Preparation method of a defective carbon nanotube electrocatalytic film

Abstract

The application provides a preparation method of a defect-rich carbon nanotube electrocatalytic membrane. The method first oxidizes carboxylated carbon nanotubes with an ammonium persulfate-hydrochloric acid solution, then reduces the oxidized carbon nanotubes through high-temperature annealing to obtain defect-rich carbon nanotubes, and finally loads the defect-rich carbon nanotubes onto the surface of a polymer-based membrane to obtain a defect-rich carbon nanotube electrocatalytic membrane. The process of regulating the defects of the carbon nanotubes does not require strong oxidizing acids such as nitric acid and concentrated sulfuric acid, and does not require the addition of a precursor of a foreign atom such as N. The operation is fast and simple, and the ammonium persulfate-hydrochloric acid solution can be reused, thereby reducing the consumption of reagents. Meanwhile, the defect degree of the carbon nanotubes of the electrocatalytic membrane is obviously improved, the antibiotics can be quickly degraded through strong hole oxidation, the bottleneck of the mutual restriction of flux and interception in the traditional membrane separation technology is broken through, and the electrocatalytic membrane has great application potential in the field of wastewater advanced treatment.

Description

Technical Field

[0001] This invention belongs to the field of water treatment materials, and in particular relates to a method for preparing a defect-rich carbon nanotube electrocatalytic membrane. Background Technology

[0002] Traditional polymer membrane water treatment technologies face the challenge of a trade-off between flux and removal rate. Generally, higher pollutant removal rates result in lower membrane flux, and pollutants cannot be chemically degraded. In recent years, carbon nanotube electrocatalytic membranes, obtained by loading carbon nanotubes onto the surface of polymer membranes, have attracted considerable attention. These membranes can utilize the catalytic activity of carbon nanotubes to achieve the chemical degradation of pollutants under an applied voltage, thus breaking the trade-off between flux and removal rate. Research has found that defects in carbon nanotubes play a crucial role in the pollutant degradation process. Under an electric field, defect sites in carbon nanotubes can generate holes, thereby oxidizing pollutants, particularly suitable for the degradation of electron-rich small molecule pollutants, such as antibiotics.

[0003] Existing methods for controlling defects in carbon nanotubes typically involve strong oxidation processes using nitric acid or concentrated sulfuric acid, and may even require adding nitrogen-containing precursors to dope nitrogen and other heteroatoms into the carbon nanotube lattice structure. These methods are subject to harsh reaction conditions and involve complex steps. There is an urgent need to develop a simple, easy-to-implement, rapid, and time-saving method for controlling carbon nanotube defects to improve the chemical degradation efficiency of pollutants by carbon nanotube electrocatalytic membranes. Summary of the Invention

[0004] In view of this, the present invention aims to provide a method for preparing defect-rich carbon nanotube electrocatalytic membranes to solve the above problems.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows: A method for preparing a defect-rich carbon nanotube electrocatalytic membrane, comprising the following steps: S1. Oxidation of carbon nanotubes by ammonium persulfate: Carboxylated carbon nanotubes were immersed in an ammonium persulfate-hydrochloric acid solution and ultrasonically treated. The product was centrifuged, washed several times with deionized water, and dried to obtain oxidized carbon nanotubes. The concentration of ammonium persulfate in the ammonium persulfate-hydrochloric acid solution was 0.1~0.5 mol / L, the concentration of hydrochloric acid was 1~4 mol / L, and the concentration of carboxylated carbon nanotubes in the ammonium persulfate-hydrochloric acid solution was 5~10 g / L. S2. Annealing and Reduction of Carbon Oxide Nanotubes: The carbon oxide nanotubes obtained in S1 were transferred to a tube furnace and annealed at 1000-1200℃ for 1 hour in a nitrogen atmosphere. Afterwards, they were washed with deionized water and dried to obtain defect-rich carbon nanotubes. The defect level of the carbon nanotubes... I D / I G=1.3~1.5; S3. Load defect-rich carbon nanotubes onto a polymer base film to obtain a defect-rich carbon nanotube electrocatalytic membrane.

[0006] Furthermore, in S1, the carboxyl group content of the carboxylated carbon nanotubes is 2%~3%, and the length of the carbon nanotubes is 10~30µm. The introduction of carboxyl groups partially disrupts the carbon lattice structure of the carbon nanotubes, which is beneficial to the subsequent oxidation process of ammonium persulfate.

[0007] Furthermore, in S1, the ultrasound conditions are: 500~800W, 30~40min; The drying conditions are: 60~70℃, 10~12h.

[0008] Furthermore, in S2, the heating and cooling rates are 5℃ / min.

[0009] Annealing time needs to be controlled; excessively long annealing times will damage the lattice structure of carbon nanotubes, which is detrimental to electrocatalysis.

[0010] Furthermore, in S2, the drying conditions are: 60~70℃, 10~12h.

[0011] Furthermore, the method for loading defect-rich carbon nanotubes onto a polymer base film is vacuum filtration, or after vacuum filtration, crosslinking agents are used to crosslink the carbon nanotube layer, with the carbon nanotubes loaded on the upper or lower surface of the polymer base film.

[0012] Furthermore, the polymer base membrane has a pore size of 0.02~0.22µm and is made of polyethersulfone or polyvinylidene fluoride.

[0013] Compared with existing technologies, the method for preparing defect-rich carbon nanotube electrocatalytic membranes described in this invention has the following advantages: (1) The present invention does not require the use of strong oxidizing acids such as nitric acid and concentrated sulfuric acid for the control of defects in carbon nanotubes, and the reaction conditions are relatively mild and safe.

[0014] (2) The present invention does not require an external N source for the control of carbon nanotube defects, and the ammonium persulfate-hydrochloric acid solution can be reused, which reduces the cost of raw materials.

[0015] (3) The defect-rich carbon nanotube electrocatalytic membrane prepared by the present invention can be used to degrade low concentrations of antibiotics below 1 mg / L in water. The defect-rich carbon nanotube electrocatalytic membrane is used as a filter anode. A DC voltage of 0.5-2V is applied, and the antibiotics are degraded as the sewage flows through the pores of the defect-rich carbon nanotube electrocatalytic membrane.

[0016] (4) Compared with traditional polymer membranes, this invention improves the chemical degradation effect of pollutants, especially antibiotics, by increasing the defect level of carbon nanotubes and loading them onto the surface of polymer membranes, and achieves a higher antibiotic removal rate at a higher membrane flux. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 (a) shows the Raman spectrum of carbon nanotubes; (b) shows Example 1. I D / I G =1.47; (b) is Example 2, I D / I G =1.36; (c) is Comparative Example 1, I D / I G =1.00; (d) is Comparative Example 2, I D / I G =0.93; (e) is Comparative Example 3, I D / I G =1.06; Figure 2 The degradation effect of the defect-rich carbon nanotube electrocatalytic membrane prepared in Example 1 on three sulfonamide antibiotics: SDZ (sulfadiazine), SMZ (sulfadimethylpyrimidine), and SMX (sulfamethoxazole). Figure 3 The degradation effect of the defect-rich carbon nanotube electrocatalytic membrane prepared in Example 2 on three sulfonamide antibiotics: SDZ (sulfadiazine), SMZ (sulfadimethylpyrimidine), and SMX (sulfamethoxazole). Figure 4 The degradation effect of the defect-rich carbon nanotube electrocatalytic membrane prepared in Comparative Example 1 on three sulfonamide antibiotics is shown in Figure 1. SDZ is sulfadiazine, SMZ is sulfadimethylpyrimidine, and SMX is sulfamethoxazole. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0019] In this document, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0020] In this document, when values ​​are described as ranges, it should be understood that such disclosure includes disclosure of all possible subranges within that range, as well as the specific numerical values ​​falling within that range, regardless of whether the specific numerical value or specific subrange is explicitly specified.

[0021] In this article, the terms "multiple" or "more than" are used unless otherwise specified, referring to a quantity greater than or equal to 2. For example, "one or more" means one or more types.

[0022] In this document, the terms "preferred" and "more preferred" are used only to describe implementation methods or embodiments with better effects, and should be understood as not constituting a limitation on the scope of protection of this invention.

[0023] In this document, terms such as "further" are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of this invention.

[0024] In this article, the term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0025] In this document, the term "about" means a specified value of + / - 10%, preferably + / - 5%, and more preferably + / - 1%.

[0026] In this article, the terms “include,” “including,” “have,” “contain,” etc., are all open-ended terms, meaning that they include but are not limited to.

[0027] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0028] 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.

[0029] Example 1 The preparation method of defect-rich carbon nanotube electrocatalytic membrane includes the following steps: S1. Oxidation of carbon nanotubes by ammonium persulfate: Prepare an ammonium persulfate-hydrochloric acid solution with an ammonium persulfate concentration of 0.1 mol / L and a hydrochloric acid concentration of 1 mol / L. Add 8.3 g / L of carboxylated carbon nanotubes (carboxyl content of 2% and length of 10~30 µm) to the solution. Sonicate the solution in a water bath at 600 W for 30 min. After centrifugation, wash the product several times with deionized water and dry it in an oven at 60 °C for 12 h to obtain carbon oxide nanotubes.

[0030] S2, Annealing and Reduction of Carbon Oxide Nanotubes: The carbon oxide nanotubes obtained in S1 were transferred to a tube furnace and annealed at 1000℃ for 1 hour in a nitrogen atmosphere, with heating and cooling rates of 5℃ / min. After collection, the samples were washed repeatedly with deionized water and dried in a 60℃ oven for 12 hours to obtain defect-rich carbon nanotubes. The defect level was represented by the ratio of the D and G peak intensities in the Raman spectrum. I D / I G =1.47, as Figure 1 As shown in (a), the defect level is significantly improved compared to the original carbon nanotube (defect level). I D / I G =1.00, as Figure 1 (as shown in (c)).

[0031] S3. Preparation of defect-rich carbon nanotube electrocatalytic membranes: Defect-rich carbon nanotubes were loaded onto the lower surface of a polyethersulfone polymer base membrane (pore size 0.05µm) using a vacuum filtration method, and then the carbon nanotubes were chemically crosslinked with polyaniline and glutaraldehyde to obtain a defect-rich carbon nanotube electrocatalytic membrane.

[0032] Using the defect-rich carbon nanotube electrocatalytic membrane as the filter anode and a Ti plate as the cathode, a DC voltage of 1.5V was applied to filter a mixed solution (1 mg / L each) of three sulfonamide antibiotics: sulfadiazine (SDZ), sulfadimidine (SMZ), and sulfamethoxazole (SMX). The antibiotics were degraded as the wastewater flowed through the membrane pores, with removal rates of 91.21% (SDZ), 91.62% (SMZ), and 98.55% (SMX), respectively. Figure 2 As shown.

[0033] Example 2 The preparation method of defect-rich carbon nanotube electrocatalytic membrane includes the following steps: S1. Oxidation of carbon nanotubes by ammonium persulfate: Prepare an ammonium persulfate-hydrochloric acid solution with an ammonium persulfate concentration of 0.4 mol / L and a hydrochloric acid concentration of 1 mol / L. Add 8.3 g / L of carboxylated carbon nanotubes (carboxyl content of 2%, length of 10~30 µm) to the solution. Sonicate the solution in a water bath at 700 W for 30 min. After centrifugation, wash the product several times with deionized water and dry it in an oven at 70 °C for 10 h to obtain carbon oxide nanotubes.

[0034] S2, Annealing and Reduction of Carbon Oxide Nanotubes: The carbon oxide nanotubes obtained in S1 were transferred to a tube furnace and annealed at 1100 °C for 1 hour under a nitrogen atmosphere, with heating and cooling rates of 5 °C / min. After collection, the samples were washed repeatedly with deionized water and dried in a 60 °C oven for 10 hours to obtain defect-rich carbon nanotubes. The defect level was represented by the ratio of the D and G peak intensities in the Raman spectrum. I D / I G =1.36, as Figure 1 As shown in (b), the defect level is significantly improved compared to the original carbon nanotubes (defect level). I D / I G =1.00, as Figure 1 (as shown in (c)).

[0035] S3. Preparation of defect-rich carbon nanotube electrocatalytic membranes: Defect-rich carbon nanotubes were loaded onto the lower surface of a polyethersulfone polymer base membrane (pore size 0.05µm) using a vacuum filtration method, and then the carbon nanotubes were chemically crosslinked with polyaniline and glutaraldehyde to obtain a defect-rich carbon nanotube electrocatalytic membrane.

[0036] Using the defect-rich carbon nanotube electrocatalytic membrane as the anode and a Ti plate as the cathode, a DC voltage of 1.5V was applied to filter a mixed solution (1 mg / L) of three sulfonamide antibiotics: sulfadiazine (SDZ), sulfadimidine (SMZ), and sulfamethoxazole (SMX). The antibiotics were degraded as the wastewater flowed through the membrane pores, with removal rates of 81.14% (SDZ), 85.50% (SMZ), and 94.96% (SMX), respectively. Figure 3 As shown.

[0037] Comparative Example 1: Unoxidized and manufacturing-defective pristine carboxylated carbon nanotubes The difference from Example 1 is that steps S1 and S2 are omitted; that is, the carboxylated carbon nanotubes are neither oxidized nor annealed. Raman spectroscopy characterization of the original carbon nanotubes is performed to determine their defect level. I D / IG =1.00, as Figure 1 As shown in (c) in the figure.

[0038] The carbon nanotubes were directly loaded onto the lower surface of a polymer-based membrane to prepare an electrocatalytic membrane, using the same method as in Example 1.

[0039] Using the carbon nanotube electrocatalytic membrane as the anode and a Ti plate as the cathode, a DC voltage of 1.5V was applied to filter a mixed solution of three sulfonamide antibiotics (each 1 mg / L). The antibiotics were degraded as the wastewater flowed through the membrane pores, and the removal rates of the three antibiotics were 47.47% (SDZ), 44.08% (SMZ), and 52.28% (SMX), respectively. Figure 4 As shown.

[0040] Comparative Example 2: The effect of direct annealing reduction on defects The difference from Example 1 is that only step S2 is performed, where the carboxylated carbon nanotubes are directly annealed and reduced under the same conditions as in Example 1. The treated carbon nanotubes are characterized by Raman spectroscopy, and their defect levels are... I D / I G =0.93, as Figure 1 As shown in (d) in the figure.

[0041] It is evident that annealing and reducing carboxylated carbon nanotubes alone does not increase the defects of carbon nanotubes, and the effect is comparable to that of the untreated original carbon nanotubes in Comparative Example 1.

[0042] Comparative Example 3: Effect of carbon nanotube oxidation on defects only The difference from Example 1 is that only step S1 is performed; the oxidation method for carboxylated carbon nanotubes is the same as in Example 1. Raman spectroscopy characterization of the oxidized carbon nanotubes was conducted to determine their defect levels. I D / I G =1.06, as Figure 1 As shown in (e) in the diagram.

[0043] It is evident that oxidation of carboxylated carbon nanotubes alone does not significantly increase the defects in the carbon nanotubes, and the effect is comparable to that of untreated carbon nanotubes in Comparative Example 1.

[0044] Comparative Example 4: Ammonium persulfate concentration too low The difference from Example 1 is that the concentration of ammonium persulfate used in S1 is 0.05 mol / L, otherwise it is the same as Example 1.

[0045] Raman spectroscopy was used to characterize the treated carbon nanotubes, and their defect levels were determined. I D / I G =1.10.

[0046] Electrocatalytic membranes were prepared by loading the treated carbon nanotubes onto the lower surface of a polymer-based membrane, using the same method as in Example 1.

[0047] The carbon nanotube electrocatalytic membranes prepared achieved removal rates of 50.56% (SDZ), 48.37% (SMZ), and 55.89% (SMX) for the three antibiotics.

[0048] Comparative Example 5: Ammonium persulfate concentration was too high The difference from Example 1 is that the concentration of ammonium persulfate used in S1 is 0.6 mol / L, otherwise it is the same as Example 1.

[0049] Raman spectroscopy was used to characterize the treated carbon nanotubes, and their defect levels were determined. I D / I G =1.71.

[0050] Electrocatalytic membranes were prepared by loading the treated carbon nanotubes onto the lower surface of a polymer-based membrane, using the same method as in Example 1.

[0051] The carbon nanotube electrocatalytic membranes prepared achieved removal rates of 60.35% (SDZ), 62.27% (SMZ), and 65.75% (SMX) for the three antibiotics.

[0052] Comparative Example 6: The Necessity of Carboxylated Carbon Nanotubes The difference from Example 1 is that the carbon nanotubes used in S1 are carbon nanotubes without any functional groups, otherwise the same as in Example 1.

[0053] Raman spectroscopy was used to characterize the treated carbon nanotubes, and their defect levels were determined. I D / I G =1.2.

[0054] Electrocatalytic membranes were prepared by loading the treated carbon nanotubes onto the lower surface of a polymer-based membrane, using the same method as in Example 1.

[0055] The carbon nanotube electrocatalytic membranes prepared achieved removal rates of 55.65% (SDZ), 58.57% (SMZ), and 60.30% (SMX) for the three antibiotics.

[0056] Comparative Example 7: Excessive Carboxyl Functional Groups The difference from Example 1 is that the carboxyl content of the carboxylated carbon nanotubes used in S1 is 3.86%, while the rest is the same as in Example 1.

[0057] Raman spectroscopy was used to characterize the treated carbon nanotubes, and their defect levels were determined. I D / I G =1.6.

[0058] Electrocatalytic membranes were prepared by loading the treated carbon nanotubes onto the lower surface of a polymer-based membrane, using the same method as in Example 1.

[0059] The carbon nanotube electrocatalytic membranes prepared achieved removal rates of 70.25% (SDZ), 71.38% (SMZ), and 75.95% (SMX) for the three antibiotics.

[0060] Comparative Example 8: Replace with strong acid The difference from Example 1 is that the ammonium persulfate-hydrochloric acid solution in S1 is replaced with concentrated nitric acid, otherwise it is the same as Example 1.

[0061] Raman spectroscopy was used to characterize the treated carbon nanotubes, and their defect levels were determined. I D / I G =1.75.

[0062] Electrocatalytic membranes were prepared by loading the treated carbon nanotubes onto the lower surface of a polymer-based membrane, using the same method as in Example 1.

[0063] The carbon nanotube electrocatalytic membranes prepared achieved removal rates of 51.53% (SDZ), 52.66% (SMZ), and 56.45% (SMX) for the three antibiotics.

[0064] Results analysis: Compared with Example 1, the carbon nanotube electrocatalytic membrane without controlled defects showed a lower removal rate of antibiotics, confirming that the introduction of defects is beneficial to improving the antibiotic degradation performance.

[0065] By comparing Example 1 and Comparative Examples 2-3, it is shown that introducing defects into carbon nanotubes requires two steps: ammonium persulfate oxidation and annealing reduction. The defects in the carbon nanotubes after direct annealing in Comparative Example 2 are compared to those in the original carbon nanotubes (defect level). I D / I G =1.00, as Figure 1 Compared to (c) in Example 1, there was no improvement, and the defects of the carbon nanotubes in Comparative Example 3, which were only in contact with ammonium persulfate-hydrochloric acid solution, were not significantly improved compared to the original carbon nanotubes. Only after the above two steps of treatment, i.e., the carbon nanotubes in Example 1, did the degree of defect significantly improve.

[0066] In Comparative Example 4, the ammonium persulfate concentration was too low, and the antibiotic removal rate did not improve significantly. In Comparative Example 5, the ammonium persulfate concentration was too high, and the antibiotic removal rate did not improve much, presumably because excessive defects affected the conductivity of the carbon nanotubes. Comparative Examples 4 and 5 demonstrate that the ammonium persulfate concentration affects defect formation, thereby affecting the degradation performance of the electrocatalytic membrane for antibiotics.

[0067] Comparative Example 6, compared to Example 1, illustrates the necessity of the carboxyl functional group. Ammonium persulfate-hydrochloric acid solution is not a strong oxidizing condition. For carbon nanotubes without any functional groups, their carbon lattice structure is relatively robust and not easily oxidized by ammonium persulfate-hydrochloric acid solution, thus preventing the introduction of numerous defects. The combination of ammonium persulfate-hydrochloric acid solution and carboxylated carbon nanotubes allows for the oxidation of carbon nanotubes without the use of strong oxidizing acids, under milder and safer reaction conditions.

[0068] The excessively high carboxyl content of the carboxylated carbon nanotubes used in Comparative Example 7 was actually detrimental to antibiotic degradation. This may be because the initial lattice structure of the highly carboxylated carbon nanotubes was significantly damaged, and the damage became even more severe after oxidation and annealing with ammonium persulfate. Too many defects are not conducive to the oxidation of antibiotics.

[0069] In Comparative Example 8, the removal rate of antibiotics decreased when carboxylated carbon nanotubes were oxidized with concentrated nitric acid. This may be because the oxidizing power of nitric acid was too strong, resulting in an excessive number of defects, which was not conducive to the oxidation of antibiotics.

[0070] It is evident that the defect level of carbon nanotubes is related to annealing, ammonium persulfate concentration, the amount of carboxyl groups in the carbon nanotubes, and the type of acid. Only by following the scheme of this application, that is, using ammonium persulfate-hydrochloric acid solution in combination with carboxylated carbon nanotubes and performing annealing treatment, can a defect-rich carbon nanotube electrocatalytic membrane with better antibiotic preparation effect be prepared.

[0071] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a defect-rich carbon nanotube electrocatalytic membrane, characterized in that: The method includes the following steps: S1. Oxidation of carbon nanotubes by ammonium persulfate: Carboxylated carbon nanotubes were immersed in an ammonium persulfate-hydrochloric acid solution and ultrasonically treated. The product was centrifuged, washed several times with deionized water, and dried to obtain oxidized carbon nanotubes. The concentration of ammonium persulfate in the ammonium persulfate-hydrochloric acid solution was 0.1~0.5 mol / L, and the concentration of hydrochloric acid was 1~4 mol / L. The concentration of carboxylated carbon nanotubes in the ammonium persulfate-hydrochloric acid solution was 5~10 g / L. The carboxyl content of the carboxylated carbon nanotubes was 2%~3%, and the length of the carbon nanotubes was 10~30 µm. The ultrasonic conditions were: 500~800 W for 30~40 min. S2. Annealing and Reduction of Carbon Oxide Nanotubes: The carbon oxide nanotubes obtained in S1 were transferred to a tube furnace and annealed at 1000-1200℃ for 1 hour in a nitrogen atmosphere. Afterwards, they were washed with deionized water and dried to obtain defect-rich carbon nanotubes. The defect level of the carbon nanotubes... I D / I G =1.3~1.5; heating and cooling rates are 5℃ / min; S3. Load defect-rich carbon nanotubes onto a polymer base film to obtain a defect-rich carbon nanotube electrocatalytic membrane.

2. The method for preparing the defect-rich carbon nanotube electrocatalytic membrane according to claim 1, characterized in that: In S1, the drying conditions are: 60~70℃, 10~12h.

3. The method for preparing the defect-rich carbon nanotube electrocatalytic membrane according to claim 1, characterized in that: In S2, the drying conditions are: 60~70℃, 10~12h.

4. The method for preparing the defect-rich carbon nanotube electrocatalytic membrane according to claim 1, characterized in that: The method for loading defect-rich carbon nanotubes onto polymer base films is vacuum filtration, or crosslinking the carbon nanotube layer with a crosslinking agent after vacuum filtration, with the carbon nanotubes loaded on the upper or lower surface of the polymer base film.

5. The method for preparing a defect-rich carbon nanotube electrocatalytic membrane according to claim 1, characterized in that: The polymer-based membrane has a pore size of 0.02~0.22µm and is made of polyethersulfone or polyvinylidene fluoride.

Images