Oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled polyaniline conductive polymer and preparation method and application thereof
By preparing an oxygen reduction catalyst that couples carbon nanotubes/covalent organic framework compounds with polyaniline conductive polymers, the stability and conductivity issues of MFC cathode materials were solved, and highly efficient oxygen reduction reaction performance was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- QUFU NORMAL UNIV
- Filing Date
- 2023-07-27
- Publication Date
- 2026-05-19
AI Technical Summary
Existing MFC cathode materials suffer from poor stability and reproducibility in improving oxygen reduction reaction activity, and the low conductivity of covalent organic framework compounds limits their electrochemical performance.
Carbon nanotube/covalent organic framework compounds were prepared by solvothermal synthesis and polyaniline was coated on their surface using in-situ chemical oxidative polymerization to form PANI@COF-CNT materials, which were then used as cathode catalysts for MFCs.
This improved the electrochemical performance of the MFC cathode, enhanced the oxygen reduction catalytic activity, reduced costs, and improved the conductivity and stability of the material.
Smart Images
Figure CN116845254B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of fuel cell science and technology, specifically relating to an oxygen reduction catalyst of carbon nanotubes / covalent organic framework compound coupled with polyaniline conductive polymer, its preparation method and application. Background Technology
[0002] Microbial fuel cells (MFCs), as a novel energy conversion device, can generate electricity using organic wastewater as fuel. However, low power density is a major bottleneck restricting their large-scale application. The power generation performance of MFCs is closely related to electrode materials, the microecological environment of the cathode and anode, electrogenic microorganisms, MFC structure, and operating conditions. Among these, the coverage and renewal of the electron transport carrier and the cathode catalyst of the electrogenic microorganisms are key factors affecting MFC power generation performance, directly determining the metabolic growth of the electrogenic microorganisms and the electron transport and output power of the electrodes. According to current research, modifying electrode materials is the main scientific strategy for improving MFC power generation efficiency. However, the modification of MFC cathode materials has always been a challenging and hot research topic.
[0003] Modifying MFC cathodes with catalysts such as carbon nanotubes (CNTs) and activated carbon (AC) is an effective strategy to improve the activity of the oxygen reduction reaction (ORR) in MFC cathodes. However, these materials are difficult to simultaneously meet the required performance, are prone to accumulation and detachment from the electrode surface, resulting in poor stability and reproducibility. In recent years, covalent organic frameworks (COFs) have been widely used in catalysis, adsorption, separation, and sensing due to their significant catalytic activity, permanent porosity, high stability, good biocompatibility, and designable structures. As a suitable electrode modification material, COFs have a larger specific surface area, providing more contact points for functional reactions. However, electron localization on heteroatom bonds and framework defects caused by insufficient reversible condensation interrupt the extended π-electron conjugation, leading to low conductivity of COFs and limiting their electrochemical performance. Summary of the Invention
[0004] To address the shortcomings of existing technologies, the present invention aims to provide an oxygen reduction catalyst (ORR) of carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers, its preparation method, and its applications. This invention prepares COF via solvothermal synthesis and combines it with carbon nanotubes. Then, it uses in-situ chemical oxidative polymerization to prepare polyaniline-coated carbon nanotube / covalent organic framework compound materials, forming a PANI@COF-CNT functional material with both high conductivity and porosity to modify fuel cell cathodes and improve the electrochemical performance of MFC cathodes. The method of this invention is simple, easy to implement, and low in cost. The prepared carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer oxygen reduction catalyst exhibits superior ORR catalytic performance and can be used as an MFC cathode catalyst.
[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:
[0006] In a first aspect, the present invention provides a method for preparing an oxygen reduction catalyst of carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers, comprising the following steps:
[0007] 1. Dissolve thionine and 1,3,5-tris(p-formylphenyl)benzene in a mixture of 1,4-dioxane, mesitylene and N,N-dimethylacetamide. Add carbon nanotubes to the mixture, stir thoroughly, pour it into a Teflon reaction vessel, add acetic acid to the mixture, and seal the Teflon reaction vessel in a stainless steel autoclave for heating.
[0008] 2. After cooling, centrifugation was performed to obtain a precipitate. The precipitate was washed with N,N-dimethylformamide, and the washed precipitate was immersed in tetrahydrofuran to exchange the solvent. The precipitate was collected and named COF-CNT.
[0009] 3. Prepare two portions of sulfuric acid. Add aniline solution to one portion and ammonium persulfate powder to the other portion. After they are completely dissolved, mix them quickly and then add the COF-CNT material. After the reaction is complete, you will get the PANI@COF-CNT oxygen reduction catalyst.
[0010] In a second aspect, the present invention provides an oxygen reduction catalyst for carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers obtained by the preparation method described in the first aspect.
[0011] Thirdly, the present invention provides the application of the oxygen reduction catalyst of the carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer as described in the second aspect as an MFC cathode catalyst.
[0012] The beneficial effects achieved by one or more technical solutions of the present invention are as follows:
[0013] 1. This invention is low in cost, using thionine, 1,3,5-tris(p-formylphenyl)benzene and carbon nanotubes as raw materials, with low equipment requirements and good operability.
[0014] 2. The present invention uses a solvothermal synthesis method and an in-situ chemical oxidative polymerization method to prepare catalyst materials. This method is simple and easy to implement, and the oxygen reduction catalyst prepared by carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers has a large specific surface area and strong conductivity.
[0015] 3. The oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer obtained in this invention has good oxygen reduction catalytic activity and can be used to improve the ORR performance of fuel cells and reduce the cost of use. Attached Figure Description
[0016] 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 improper limitation of the invention.
[0017] Figure 1 This is a schematic flowchart of the preparation method of the oxygen reduction catalyst (PANI@COF-CNT) of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer prepared in Example 1 of the present invention;
[0018] Figure 2 This is a SEM image of the oxygen reduction catalyst (PANI@COF-CNT) of carbon nanotubes / covalent organic framework compound coupled with polyaniline conductive polymer prepared in Example 1 of this invention. Figure 2 a is an SEM image of a covalent organic framework compound. Figure 2 b is a SEM image of carbon nanotubes. Figure 2 c is a SEM image of the carbon nanotube / covalent organic framework compound. Figure 2 d is a SEM image of a covalent organic framework compound coupled to a polyaniline conductive polymer. Figure 2 e is a SEM image of a carbon nanotube / covalent organic framework compound coupled with a polyaniline conductive polymer;
[0019] Figure 3 The FT-IR and XRD patterns of the carbon nanotube / covalent organic framework compound coupled with the polyaniline conductive polymer in the oxygen reduction catalyst prepared in Example 1 of this invention are as follows: Figure 3 a is the FT-IR spectrum of the redox agent. Figure 3 b is the XRD pattern of the redox agent;
[0020] Figure 4 XPS image of the oxygen reduction catalyst (PANI@COF-CNT) of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer prepared in Example 1 of this invention;
[0021] Figure 5 This is a nitrogen adsorption-desorption curve of the oxygen reduction catalyst (PANI@COF-CNT) of carbon nanotubes / covalent organic framework compound coupled with polyaniline conductive polymer prepared in Example 1 of the present invention. Figure 5 a is the nitrogen adsorption-desorption curve of covalent organic framework compounds. Figure 5 b is the nitrogen adsorption-desorption curve of carbon nanotubes. Figure 5 c is the nitrogen adsorption-desorption curve of carbon nanotube / covalent organic framework compound. Figure 5 d is the nitrogen adsorption-desorption curve of the covalent organic framework compound coupled to the polyaniline conductive polymer. Figure 5 e is the nitrogen adsorption-desorption curve of carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers;
[0022] Figure 6 The images show the CV and LSV curves of covalent organic framework compounds, carbon nanotubes, carbon nanotubes / covalent organic framework compounds, covalent organic framework compounds coupled with polyaniline conductive polymers, and carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers as MFC cathode catalysts in Example 2 of this invention. Figure 6 a is the CV curve of the redox agent. Figure 6 b is the LSV curve of the redox agent;
[0023] Figure 7 The power density diagrams for covalent organic framework compounds, carbon nanotubes, carbon nanotubes / covalent organic framework compounds, covalent organic framework compounds coupled with polyaniline conductive polymers, and carbon nanotubes / covalent organic framework compounds coupled with polyaniline conductive polymers as MFC cathode catalysts in Example 3 of the present invention are shown. Detailed Implementation
[0024] Covalent organic framework compounds (COFs) are high-performance electrode modification materials with large specific surface areas, providing abundant electroactive sites for functional reactions. However, their low conductivity limits their electrochemical performance. A reliable solution is to use a mixture of COFs and conductive agents as the active material of the electrode. Meanwhile, CNTs (carbon nanotubes) exhibit great potential in a wide range of applications due to their unique structural, mechanical, and electronic properties, high stability, and excellent conductivity. This study prepares COFs and incorporates them onto the surface of CNTs, then loads PANI (polyalkylene oxide) to form PANI@COF-CNT functional materials that combine high conductivity and porosity to modify cathodes and improve the electrochemical performance of MFCs (molecular fuel cells). PANI@COF-CNTs hold promise as an excellent oxygen reduction catalyst, providing a powerful impetus for exploring fuel cells with good electrochemical performance.
[0025] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.
[0026] Example 1
[0027] Please see Figure 1 , Figure 1 This is a schematic flowchart of the preparation method of the oxygen reduction catalyst (PANI@COF-CNT) of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer prepared in this invention.
[0028] like Figure 1 As shown, in a first typical embodiment of the present invention, a method for preparing a carbon nanotube / covalent organic framework compound coupled polyaniline conductive polymer oxygen reduction catalyst includes the following steps:
[0029] Step 1: Dissolve 0.45g of thionine and 0.4g of 1,3,5-tris(p-formylphenyl)benzene in 150mL of a mixture of 1,4-dioxane, mesitylene, and N,N-dimethylacetamide (volume ratio 1:1:1). Then add 0.525g of carbon nanotubes and pour the mixture into a 200mL Teflon reaction vessel. Add 10mL of 6M acetic acid to the mixture, seal the Teflon reaction vessel in a stainless steel autoclave, and heat at 120℃ for 72 hours.
[0030] Step 2: After cooling to room temperature, the precipitate was obtained by centrifugation at 10,000 rpm. The precipitate was washed with N,N-dimethylformamide until the supernatant was colorless. The washed precipitate was then immersed in tetrahydrofuran for 6 hours to exchange the solvent. Finally, the precipitate was collected and dried in a freeze dryer, and named COF-CNT.
[0031] Step 3: Add 4.6 μL of aniline to 5 mL of H₂SO₄ and sonicate until completely dissolved. Add 0.003 g of ammonium persulfate to another 5 mL of H₂SO₄ and sonicate until completely dissolved. After cooling both solutions to 0 °C, mix them rapidly, and then add the prepared COF-CNT composite material. After reacting in an ice bath for 8 hours, the carbon nanotube / covalent organic framework compound coupled polyaniline conductive polymer oxygen reduction catalyst is obtained.
[0032] Step 4: Morphological and structural characterization of the prepared carbon nanotube / covalent organic framework compound coupled polyaniline conductive polymer (PANI@COF-CNT) oxygen reduction catalyst was performed, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption tests.
[0033] SEM images of the covalent organic framework compound, carbon nanotubes, carbon nanotubes / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotubes / covalent organic framework compound coupled with polyaniline conductive polymer prepared in step three of this embodiment are shown below. Figure 2 As shown. COF is a large-scale two-dimensional (2D) nanoframework in the shape of coral bone. Figure 2 a), while CNTs exhibit a unique nanotube structure with a size of approximately 39 nm. Figure 2 b). By Figure 2 As shown in c, CNTs aggregate and distribute on the surface of the composite material, resulting in significant changes in the morphology and size of the composite material. From Figure 2 As can be seen, the morphology of the PANI composite material is significantly different from that of the original COF and CNT. Due to the combination of polyaniline and porous framework, PANI@COF and PANI@COF-CNT possess a uniformly distributed complex network structure. A polyaniline layer was grown on the surface of COF and COF-CNT through chemical oxidative polymerization, resulting in a rougher surface morphology for the composite material. This indicates that the oxygen reduction catalyst improves the utilization rate of PANI@COF-CNT by reducing the diffusion distance and promoting charge transfer.
[0034] The FT-IR and XRD patterns of the covalent organic framework compound, carbon nanotubes, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer prepared in step three of this embodiment are as follows: Figure 3 As shown. By Figure 3 As can be seen from this, the characteristic absorption peak (~3433 cm⁻¹) generated by the OH vibration of PANI@COF and PANI@COF-CNT is present. -1The peak intensity is the highest, which may be related to the incorporation of polyaniline. In the FT-IR absorption spectra of COF-CNT and PANI@COF-CNT, the peak intensity is highest at 1630 cm⁻¹. -1 C=C stretching bands were found nearby, indicating that CNTs were successfully grown on COF and PANI@COF. The FT-IR spectra of PANI@COF and PANI@COF-CNTs were observed at 789 cm⁻¹. -1 and 1022cm -1 The presence of this substance further confirms the presence of polyaniline, demonstrating the successful loading of the conductive polymer. Figure 3 As shown in b, a large number of characteristic peaks were observed in the prepared materials, indicating the excellent crystallinity of COF. For COF-CNT, the characteristic peak at 26.1° corresponds to the (002) crystal plane of CNTs, indicating that the CNT layer was successfully bonded to COFs. After being coated with PANI, the PANI@COF and PANI@COF-CNT samples showed obvious peaks at 20.7° and 24.9° on the (020) and (200) planes, respectively, which belong to PANI. This can be attributed to the successful formation of polyaniline on COF and COF-CNT. The above results all indicate the successful preparation of PANI@COF and PANI@COF-CNT.
[0035] The XPS image of the carbon nanotube / covalent organic framework compound coupled with the polyaniline conductive polymer obtained in step three of this embodiment is shown below. Figure 4 As shown. By Figure 4 It is known that the prepared PANI@COF-CNT composite material contains C, N, O, and S elements. The three sub-peaks of N 1s at 398.9 eV, 399.9 eV, and 400.8 eV are assigned to C=N, CN, and C-NH2, respectively, indicating that the combination of PANI and COF-CNT gives PANI@COF-CNT various redox properties and doping-dedoping capabilities. In the 2p fine spectrum of S, three characteristic peaks at 163.6, 164.5, and 168.9 eV can be observed. The first two peaks are connected to CS, which is obtained by the spin orbital splitting of thiophene sulfur atoms incorporated into the carbon framework. The last peak at 168.9 eV may be derived from some sulfur oxides. These results further demonstrate the in-situ introduction of polyaniline onto COF-CNT, confirming the successful synthesis of a carbon nanotube / covalent organic framework compound coupled polyaniline conductive polymer oxygen reduction catalyst.
[0036] The nitrogen adsorption-desorption curves of the covalent organic framework compound, carbon nanotubes, carbon nanotubes / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotubes / covalent organic framework compound coupled with polyaniline conductive polymer prepared in step three of this embodiment are shown in the figure below. Figure 5 As shown. By Figure 5 It can be seen that the isotherms of all oxygen reduction catalysts are type III isotherms, indicating the existence of reversible reactions and weak interactions between the adsorbent and its surface. Furthermore, the specific surface area of COF is 140.668 m². 2 / g, after being loaded onto the PANI surface, its specific surface area decreased to 7.529m² due to the blockage of some pores in the hybrid material. 2 The concentration of polyaniline (m² / g) indicates a strong interaction between COF and PANI. Furthermore, compared to COF-CNT, the addition of polyaniline reduces its specific surface area and increases its pore size, which is beneficial for improving its electrical conductivity. The specific surface area of COF-CNT is 174.480 m² / g. 2 The specific surface area of PANI@COF-CNT was 1.240 times that of COF and 1.377 times that of CNT, respectively. Furthermore, the specific surface area and pore size of PANI@COF-CNT were 13.220 times and 1.913 times that of PANI@COF, respectively, indicating that the introduction of carbon nanotubes can alter the number and size of pores in COF and PANI@COF, thereby significantly increasing their specific surface area and pore size.
[0037] Example 2
[0038] The oxygen reduction activity of the carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer (PANI@COF-CNT) oxygen reduction catalyst prepared in Example 1 was tested as the MFC cathode catalyst. Specifically, a conventional three-electrode system was used to determine the oxygen reduction activity of covalent organic framework compound, carbon nanotube, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer as MFC cathode catalysts. CV and LSV curves for different oxygen reduction catalysts were plotted. Both CV and LSV experiments were performed in 50 mM PBS solution.
[0039] The CV and LSV curves of the covalent organic framework compound, carbon nanotubes, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer oxygen reduction catalyst used in this embodiment are shown below. Figure 6 As shown. By Figure 6 As shown in Figure a, at a scan rate of 100 mV / s, the surface area of PANI@COF-CNT is larger than that of other catalysts. This is due to the increased contact area between PANI@COF-CNT and the electrolyte. The conductivity of polyaniline interacts with the rapid ion migration of COF-CNT, promoting electron transfer. Figure 6As shown in Figure a, two pairs of redox peaks were observed near -0.3 V and -0.1 V on PANI@COF-CNT. Characteristic peaks are present in COF-CNT but not on COF, indicating that the peaks on COF-CNT are related to electroactive CNTs. Compared to COF-CNT, the current of PANI@COF-CNT is significantly increased, which may be due to the addition of the electrochemically active polymer polyaniline, which significantly improves the electrochemical performance of the composite material. To further investigate the electrocatalytic activity of the composite catalyst, the LSV curves of different catalysts were examined. Figure 6 As can be seen from b, the slope order of the LSV curves for different oxygen reduction catalysts is PANI@COF-CNT>CNT>COF>PANI@COF>COF-CNT. Compared with COF-CNT, the LSV slope of PANI@COF-CNT indicates that a larger current is generated at the same cathode potential, thereby improving the ORR activity. These results suggest that this carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer oxygen reduction catalyst has good application potential under actual fuel cell operating conditions.
[0040] Example 3
[0041] The covalent organic framework compound, carbon nanotubes, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer prepared in Example 1 were used as cathode catalysts for MFC electrochemical performance testing. Specifically, the following methods were employed: covalent organic framework compound, carbon nanotubes, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer were used as cathode catalysts in a single-chamber MFC, while maintaining a consistent anode potential, to evaluate the impact of different cathode oxygen reduction catalysts on the power generation performance of the fuel cell. By gradually reducing the external resistance of the fuel cell (from 3000Ω to 10Ω), and after the voltage stabilized, the values were recorded and the power density curve of the MFC was plotted.
[0042] The power density curves of the covalent organic framework compound, carbon nanotubes, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer oxygen reduction catalyst used in this embodiment are shown in the figure below. Figure 7 As shown. By Figure 7It can be seen that after modifying the cathode with PANI@COF-CNT composite material as an oxygen reduction catalyst, the performance of the MFC is PANI@COF-CNT > PANI@COF > COF-CNT > CNT > COF. The maximum power density generated by PANI@COF-CNT is 194.480 mW / m³. 2 It is a COF-CNT cathode (78.178mW / m 2 It is 2.488 times that of COF MFC (22.471mW / m 2 The superior performance of the PANI@COF-CNT-based MFC is 8.655 times that of the standard MFC. This is because the PANI@COF-CNT electrode is well-suited as the air cathode for the MFC, demonstrating that PANI@COF-CNT is an excellent electrode material.
[0043] Table 1 shows the voltage-time graphs of the covalent organic framework compound, carbon nanotubes, carbon nanotube / covalent organic framework compound, covalent organic framework compound coupled with polyaniline conductive polymer, and carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer oxygen reduction catalysts used in this embodiment. PANI@COF-CNT can generate a voltage of 0.41V, while the maximum output voltages of COF MFC, CNT MFC, COF-CNT MFC, and PANI@COF MFC are 0.19V, 0.27V, 0.29V, and 0.35V, respectively. The voltage value is positively correlated with the glucose consumption rate, indicating that the PANI@COF-CNT MFC cathode achieved a rapid and effective ORR. The output voltage of PANI@COF-CNT-MFC changed very little over 5 days, stabilizing at around 0.39V, indicating the stability and durability of the PANI@COF-CNT catalyst. This is primarily due to the uniformly distributed lattice structure formed by PANI@COF-CNT, which increases the surface area and the number of electrochemically active sites, thereby promoting electron transfer on the PANI@COF-CNT electrode. Therefore, PANI@COF-CNT achieves superior electrochemical efficiency and long lifespan.
[0044] Table 1 Voltage-Time Tables for Different Redox Agents
[0045]
Claims
1. A method for preparing an oxygen reduction catalyst of carbon nanotubes / covalent organic framework compound coupled with polyaniline conductive polymer, characterized in that, Includes the following steps: (1) Weigh 0.45g thionine and 0.4g 1,3,5-tris(p-formylphenyl)benzene and dissolve them in 150 mL of a mixture of 1,4-dioxane, mesitylene and N,N-dimethylacetamide in a volume ratio of 1:1:
1. Add 0.525g carbon nanotubes (CNTs), stir thoroughly, pour into a Teflon reaction vessel, add 10 mL of 6M acetic acid to the mixture, seal the Teflon reaction vessel in a stainless steel autoclave, and heat at 120°C for 72 h. (2) After cooling, centrifugation was used to obtain the precipitate. The precipitate was washed with N,N-dimethylformamide until the supernatant was colorless. The washed precipitate was immersed in tetrahydrofuran for 6 hours to exchange the solvent. The COF-CNT precipitate was collected and dried in a freeze dryer for 48 hours. (3) Prepare two equal 5 mL sulfuric acid solutions. Add 4.6 μL aniline to one solution and 0.003 g ammonium persulfate powder to the other solution. Sonicate until completely dissolved. After cooling the two solutions to 0℃, mix them quickly and then add the COF-CNT material prepared in step (2). After the reaction is complete, the PANI@COF−CNT oxygen reduction catalyst is obtained.
2. The method for preparing the oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer as described in claim 1, characterized in that, In step (1), the mixed solution is poured into a 200 mL Teflon reaction tank.
3. The method for preparing the oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer as described in claim 1, characterized in that, In step (2), the precipitate was obtained by centrifugation at 10,000 rpm.
4. The method for preparing the oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer as described in claim 1, characterized in that, In step (3), 0.05 g of COF-CNT is added to the mixed solution.
5. The method for preparing the oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer as described in claim 1, characterized in that, In step (3), after reacting in an ice bath for 8 hours, the catalyst was washed three times with deionized water and dried under vacuum at 60°C for 12 hours to obtain the PANI@COF−CNT oxygen reduction catalyst.
6. The application of an oxygen reduction catalyst of carbon nanotube / covalent organic framework compound coupled with polyaniline conductive polymer prepared by the preparation method according to any one of claims 1-5 as a cathode catalyst for fuel cells.