MOF-Derived Anode Materials for AEM Water Electrolysis, Their Laser Preparation Methods and Applications

Abstract

The present invention discloses an AEM electrolytic water anode material derived from MOF and its laser preparation method and application. First, the ZIF-67(Co) material is formed by mechanical stirring method, and after adding Fe-Phen, it is quantitatively loaded on the carbon paper. A network-like alloy material is formed through direct laser scribing technology. The network-like structure leads to the exposure of more active sites, and the formed Co and Fe alloys have a promoting effect on the OER performance, solving the problems of poor conductivity and low electrocatalytic activity of the original MOF material. At the same time, the electrocatalyst and the electrode are integrally formed, avoiding the complex processes and adverse factors brought by the loading of powder catalyst materials. The material prepared by the present invention has an overpotential as high as 250 mV in electrocatalytic tests, and has excellent electrocatalytic activity and stability.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrolyzed water devices and electrolyzed water processes, and particularly relates to a MOF-derived oxygen evolution catalyst and a preparation method and application thereof by laser rapid heating. Background Art

[0002] We are urgently in need of developing renewable energy to reduce the dependence on fossil fuels. Hydrogen energy has always been recognized as the most potential green energy carrier, with characteristics such as high energy density, light mass and easy transportation, clean and pollution-free energy release process, and rich reserves. It is an important raw material for fertilizer production, oil refining and hydrogenation in industry. Producing "green hydrogen" through electrocatalytic water splitting is a sustainable method with high efficiency and broad application prospects.

[0003] The electrolyzed water processes mainly include alkaline water electrolysis (AWE), proton exchange membrane (PEM), and anion exchange membrane (AEM), etc. AEM has attracted extensive attention due to its high hydrogen production efficiency and lower cost-benefit compared with PEM (transition metal catalysts can be used instead of platinum group metal catalysts, the membrane used in AEM electrolysis is cheaper than Nafion membrane, and stainless steel can be used instead of Ti as the porous transport layer and bipolar plate in AEM electrolysis). In AEM electrolyzed water devices, the electrocatalyst greatly affects the efficiency of hydrogen production by electrolyzed water. Therefore, designing and preparing electrocatalysts with high activity and stability is of great significance for promoting the development of electrolyzed water. Metal-organic framework (MOF) materials can be used as good precursors for synthesizing efficient catalysts due to their advantages such as high specific surface area, adjustable pore size, and well-defined metal nodes. Composites based on three-dimensional transition metals such as iron, cobalt, and nickel can generally be used as OER catalysts to replace commercial noble metals.

[0004] Direct laser scribing technology is an advanced printing technology that can convert non-conductive substances into active electrode materials by laser according to a set pattern. Compared with traditional methods, this preparation method is faster, has lower costs, and can print fine patterns with high precision. We hereby propose a method of using MOF materials as precursors, introducing metal iron-1,10-phenanthroline complex (Fe-Phen), and rapidly heating through direct laser scribing technology to prepare electrocatalysts with high activity and stability for electrolyzed water. Summary of the Invention

[0005] The present invention provides a MOF-derived AEM electrolytic water anode material, a preparation method thereof, and an application. The present invention mixes ZIF-67 with Fe-Phen and prepares a high-activity and stable anode electrode for AEM electrolytic water by direct laser scribing, selects and optimizes process parameters and raw material types during the preparation process, and solves the problems of scarcity, high price, and low catalytic efficiency of traditional noble metal catalysts, as well as the complex preparation process of loading powder catalysts onto electrodes and the introduction of binders to reduce the conductivity between the catalyst and the carrier.

[0006] The technical solution of the present invention is as follows:

[0007] A preparation method of a MOF-derived AEM electrolytic water anode material, comprising the following steps:

[0008] (1) Preparation of ZIF-67: Mix a cobalt nitrate hexahydrate solution with a 2-methylimidazole solution, let it stand at room temperature, and then centrifuge and wash to obtain ZIF-67;

[0009] The mass ratio of cobalt nitrate hexahydrate to 2-methylimidazole is 0.58 - 2.89:0.66 - 3.29, preferably 1.82:2.06;

[0010] The preparation method of the cobalt nitrate hexahydrate solution is: Add cobalt nitrate hexahydrate to a mixed solvent of methanol and ethanol with a volume ratio of 1:1, stir evenly at room temperature, and that's it; the concentration of the cobalt nitrate hexahydrate solution is 0.02 - 0.1 M, preferably 0.063 M;

[0011] The preparation method of the 2-methylimidazole solution is: Add the 2-methylimidazole solution to a mixed solvent of methanol and ethanol with a volume ratio of 1:1, stir evenly at room temperature, and that's it; the concentration of the 2-methylimidazole solution is 0.08 - 0.4 M, preferably 0.25 M;

[0012] Specifically, the operation method of step (1) is as follows: Simultaneously inject the cobalt nitrate hexahydrate solution and the 2-methylimidazole solution into the reaction vessel, stir vigorously at 500 - 800 rpm (preferably 700 rpm) for 30 s, let it stand at room temperature for 18 - 24 h (preferably 22 h), centrifuge the suspension and wash it with ethanol 3 times, and the obtained precipitate is ZIF-67;

[0013] (2) Preparation of L-Fe-Co / C-CP: Stir ZIF-67, ferrous inorganic salt, and 1,10-phenanthroline monohydrate obtained in step (1) evenly in a mixed solvent of ethanol and water. Centrifuge the obtained suspension, add ethanol to the precipitate and disperse it evenly by ultrasonic treatment. Drop the obtained dispersion evenly on the surface of carbon paper. The material obtained after ethanol evaporation is denoted as Fe-ZIF-67-CP. Perform carbonization treatment on Fe-ZIF-67-CP by direct laser scribing to obtain the MOF-derived AEM electrolytic water anode material, denoted as L-Fe-Co / C-CP;

[0014] Preferably, the ferrous inorganic salt is ferrous sulfate heptahydrate;

[0015] The mass ratio of ZIF-67, 1,10-phenanthroline monohydrate, and ferrous inorganic salt is 1:0.8 - 1.2:0.6 - 1, preferably 1:1:0.82;

[0016] In the mixed solvent of ethanol and water, the volume ratio of ethanol to water is 1 - 3:1, preferably 2:1;

[0017] Specifically, ZIF-67, ferrous inorganic salt, and 1,10-phenanthroline monohydrate are stirred at room temperature in a mixed solvent of ethanol and water for 2 - 4 h (preferably 3 h) at a stirring speed of 200 - 400 rpm (preferably 300 rpm);

[0018] The dropping amount of the dispersion on the surface of carbon paper is 3 - 8 mg / cm -2 in terms of solid content, preferably 6 mg / cm -2 ;

[0019] The parameter settings for direct laser scribing are as follows: laser power 1.7 - 10.2 W (preferably 5.59 W), scribing spacing 100 - 180 μm (preferably 150 μm).

[0020] The present invention relates to a MOF-derived AEM electrolytic water anode material prepared by the above preparation method.

[0021] The MOF-derived AEM electrolytic water anode material of the present invention can be used in the reaction of electrolyzing water. The MOF-derived AEM electrolytic water anode material can be assembled as an anode in an AEM electrolytic water device for electrolyzing water tests.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention provides an AEM electrolytic water anode material derived from MOF. First, ZIF-67 is synthesized, and it is found by SEM that the morphology of ZIF-67 is dodecahedron. After introducing metal Fe element, it is loaded on carbon paper and carbonized by direct laser scribing technology. It is found by characterizations such as SEM and HRTEM that the morphology of ZIF-67 has changed drastically, from the original dodecahedron to a network-like structure, exposing more active sites and having high catalytic activity.

[0024] The electrode material of the present invention, which is a mixture of MOF material ZIF-67 and Fe-Phen and carbonized by direct laser scribing technology, has good catalytic activity and stability, and the method of the present invention is simple, easy to implement, low in cost and can be mass-produced. Brief Description of the Drawings

[0025] Figure 1 : Scanning electron micrograph of ZIF-67 in Examples 1-14.

[0026] Figure 2 : Scanning electron micrograph of Fe-ZIF-67 in Example 2.

[0027] Figure 3 : Scanning electron micrograph of Sample 1 in Example 1.

[0028] Figure 4 : Scanning electron micrograph of Sample 2 in Example 2.

[0029] Figure 5 : Scanning electron micrograph of Sample 3 in Example 3.

[0030] Figure 6 : Scanning electron micrograph of Sample 4 in Example 4.

[0031] Figure 7 : Electro-catalytic efficiency diagrams of Sample 1, Sample 2, Sample 3, Sample 4, and Sample 5.

[0032] Figure 8 : Electrochemical impedance diagrams of Sample 1, Sample 2, Sample 3, Sample 4, and Sample 5.

[0033] Figure 9 : Diagram of the electrolytic cell voltage stability of the AEM electrolytic water device assembled with Sample 1 as the anode at 10 mA cm -2 under. Detailed Description of the Invention

[0034] The technical solutions of the present invention will be further described in detail below in conjunction with specific embodiments, which are explanations of the present invention rather than limitations.

[0035] In the following examples, the carbon paper is from Suzhou Shengnuoke Technology Co., Ltd., with the brand of Toray and the model of TGP-H-060, a relatively hydrophilic carbon paper.

[0036] Example 1:

[0037] 1.82 g of cobalt nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left standing at room temperature for 22 h (the same standing time hereinafter). After centrifugation and washing, ZIF-67 was obtained.

[0038] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 (40 mL of ethanol and 20 mL of water, the same for other examples) for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP (M is Fe, the same hereinafter). Through the direct laser scribing technique, sample 1 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm.

[0039] Example 2:

[0040] 1.82 g of cobalt nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left standing at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0041] 200 mg of ZIF-67, 13.9 mg of ferrous sulfate heptahydrate, and 29.73 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through the direct laser scribing technique, sample 2 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm.

[0042] Example 3:

[0043] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0044] 200 mg of ZIF-67, 55.6 mg of ferrous sulfate heptahydrate, and 118.9 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through the direct laser scribing technique, the M-ZIF-67-CP was carbonized with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm to obtain Sample 3.

[0045] Example 4:

[0046] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0047] 200 mg of ZIF-67, 333.6 mg of ferrous sulfate heptahydrate, and 713.4 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through the direct laser scribing technique, the M-ZIF-67-CP was carbonized with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm to obtain Sample 4.

[0048] Example 5:

[0049] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0050] After uniformly dispersing ZIF-67 by ultrasonic treatment, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as ZIF-67-CP. Through direct laser scribing technology, sample 5 was obtained by carbonizing ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm.

[0051] Example 6:

[0052] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0053] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 158.53 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through direct laser scribing technology, sample 6 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm.

[0054] Example 7:

[0055] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0056] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through direct laser scribing technology, sample 7 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 3.4 W and a scribing spacing of 150 μm.

[0057] Example 8:

[0058] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0059] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through direct laser scribing technology, M-ZIF-67-CP was carbonized with laser parameters such as a laser power of 5.59 W and a scribing spacing of 150 μm to obtain Sample 8.

[0060] Example 9:

[0061] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0062] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through direct laser scribing technology, M-ZIF-67-CP was carbonized with laser parameters such as a laser power of 8.5 W and a scribing spacing of 150 μm to obtain Sample 9.

[0063] Example 10:

[0064] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left to stand at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0065] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through direct laser scribing technology, the M-ZIF-67-CP was carbonized with laser parameters such as a laser power of 11.05 W and a scribing spacing of 150 μm to obtain Sample 10.

[0066] Example 11:

[0067] 1.82 g of cobalt nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left standing at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0068] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper, denoted as M-ZIF-67-CP. Through direct laser scribing technology, the M-ZIF-67-CP was carbonized with laser parameters such as a laser power of 5.59 W and a scribing spacing of 120 μm to obtain Sample 11.

[0069] Example 12:

[0070] 1.82 g of cobalt nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left standing at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0071] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2It is denoted as M-ZIF-67-CP on the carbon paper. Through the direct laser scribing technique, sample 12 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 140 μm.

[0072] Example 13:

[0073] 1.82 g of cobalt(II) nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left standing at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0074] 200 mg of ZIF-67, 222.4 mg of ferrous sulfate heptahydrate, and 475.6 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper and denoted as M-ZIF-67-CP. Through the direct laser scribing technique, sample 13 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 160 μm.

[0075] Example 14:

[0076] 1.82 g of zinc nitrate hexahydrate was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. 2.06 g of 2-methylimidazole was added to 100 mL of a mixed solution of methanol and ethanol with a volume ratio of 1:1 and mixed evenly. The above two solutions were simultaneously injected into a glass bottle, stirred vigorously, and then left standing at room temperature. After centrifugation and washing, ZIF-67 was obtained.

[0077] 200 mg of ZIF-67, 164 mg of ferrous sulfate heptahydrate, and 200 mg of 1,10-phenanthroline monohydrate were magnetically stirred in a mixed solution of ethanol and water with a volume ratio of 2:1 for 3 h to obtain a suspension. After centrifugation, an ethanol solution was added. After ultrasonic homogenization, 6 mg was quantitatively dropped onto a 1×1 cm -2 carbon paper and denoted as M-ZIF-67-CP. Through the direct laser scribing technique, sample 14 was obtained by carbonizing M-ZIF-67-CP with laser parameters such as a laser power of 5.59 W and a scribing spacing of 180 μm.

[0078] Figure 1SEM images of ZIF-67 in Examples 1-14. The observed ZIF-67 has a dodecahedral morphology with uniform particle sizes.

[0079] Figure 2 SEM image of Fe-ZIF-67 in Example 2. After doping with Fe element, the surface of the sample is slightly rough and evenly distributed.

[0080] Figure 3 SEM image of Sample 1 in Example 1. After laser treatment, the morphology of the sample has changed significantly, showing a network structure that can expose more active sites.

[0081] Figure 4 SEM image of Sample 2 in Example 2. After laser treatment, the morphology of the sample also shows a network structure.

[0082] Figure 5 SEM image of Sample 3 in Example 3. After laser treatment, the morphology of the sample also shows a network structure.

[0083] Figure 6 SEM image of Sample 4 in Example 4. After laser treatment, the morphology of the sample also shows a network structure.

[0084] Figure 7 Electrocatalytic efficiency diagrams of Sample 1, Sample 2, Sample 3, Sample 4, and Sample 5. It can be seen from the figure that different doping contents of Fe have a certain influence on the final performance. Among them, Sample 1 formed after Fe doping and laser treatment has more active sites, and the overpotential at 10 mA cm -2 is 250 mV.

[0085] Figure 8 Electrochemical impedance diagrams of Sample 1, Sample 2, Sample 3, Sample 4, and Sample 5. It can be seen from the figure that the impedance of the sample after doping with Fe decreases, and shows a trend of first decreasing and then increasing with the incorporation of Fe element. The impedance value of Sample 1 is the smallest.

[0086] Figure 9 Graph of the change in the electrolytic cell voltage of the AEM water electrolysis device assembled with Sample 1 as the anode over time. Using Sample 1 as the anode and commercial Pt / C as the cathode, its stability was tested by chronopotentiometry. It was found that at a current density of 10 mA cm -2 the cell voltage was maintained at 1.57 V. After nearly 80 h of testing, the potential change was about 20 mV. The stability is good.

[0087] The preferred embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Any experiments and technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art shall fall within the protection scope determined by the claims.

Claims

1. A method for preparing an AEM water electrolysis anode material based on MOF, characterized in that: The steps include: (1) Preparation of ZIF-67: Cobalt nitrate hexahydrate solution and 2-methylimidazole solution were mixed, allowed to stand at room temperature, and then centrifuged and washed to obtain ZIF-67; (2) Preparation of L-Fe-Co / C-CP: The ZIF-67 obtained in step (1), ferrous inorganic salt, and 1,10-phenanthroline monohydrate are uniformly stirred in a mixed solvent of ethanol and water, the obtained suspension is centrifuged, ethanol is added to the precipitate for ultrasonic dispersion, the obtained dispersion is evenly dropped on the surface of carbon paper, and the obtained material after ethanol is evaporated is recorded as Fe-ZIF-67-CP; Fe-ZIF-67-CP is carbonized by direct laser scribing to obtain the MOF-derived AEM water electrolysis anode material, which is recorded as L-Fe-Co / C-CP; The parameters of direct laser scribing were set as follows: laser power 1.7-10.2 W, scribing spacing 100-180 μm.

2. The method for preparing an AEM water electrolysis anode material based on MOF as claimed in claim 1, characterized in that: In step (1), the mass ratio of cobalt nitrate hexahydrate to 2-methylimidazole is 0.58-2.89:0.66-3.

29.

3. The method for preparing an AEM water electrolysis anode material based on MOF as claimed in claim 1, characterized in that: In step (1), the preparation method of the cobalt nitrate hexahydrate solution is: adding cobalt nitrate hexahydrate to a mixed solvent of methanol and ethanol in a volume ratio of 1:1, and stirring evenly at room temperature to obtain the cobalt nitrate hexahydrate solution; the concentration of the cobalt nitrate hexahydrate solution is 0.02-0.1M; The preparation method of the 2-methylimidazole solution is as follows: adding the 2-methylimidazole solution to a mixed solvent of methanol and ethanol in a volume ratio of 1:1, stirring evenly at room temperature, and obtaining the solution; the concentration of the 2-methylimidazole solution is 0.08-0.4M.

4. The method for preparing an AEM water electrolysis anode material based on MOF as claimed in claim 1, characterized in that: In step (1), the operation method is as follows: inject the cobalt nitrate hexahydrate solution and the 2-methylimidazole solution into the reaction container at the same time, vigorously stir at 500-800 rpm for 30 seconds, stand at room temperature for 18-24 hours, centrifuge the suspension and wash it with ethanol three times, and the resulting precipitate is ZIF-67.

5. The method for preparing an AEM water electrolysis anode material based on MOF as claimed in claim 1, characterized in that: In step (2), the ferrous inorganic salt is ferrous sulfate heptahydrate.

6. The method for preparing an AEM water electrolysis anode material based on MOF as claimed in claim 1, characterized in that: In step (2), the mass ratio of ZIF-67, 1,10-phenanthroline monohydrate and ferrous inorganic salt is 1:0.8-1.2:0.6-1.

7. The method for preparing an AEM water electrolysis anode material based on MOF as claimed in claim 1, characterized in that: In step (2), ZIF-67, ferrous inorganic salt, and 1,10-phenanthroline monohydrate are stirred in a mixed solvent of ethanol and water at room temperature for 2-4 hours at a stirring speed of 200-400 rpm.

8. A MOF-derived AEM water electrolysis anode material prepared according to the preparation method of any one of claims 1 to 7.

9. Use of the MOF-derived AEM water electrolysis anode material as claimed in claim 8 in the reaction of water electrolysis.

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