode's specific surface area. This, in turn, increases the contact between the electrode and the target contaminant, improving the electrode's conductivity, enhancing its performance, and increasing its electrocatalytic activity.

[0029] 4. This invention provides a method for preparing a highly active titanium-based tin dioxide-antimony electrode. This method combines a coating method with heat treatment at a specific temperature, is simple to operate, and uses Tb as the dopant, resulting in low material costs. Furthermore, this method can degrade recalcitrant organic compounds at room temperature and pressure, with mild reaction conditions, a simple reaction apparatus, and significantly shortened reaction time, greatly reducing energy consumption and facilitating large-scale production. Attached Figure Description

[0030] Figure 1 These are electron microscope (EM) images of the highly active titanium-based tin dioxide-antimony electrode of Example 1 and the electrode of Comparative Example 1, magnified at 1000x and 200x.

[0031] In the figure, a and c are Ti / SnO2-Sb electrodes of Comparative Example 1; b and d are highly active rare earth Tb modified titanium-based tin dioxide-antimony electrodes of Example 1.

[0032] Figure 2 The images show a comparison of the X-ray diffraction (XRD) spectra of the highly active titanium-based tin dioxide-antimony electrode of Example 1 and the electrode of Comparative Example 1.

[0033] Figure 3 The graph shows the removal rate curves of moxifloxacin (MOX) solution in simulated fluoride-containing antibiotic wastewater during the electrochemical degradation process of the highly active titanium-based tin dioxide-antimony electrode of Example 1, the Ti / SnO2-Sb electrode of Comparative Example 1, and the Ti / SnO2-Sb-Ho electrode of Comparative Example 2. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings, so that its objectives, advantages and technical solutions will be clearer, but should not be construed as limiting the present invention.

[0035] Example 1

[0036] A method for preparing a highly active Ti / SnO2-Sb-Tb electrode includes the following steps:

[0037] (1) Pretreatment of electrode substrate

[0038] ① Selection of electrode substrate: The anode material is selected as a 30mm×40mm×1mm titanium mesh, and the cathode material is selected as a 30mm×40mm×1mm titanium plate;

[0039] ② Grinding the electrode substrate: First, use 180-grit sandpaper to grind the surface of the titanium mesh and titanium plate over a large area. Then, use 300-grit sandpaper to continue grinding the titanium mesh and titanium plate to remove the oxides on the surface until the surface of the titanium substrate has a silvery-white metallic luster. Finally, place the ground titanium mesh and titanium plate in deionized water and clean it in 100Hz ultrasonic water for 10 minutes to clean the oxides that fell into the gaps of the titanium mesh and the edges of the titanium plate. Dry the surface of the cleaned electrode with an oven or hair dryer and set it aside.

[0040] ③ Pretreatment:

[0041] a. Alkali washing: Place the polished and cleaned titanium mesh and titanium plate in a 5% sodium carbonate solution. After heating to boiling, wash the titanium mesh and titanium plate with alkali for 1 hour to remove the oil stains on the electrode surface. After the alkali washing cools down, clean the electrode surface with deionized water.

[0042] b. Pickling: Next, place the alkaline-washed titanium mesh and titanium plate in a 10% oxalic acid solution. After boiling, pickle for 2-3 hours to remove residual oxides on the surface of the titanium mesh and titanium plate. During the pickling and etching process of the titanium mesh and titanium plate, the oxalic acid solution can be observed to gradually change from transparent to yellow and finally to black. This is because the oxalic acid solution reacts with the oxides on the surface of the titanium mesh and titanium plate during the heating process. After pickling, the titanium mesh and titanium plate turn yellowish-brown. After pickling, ultrasonically clean the titanium plate and titanium mesh to remove the residual oxalic acid solution on the surface.

[0043] c. Secondary alkaline and acid washing: The cleaned titanium mesh and titanium plate are subjected to secondary alkaline and acid washing. After acid washing, the titanium mesh and titanium plate are placed in a 5% sodium carbonate solution for secondary alkaline washing to remove the residual oxalic acid solution on the electrode substrate surface. After cleaning the electrode substrate surface with deionized water, it is placed in an oxalic acid solution to clean the residual sodium carbonate solution on the surface again. The electrode substrate surface after the secondary acid and alkaline washing has a rough surface. The surface of the titanium mesh and titanium plate after the secondary alkaline and acid washing is cleaned with deionized water and ultrasonicated for 10 minutes to remove the residual impurities on the surface. Finally, the treated and cleaned titanium mesh and titanium plate are placed in an 80℃ oven to dry the surface moisture, and the dried electrode substrate is stored in anhydrous ethanol for later use.

[0044] (2) Preparation of Tb-Sn-Sb sol

[0045] Ethylene glycol was heated to 65°C in a water bath, and citric acid was added and stirred until completely dissolved to obtain an ethylene glycol solution of citric acid. Then, the temperature was raised to 90°C, and tin tetrachloride (SnCl4), antimony trichloride (SbCl3), and terbium nitrate (Tb·3NO3·6H2O) were added to the organic solvent according to a molar ratio of Sn:Sb:Tb = 100:10:1.5. The solution was heated and stirred in a 90°C water bath until dissolved to obtain a yellow-green mixed solution. After cooling, the mixed solution was sonicated at 100Hz for 15 min and allowed to stand for 1.5 h to obtain a Tb-Sn-Sb sol.

[0046] The total molar ratio of Sn source to Sb source in the mixed solution is citric acid: ethylene glycol = 1:3:10.

[0047] (3) Preparation of highly active Ti / SnO2-Sb-Tb electrodes

[0048] After rinsing the pretreated titanium mesh with deionized water, it was dried in an oven at 100°C for 15 minutes to obtain the dried titanium mesh substrate. Then, the titanium mesh substrate was completely immersed in Tb-Sn-Sb sol. After taking it out, the Tb-Sn-Sb sol was brushed onto the surface of the titanium mesh substrate with a soft brush to ensure that the coating solution evenly covers the surface of the titanium mesh substrate. The coated titanium mesh substrate was then placed in a 130°C electric heating drying oven to dry for 20 minutes, and then placed in a muffle furnace at 500°C for heat treatment for 20 minutes. After taking it out, it was cooled to room temperature, the surface was cleaned with deionized water, and then dried.

[0049] Next, the titanium mesh substrate was completely immersed and coated again, and this process was repeated 6 times (a total of 7 complete immersions and coatings were performed). After the last coating, the titanium mesh substrate was placed in an electric heating drying oven and dried at 130°C for 20 minutes. Then, it was placed in a muffle furnace and calcined at 600°C for 2 hours. After being removed and cooled to room temperature, the surface was cleaned with deionized water and placed in an oven at 80°C for 15 minutes until completely dry, thus obtaining a highly active Ti / SnO2-Sb-Tb electrode.

[0050] Example 2

[0051] A method for preparing a highly active Ti / SnO2-Sb-Tb electrode, the specific steps are the same as in Example 1, except that in step (2), the molar concentration ratio of tin tetrachloride (SnCl4), antimony trichloride (SbCl3) and terbium nitrate (Tb·3NO3·6H2O) is Sn:Sb:Tb=100:10:2.

[0052] Example 3

[0053] A method for preparing a highly active Ti / SnO2-Sb-Tb electrode, the specific steps are the same as in Example 1, except that in step (2) and step (3), the electrode coating is coated a total of 10 times.

[0054] Example 4

[0055] A method for preparing a highly active Ti / SnO2-Sb-Tb electrode, the specific steps are the same as in Example 1, except that in step (2) and step (3), the titanium mesh substrate after the last complete immersion and coating is placed in a box-type resistance furnace and calcined at 700°C for 2 hours.

[0056] Comparative Example 1

[0057] A method for preparing a Ti / SnO2-Sb electrode, comprising the following steps:

[0058] (1) The pretreatment of the electrode substrate was carried out according to the method of Example 1;

[0059] (2) Ethylene glycol was heated to 65°C in a water bath, and citric acid was added and stirred until completely dissolved to obtain an ethylene glycol solution of citric acid. Then the temperature was raised to 90°C, and tin tetrachloride (SnCl4) and antimony trichloride (SbCl3) were added to the organic solvent according to a molar ratio of Sn:Sb = 10:1. The solution was heated and stirred in a 90°C water bath until dissolved to obtain a mixed solution. After cooling, the mixed solution was sonicated at 100Hz for 15 minutes to obtain Sn-Sb sol. The total molar ratio of Sn source to Sb source in the mixed solution was citric acid: ethylene glycol = 1:3:10.

[0060] (3) The electrode was prepared by completely immersing and coating according to the method in step (3) of Example 1 to obtain Ti / SnO2-Sb electrode.

[0061] Comparative Example 2

[0062] A method for preparing a Ti / SnO2-Sb-Ho electrode, comprising the following steps:

[0063] (1) The pretreatment of the electrode substrate was carried out according to the method of Example 1;

[0064] (2) Ethylene glycol was heated to 65°C in a water bath, and citric acid was added and stirred until completely dissolved to obtain an ethylene glycol solution of citric acid. Then, the temperature was raised to 90°C, and tin tetrachloride (SnCl4), antimony trichloride (SbCl3), and holmium nitrate (Ho·3NO3·5H2O) were added to the organic solvent according to the molar ratio of Sn:Sb:Ho = 100:10:1.5. The solution was heated and stirred in a 90°C water bath until dissolved to obtain a mixed solution. After cooling, the mixed solution was sonicated at 100Hz for 15 minutes to obtain Sn-Sb-Ho sol. The total molar ratio of Sn source to Sb source in the mixed solution was citric acid:ethylene glycol = 1:3:10.

[0065] (3) The electrode was prepared by completely immersing and coating according to the method in step (3) of Example 1 to obtain the Ti / SnO2-Sb-Ho electrode.

[0066] Test case

[0067] 1. The highly active Ti / SnO2-Sb-Tb electrode prepared in Example 1 and the Ti / SnO2-Sb electrode prepared in Comparative Example 1 were subjected to surface electron microscopy (SEM). The images at 1000x and 200x magnification are shown below. Figure 1 As shown.

[0068] pass Figure 1 a and Figure 1The comparison in b reveals a significant difference in morphology between the highly active Ti / SnO2-Sb-Tb electrode prepared in Example 1 and the Ti / SnO2-Sb electrode prepared in Comparative Example 1. The surface of the traditional Ti / SnO2-Sb electrode is uneven, with large crystal particles in most areas exhibiting clustering. In contrast, the highly active Ti / SnO2-Sb-Tb electrode of Example 1 forms a dense coating that is uniformly distributed and well-dispersed on the electrode surface, without any clustering.

[0069] pass Figure 1 c and Figure 1 The comparison of d shows that no obvious active sites are generated on the surface of the conventional Ti / SnO2-Sb electrode in Comparative Example 1, while the highly active Ti / SnO2-Sb-Tb electrode in Example 1 has uniform active grain sites generated on its surface.

[0070] Therefore, by doping the Ti / SnO2-Sb electrode with rare earth element Tb, the Ti / SnO2-Sb electrode coating prepared by Tb-Sn-Sb sol coating has a denser and more uniform surface, higher surface crystallinity, and smaller grain size, which increases the specific surface area of ​​the electrode. This increases the contact between the electrode and the target pollutant, improves the conductivity of the electrode, enhances the performance of the electrode, improves the electrocatalytic activity of the electrode, and extends the service life of the electrode.

[0071] 2. X-ray diffraction (XRD) analysis was performed on the highly active Ti / SnO2-Sb-Tb electrode prepared in Example 1 and the Ti / SnO2-Sb electrode prepared in Comparative Example 1. The obtained spectra are shown below. Figure 2 As shown.

[0072] Depend on Figure 2 It is known that the highly active Ti / SnO2-Sb-Tb electrode doped with rare earth element Tb exhibits weaker diffraction peak intensities compared to the undoped electrode, indicating lattice expansion. This is due to the larger ionic radius of Tb. 3+ Substitute Sn into the SnO2 lattice 4+ Meanwhile, the diffraction peaks of the rare-earth Tb-doped modified electrode are slightly wider. Since the average grain size is inversely proportional to the diffraction peak width, it can be seen that the SnO2 grain size in the coating is smaller than that in the blank electrode. This indicates that the rare-earth Tb doping refines the SnO2 grains in the coating, increases the specific surface area for electrocatalytic reactions, and improves the electrocatalytic performance of the rare-earth-doped modified electrode. The conclusions obtained from the XRD pattern are consistent with the observations from the SEM images and the actual degradation results.

[0073] 3. The highly active Ti / SnO2-Sb-Tb electrode prepared in Example 1, the Ti / SnO2-Sb electrode prepared in Comparative Example 1, and the Ti / SnO2-Sb-Ho electrode prepared in Comparative Example 2 were subjected to electrochemical electrocatalytic degradation tests of moxifloxacin (MOX) solution.

[0074] The test conditions were as follows: the anodes were the highly active Ti / SnO2-Sb-Tb electrode of Example 1, the Ti / SnO2-Sb electrode of Comparative Example 1, and the Ti / SnO2-Sb-Ho electrode of Comparative Example 2, respectively; the cathode was a pure titanium plate; the electrolyte was a Na2SO4 solution containing 0.05 mol / L; the concentration of the target pollutant moxifloxacin was 100 mg / L; the pH value was 6.5 under the initial conditions; and the current density was 20 mA / cm². 2 The effective electrolysis area is 30mm x 40mm, the electrolysis time is 30min, and the test results are as follows: Figure 3 As shown.

[0075] Depend on Figure 3 It can be seen that the high-activity Ti / SnO2-Sb-Tb electrode of Example 1 of the present invention achieved a removal rate of over 84% for moxifloxacin (MOX), while the conventional Ti / SnO2-Sb electrode of Comparative Example 1 only achieved a removal rate of 58.4% for moxifloxacin (MOX), and the Ti / SnO2-Sb-Ho electrode of Comparative Example 2 with Ho doping achieved a removal rate of 74.1% for moxifloxacin (MOX). In other words, the Ti / SnO2-Sb-Tb electrode of Example 1 improved the removal rate of moxifloxacin (MOX) by 9.9% to 25.6% compared to Comparative Examples 1 and 2. This fully demonstrates that the high-activity Ti / SnO2-Sb-Tb electrode of Example 1 has a very strong degradation ability for organic pollutants, that is, doping the Ti / SnO2-Sb electrode with rare earth element Tb can significantly improve the electrocatalytic degradation effect, electrocatalytic activity, and treatment capacity for wastewater containing organic pollutants.

Claims

1. A method for preparing a highly active titanium-based tin dioxide-antimony electrode, characterized in that, The steps include the following: (1) Add crystalline tin tetrachloride, antimony trichloride and terbium nitrate to the ethylene glycol solution of citric acid to prepare a mixed solution. The molar ratio of Sn, Sb and Tb ions in the mixed solution is 100:10:1.5, and the total number of Sn and Sb moles: citric acid: ethylene glycol = 1:3:

10. The mixed solution was then sonicated at 50-150 Hz for 10-20 min and allowed to stand for 1-2 h to obtain Tb-Sn-Sb sol. (2) The pretreated electrode substrate is completely immersed in the Tb-Sn-Sb sol obtained in step (1). After taking it out, the Tb-Sn-Sb sol on the surface of the electrode substrate is evenly coated with a soft brush. Then the coated electrode substrate is dried at 100~130℃ for 10~20min, and then heat-treated at 450~600℃ for 10~30min. After taking it out, it is cooled to room temperature, the surface is cleaned with deionized water, and then dried. (3) Repeat step (2) for complete immersion and coating 5 to 9 times. After the last complete immersion and coating, dry the electrode substrate at 100 to 130°C for 10 to 20 minutes, and then calcine at 550 to 700°C for 1 to 2 hours. After taking it out, cool it to room temperature, clean the surface with deionized water and dry it to obtain a highly active titanium-based tin dioxide-antimony electrode.

2. The preparation method according to claim 1, characterized in that, In step (2), the electrode substrate is a titanium mesh, and its pretreatment method is as follows: after grinding, alkali washing, acid washing, ultrasonic cleaning at 100Hz for 10 minutes, then cleaning with deionized water, drying in an oven, and storing the pretreated electrode substrate in anhydrous ethanol.

3. The preparation method according to claim 1, characterized in that, In step (2), the coated electrode substrate is placed in an electric heating drying oven and dried at 130°C for 20 minutes, and then placed in a muffle furnace and heat-treated at 500°C for 20 minutes.

4. The preparation method according to claim 1, characterized in that, In step (3), the repeated immersion and coating are performed 6 times. After the last coating is completed, the electrode substrate is placed in an electric heating drying oven and dried at 130°C for 20 minutes. Then it is placed in a muffle furnace and baked at 600°C for 2 hours. After being taken out, it is cooled to room temperature.

5. A highly active titanium-based tin dioxide-antimony electrode, characterized in that, It is prepared according to the preparation method according to any one of claims 1 to 4.

6. The application of the highly active titanium-based tin dioxide-antimony electrode according to claim 5 in the treatment of wastewater containing organic pollutants, characterized in that, The organic pollutant is a fluoroquinolone antibiotic.

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