Preparation method and application of anti-reverse current self-supporting electrode for anion exchange membrane water electrolysis hydrogen production

Abstract

The invention relates to a preparation method and application of an electrode, in particular to a preparation method and application of an anti-reverse current self-supporting electrode for anion exchange membrane water electrolysis hydrogen production. The self-supporting (NiCoFe) 9S8 electrode is constructed by adopting a directional solid-phase synthesis strategy to overcome the challenge of performance degradation of the electrolytic cell. The preparation method comprises the following steps: firstly, depositing a precursor solution of FeS2 and CoCl2 on a nickel felt substrate, and then carrying out annealing treatment to obtain uniformly grown (NiCoFe) 9S8; the method not only ensures uniform distribution of multiple metal components, but also constructs firm chemical bonding and efficient charge transfer between the catalyst layer and the conductive substrate through solid-phase interface reaction, and effectively avoids interface impedance caused by introduction of an additional binder. Therefore, high-current-density water electrolysis hydrogen production under intermittent fluctuation power supply is realized. In 1M KOH, the cell voltage is almost not attenuated when the electrode stably operates for 2000h at 500mAcm <-2 >.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for preparing and using an electrode. BACKGROUND

[0002] Hydrogen energy, as a clean, efficient, and sustainable secondary energy source, can be obtained through various paths and is an important carrier for building a clean and low-carbon energy structure in the future. Currently, although hydrogen production from fossil fuels has low cost, it has high carbon emissions, with more than 16 kg of CO2 emitted per kg of hydrogen produced from coal. Water electrolysis hydrogen production technology uses H2 as an energy storage medium, can produce hydrogen on a grid scale, and realizes efficient consumption of intermittent excess renewable energy. The carbon emission level is extremely low, and it is expected to achieve a technological breakthrough in the short term. Currently, water electrolysis hydrogen production processes mainly include alkaline water electrolysis (AWE), proton exchange membrane water electrolysis (PEMWE), solid polymer anion exchange membrane water electrolysis (AEMWE), and solid oxide water electrolysis (SOEWE) technical routes. Among them, AWE is the earliest industrialized water electrolysis technology, with decades of application experience, and is the most mature. PEMWE technology has compact structural characteristics and fast kinetic response, and can more efficiently meet the rapid storage demand of intermittent energy, thereby reducing the comprehensive cost of green hydrogen production. At present, this technology has basically taken shape, and has initially realized the commercialization of technology. However, its high equipment cost, dependence on noble metal catalyst materials, and insufficient research and accumulation in the field of core materials such as proton exchange membranes in China still restrict the large-scale promotion of this technology in the domestic market.

[0003]

[0004] Among various hydrogen production technology paths, water electrolysis driven by renewable energy is a sustainable and environmentally friendly "green hydrogen" production method. Among them, AEMWE, as a new generation of water electrolysis technology, has received more and more attention in recent years. AEMWE not only integrates the advantages of PEMWE in high current density output, fast dynamic response, and system compact integration, but also allows the use of non-noble metal catalysts (such as Ni, Fe, and Co-based materials) and low-cost porous electrodes and polymer membrane materials under alkaline operating conditions compared to traditional AWE, thereby significantly reducing the overall system cost. In terms of performance and economy, AEMWE shows good application prospects and is widely considered as an important development direction for the next generation of green hydrogen production technology.

[0005] Despite the significant progress in catalyst development and electrolyzer configuration in recent years, the operational stability of AEMWE under real renewable energy coupling conditions still faces major challenges. Unlike the steady-state operation mode under stable power supply of the power grid, AEMWE systems driven by renewable energy often face complex dynamic conditions such as large current fluctuations, frequent start-stop and unpredictable load mutations. Under fluctuating conditions, transient changes in current and voltage can trigger a series of adverse electrochemical and structural effects. Instantaneous high current or high potential can not only cause local overheating and abnormal local potential rise, but also accelerate the structural collapse of the catalyst and the dissolution of active substances, leading to the shedding of the catalyst layer. In particular, sudden increases in current can generate a large number of bubbles on the electrode surface, which can easily block active sites, worsen interfacial mass transfer behavior, and further exacerbate the accumulation of interfacial stress. In the process of repeated reduction and re-oxidation and dissolution and re-deposition, the interfacial stress and material migration work together to cause local structural collapse and induce the formation of a dense inert covering layer, hindering electrolyte penetration and reactant diffusion. The above multiple factors work together to significantly reduce electrode activity and stability and accelerate the performance degradation of the electrolyzer. SUMMARY

[0006] To solve the above technical problems, the present application provides a preparation method of a self-supporting electrode for anion exchange membrane water electrolysis for hydrogen production and its application in water electrolysis for hydrogen production.

[0007] The present application uses a directional solid-phase synthesis strategy to construct a self-supporting (NiCoFe)9S8 electrode to overcome the above challenges. First, by depositing a precursor solution of FeS2 and CoCl2 on a nickel felt substrate, followed by annealing treatment, a uniformly grown (NiCoFe)9S8 is obtained; this method not only ensures the uniform distribution of multi-metal components, but also constructs a firm chemical bond and efficient charge transfer between the catalyst layer and the conductive substrate through solid-phase interfacial reaction, effectively avoiding the interfacial impedance caused by the introduction of additional adhesives, thereby realizing large current density water electrolysis for hydrogen production under intermittent fluctuating power supply.

[0008] A preparation method of a self-supporting electrode for anion exchange membrane water electrolysis for hydrogen production, specifically completed by the following steps:

[0009] I. The nickel felt is cleaned to remove the surface oxide layer, and a pretreated nickel felt is obtained;

[0010] II. The FeS2 powder is ground into fine powder in a mortar, and then the FeS2 fine powder and CoCl2·6H2O are dispersed in anhydrous ethanol, and ultrasonic dispersion is performed to obtain a uniformly dispersed precursor solution;

[0011] III. The precursor solution is added dropwise to the pretreated nickel felt, and then placed in a vacuum drying oven for vacuum drying to obtain a dried sample;

[0012] Four, the dried sample is placed in a tube furnace, and high temperature annealing treatment is carried out under a nitrogen atmosphere, to obtain a conductive (NiCoFe) 9S8 electrode;

[0013] Five, the conductive (NiCoFe) 9S8 electrode is placed in a KOH electrolyte, and the conductive (NiCoFe) 9S8 electrode is treated under a constant current, to obtain a self-supporting electrode for resisting reverse current in an anion exchange membrane water electrolysis hydrogen production.

[0014] The self-supporting electrode for resisting reverse current in an anion exchange membrane water electrolysis hydrogen production is used for water electrolysis hydrogen production.

[0015] Advantages of the present application:

[0016] One, the present application prepares a self-supporting electrode for resisting reverse current in an anion exchange membrane water electrolysis hydrogen production by directional solid-phase synthesis combined with an electrochemical activation strategy, that is, a self-supporting electrode with an amorphous CoFeOOH shell / conductive (NiCoFe) 9S8 core, which has abundant active sites and excellent electron transport capacity; under a reverse current (RC) condition, the structure can significantly weaken the reverse current peak value and potential transient, and inhibit the rapid reduction and dissolution of active substances; in 1 M KOH, the electrode has a current density of 500 mA cm -2 , and a voltage decay rate of 0.03 mV h -1 under 10 min intermittent cycle start-stop operation for 1100 h, which is better than most reported advanced non-noble metal OER electrodes, and fully reflects its RC corrosion resistance and long-term durability under stable and fluctuating operating conditions;

[0017] Two, the assembled AEMWE system can be stably operated for more than 13000 cycles (1750 h) under the accelerated stress test condition of RC (2-1.5-1-0.5-0-0.5-1-1.5 A cm -2 , cycle 8 min), and only 2.08 V is required to drive a current density of 500 mA cm -2 , and the energy efficiency is as high as 60%, the energy consumption is reduced by about 30% compared with the commercial NiFe anode system, and the hydrogen production cost is as low as 1.11 dollars / GGE. Further, large-size monolithic electrodes are prepared and successfully applied to solid polymer anion exchange membrane water electrolysis (AEMWE) devices, which can adapt to mainstream AEM electrolytic cell models, and are expected to be popularized and demonstrated in green hydrogen production scenarios. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1Figure 1 is a schematic diagram of the synthesis process and characterization of a self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production in Example 1, where (a) is a schematic diagram of the synthesis process, (b) is an XRD pattern of the conductive (NiCoFe)9S8 electrode and the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production, (c) is a SEM image of the conductive (NiCoFe)9S8 electrode, and (d) is a SEM image of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production.

[0019] Figure 2 Figure 2 is a characterization of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production prepared in Example 1, where (a) is a TEM image, (b) is a HRTEM image, and (c-g) are EDS results.

[0020] Figure 3 Figure 3 is the electrochemical behavior of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production prepared in Example 1 in a three- electrode system during the reverse current process, where (a) is a reverse potential change curve of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production under stable start-stop cycle conditions (1 A cm-2, 5 min start / stop) for 2 h, (b) is a schematic diagram of the active material conversion path that the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production can undergo during frequent start-stop processes, (c) is a comparison of the potential response of the commercial NiFe anode and the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production at different current densities, and (d) is an RC comparison of the commercial NiFe anode and the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production. -2

[0021] Figure 4 Figure 4 is the OER performance of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production prepared in Example 1, where (a) is an LSV curve of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production, NiFe, RuO2, NiCoFeS, and Ni felt electrodes in 1 M KOH solution, (b) is a comparison of the overpotential of different electrodes, (c) is a Tafel curve of different electrodes, (d) is a comparison of the current density at an overpotential of 300 mV, (e) is a double-layer capacitance (Cdl) analysis of different electrodes, and (f) is a comparison of the electrochemically active surface area (ECSA) of different electrodes.

[0022] Figure 5 Figure 5 is the stability of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production prepared in Example 1 under constant voltage and start-stop intermittent electrolysis conditions, where (a) is a comparison of the current density of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production in 1 M KOH, 500 mA cm-2, and (b) is a comparison of the current density of the self- supported electrode for use in anion exchange membrane water electrolysis for hydrogen production in 1 M KOH, 1000 mA cm-2.​-2 (a) Voltage curves obtained after 2000h constant current testing (with iR correction); (b) Comparison of OER performance between the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production and other recently reported advanced electrode materials; (c) Voltage curves obtained by anion exchange membrane water electrolysis for hydrogen production under 1M KOH and 500mA / cm² conditions. -2 (d) shows the stability test of the start-stop cycle (10 min start-stop cycle); (d) is the decay rate of the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production and other recent advanced electrode materials (D). v (Comparison); all experiments were conducted at room temperature;

[0023] Figure 6 The electron transport and stabilization interface structure characterization of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane electrolysis of water; (a) shows the resistivity of the self-supporting electrode against reverse current and the commercial NiFe electrode for hydrogen production by anion exchange membrane electrolysis of water; (b) shows the conductivity of the self-supporting electrode against reverse current and the powdered Ni-CoFeOOH electrode for hydrogen production by anion exchange membrane electrolysis of water; (c) shows micro-scratches and friction-normal force curves of the commercial NiFe and (d) self-supporting electrodes against reverse current in anion exchange membrane electrolysis of water.

[0024] Figure 7 The rapid bubble desorption kinetics of the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production prepared in Example 1; (a) shows the contact angle changes of water droplets on NiFe and the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production prepared in Example 1 at 0s, 30s and 60s; (b) shows the adhesion curve and corresponding snapshot image of the bubble detaching from the electrode at the instant.

[0025] Figure 8 In-situ spectroscopic characterization of the anti-RC stability mechanism; Figure (a) shows the in-situ Raman spectra of the NiFe electrode at different potentials in 1M KOH; (b) shows the in-situ Raman spectra of the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production at different potentials in 1M KOH; (c) shows the in-situ Raman spectra of the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production under high current density start-stop intermittent electrolysis conditions in 1M KOH.

[0026] Figure 9In-situ spectroelectrochemical characterization of the anti-RC reaction pathway; (a) In-situ ATR-SEIRAS spectra of the anti-RC self-supporting electrode in 1 M KOH at different potentials for water electrolysis to hydrogen in anion exchange membrane (AEM) ; (b) Time-dependent in-situ ATR-SEIRAS measurement of the anti-RC self-supporting electrode in 1 M KOH at a fixed potential of 1.7 V vs RHE for water electrolysis to hydrogen in anion exchange membrane (AEM) ;

[0027] Figure 10 Performance and stability of AEMWE driven by fluctuating power; (a) AEMWE cell voltage curve for continuous operation of 1750 h at a large fluctuating current density based on a reverse current accelerated stress test protocol; (b) Comparison of AEMWE electrolysis energy consumption and efficiency using NiFe and NiPt as anode and cathode, respectively, for the anti-RC self-supporting electrode in water electrolysis to hydrogen in anion exchange membrane (AEM) ; (c) Estimated cost of AEMWE to produce 1.0 kg of hydrogen under the condition of 500 mA cm -2 under the condition of 500 mA cm DETAILED DESCRIPTION

[0028] DETAILED DESCRIPTION

[0029] I. The nickel felt is cleaned to remove the surface oxide layer to obtain pretreated nickel felt;

[0030] II. The FeS2 powder is ground into fine powder in a mortar, and then the FeS2 fine powder and CoCl2·6H2O are dispersed in anhydrous ethanol, and ultrasonic dispersion is performed to obtain a uniformly dispersed precursor solution;

[0031] III. The precursor solution is added dropwise to the pretreated nickel felt, and then placed in a vacuum drying oven for vacuum drying to obtain a dried sample;

[0032] IV. The dried sample is placed in a tube furnace, and then high-temperature annealing treatment is performed under a nitrogen atmosphere to obtain a conductive (NiCoFe)9S8 electrode;

[0033] V. The conductive (NiCoFe)9S8 electrode is placed in a KOH electrolyte, and the conductive (NiCoFe)9S8 electrode is treated under a constant current to obtain an anti-RC self-supporting electrode for water electrolysis to hydrogen in anion exchange membrane (AEM).

[0034] Specific embodiment two: the difference between this embodiment and specific embodiment one is that: in step one, the nickel felt is cleaned by using acetone, hydrochloric acid, anhydrous ethanol and deionized water in sequence to remove the surface oxide layer; the mass fraction of the hydrochloric acid is 37%; in step one, the thickness of the nickel felt is 0.4 mm, and the size is 1 cm x 1.2 cm. The other steps are the same as those in specific embodiment one.

[0035] Specific embodiment three: the difference between this embodiment and one of specific embodiments one or two is that: in step two, the mass of the FeS2 fine powder and the volume of the anhydrous ethanol are (3.36 mg ~ 70 mg) : (48 μL ~ 1000 μL); in step two, the mass of the CoCl2·6H2O and the volume of the anhydrous ethanol are (6.66 mg ~ 138.5 mg) : (48 μL ~ 1000 μL). The other steps are the same as those in specific embodiments one or two.

[0036] Specific embodiment four: the difference between this embodiment and one of specific embodiments one to three is that: in step two, the ultrasonic dispersion time is 30 min ~ 50 min. The other steps are the same as those in specific embodiments one to three.

[0037] Specific embodiment five: the difference between this embodiment and one of specific embodiments one to four is that: in step three, the dropwise addition amount of the precursor solution is 1 mg / cm 2 ~ 5 mg / cm 2 . The other steps are the same as those in specific embodiments one to four.

[0038] Specific embodiment six: the difference between this embodiment and one of specific embodiments one to five is that: in step three, the vacuum drying temperature is 60 ℃ ~ 80 ℃, and the vacuum drying time is 6 h ~ 8 h. The other steps are the same as those in specific embodiments one to five.

[0039] Specific embodiment seven: the difference between this embodiment and one of specific embodiments one to six is that: in step four, the high-temperature annealing temperature is 450 ℃ ~ 850 ℃, and the high-temperature annealing time is 2 h ~ 6 h. The other steps are the same as those in specific embodiments one to six.

[0040] Specific embodiment eight: the difference between this embodiment and one of specific embodiments one to seven is that: in step five, the constant current is 0.5 A cm -2 ~ 2 A cm -2 ; in step five, the concentration of the KOH electrolyte is 1 mol / L ~ 6 mol / L. The other steps are the same as those in specific embodiments one to seven.

[0041] Specific embodiment nine: the difference between this embodiment and one of the specific embodiments one to eight is that in step five, the conductive (NiCoFe) 9S8 electrode is placed in the KOH electrolyte, and the conductive (NiCoFe) 9S8 electrode is treated for 3h~7h under constant current. The other steps are the same as specific embodiments one to eight.

[0042] Specific embodiment ten: this embodiment is the anti-reverse current self-supporting electrode for water electrolysis for anion exchange membrane water electrolysis for hydrogen production.

[0043] The beneficial effects of the present application are verified by the following examples:

[0044] Example 1: a preparation method of an anti-reverse current self-supporting electrode for water electrolysis for hydrogen production by anion exchange membrane water electrolysis, which is completed according to the following steps:

[0045] I. The nickel felt is cleaned to remove the surface oxide layer, and the pretreated nickel felt is obtained;

[0046] In step one, the nickel felt is sequentially cleaned with acetone, hydrochloric acid, anhydrous ethanol and deionized water, each for 1 time, to remove the surface oxide layer; the mass fraction of the hydrochloric acid is 37%;

[0047] In step one, the thickness of the nickel felt is 0.4mm, and the size is 1cm×1.2cm;

[0048] II. The FeS2 powder is ground into fine powder in a mortar, and then the FeS2 fine powder and CoCl2·6H2O are dispersed in anhydrous ethanol, and ultrasonic dispersion is performed for 45min to obtain a uniformly dispersed precursor solution;

[0049] In step two, the mass of the FeS2 fine powder to the volume of the anhydrous ethanol is 3.36mg:48μL;

[0050] In step two, the mass of the CoCl2·6H2O to the volume of the anhydrous ethanol is 6.66mg:48μL;

[0051] III. The precursor solution is added dropwise to the pretreated nickel felt, and then placed in a vacuum drying oven at 80℃ for vacuum drying for 6h to obtain a dried sample;

[0052] In step three, the dropwise amount of the precursor solution is 4mg / cm 2 ;

[0053] IV. The dried sample is placed in a tube furnace, and then high-temperature annealing treatment is performed under a nitrogen atmosphere to obtain a conductive (NiCoFe) 9S8 electrode;

[0054] In step four, the high-temperature annealing temperature is 750℃, and the high-temperature annealing time is 4h.

[0055] 5. Place the conductive (NiCoFe)9S8 electrode in a 1 mol / L KOH electrolyte solution, at a flow rate of 1 A / cm. -2 A conductive (NiCoFe)9S8 electrode was treated under constant current for 5 hours to obtain a self-supporting electrode resistant to reverse current for use in anion exchange membrane water electrolysis to produce hydrogen.

[0056] Characterization of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane water electrolysis:

[0057] Figure 1 The figure shows the synthesis process and characterization diagram of a self-supporting electrode for reverse current resistance in anion exchange membrane electrolysis of water to produce hydrogen in Example 1. (a) is a schematic diagram of the synthesis process, (b) is the XRD pattern of the conductive (NiCoFe)9S8 electrode and the self-supporting electrode for reverse current resistance in anion exchange membrane electrolysis of water to produce hydrogen, (c) is the SEM image of the conductive (NiCoFe)9S8 electrode, and (d) is the SEM image of the self-supporting electrode for reverse current resistance in anion exchange membrane electrolysis of water to produce hydrogen.

[0058] from Figure 1 It can be seen that the conductive (NiCoFe)9S8 electrode prepared in step four of Example 1, after electrochemical activation, eventually forms a catalyst. During this process, the chemical bonding interface remains stable. Figure 1 (a); XRD results ( Figure 1 (b) shows that the prepared material exhibits obvious (NiCoFe)9S8 diffraction peaks (PDF#30-0444), and characteristic peaks of the substrate metal Ni (PDF#04-0850) are also visible, indicating that the initial active material was generated in situ on the nickel felt framework. This is highly consistent with the SEM image of (NiCoFe)9S8 obtained by photography. Figure 1 (c) After electrochemical activation, the diffraction peak intensity decreased significantly and the peak shape broadened, indicating that the crystallinity of the material decreased and most of it was transformed into an amorphous hydroxide structure. Figure 1 (d).

[0059] Combining TEM and high-resolution TEM ( Figure 2 Observations in (a) and (b) show that the activated catalyst forms an amorphous, non-crystalline coating layer on its outer surface, while retaining a small amount of crystalline structure internally, indicating a composite structure of crystalline and amorphous materials. This structure possesses both the abundant unsaturated coordination active sites found in amorphous materials and the excellent intrinsic conductivity and long-term stability of crystalline materials, achieving a balance between high active site exposure and structural stability. Furthermore, energy dispersive spectroscopy (EDS) elemental analysis... Figure 2The results show that S is gradually dissolved from (NiCoFe)9S8 during the electrochemical activation process, and the in-situ dissolution of S helps to relieve the lattice stress, thereby inhibiting the dissolution of active material Fe. At the same time, Ni, Co, and Fe are uniformly distributed in the catalyst, and no obvious composition separation is observed, indicating that the directional solid-phase synthesis strategy can achieve uniform doping of multi-metal elements at the nanoscale. In this process, the surface sulfide is gradually oxidized to Ni-CoFeOOH rich in Ni, Co, and Fe, while the inner core (NiCoFe)9S8 remains as a highly conductive skeleton. This "core / shell" structure not only significantly improves the hydrophilic oxidation ability of the surface active site, but also relies on the conductive sulfide core to provide an excellent electron transport channel, thereby synergistically optimizing the overall electrocatalytic performance.

[0060] Electrochemical behavior analysis of the self-supporting electrode prepared in Example 1 for use in anion exchange membrane electrolysis of water for hydrogen production in reverse current:

[0061] To systematically evaluate the electrochemical behavior of the self-supporting electrode prepared in Example 1 for use in anion exchange membrane electrolysis of water for hydrogen production under RC conditions induced by frequent start / stop cycles, it was studied in a three-electrode system. In a single-cell three-electrode system, Ni-CoFeOOH was used as the working electrode, commercial NiPt as the counter electrode, Hg / HgO (1.0 M NaOH) as the reference electrode, and 1M KOH solution as the electrolyte.

[0062] Figure 3 To evaluate the electrochemical behavior of the self-supporting electrode prepared in Example 1 for use in anion exchange membrane electrolysis of water for hydrogen production in a three-electrode system during the reverse current process, Figure (a) shows the reverse potential change curve of the self-supporting electrode for use in anion exchange membrane electrolysis of water for hydrogen production under stable start / stop cycle conditions (1Acm -2 , 5min start / stop) for 2h; (b) shows a schematic diagram of the active material conversion path that the self-supporting electrode for use in anion exchange membrane electrolysis of water for hydrogen production may undergo during frequent start / stop; (c) shows a comparison of the potential response of the commercial NiFe anode and the self-supporting electrode for use in anion exchange membrane electrolysis of water for hydrogen production under different current densities; (d) shows a comparison of the RC of the commercial NiFe anode and the self-supporting electrode for use in anion exchange membrane electrolysis of water for hydrogen production;

[0063] From Figure 3 it can be seen that when the 5min start / stop cycle experiment is carried out at a current density of 1Acm -2 , the self-supporting electrode for use in anion exchange membrane electrolysis of water for hydrogen production exhibits a highly repeatable reverse potential (1.0V vs. Hg / HgO) for 2h of continuous testing. Figure 3In a). At the moment of shutdown, the potential rapidly dropped to about -0.1 V vs. RHE, indicating that the RC effect induced a reverse polarization. This lower reverse potential mainly drives the reduction of surface metal active species hydroxyl oxide (M-OOH) to form low-valence metal active species hydroxide (M(OH)2), and when the intermittent potential resumes operation, these low-valence active species will be re-oxidized to form a reversible surface structure dynamic reconstruction cycle (M(OH)2→M-OOH) Figure 3 In b). This reversible dynamic reconstruction maintains or even improves the OER performance.

[0064] Further comparison of the response potential of the commercial NiFe anode and the self-supporting electrode for water electrolysis in anion exchange membrane for hydrogen production under different current densities (I) Figure 3 In c), it is found that the self-supporting electrode for water electrolysis in anion exchange membrane for hydrogen production always exhibits a lower anode potential when operated at a constant current. For example, at 1 A cm -2 , the potential of the commercial NiFe anode can be reduced from 1.70 V vs. RHE to 1.45 V vs. RHE, reducing the energy consumption by about 15%. In addition, during the shutdown transient process, the potential of the self-supporting electrode for water electrolysis in anion exchange membrane for hydrogen production drops more gently, indicating that its reverse polarization driving force under RC induction is relatively small. This advantage is also reflected in the reverse current density curve (d) Figure 3 In d), the commercial NiFe anode exhibits a higher instantaneous RC peak (about -20 mA cm -2 @1Acm -2 ) under different current densities, while the RC peak of the self-supporting electrode for water electrolysis in anion exchange membrane for hydrogen production is significantly reduced. This indicates that the reverse transmission rate of interface electrons of the self-supporting electrode for water electrolysis in anion exchange membrane for hydrogen production is inhibited, exhibiting a similar effect of "surface potential passivation layer", thereby effectively resisting reverse potential corrosion. This difference may be due to the presence of amorphous CoFeOOH layer on its surface, which has a high charge buffering capacity. The redox conversion of Co 3+ / Co 2+ provides a wide buffer interval to store or release electrons, thereby stabilizing the potential and delaying the rapid reduction process induced by RC, reducing the risk of active species dissolution.

[0065] Under the RC conditions induced by frequent start / stop cycles, the self-supporting electrode for water electrolysis in anion exchange membrane for hydrogen production exhibits a lower reverse current peak and a more gentle potential transient characteristic, reflecting its excellent anti-RC corrosion and reduction stability. This property helps to inhibit the degradation and loss of active sites of the electrode caused by RC effect, significantly improving the structural stability and durability of the material.

[0066] OER performance of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane water electrolysis:

[0067] The OER electrocatalytic performance advantage of the self-supporting electrode resistant to reverse current in the three-electrode system of 1M KOH solution for hydrogen production via anion exchange membrane water electrolysis was further evaluated. It was found that the CoFeOOH electrode exhibited superior OER activity under the same conditions. In the single-cell three-electrode system, Ni-CoFeOOH was used as the working electrode, commercial NiPt as the counter electrode, and Hg / HgO (1.0 M NaOH) as the reference electrode.

[0068] Figure 4 The OER performance of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane electrolysis of water is shown in the following figures: (a) LSV curves of the self-supporting electrode against reverse current, NiFe, RuO2, NiCoFeS and NiFe1 electrodes in 1M KOH solution; (b) Comparison of overpotentials of different electrodes; (c) Tafel curves of different electrodes; (d) Comparison of current densities at an overpotential of 300mV; (e) Analysis of double layer capacitance (Cdl) of different electrodes; (f) Comparison of electrochemical active surface area (ECSA) of different electrodes.

[0069] from Figure 4 It can be seen from the LSV curve ( Figure 4 As can be seen from a), CoFeOOH at 200 mA / cm² -2 The required overpotential is only 304 mV, significantly lower than that of commercial NiFe (350 mV) and RuO2 (431 mV) electrodes, demonstrating higher catalytic activity. Comparison of overpotentials at different current densities ( Figure 4 (b) and current density analysis under constant overpotential ( Figure 4 (d) indicates that at 100 mAcm -2 At η = 300 mV, the overpotential of the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production is 295 mV, slightly higher than that of NiFe (284 mV). This is mainly attributed to the significant oxidation peak current of Ni in the NiFe electrode. However, at η = 300 mV, the current density of the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production reaches 140% of that of the commercial NiFe electrode. (Tafel curve) Figure 4 As shown in c), the slope of the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production is 36.8 mVdec. -1 It is significantly lower than that of NiFe (114.7 mVdec). -1 ) and RuO2 (168.6 mVdec-1 This indicates that the self-supporting electrode resistant to reverse current, used in anion exchange membrane water electrolysis for hydrogen production, exhibits faster mass transport kinetics. dl test( Figure 4 Results (e) show that the self-supporting electrode resistant to reverse current used in anion exchange membrane water electrolysis for hydrogen production has the highest double-layer capacitance of 6.1 mF / cm. -1 It is superior to other comparative electrodes. Combined with calculations of the electrochemically active surface area (ECSA), it is shown to be superior. Figure 4 (f), its ECSA reached 152.5 cm. 2 It is significantly higher than that of NiFe (112.5 cm⁻¹). 2 ) and RuO2 (105cm 2 The results indicate that the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production exposes more active sites during electrochemical activation, thereby enhancing OER performance. These results collectively demonstrate that the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production possesses low overpotential, high current response, fast kinetics, and abundant active sites, exhibiting excellent OER catalytic potential.

[0070] Based on the above evaluation results of the OER electrocatalytic performance of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production in a three-electrode system in 1M KOH solution, the operational stability and durability of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production were further evaluated under high current density, steady-state, and dynamic start-stop conditions. (See...) Figure 5 As shown;

[0071] Figure 5 The stability of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane electrolysis of water under constant voltage and start-stop intermittent electrolysis conditions; (a) The stability of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane electrolysis of water under 1M KOH and 500mAcm -2 (a) Voltage curves obtained after 2000h constant current testing (with iR correction); (b) Comparison of OER performance between the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production and other recently reported advanced electrode materials; (c) Voltage curves obtained by anion exchange membrane water electrolysis for hydrogen production under 1M KOH and 500mA / cm² conditions. -2 (d) shows the stability test of the start-stop cycle (10 min start-stop cycle); (d) is the decay rate of the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production and other recent advanced electrode materials (D). v (Comparison); all experiments were conducted at room temperature;

[0072] from Figure 5It can be seen that the self-supporting electrode resisting reverse current in anion exchange membrane electrolysis for hydrogen production exhibits excellent stability and durability under high current density conditions. In 1M KOH electrolyte, at 500 mA / cm², -2 After 2000 hours of constant current operation, the tank voltage showed only slight fluctuations and almost no significant attenuation. Figure 5 (a) indicates that it possesses excellent structural and electrochemical stability during long-term constant-load operation. In start-stop intermittent operation (10-minute start-stop cycle), Figure 5 The self-supporting electrode (c) used in anion exchange membrane electrolysis for hydrogen production maintained low overpotential and stable performance output during a 1100-hour operation, verifying its resistance to RC corrosion under fluctuating conditions such as frequent start-stop and intermittent electrolysis. Compared with the most advanced non-precious metal materials currently available... Figure 5 (b) is used in anion exchange membrane electrolysis for hydrogen production, employing a self-supporting electrode resistant to reverse current at 500 mA / cm². -2 The stable operating time is among the best of recent non-precious metal OER electrodes. Furthermore, under three-electrode conditions, a 500mAcm test was conducted. -2 After 1100 hours of intermittent electrolysis with start-stop cycles, its voltage decay rate (D) v Only 0.03mV h -1 It is significantly superior to most reported catalysts. Figure 5 (d) This further highlights its advantages in resisting RC corrosion and long-term operation under fluctuating conditions such as frequent start-stop and intermittent electrolysis. This excellent stability is attributed to the electron transport dynamics and robust interfacial mechanical properties of the self-supporting electrode used in anion exchange membrane water electrolysis for hydrogen production, which effectively alleviates interfacial stress accumulation and structural deactivation, thus maintaining high-efficiency OER performance under both steady-state and dynamic start-stop conditions.

[0073] Example 1: Highly efficient electron transport and stable interface structure for a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production:

[0074] To further evaluate the resistance to RC corrosion and long-term stability of the self-supporting electrode used in anion exchange membrane water electrolysis for hydrogen production under fluctuating power conditions such as frequent start-stop and intermittent electrolysis, the resistivity, conductivity, and interfacial bonding of the electrode were assessed. (See attached data.) Figure 6 As shown.

[0075] Figure 6Characterization of electron transport and stable interface structure of self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen prepared in Example 1; (a) is the resistivity of self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen and commercial NiFe electrode; (b) is the conductivity of self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen and powdered Ni-CoFeOOH electrode; (c) and (d) are microscratch photos and friction force-normal force curves of commercial NiFe and self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen, respectively;

[0076] Figure 6 It is shown that the resistivity of self-supported Ni-CoFeOOH electrode is significantly lower than that of commercial NiFe at 9-15 MPa, which is attributed to the efficient electron channel provided by the highly conductive (NiCoFe)9S8 core, the tight combination of the shell CoFeOOH to reduce the contact resistance, and the in-situ growth on the three-dimensional porous framework to enhance the overall conductivity and mechanical stability, avoiding interface resistance and catalyst layer shedding, and realizing excellent conductivity performance. The conductivity of self-supported and powdered CoFeOOH is further explored (Fig. Figure 6 It is found that the charge transport performance of self-supported Ni-CoFeOOH electrode is always significantly higher than that of powdered electrode in the same pressure range, which reflects the synergistic strengthening effect of the conductive framework and the chemical bonding interface.

[0077] Interface bonding force test (Fig. Figure 6 It is shown that when the self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen is subjected to a critical positive force of 2.71 N, Ni-CoFeOOH will separate from the Ni felt substrate, while the commercial NiFe electrode only needs 1.26 N. The results show that the self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen has stronger interface stability and mechanical integrity compared with the NiFe electrode. This strong bonding interface not only improves the structural stability during long-term operation, but also provides a guarantee for inhibiting catalyst layer peeling under high-frequency start-stop conditions.

[0078] Fast bubble detachment behavior of self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen prepared in Example 1:

[0079] Bubble dynamics test further reveals the excellent bubble detachment performance of self-supported electrode for anion exchange membrane water electrolysis to produce hydrogen, as shown in Fig. Figure 7

[0080] Figure 7 ​(a) is the contact angle change of water droplets on the surface of the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current at 0 s, 30 s and 60 s; (b) is the adhesion force curve and the corresponding snapshot image of the bubble detachment from the electrode instantaneously;

[0081] Figure 7 Fig. a shows the contact angle measurement results at 0 s, 30 s and 60 s, and the contact angle test finds that the surface of the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current is more hydrophilic, which is mainly due to the existence of the surface LDH structure and the hydrophilic group, and the water droplets penetrate more quickly on the Ni-CoFeOOH and are more easily wetted than on the NiFe. Figure 7 Fig. b shows the significant difference in bubble adhesion behavior between the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current and the commercial NiFe electrode. The adhesion force curve and the corresponding snapshot show that the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current has more excellent bubble detachment characteristics, and its bubble adhesion force is only 0.051 mN, which is much lower than that of the NiFe electrode, which is 0.160 mN. Low adhesion force promotes the rapid release of bubbles at high current density, reduces the shielding effect, and improves the utilization rate of catalytic active sites. In contrast, the NiFe electrode has a higher bubble adhesion force, and the bubble grows to a larger size to overcome this adhesion and detach from the electrode surface.

[0082] The durability origin and reaction path of the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current:

[0083] To further understand the internal mechanism of the excellent RC resistance stability of the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current under intermittent electrolysis conditions, the present application combines in-situ Raman and in-situ ATR-SEIRAS spectroscopy systems to reveal the structural evolution and reaction path characteristics. The structural changes of (NiCoFe)9S8 during the electrochemical activation process are analyzed by in-situ Raman, as shown in Figure 8 .

[0084] Figure 8 The in-situ spectroscopy characterization of the RC resistance stability mechanism; Fig. (a) is the in-situ Raman spectrum of the NiFe electrode at different potentials in 1M KOH; (b) is the in-situ Raman spectrum of the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current at different potentials in 1M KOH; (c) is the in-situ Raman spectrum of the self-supporting electrode prepared in Example 1 for use in the anion exchange membrane water electrolysis hydrogen production against reverse current under intermittent electrolysis conditions at high current density in 1M KOH;

[0085] In-situ Raman results show that (Figure Figure 8 In 1M KOH, with the increase of applied potential, a peak at 683 cm -1 , which is attributed to CoFeOOH species, appeared. The potential at which this phase transition occurred was 1.40 V for NiFe-LDH and 1.35 V for the self-supported electrode for hydrogen production via water electrolysis in anion exchange membrane, compared with NiFe electrode, the introduction of Co reduced the phase transition potential to ~1.35 V vs. RHE, which accelerated the formation of active phase, which was crucial for fast response to current fluctuation.

[0086] In-situ Raman tests under simulated large current density start-stop intermittent electrolysis cycle conditions (Figure Figure 8 The characteristic peaks of the self-supported electrode for hydrogen production via water electrolysis in anion exchange membrane remained stable in multiple 5 min start-stop cycles, and no significant decay was observed, indicating that it had excellent structural integrity under dynamic stress. The peak signal remained reversible between power-on and rest, indicating that the generation and consumption of surface intermediates were relatively rapid. Specifically, the characteristic peak intensity increased during current application, decreased during rest, and could be restored, reflecting the reversible accumulation / consumption of surface intermediates and the reversible reconstruction of the active phase. This reversibility effectively avoids structural corrosion caused by intermediate residues during the rest phase, thereby significantly improving the stability under RC.

[0087] To further reveal the mechanism of the excellent performance of the self-supported electrode for hydrogen production via water electrolysis in anion exchange membrane, attention should be paid to the generation potential of its active species and its evolution rule over time, and the reaction pathway should be revealed by in-situ ATR-SEIRAS spectrum, as shown in Figure Figure 9 .

[0088] Figure 9 In-situ spectral characterization of RC reaction pathway; (a) in-situ ATR-SEIRAS spectra of the self-supported electrode for hydrogen production via water electrolysis in anion exchange membrane at different potentials in 1M KOH; (b) time-dependent in-situ ATR-SEIRAS measurement of the self-supported electrode for hydrogen production via water electrolysis in anion exchange membrane in 1M KOH at a fixed potential of 1.7 V vs RHE;

[0089] Potential-dependent in-situ ATR-SEIRAS spectral results show that (Figure Figure 9 a), in 1M KOH, with the increase of applied potential, the surface of the self-supported electrode for hydrogen production via water electrolysis in anion exchange membrane gradually appeared ·OOH (~1106 cm -1 ), H–O–H (~1670 cm -1 ) and ·OH (~3235 cm-1 further confirmed the phase transformation from hydroxide to oxyhydroxide and the enrichment of key intermediates during the OER process. It is worth noting that the introduction of Co accelerated this phase transformation process.

[0090] Time-dependent in-situ ATR-SEIRAS spectra (a) and the corresponding kinetic plots (b) of Ni-CoFeOOH at 1.7 V vs. RHE Figure 9 further revealed its reaction pathway. At 1.7 V vs. RHE, the synchronous enhancement of the O–H stretching vibration (v OH OH) and the characteristic absorption peak of ·OOH with the extension of reaction time (0-30 min) was observed. However, the typical O–O peroxide vibration peak was not observed, which did not fully match the continuous stepping model of ·OH→·O→·OOH in the single adsorption evolution mechanism (AEM) dominated pathway. Combined with the in-situ infrared characteristic analysis of lattice oxygen participating in the reaction in the literature, the synchronous evolution of ·OH and ·OOH signals, the absence of O–O vibration peaks, and the gradual weakening of surface hydroxyl signals in long-time reactions indicated that there might be a lattice oxygen mechanism (LOM) in the reaction process. In this mechanism, the metal-oxygen bond (M–O) of the active site on the catalyst surface was activated to form oxygen vacancies and release O2, while the ·OOH signal might come from the transition intermediate after the reaction of lattice oxygen, rather than the pure adsorbed oxygen species. This indicated that the high activity of Ni-CoFeOOH might be closely related to the LOM providing an additional reaction path.

[0091] The comprehensive results of in-situ characterization showed that the RC durability advantage of Ni-CoFeOOH could be attributed to the low-potential phase transformation induced by Co doping, which accelerated the construction of the active phase and enabled it to quickly adapt to current fluctuations. At the same time, the robust dynamic balance mechanism of surface intermediates avoided irreversible structural damage during the start-stop cycle. This synergistic effect not only enabled the catalyst to run for a long time under steady-state conditions, but also enabled it to exhibit excellent stability under intermittent electrolysis conditions, thus being able to adapt to fluctuating power inputs in renewable energy-driven water electrolysis systems.

[0092] Performance and stability of the self-supported electrode for anion exchange membrane water electrolysis for hydrogen production prepared in Example 1 in fluctuating power driven AEMWE:

[0093] Finally, to evaluate its potential in renewable energy-driven practical application scenarios, the AEMWE assembled with the self-supported electrode for anion exchange membrane water electrolysis for hydrogen production as the anode and NiPt as the cathode was tested in the RC accelerated stress test cycle simulating fluctuating power, as shown in Figure 10 .

[0094] Figure 10The performance and stability of the AEMWE driven by fluctuating current are shown in the figure. (a) shows the cell voltage curve of the AEMWE after 1750 hours of continuous operation under large fluctuation current density based on the reverse current accelerated stress test scheme; (b) shows the comparison of electrolysis energy consumption and efficiency of AEMWE assembled with NiFe and NiPt as the cathode, respectively, using NiFe as the anode and NiPt as the cathode in anion exchange membrane water electrolysis for hydrogen production; (c) shows the electrolysis energy consumption and efficiency at 500 mA / cm². -2 The estimated cost of producing 1.0 kg of hydrogen under the above conditions; all experiments were conducted at 1 M KOH and room temperature of 25 °C.

[0095] Figure 10 It can be seen that in the RC accelerated stress test cycle simulating fluctuating power ( Figure 10 (a) An AEMWE assembled using a self-supporting electrode resistant to reverse current as the anode and NiPt as the cathode in anion exchange membrane electrolysis for hydrogen production is described in section a) at 2-1.5-1-0.5-0-0.5-1-1.5 A cm⁻¹. -2 It stably operated for over 13,000 cycles (1750 hours) under a large fluctuation in current density cyclic load for one cycle. Notably, even at 2 Acm... -2 At that time, the cell voltage remained stable at approximately 3.1V with minimal fluctuations. The AEMWE cell, used in anion exchange membrane water electrolysis for hydrogen production with a self-supporting electrode assembly resistant to reverse current, achieved 500 mA / cm² under 1 MKOH alkaline conditions, requiring only 2.08V. -2 The current density is significantly lower than the 2.69V required for NiFe anode assembly of AEMWE. Figure 10 As shown in Figure b, at room temperature, the AEMWE of the self-supporting electrode anode used in anion exchange membrane water electrolysis for hydrogen production with reverse current resistance at 500 mA cm⁻¹ -2 Even under these conditions, the operating efficiency can still reach 60%, with energy consumption as low as 4.97 kWh Nm. -3 H2 levels are reduced by approximately 30% compared to the NiFe anode system. Economic analysis ( Figure 10 (c) further indicates that the system operates at 500 mA / cm². -2 The cost of producing one gallon of gasoline equivalent (GGE) H2 at room temperature is only $1.11. These results demonstrate that the self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production maintains high efficiency and stable electrolysis performance even under significantly fluctuating current densities, fully proving its excellent adaptability and long-term durability in practical applications driven by renewable energy.

Claims

1. A method for the preparation of a self-supporting electrode for use in the hydrogen production by water electrolysis in anion exchange membranes, characterized in that The preparation method is specifically completed according to the following steps: I. The nickel felt is cleaned to remove the surface oxide layer, and the pretreated nickel felt is obtained; II. The FeS2 powder is ground into fine powder in a mortar, and then the FeS2 fine powder and CoCl2·6H2O are dispersed in anhydrous ethanol, and ultrasonic dispersion is performed to obtain a uniformly dispersed precursor solution; III. The precursor solution is added dropwise on the pretreated nickel felt, and then placed in a vacuum drying box for vacuum drying to obtain a dried sample; IV. The dried sample is placed in a tube furnace, and then high-temperature annealing treatment is performed under a nitrogen atmosphere to obtain a conductive (NiCoFe)9S8 electrode; V. The conductive (NiCoFe)9S8 electrode is placed in a KOH electrolyte, and the conductive (NiCoFe)9S8 electrode is treated under a constant current to obtain an anti-reverse current self-supporting electrode for water electrolysis for hydrogen production by anion exchange membrane.

2. A method for preparing a self-supporting electrode for use in water electrolysis for hydrogen production in anion exchange membranes against reverse current, according to claim 1, characterized in that In step I, the nickel felt is sequentially cleaned with acetone, hydrochloric acid, anhydrous ethanol and deionized water to remove the surface oxide layer; the mass fraction of the hydrochloric acid is 37%; in step I, the thickness of the nickel felt is 0.4 mm, and the size is 1 cm×1.2 cm.

3. A method for preparing a self-supporting electrode for use in water electrolysis for hydrogen production in anion exchange membranes against reverse current, according to claim 1, characterized in that In step II, the mass of the FeS2 fine powder to the volume of the anhydrous ethanol is (3.36 mg~70 mg):(48 μL~1000 μL); the mass of the CoCl2·6H2O to the volume of the anhydrous ethanol is (6.66 mg~138.5 mg):(48 μL~1000 μL).

4. A method for preparing a self-supporting electrode for use in water electrolysis for hydrogen production in anion exchange membranes against reverse current, according to claim 1, characterized in that In step II, the ultrasonic dispersion time is 30 min~50 min.

5. A method for preparing a self-supporting electrode for use in water electrolysis for hydrogen production in anion exchange membranes against reverse current, according to claim 1, characterized in that The dropwise addition amount of the precursor solution described in Step three is 1 mg / cm 2 5 mg / cm 2 .

6. A method for preparing a self-supporting electrode for use in water electrolysis for hydrogen production in anion exchange membranes against reverse current, according to claim 1, characterized in that In step III, the vacuum drying temperature is 60℃~80℃, and the vacuum drying time is 6h~8h.

7. The method according to claim 1, wherein the method is characterized by In step IV, the high-temperature annealing temperature is 450℃~850℃, and the high-temperature annealing time is 2h~6h.

8. The method according to claim 1, wherein the method is characterized by The constant current in step five is 0.5 A cm -2 ~2 A cm -2 The concentration of the KOH electrolyte in step five is 1 mol / L~6 mol / L.

9. A method for preparing a self-supporting electrode for use in water electrolysis for hydrogen production in anion exchange membranes against reverse current, according to claim 1, characterized in that In step V, the conductive (NiCoFe)9S8 electrode is placed in a KOH electrolyte, and the conductive (NiCoFe)9S8 electrode is treated under a constant current for 3h~7h.

10. The use of the self-supporting electrode prepared by the preparation method according to claim 1 for the anion exchange membrane electrolysis of water to produce hydrogen, characterized in that The anti-reverse current self-supporting electrode for water electrolysis for hydrogen production by anion exchange membrane is used for water electrolysis for hydrogen production.

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