Catalytic anode with conductive polymer intercalation and method of making and use thereof

Abstract

The application discloses a kind of catalytic anode with conductive polymer intercalation and its preparation method and application, it is related to electrolytic hydrogen production technical field, comprising the following steps: step 1, by chemical deposition method on the growth of conductive polymer organic matter in nickel foam, electrode is prepared;Step 2, configuration contains nickel nitrate aqueous solution and ferric nitrate aqueous solution mixed solution as electrolyte, transfer to three-electrode electrolytic cell, with the electrode prepared in step 1 as electrolytic cell cathode, platinum wire electrode as electrolytic cell anode, carry out electrodeposition;Step 3, take out the nickel foam after electrodeposition, washing, remove surface moisture, obtain the catalytic anode with conductive polymer intercalation.The application improves the catalytic stability of seawater direct electrolysis (500+hours), and improves catalytic activity, reduces the cost of seawater electrolysis hydrogen production (reduces 37.5%), electrode synthesis process is safe and environmentally friendly, easy to operate, low cost, good portability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrolytic hydrogen production, in particular to a catalytic anode with conductive polymer intercalation and a preparation method and application thereof. BACKGROUND

[0002] In the field of clean energy, hydrogen energy has been highly valued by scholars due to its zero carbon emission and high energy density. At present, hydrogen can be divided into "gray hydrogen", "blue hydrogen" and "green hydrogen" according to carbon emissions. The "gray hydrogen" has low energy conversion efficiency and high carbon emissions, and low environmental benefits. The "blue hydrogen" uses carbon capture devices to reduce carbon emissions and improve efficiency, but still has carbon emissions. The "green hydrogen" is completely free of carbon emissions, greatly reducing carbon management costs, and electrolysis of water is the only "green hydrogen" production technology. However, the proportion of hydrogen produced by electrolysis of water is less than 1% of the total value of hydrogen production. The reason is that the oxygen evolution reaction (OER) reaction kinetics is slow, which limits the overall efficiency of electrolytic water hydrogen production. On the other hand, the scarcity of global freshwater resources has seriously hindered the development and popularization of electrolytic water technology. Therefore, efficient seawater electrolysis hydrogen production technology will open up a new track for the development of water decomposition hydrogen production technology.

[0003] Compared with electrolysis of fresh water, the chlorine ions rich in seawater will undergo chlorine evolution reaction (ClER) at the anode and compete with OER, reducing reaction efficiency, while the product will corrode the catalyst and metal current collector. This phenomenon leads to poor catalytic stability, low OER activity, and high proportion of side reaction ClER in the current direct seawater electrolysis hydrogen production system. Moreover, the mechanical stability of the existing catalytic electrode under industrial-level large current density (> 250 mA / cm 2 ) working conditions is poor, and the catalyst layer is prone to peeling off and separating from the current collector, which is not conducive to the stability of the electrode structure during operation. There are problems such as low hydrogen production efficiency, high energy consumption, and poor running stability. Although some scholars have proposed a technical route of desalinating seawater before electrolysis, the introduction of seawater electrolysis equipment will be detrimental to the complexity, portability and economy of the entire electrolysis system. Moreover, most of the existing catalytic electrodes use high-energy-consuming, difficult-to-operate, long-waiting-time, and equipment-dependent synthesis methods such as hydrothermal and high-temperature calcination. Such methods often increase the cost of practical application, limit the scope of practical application, and make it difficult to produce under real industrial conditions, making it even more difficult to meet the distributed application requirements of special conditions such as ocean-going ships. Therefore, developing efficient, stable and inexpensive direct seawater electrolysis anode catalysts, improving anode OER activity and selectivity, reducing the damage of chloride ions to the electrolysis system, and enhancing the stability of the direct seawater electrolysis hydrogen production system are the key to large-scale production of green hydrogen and an important cornerstone for the industrialization development of seawater hydrogen production.

[0004] Current research has confirmed that transition metal-based catalysts have great application potential in direct electrolysis of seawater OER. However, the catalytic activity and stability of these transition metal-based catalysts still cannot meet the requirements of seawater electrolysis for hydrogen production under industrial conditions, and the electrode composition and structure need to be further designed and optimized. Related studies have shown that optimizing the solid-solid interface between the catalyst layer and the current collector in the electrode structure can effectively improve the catalytic performance of the seawater electrolysis anode (such as Chem. Commun. 2021, 57, 10453-10468; Adv. Sci. 2023, 11, 2307455; EcoMat. 2022, 4, e12199, etc.). Therefore, controllably preparing interface-optimized electrodes with obvious multi-layer structure is crucial to further improve the performance of the direct seawater electrolysis hydrogen production system. However, the research on the design of the multi-layer electrode solid-solid interface is not deep enough, and the universal and efficient synthesis method needs to be improved.

[0005] Therefore, the skilled person in the art is committed to developing a very effective seawater direct electrolysis anode. SUMMARY

[0006] In view of the above defects of the prior art, the technical problem to be solved by the present application is to provide a very effective seawater direct electrolysis anode

[0007] To achieve the above-mentioned purpose, the present application provides a preparation method of a catalytic anode with conductive polymer intercalation, comprising the following steps:

[0008] Step 1, growing conductive polymer organic matter on the nickel foam by chemical deposition method to prepare an electrode;

[0009] Step 2, configuring a mixed solution containing a nickel nitrate aqueous solution and an iron nitrate aqueous solution as an electrolyte, transferring it to a three-electrode electrolytic cell, taking the electrode prepared in step 1 as the cathode of the electrolytic cell and a platinum wire electrode as the anode of the electrolytic cell, and performing electrodeposition;

[0010] Step 3, taking out the nickel foam after electrodeposition, washing and removing the surface moisture to obtain a catalytic anode with conductive polymer intercalation.

[0011] In a preferred embodiment of the present application, in step 1, the conductive polymer organic matter is selected from any one of 3-carboxypyrrone, sodium dodecyl sulfate and ethylenediaminetetraacetic acid.

[0012] In a preferred embodiment of the present application, in step 1, the preparation method of the electrode is:

[0013] The conductive polymer organic matter is dissolved in deionized water to form a solution, then the cleaned foam nickel is immersed in the solution without stirring, and is taken out after a period of time, and is washed to remove surface moisture to obtain the electrode.

[0014] Further, the mass-volume ratio (g / mL) of the conductive polymer organic matter to the deionized water is 1:5-100, preferably 1:50.

[0015] In the preferred embodiment of the present application, in step 2, the molar ratio of the nickel nitrate aqueous solution to the ferric nitrate aqueous solution is 1:1, and the volume ratio is 10:1-1:10, preferably 1:1.

[0016] In the preferred embodiment of the present application, in step 2, the electrodeposition is carried out at a potential of -1.5 V vs. RHE, and the electrodeposition includes two electrodepositions, the electrode is taken out after the first electrodeposition for 6 min, and after removing the surface bubbles, the second electrodeposition is carried out for 6 min to form a more uniform catalyst layer.

[0017] In the preferred embodiment of the present application, in step 2, the mixed solution further comprises a chromium nitrate aqueous solution.

[0018] Further, the concentration of the chromium nitrate aqueous solution is the same as that of the nickel nitrate aqueous solution or the ferric nitrate aqueous solution, and the volume ratio of the chromium nitrate aqueous solution to the nickel nitrate aqueous solution or the ferric nitrate aqueous solution is 1-4:2, preferably 1:1.

[0019] The present application also provides a catalytic anode with conductive polymer intercalation prepared by the preparation method.

[0020] The present application also provides the use of the catalytic anode with conductive polymer intercalation in a seawater electrolysis hydrogen production system.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] 1、The present application uses conductive polymer organic matter to participate in interface engineering strategy, constructs a multilayer electrode, can enhance the interaction between the catalyst and the current collector, regulates the electronic environment of the catalyst, improves the OER activity of the electrode; the conductive polymer layer itself has rich negative functional groups, which can electrostatically repel Cl - in seawater, and as a physical isolation layer, prevents seawater corrosion of the current collector, and the two ways work together to prevent ClER, improves the catalytic stability of seawater direct electrolysis (500+ hours), and improves the catalytic activity and reduces the cost of seawater electrolysis hydrogen production (reduces by 37.5%);

[0023] 2、The application introduces a conductive polymer organic layer between the catalyst layer and the current collector, regulates the solid-solid interface binding force inside the multi-layer electrode, the conductive polymer layer has flexibility and rich functional groups, can build chemical bonds with the catalyst layer and the current collector with stronger binding force, compared with the electrode synthesis methods such as deposition, coating and bonding, has stronger solid-solid interface binding force, and greatly improves the mechanical stability under the condition of a large current of 1A / cm 2 ; realizes seawater stable electrolysis under the industrial current density (100+ hours);

[0024] 3、The application realizes the preparation of a catalytic electrode by using the chemical deposition and electrodeposition method, rapidly synthesizes an electrode with a multi-layer structure under room temperature conditions, has short waiting time, simple operation, rapid reaction and mild conditions. The polymerization method of the conductive polymer layer adopts a simple ion-initiated polymerization method, which is rapid, safe and environmentally friendly, and from the catalyst synthesis process to the hydrogen production process, only an electrolytic cell is required. The total catalyst electrode synthesis process takes less than 25 minutes, and no equipment other than the electrolytic cell is used throughout the process. The electrode synthesis process is safe, environmentally friendly, simple to operate, low in cost and good in portability.

[0025] The concept, specific structure and technical effects of the application will be further described below with reference to the accompanying drawings, so as to fully understand the purpose, features and effects of the application. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A scanning electron microscope photo of a NiFe LDH / ppy / NF catalytic anode with a conductive polymer polypyrrole interlayer grown on a foam nickel;

[0027] Figure 2 A magnified photo of a scanning electron microscope photo of a NiFe LDH / ppy / NF catalytic anode with a conductive polymer polypyrrole interlayer grown on a foam nickel and a corresponding element distribution map;

[0028] Figure 3 A transmission electron microscope photo (TEM) and a high-resolution transmission electron microscope photo (HR-TEM) of a NiFe LDH / ppy / NF catalytic anode with a conductive polymer polypyrrole interlayer grown on a foam nickel;

[0029] Figure 4 X-ray diffraction spectra (XRD) of a foam nickel substrate, a NiFe LDH / NF electrode grown on a foam nickel and a NiFe LDH / ppy / NF catalytic anode with a conductive polymer polypyrrole interlayer grown on a foam nickel;

[0030] Figure 5High resolution X-ray photoelectron spectroscopy (XPS) of NiFe LDH / NF electrode grown on nickel foam and NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation grown on nickel foam at Fe 2p and Ni 2p positions; wherein, a is high resolution X-ray photoelectron spectroscopy (XPS) of NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation at Fe 2p position; b is high resolution XPS peak separation diagram of NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation at Ni 2p position;

[0031] Figure 6 High resolution X-ray photoelectron spectroscopy (XPS) of NiFe LDH / NF electrode grown on nickel foam and NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation grown on nickel foam at Fe 2p and Ni 2p positions before and after long time chronopotentiometry test in alkaline seawater; wherein, a is high resolution X-ray photoelectron spectroscopy (XPS) of NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation at Fe 2p position after stability test, b is high resolution XPS peak separation diagram of NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation at Ni 2p position after stability test;

[0032] Figure 7 Polarization curve comparison diagram of (a) nickel foam substrate (NF), NiFe LDH / NF electrode and NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation, (b) oxygen evolution Tafel curve comparison diagram, and (c) long time chronopotentiometry test diagram at high current density in alkaline seawater.

[0033] Figure 8 Bode plot of (a) NiFe LDH / NF electrode and (b) NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation in alkaline seawater. DETAILED DESCRIPTION

[0034] The technical content of the present application will be more clearly and conveniently understood by introducing the preferred embodiments of the present application with reference to the accompanying drawings of the specification. The present application can be embodied in many different forms, and the scope of protection of the present application is not limited to the embodiments mentioned herein.

[0035] The key of the application is to select a suitable conductive polymer organic intercalation, through the interface engineering strategy of conductive polymer participation, to realize the enhancement of the interaction between the catalyst and the metal current collector while not affecting the electrode charge conduction performance. The electrolysis anode preparation method is simple in operation, rapid in reaction, mild in conditions, suitable for the synthesis of multi-layer structure of direct electrolysis seawater electrode, and can efficiently prepare seawater electrolysis anode with high catalytic activity, high stability and strong corrosion resistance.

[0036] The seawater electrolysis catalyst of the application greatly enhances the intrinsic catalytic activity and OER selectivity due to the interaction between the transition metal layered double hydroxide (TM-LDH) and the conductive polymer organic matter, and compared with the corresponding TM-LDH catalyst without conductive polymer organic matter, it shows lower seawater electrolysis overpotential and higher Faraday efficiency, providing reliable basis for efficient, stable and inexpensive large-scale commercial seawater electrolysis hydrogen production.

[0037] The seawater electrolysis catalyst of the application can be used to prepare seawater electrolysis catalytic anode and direct seawater electrolysis hydrogen production system. The seawater electrolysis anode of the application has structural flexibility and richly adjustable organic functional groups, and when the conductive polymer is used as the interface modification, it can effectively enhance the interaction between the catalyst layer and the current collector, thereby optimizing the electrode solid-solid interface, so that it has lower overpotential and Tafel slope, as well as higher chemical stability and mechanical stability in direct electrolysis of seawater. Therefore, the electrolytic seawater organic intercalation catalytic anode of the application can greatly reduce the cost of direct electrolysis of seawater for hydrogen production, and provides an innovative way for the preparation of durable electrodes for special application scenarios such as large current working conditions and seawater electrolysis hydrogen production, which will have important significance for the development of energy and environment fields.

[0038] The following is illustrated by specific examples.

[0039] Example 1 Preparation of NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation 1.1 Preparation of ppy / NF electrode

[0040] Pyrrole (py) monomers were grown on the nickel foam by chemical deposition method, and then the organic monomer polymerization was initiated to prepare a polypyrrole / NF electrode (ppy / NF electrode), and the specific operation is as follows:

[0041] Take a piece of nickel foam (1cmx2cm), then wash it with deionized water and ethanol alternately for three times, each time for 20min of ultrasonic cleaning, and dry it in a 60℃ oven, ready for use.

[0042] A carboxy pyrrole solution was prepared by adding 1 g of 3-carboxy pyrrole (py-COOH) into a beaker, adding x mL of deionized water, and ultrasonic dispersion for 15 min. The mass fraction of the pyrrole solution was changed by adjusting the value of x, and x was in the range of 5 to 100, preferably x = 50. Then, the cleaned foam nickel was immersed in the carboxy pyrrole solution without stirring, taken out after 12 min, and washed several times with deionized water, and surface moisture was removed by infrared lamp irradiation to obtain a py / NF precursor electrode.

[0043] Then, 0.02703 g of ferric chloride hexahydrate was dissolved in 10 mL of deionized water to prepare a 0.1 M ionic initiator (FeCl3 solution). The py / NF precursor electrode was immersed in the initiator for 2 min, taken out, washed several times with deionized water, and surface moisture was removed by infrared lamp irradiation to obtain a ppy / NF electrode.

[0044] 1.2 Preparation of a NiFe LDH / ppy / NF electrode

[0045] A NiFe LDH / ppy / NF electrode with conductive polymer polypyrrole intercalation was prepared by electrodeposition, and the specific operation was as follows:

[0046] In a beaker, x mL of 5 mM aqueous nickel nitrate (Ni(NO3)2) and y mL of 5 mM aqueous ferric nitrate (Fe(NO3)3) were added, and the Ni / Fe molar ratio in the product was adjusted by adjusting the ratio of x to y, wherein the ratio of x to y was in the range of 10:1 to 1:10, preferably x:y = 1:1. Then, the obtained mixed solution was transferred to a three-electrode electrolytic cell, and the ppy / NF prepared in step 1.1 was taken as the cathode of the electrolytic cell, a platinum wire electrode was taken as the anode of the electrolytic cell, and the above nitrate mixed solution was taken as the electrolyte. The electrodeposition was carried out at a potential of -1.5 V vs. RHE for 12 min. In particular, the electrode was taken out after 6 min of electrodeposition, and after removing the surface bubbles, the electrodeposition was carried out again for 6 min to form a more uniform catalyst layer. After the reaction, the foam nickel was taken out, washed several times with deionized water, and surface moisture was removed by infrared lamp irradiation to obtain a NiFe LDH / ppy / NF electrode, wherein the NiFe LDH nanosheet was a Ni(II) / Fe(III) transition metal layered double hydroxide.

[0047] The NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation prepared in Example 1 was scanned by an electron microscope, and the results are shown in Figure 1 Figure 1 ​It can be seen that the conductive polymer polypyrrole-intercalated NiFe LDH / ppy / NF catalytic anode is still a nanosheet structure, indicating that the conductive polymer organic intercalated catalytic anode prepared by simple chemical deposition and electrodeposition methods does not affect the microstructure of the NiFe LDH catalyst layer.

[0048] Electron microscopy scanning magnification and elemental analysis were performed on the NiFe LDH / ppy / NF catalytic anode with conductive polypyrrole intercalation prepared in Example 1. The results are as follows: Figure 2 As shown. By Figure 2 It can be seen that the elemental distribution of the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation is uniform on the nickel foam.

[0049] The NiFe LDH / ppy / NF catalytic anode with conductive polypyrrole intercalation prepared in Example 1 was subjected to transmission electron microscopy and high-resolution transmission electron microscopy scanning. The results are as follows: Figure 3 As shown. By Figure 3 It is known that the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation grown on nickel foam has the structural characteristics of ultrathin nanostructure and coexistence of crystalline and amorphous structures.

[0050] X-ray diffraction was performed on the nickel foam substrate, the NiFe LDH / NF electrode grown on the nickel foam, and the NiFe LDH / ppy / NF catalytic anode with conductive polypyrrole intercalation prepared in Example 1. The results are as follows: Figure 4 As shown. By Figure 4 It can be seen that ppy intercalation (polypyrrole intercalation) does not affect the crystal form of the catalyst.

[0051] High-resolution X-ray photoelectron spectroscopy (XPS) scans were performed on the NiFe LDH / NF electrode grown on nickel foam and the NiFe LDH / ppy / NF catalytic anode with conductive polypyrrole intercalation grown on nickel foam at the Fe 2p and Ni 2p positions. The results are as follows: Figure 5 As shown. By Figure 5 It is known that the Ni element in the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation has a higher chemical valence state.

[0052] High-resolution X-ray photoelectron spectroscopy (XPS) scans were performed on the Fe 2p and Ni 2p positions of the NiFe LDH / NF electrode grown on nickel foam and the NiFe LDH / ppy / NF catalytic anode with conductive polypyrrole intercalation grown on nickel foam before and after long-term chronopotential testing in alkaline seawater. The results are as follows: Figure 6 As shown. ByFigure 6 It can be seen that the chemical valence of Ni element in the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalated after stability test is obviously increased, while the valence of Fe element is almost unchanged.

[0053] Preparation of NiFeCr LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalated in Example 2

[0054] 2.1 Preparation of NiFeCr LDH / NF electrode

[0055] The NiFeCr LDH / NF electrode was synthesized by electrodeposition method, and the specific operation was as follows.

[0056] In a beaker, 50 mL of 5 mM aqueous nickel nitrate (Ni(NO3)2), 50 mL of 5 mM aqueous ferric nitrate (Fe(NO3)3) and x mL of 5 mM aqueous chromium nitrate (Cr(NO3)3) were added, and the molar ratio of the three transition metals was changed by adjusting the value of x, wherein x was between 25 and 100, preferably x = 50. Then the obtained mixed solution was transferred to a three-electrode electrolytic cell, and the cleaned foam nickel in step 1.1 was taken as the cathode of the electrolytic cell, the platinum wire electrode was taken as the anode of the electrolytic cell, and the above nitrate mixed solution was taken as the electrolyte. The electrodeposition was carried out at a potential of -1.5 V vs. RHE for 12 min. In particular, after 6 min of electrodeposition, the electrode was taken out, the surface bubbles were removed, and then 6 min of electrodeposition was carried out again to form a more uniform catalyst layer. After the reaction, the foam nickel was taken out and washed several times with deionized water, and the surface moisture was removed by infrared lamp irradiation to obtain the NiFeCr LDH / NF electrode, wherein the NiFeCr LDH nanosheet is a Ni(II) / Fe(III) / Cr(III) transition metal layered double hydroxide compound.

[0057] 2.2 Preparation of NiFeCr LDH / ppy / NF electrode

[0058] The NiFeCr LDH / ppy / NF electrode was synthesized by electrodeposition method and chemical deposition method, and the specific operation was as follows.

[0059] In a beaker, 50 mL of 5 mM aqueous nickel nitrate (Ni(NO3)2) solution, 50 mL of 5 mM aqueous iron nitrate (Fe(NO3)3) solution and x mL of 5 mM aqueous chromium nitrate (Cr(NO3)3) solution were added, and the molar ratio of the three transition metals was changed by adjusting the value of x, wherein x was between 25 and 100, preferably x = 50. Then the resulting mixed solution was transferred to a three-electrode electrolysis cell, and the ppy / NF prepared in step 1.1 was taken as the cathode of the electrolysis cell, the platinum wire electrode was taken as the anode of the electrolysis cell, and the above nitrate mixed solution was taken as the electrolyte. The electrodeposition was carried out at a potential of -1.5 V vs. RHE for 12 min. In particular, after 6 min of electrodeposition, the electrode was taken out, the surface bubbles were removed, and then the electrodeposition was carried out again for 6 min to form a more uniform catalyst layer. After the reaction, the nickel foam was taken out and washed several times with deionized water, and then the surface moisture was removed by infrared lamp irradiation to obtain a NiFeCr LDH / ppy / NF electrode, wherein the NiFeCr LDH nanosheet was a Ni(II) / Fe(III) / Cr(III) transition metal layered double hydroxide compound.

[0060] Preparation of a NiFe LDH / SDS / NF catalytic anode with conductive polymer sodium dodecyl sulfate intercalation

[0061] 3.1 Preparation of SDS / NF electrode

[0062] Sodium dodecyl sulfate (SDS) was grown on the nickel foam by chemical deposition method to prepare the SDS / NF electrode, and the specific operation was as follows:

[0063] In a beaker, 1 g of SDS powder was added, and x mL of deionized water was added. After ultrasonic dispersion for 15 min, an SDS solution was prepared. The mass fraction of the SDS solution was changed by adjusting the value of x, wherein x was between 5 and 100, preferably x = 50. Then the cleaned nickel foam prepared in step 1.1 was immersed in the SDS solution without stirring, and after 12 min, it was taken out and washed several times with deionized water, and then the surface moisture was removed by infrared lamp irradiation to obtain the SDS / NF electrode.

[0064] 3.2 Preparation of NiFe LDH / SDS / NF electrode

[0065] The NiFe LDH / SDS / NF electrode with conductive polymer sodium dodecyl sulfate intercalation was prepared by electrodeposition method, and the specific operation was as follows:

[0066] In a beaker, x mL of 5 mM aqueous nickel nitrate (Ni(NO3)2) solution and y mL of 5 mM aqueous ferric nitrate (Fe(NO3)3) solution were added, and the molar ratio of Ni / Fe in the product was adjusted by adjusting the ratio of x to y, wherein the ratio of x to y was between 10:1 and 1:10, preferably x:y = 1:1. Then the resulting mixed solution was transferred to a three-electrode electrolytic cell, and the SDS / NF prepared in step 3.1 was taken as the cathode of the electrolytic cell, the platinum wire electrode was taken as the anode of the electrolytic cell, and the above nitrate mixed solution was taken as the electrolyte. The electrodeposition was carried out at a potential of -1.5 V vs. RHE for 12 min. In particular, after 6 min of electrodeposition, the electrode was taken out, the surface bubbles were removed, and then the electrodeposition was carried out again for 6 min to form a more uniform catalyst layer. After the reaction, the nickel foam was taken out and washed several times with deionized water, and the surface moisture was removed by infrared lamp irradiation to obtain a NiFe LDH / SDS / NF electrode, wherein the NiFe LDH nanosheet is a Ni(II) / Fe(III) transition metal layered double hydroxide.

[0067] Preparation of NiFe LDH / EDTA / NF catalytic anode with conductive polymer ethylenediaminetetraacetic acid intercalation

[0068] 4.1 Preparation of EDTA / NF electrode

[0069] EDTA / NF electrode was prepared by growing ethylenediaminetetraacetic acid (EDTA) on nickel foam by chemical deposition method, and the specific operation was as follows:

[0070] In a beaker, 1 g of EDTA powder was added, x mL of 1 M NaOH was added, and magnetic stirring was carried out at a constant temperature of 40°C for 20 min to prepare an EDTA alkaline solution. The mass fraction of the EDTA alkaline solution was changed by adjusting the value of x, and the value of x was in the range of 5 to 100, preferably x = 50. Then the clean nickel foam prepared in step 1.1 was immersed in the EDTA alkaline solution without stirring, and after 12 min, it was taken out and washed several times with deionized water, and the surface moisture was removed by infrared lamp irradiation to obtain an EDTA / NF electrode.

[0071] 4.2 Preparation of NiFe LDH / EDTA / NF electrode

[0072] NiFe LDH / SDS / NF electrode with conductive polymer sodium dodecyl sulfate intercalation was prepared by electrodeposition method, and the specific operation was as follows:

[0073] In a beaker, x mL of 5 mM aqueous nickel nitrate (Ni(NO3)2) solution and y mL of 5 mM aqueous ferric nitrate (Fe(NO3)3) solution were added, and the molar ratio of Ni / Fe in the product was adjusted by adjusting the ratio of x to y, wherein the ratio of x to y was between 10:1 and 1:10, preferably x:y = 1:1. Then the resulting mixed solution was transferred to a three-electrode electrolytic cell, and the EDTA / NF prepared in step 4.1 was taken as the cathode of the electrolytic cell, the platinum wire electrode was taken as the anode of the electrolytic cell, and the above nitrate mixed solution was taken as the electrolyte. The electrodeposition was carried out at a potential of -1.5 V vs. RHE for 12 min. In particular, after 6 min of electrodeposition, the electrode was taken out, the surface bubbles were removed, and then the electrodeposition was carried out again for 6 min to form a more uniform catalyst layer. After the reaction, the nickel foam was taken out and washed with deionized water several times, and the surface moisture was removed by infrared lamp irradiation to obtain a NiFe LDH / EDTA / NF electrode, wherein the NiFe LDH nanosheet is a Ni(II) / Fe(III) transition metal layered double hydroxide.

[0074] Test of alkaline seawater electrolysis catalytic performance of the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation prepared in Example 1

[0075] The NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation prepared in Example 1 was used as the water decomposition working electrode (working electrode), a platinum wire was used as the counter electrode, Ag / AgCl was used as the reference electrode, and a 1M potassium hydroxide aqueous solution mixed with 0.5M sodium chloride was used as the alkaline simulated seawater electrolyte to construct a seawater electrolysis three-electrode system. Moreover, the NiFe LDH / NF electrode prepared in Example 1 was used as the working electrode, and the seawater electrolysis three-electrode system was constructed in the same way. In addition, the nickel foam substrate was used as the working electrode, and the seawater electrolysis three-electrode system was constructed in the same way. The above three seawater electrolysis three-electrode systems were tested on a CHI 760e electrochemical workstation (Shanghai Chenhua) to verify the seawater electrolysis catalytic performance of the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation of the present application. At the same time, the stability of the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation was tested by chronopotentiometry. The results are shown in Figure 7

[0076] Figure 7 ​(a) shows the comparison of catalytic OER polarization curves of the foam nickel current collector, NiFe LDH / NF electrode and NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation. It can be seen that the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation has the lowest overpotential, indicating that the lowest energy is consumed to achieve the same current density.

[0077] Figure 7 (b) shows the comparison of oxygen evolution Tafel curves of the foam nickel current collector, NiFe LDH / NF electrode and NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation. It can be seen that the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation has the lowest Tafel slope, representing the best reaction kinetics.

[0078] Figure 7 (c) is a graph showing the long-term chronopotentiometric test of the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation at current densities of 25 and 50 mA cm -2 , and the inset is the current density change step curve of the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation within 30 min. It can be seen that the NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation has good seawater electrolysis stability.

[0079] In addition, Figure 8 are the Bode plots of (a) NiFe LDH / NF electrode and (b) NiFe LDH / ppy / NF catalytic anode with conductive polymer polypyrrole intercalation at different potentials, indicating that after adding the conductive polymer polypyrrole intercalation, the charge transfer impedance and the starting potential of OER are significantly reduced, and there is interaction between the conductive polymer layer and the catalyst layer and the current collector.

[0080] In summary, the electrolysis seawater organic intercalation catalytic anode of the application greatly enhances the intrinsic catalytic activity and OER selectivity due to the interaction between TM-LDH and conductive polymer organic matter, and shows lower seawater electrolysis overpotential and higher Faraday efficiency compared with the corresponding TM-LDH catalyst without conductive polymer organic matter; when the organic matter with structural flexibility and rich adjustable functional groups is used as the conductive polymer for interface modification, it can effectively enhance the interaction between the catalyst layer and the current collector, thereby optimizing the electrode solid-solid interface, so it has lower overpotential and Tafel slope, and higher chemical stability and mechanical stability when directly electrolyzing seawater. This application can greatly reduce the cost of direct seawater electrolysis for hydrogen production, and provides an innovative way for the preparation of durable electrodes for special application scenarios such as large current working conditions and seawater electrolysis for hydrogen production.

[0081] The preferred embodiments of the application are described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and changes without creative labor based on the concept of the application. Therefore, any technical solutions obtained by logical analysis, reasoning or limited experiments based on the prior art within the concept of the application should be within the protection scope determined by the claims.

Claims

1. A method for producing a catalytic anode having an electrically conductive polymer intercalation, characterized by, The method comprises the following steps: Step 1, preparing an electrode by growing conductive polymer organic matter on a nickel foam through a chemical deposition method; Step 2, configuring a mixed solution containing a nickel nitrate aqueous solution and an iron nitrate aqueous solution as an electrolyte, transferring the mixed solution to a three-electrode electrolytic cell, taking the electrode prepared in step 1 as a cathode of the electrolytic cell, and taking a platinum wire electrode as an anode of the electrolytic cell to perform electrodeposition; Step 3, taking out the nickel foam after electrodeposition, washing, and removing surface moisture to obtain a catalytic anode with conductive polymer intercalation; In step 2, the electrodeposition is performed at a potential of -1.5 V vs. RHE, and the electrodeposition comprises two times of electrodeposition, the electrode is taken out after the first electrodeposition for 6 min, and after removing surface bubbles, the electrodeposition is performed again for 6 min to form a more uniform catalyst layer.

2. The method for producing a catalytic anode having an electrically conductive polymer intercalated according to claim 1, characterized by, In step 1, the conductive polymer organic matter monomer is selected from 3-carboxyl pyrrole.

3. The method of claim 1, wherein the method is characterized by: In step 1, the preparation method of the electrode is as follows: The conductive polymer organic matter monomer is dissolved in deionized water to form a solution, then the washed and dried nickel foam is immersed in the solution without stirring, is taken out after a period of time, is washed to remove surface moisture, and a precursor electrode is obtained, the precursor electrode is immersed in an initiator, is taken out after a period of time, is washed to remove surface moisture, and the electrode is obtained.

4. The method for producing a catalytic anode having an electrically conductive polymer intercalated according to claim 3, characterized by, The mass-to-volume ratio (g / mL) of the conductive polymer organic matter monomer to the deionized water is 1:5-100.

5. The method of claim 1, wherein the catalytic anode with conducting polymer intercalation is prepared by the steps of: In step 2, the molar ratio of the nickel nitrate aqueous solution to the iron nitrate aqueous solution is 1:1, and the volume ratio is 10:1-1:

10.

6. The method of claim 1, wherein the catalytic anode with conducting polymer intercalation is prepared by the steps of: In step 2, the mixed solution further comprises a chromium nitrate aqueous solution.

7. The method of claim 6, wherein the method further comprises the step of: The concentration of the chromium nitrate aqueous solution is the same as that of the nickel nitrate aqueous solution or the iron nitrate aqueous solution, and the volume ratio of the chromium nitrate aqueous solution to the nickel nitrate aqueous solution or the iron nitrate aqueous solution is 1-4:

2.

8. The catalytic anode with conductive polymer intercalation prepared by the preparation method in any one of claims 1-7.

9. Application of the catalytic anode with conductive polymer intercalation in claim 8 in an electrolytic seawater hydrogen production system.

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