A preparation method and application of a self-supporting electrode for resisting reverse current in hydrogen production by electrolysis of water using an anion exchange membrane

Abstract

A method for preparing and applying a self-supporting electrode resistant to reverse current in anion exchange membrane electrolysis for hydrogen production is disclosed. This invention relates to a method for preparing and applying an electrode. The self-supporting (NiCoFe)9S8 electrode is constructed using a directional solid-phase synthesis strategy to overcome the challenge of electrolyzer performance degradation. First, a precursor solution of FeS2 and CoCl2 is deposited on a nickel felt substrate, followed by annealing to obtain uniformly grown (NiCoFe)9S8. This method not only ensures the uniform distribution of the multi-metal components but also constructs a strong chemical bond and efficient charge transfer between the catalyst layer and the conductive substrate through solid-phase interfacial reactions, effectively avoiding interfacial impedance caused by the introduction of additional binders. This enables high current density water electrolysis for hydrogen production under intermittent power supply fluctuations. In 1 M KOH, this electrode achieves a current density of 500 mA / cm². ‑2 The tank voltage showed almost no decay after 2000 hours of steady-state operation.

Description

Technical Field

[0001] This invention relates to a method for preparing an electrode and its application. Background Technology

[0002] Hydrogen energy, as a clean, efficient, and sustainable secondary energy source, can be obtained through multiple pathways and is an important carrier for building a clean and low-carbon energy structure in the future. Currently, although hydrogen production from fossil fuels is low-cost, it has high carbon emissions; coal-based hydrogen production emits more than 16 kg of CO2 per kg of hydrogen produced. Water electrolysis hydrogen production technology uses H2 as an energy storage medium, enabling grid-scale hydrogen production and achieving efficient utilization of intermittent surplus renewable energy. Its carbon emission level is extremely low, and technological breakthroughs are expected in the near future.

[0003] Currently, the main technologies for hydrogen production through water electrolysis 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). Among these, AWE is the earliest industrialized water electrolysis technology with decades of application experience and is the most mature. PEMWE technology, on the other hand, features a compact structure and rapid kinetic response, which can more efficiently meet the rapid storage needs of intermittent energy sources, thereby reducing the overall cost of green hydrogen production. This technology is now largely mature and has achieved initial commercialization. However, its high equipment cost, reliance on precious metal catalysts, and insufficient research accumulation in core materials such as proton exchange membranes in my country still restrict the large-scale promotion of this technology in the domestic market.

[0004] Among various hydrogen production technologies, water electrolysis driven by renewable energy is a sustainable and environmentally friendly "green hydrogen" production method. AEMWE, as a next-generation water electrolysis technology, has received increasing attention in recent years. AEMWE not only integrates the advantages of PEMWE in high current density output, rapid dynamic response, and compact system integration, but also, compared to traditional AWE, allows the use of non-precious metal catalysts (such as Ni, Fe, and Co-based materials) and low-cost porous electrodes and polymer membrane materials under alkaline operating conditions, thus significantly reducing the overall system cost. With its combination of performance and economic efficiency, AEMWE demonstrates promising application prospects and is widely considered an important development direction for next-generation green hydrogen production technology.

[0005] Despite significant progress in catalyst development and electrolyzer configuration in recent years, the operational stability of AEMWE under real-world renewable energy coupling conditions still faces major challenges. Unlike the steady-state operation mode under stable grid power supply, renewable energy-driven AEMWE systems often face complex dynamic conditions such as large current fluctuations, frequent start-ups and shutdowns, and unpredictable load surges. 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 increases in local potential, but also accelerate the structural collapse of the catalyst and the dissolution of active materials, leading to catalyst layer detachment. In particular, a sudden increase in current can generate a large number of bubbles on the electrode surface. These bubbles can easily clog active sites, deteriorate interfacial mass transfer behavior, and further exacerbate the accumulation of interfacial stress. During repeated reduction-reoxidation and dissolution-redeposition processes, the synergistic effect of interfacial stress and mass migration promotes local structural collapse and induces the formation of a dense inert capping layer, hindering electrolyte penetration and reactant diffusion. The combined effect of these multiple factors ultimately significantly reduces electrode activity and stability, accelerating the performance degradation of the electrolyzer. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production, and its application in water electrolysis for hydrogen production.

[0007] This invention overcomes the aforementioned challenges by employing a directional solid-state synthesis strategy to construct a self-supporting (NiCoFe)9S8 electrode. First, a precursor solution of FeS2 and CoCl2 is deposited on a nickel felt substrate, followed by annealing to obtain uniformly grown (NiCoFe)9S8. This method not only ensures the uniform distribution of the multi-metallic components but also establishes a strong chemical bond and efficient charge transfer between the catalyst layer and the conductive substrate through solid-state interfacial reactions. This effectively avoids interfacial impedance caused by the introduction of additional binders, thereby achieving high-current-density water electrolysis for hydrogen production under intermittent power supply fluctuations.

[0008] A method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production is specifically carried out according to the following steps:

[0009] 1. Clean the nickel felt to remove the oxide layer on the surface, and obtain the pretreated nickel felt;

[0010] 2. Grind FeS2 powder into fine powder in a mortar, then disperse the FeS2 fine powder and CoCl2·6H2O in anhydrous ethanol and disperse by ultrasonication to obtain a uniformly dispersed precursor solution.

[0011] 3. The precursor solution is dropped onto the pretreated nickel felt and then placed in a vacuum drying oven for vacuum drying to obtain the dried sample.

[0012] 4. Place the dried sample in a tube furnace and then perform high-temperature annealing under a nitrogen atmosphere to obtain a conductive (NiCoFe)9S8 electrode.

[0013] 5. The conductive (NiCoFe)9S8 electrode is placed in KOH electrolyte and treated under constant current to obtain a self-supporting electrode resistant to reverse current for use in anion exchange membrane electrolysis of water to produce hydrogen.

[0014] The self-supporting electrode for resisting reverse current in anion exchange membrane electrolysis of water to produce hydrogen is used in the electrolysis of water to produce hydrogen.

[0015] Advantages of this invention:

[0016] I. This invention utilizes a directional solid-phase synthesis combined with an electrochemical activation strategy to prepare a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production. This electrode is an amorphous CoFeOOH shell / conductive (NiCoFe)9S8 core, possessing both abundant active sites and excellent electron transport capabilities. Under reverse current (RC) conditions, this structure significantly reduces the reverse current peak and potential transients, inhibiting rapid reduction and dissolution of active materials. In 1 M KOH, this electrode exhibits resistance to reverse current at 500 mA / cm². -2 After 2000 hours of steady-state operation, the tank voltage showed almost no decay; after 1100 hours of operation under 10-minute start-stop intermittent cycles, the voltage decay rate was only 0.03 mV / h. -1 Its stability is superior to most reported advanced non-precious metal OER electrodes, fully demonstrating its resistance to RC corrosion and long-term durability under steady-state and fluctuating conditions.

[0017] II. The assembled AEMWE system under accelerated stress test conditions (2-1.5-1-0.5-0-0.5-1-1.5Acm) -2 It can stably run for over 13,000 cycles (1750 hours) with an 8-minute cycle time, and only requires 2.08 V to drive a 500mA cm. -2 With a current density and energy efficiency of up to 60%, energy consumption is reduced by approximately 30% compared to commercial NiFe anode systems, and hydrogen production costs are as low as $1.11 / GGE. A large-size monolithic electrode was further scaled up and successfully applied to a solid polymer anion exchange membrane electrolysis (AEMWE) device. This electrode is compatible with mainstream AEM electrolyzer models and is expected to be widely adopted and demonstrated in large-scale green hydrogen production scenarios. Attached Figure Description

[0018] Figure 1The 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.

[0019] Figure 2 The image shows the characterization of the self-supporting electrode against reverse current prepared in Example 1 for hydrogen production by anion exchange membrane electrolysis. In the image, (a) is a TEM image, (b) is a HRTEM image, and (cg) is the EDS result.

[0020] Figure 3 To illustrate the electrochemical behavior of the self-supporting electrode prepared in Example 1 for hydrogen production via anion exchange membrane water electrolysis in a three-electrode system under reverse current conditions, Figure (a) shows the self-supporting electrode for hydrogen production via anion exchange membrane water electrolysis under stable start-stop cycling conditions (1 A cm⁻¹). -2 (a) Reverse potential change curves for 2 consecutive hours (5 min start / stop); (b) Schematic diagram of active material conversion pathways that the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production may undergo during frequent start-stop processes; (c) Comparison of potential responses of commercial NiFe anode and self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production at different current densities; (d) Comparison of RC values ​​between commercial NiFe anode and self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production.

[0021] 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.

[0022] 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;

[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 9The in-situ spectroscopic characterization of the anti-RC reaction pathway is shown in the figure. (a) shows the in-situ ATR-SEIRAS spectra of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production at different potentials in 1M KOH. (b) shows the time-dependent in-situ ATR-SEIRAS measurements of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production at 1M KOH with a fixed potential of 1.7 V vs RHE.

[0027] Figure 10 The 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 conditions of AEMWE; all the above experiments were conducted under the conditions of 1 M KOH and room temperature of 25 °C. Detailed Implementation

[0028] Specific Implementation Method 1: This implementation method describes a method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production. The method is specifically completed according to the following steps:

[0029] 1. Clean the nickel felt to remove the oxide layer on the surface, and obtain the pretreated nickel felt;

[0030] 2. Grind FeS2 powder into fine powder in a mortar, then disperse the FeS2 fine powder and CoCl2·6H2O in anhydrous ethanol and disperse by ultrasonication to obtain a uniformly dispersed precursor solution.

[0031] 3. The precursor solution is dropped onto the pretreated nickel felt and then placed in a vacuum drying oven for vacuum drying to obtain the dried sample.

[0032] 4. Place the dried sample in a tube furnace and then perform high-temperature annealing under a nitrogen atmosphere to obtain a conductive (NiCoFe)9S8 electrode.

[0033] 5. The conductive (NiCoFe)9S8 electrode is placed in KOH electrolyte and treated under constant current to obtain a self-supporting electrode resistant to reverse current for use in anion exchange membrane electrolysis of water to produce hydrogen.

[0034] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: in step one, acetone, hydrochloric acid, anhydrous ethanol, and deionized water are used sequentially to clean the nickel felt to remove the oxide layer on the surface; the mass fraction of the hydrochloric acid is 37%; the thickness of the nickel felt in step one is 0.4 mm, and its size is 1 cm × 1.2 cm. Other steps are the same as in Specific Implementation Method One.

[0035] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that: the mass ratio of FeS2 fine powder to anhydrous ethanol in step two is (3.36 mg~70 mg): (48 μL~1000 μL); the mass ratio of CoCl2·6H2O to anhydrous ethanol in step two is (6.66 mg~138.5 mg): (48 μL~1000 μL). The other steps are the same as in Specific Implementation Method One or Two.

[0036] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the ultrasonic dispersion time in step two is 30 to 50 minutes. The other steps are the same as in Specific Implementation Methods One to Three.

[0037] Specific Implementation Method Five: The difference between this implementation method and Specific Implementation Methods One to Four is that the amount of precursor solution added in step three is 1 mg / cm³. 2 ~5mg / cm 2 The other steps are the same as those in implementation methods one through four.

[0038] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the vacuum drying temperature in step three is 60℃~80℃, and the vacuum drying time is 6h~8h. The other steps are the same as in Specific Implementation Methods One to Five.

[0039] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that the high-temperature annealing temperature in step four is 450℃~850℃, and the high-temperature annealing time is 2h~6h. The other steps are the same as in Specific Implementation Methods One to Six.

[0040] Specific Implementation Method Eight: The difference between this implementation method and Specific Implementation Methods One through Seven is that the constant current mentioned in step five is 0.5A cm. -2 ~2A cm -2 The concentration of the KOH electrolyte mentioned in step five is 1 mol / L to 6 mol / L. Other steps are the same as in specific embodiments one through seven.

[0041] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: in step five, the conductive (NiCoFe)9S8 electrode is placed in KOH electrolyte and treated under constant current for 3 to 7 hours. The other steps are the same as in Specific Implementation Methods One to Eight.

[0042] Specific Implementation Method 10: This implementation method uses a self-supporting electrode resistant to reverse current in the process of anion exchange membrane electrolysis for hydrogen production.

[0043] The beneficial effects of the present invention are verified using the following embodiments:

[0044] Example 1: A method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production, specifically completed according to the following steps:

[0045] 1. Clean the nickel felt to remove the oxide layer on the surface, and obtain the pretreated nickel felt;

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

[0047] The nickel felt mentioned in step one has a thickness of 0.4 mm and a size of 1 cm × 1.2 cm;

[0048] 2. Grind FeS2 powder into fine powder in a mortar, then disperse the FeS2 fine powder and CoCl2·6H2O in anhydrous ethanol and ultrasonically disperse for 45 min to obtain a uniformly dispersed precursor solution.

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

[0050] The mass ratio of CoCl2·6H2O to anhydrous ethanol in step two is 6.66 mg: 48 μL.

[0051] 3. The precursor solution was dropped onto the pretreated nickel felt and then placed in a vacuum drying oven at 80°C for 6 hours to obtain the dried sample.

[0052] The amount of precursor solution added in step three is 4 mg / cm³. 2 ;

[0053] 4. Place the dried sample in a tube furnace and then perform high-temperature annealing under a nitrogen atmosphere to obtain a conductive (NiCoFe)9S8 electrode.

[0054] The high-temperature annealing temperature in step four is 750℃, and the high-temperature annealing time is 4 hours.

[0055] 5. Place the conductive (NiCoFe)9S8 electrode in a 1 mol / L KOH electrolyte solution, at 1 A cm⁻¹ -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 chromatogram (CG) showed that during electrochemical activation, sulfur (S) gradually dissolved from (NiCoFe)9S8. This in-situ dissolution of S helped alleviate lattice stress, thereby inhibiting the dissolution of the active material Fe. Simultaneously, Ni, Co, and Fe were uniformly distributed in the catalyst without significant component separation, indicating that the directional solid-phase synthesis strategy can achieve uniform doping of multiple metal elements at the nanoscale. During this process, surface sulfides were gradually oxidized to Ni-Co-FeOOH-rich hydroxyl oxides, while the core (NiCoFe)9S8 remained as a highly conductive framework. This "core / shell" structure not only significantly enhanced the hydrophilic oxidation ability of the surface active sites but also provided excellent electron transport channels through the conductive sulfide core, thus synergistically optimizing the overall electrocatalytic performance.

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

[0061] To systematically evaluate the electrochemical behavior of a reverse current-resistant self-supporting electrode used in anion exchange membrane water electrolysis for hydrogen production under RC conditions induced by frequent start / stop cycles, it was studied in a three-electrode system. In the 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 1 M KOH solution as the electrolyte.

[0062] Figure 3 To illustrate the electrochemical behavior of the self-supporting electrode prepared in Example 1 for hydrogen production via anion exchange membrane water electrolysis in a three-electrode system under reverse current conditions, Figure (a) shows the self-supporting electrode for hydrogen production via anion exchange membrane water electrolysis under stable start-stop cycling conditions (1 A cm⁻¹). -2 (a) Reverse potential change curves for 2 consecutive hours (5 min start / stop); (b) Schematic diagram of active material conversion pathways that the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production may undergo during frequent start-stop processes; (c) Comparison of potential responses of commercial NiFe anode and self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production at different current densities; (d) Comparison of RC values ​​between commercial NiFe anode and self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production.

[0063] from Figure 3 It can be seen that: at 1Acm -2 During a 5-minute start-up / stop cycle experiment at a current density, the self-supporting electrode resisting reverse current in anion exchange membrane water electrolysis for hydrogen production exhibited a highly repeatable reverse potential during a continuous 2-hour test. Figure 3(a) At the moment of shutdown, the potential rapidly drops to approximately -0.1V vs. RHE, indicating that the RC effect induces reverse polarization. This lower reverse potential primarily drives the reduction of the surface metal active material hydroxyl oxide (M-OOH), generating the low-valence metal active material hydroxide (M(OH)2). During intermittent potential recovery operation, these low-valence active materials are re-oxidized, forming a reversible surface structure dynamic reconstruction cycle. Figure 3 (b) This reversible dynamic reconfiguration maintains or even improves OER performance.

[0064] Further comparison of the response potentials of commercial NiFe anodes and self-supporting electrodes resistant to reverse current used in anion exchange membrane water electrolysis for hydrogen production at different current densities. Figure 3 (c) It was found that the self-supporting electrode resistant to reverse current, used in anion exchange membrane water electrolysis for hydrogen production, consistently exhibited a lower anode potential during constant current operation. (1 A cm⁻¹) -2 For example, the self-supporting electrode against reverse current used in anion exchange membrane electrolysis for hydrogen production can reduce the potential of a commercial NiFe anode from 1.70 V vs. RHE to 1.45 V vs. RHE, reducing energy consumption by approximately 15%. Furthermore, during shutdown transients, the potential drop of the self-supporting electrode against reverse current in anion exchange membrane electrolysis for hydrogen production is more moderate, indicating a relatively small reverse polarization driving force under RC induction. This advantage is also reflected in the reverse current density curve (…). Figure 3 In the middle (d), commercial NiFe anodes exhibited high instantaneous RC peak values ​​(approximately -20 mA / cm) at different current densities. -2 @1Acm -2 The RC peak value of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production was significantly reduced. This indicates that the reverse electron transport rate at the interface of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production is suppressed, exhibiting a similar effect to a "surface potential passivation layer," thus effectively resisting reverse potential corrosion. This difference may stem from the presence of an amorphous CoFeOOH layer on its surface, which has a high charge buffering capacity. 3+ / Co 2+ The redox transformation provides a wide buffer zone to store or release electrons, thereby stabilizing the potential and slowing down the rapid RC-induced reduction process, reducing the risk of dissolution of active substances.

[0065] The self-supporting electrode used in anion exchange membrane water electrolysis for hydrogen production exhibits a lower reverse current peak and a smoother potential transient characteristic under RC conditions induced by frequent start / stop cycles, demonstrating its excellent resistance to RC corrosion and reduction stability. This characteristic helps to suppress electrode degradation and loss of active sites caused by the 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 superior to other comparative electrodes. 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 6The 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.

[0076] Figure 6 The results showed that under pressures of 9-15 MPa, the resistivity of the self-supported Ni-CoFeOOH electrode was significantly lower than that of commercial NiFe. This was attributed to the highly conductive (NiCoFe) 9S8 core providing efficient electron channels, the tightly bonded CoFeOOH shell reducing contact resistance, and the in-situ growth on a three-dimensional porous framework enhancing overall conductivity and mechanical stability, preventing interfacial resistance and catalyst layer detachment, thus achieving excellent conductivity. Further investigation was conducted on the conductivity of self-supported and powdered CoFeOOH. Figure 6 (b) It was found that within the same pressure range, the charge transport performance of the self-supporting Ni-CoFeOOH electrode was consistently significantly higher than that of the powder electrode, demonstrating the synergistic strengthening effect of the conductive framework and the chemical bonding interface.

[0077] Interface bonding test ( Figure 6 Figures c and d show that when the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production is subjected to a critical positive force of 2.71 N, Ni-CoFeOOH separates from the Ni felt substrate, while the commercial NiFe electrode requires only 1.26 N. These results indicate that, compared to the NiFe electrode, the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production possesses stronger interfacial stability and mechanical integrity. This strong bonding interface not only improves the structural stability during long-term operation but also provides a guarantee for suppressing catalyst layer exfoliation under high-frequency start-stop conditions.

[0078] Rapid bubble desorption behavior of the self-supporting electrode against reverse current prepared in anion exchange membrane water electrolysis for hydrogen production, as described in Example 1:

[0079] Bubble kinetics tests further revealed the excellent bubble desorption performance of the self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production. (See...) Figure 7 As shown;

[0080] Figure 7The 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.

[0081] Figure 7 Figure a shows the contact angle measurement results at 0s, 30s, and 60s. The contact angle test revealed that the surface of the self-supporting electrode used in anion exchange membrane water electrolysis for hydrogen production is more hydrophilic, mainly due to the presence of LDH structure and hydrophilic groups on the surface. Water droplets penetrate Ni-CoFeOOH more rapidly and are more easily wetted than NiFe. Figure 7 Figure b illustrates the significant difference in bubble adhesion behavior between the reverse-current resistant self-supporting electrode and the commercial NiFe electrode used in anion exchange membrane water electrolysis for hydrogen production. The adhesion curves and corresponding snapshots show that the reverse-current resistant self-supporting electrode exhibits superior bubble desorption characteristics, with a bubble adhesion force of only 0.051 mN, significantly lower than the 0.160 mN of the NiFe electrode. This low adhesion force promotes rapid bubble release at high current densities, reduces the shielding effect, and improves the utilization rate of catalytic active sites. In contrast, the NiFe electrode, due to its higher bubble adhesion force, requires bubbles to grow to a larger size to overcome this adhesion and detach from the electrode surface.

[0082] The origin and reaction pathway of the anti-RC (reverse current resistance) self-supporting electrode prepared in Example 1 for hydrogen production by anion exchange membrane water electrolysis:

[0083] To gain a deeper understanding of the intrinsic mechanism behind the excellent anti-RC stability exhibited by the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production under start-stop intermittent electrolysis conditions, this invention combines in-situ Raman and in-situ ATR-SEIRAS spectroscopy systems to reveal its structural evolution and reaction pathway characteristics. The structural changes of (NiCoFe)9S8 during the electrochemical activation process were analyzed by in-situ Raman spectroscopy, see [link to relevant documentation]. Figure 8 As shown.

[0084] 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.

[0085] In situ Raman results showed ( Figure 8 In (a) and (b), a peak at 683 cm⁻¹ appeared in 1M KOH as the applied potential increased. -1 The peaks are attributed to the CoFeOOH species. The potential for this phase transition is 1.40 V for NiFe-LDH and 1.35 V for the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production. Compared to the NiFe electrode, the introduction of Co reduces the phase transition potential to ~1.35 V vs. RHE, accelerating the formation of the active phase, which is crucial for rapid response to current fluctuations.

[0086] In-situ Raman testing under simulated high current density start-stop intermittent electrolysis cycle conditions ( Figure 8 In (c), the characteristic peak of the self-supporting electrode against reverse current used in anion exchange membrane water electrolysis for hydrogen production remained stable during multiple 5-minute start-stop cycles, without significant attenuation, indicating excellent structural integrity under dynamic stress. The peak signal maintained reversible changes between energization and resting states, suggesting rapid generation and consumption of intermediates on the catalyst surface. Specifically, the characteristic peak intensity increased during current application, weakened during resting, and recovered, reflecting the reversible accumulation / consumption of surface intermediates and the reversible reconstruction of the active phase. This reversibility effectively avoids structural corrosion caused by residual intermediates during the resting phase, thus significantly improving stability under RC conditions.

[0087] To further elucidate the mechanism of the superior performance of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production, it is necessary to focus on the generation potential of its active species and its evolution over time, and to reveal the reaction pathway using in-situ ATR-SEIRAS spectroscopy. (See [link to relevant documentation]). Figure 9 As shown;

[0088] Figure 9 The in-situ spectroscopic characterization of the anti-RC reaction pathway is shown in the figure. (a) shows the in-situ ATR-SEIRAS spectra of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production at different potentials in 1M KOH. (b) shows the time-dependent in-situ ATR-SEIRAS measurements of the self-supporting electrode against reverse current in anion exchange membrane water electrolysis for hydrogen production at 1M KOH with a fixed potential of 1.7 V vs RHE.

[0089] Potential-dependent in-situ ATR-SEIRAS spectral results show that ( Figure 9 (a) In 1M KOH, as the applied potential increases, the surface of the self-supporting electrode used in anion exchange membrane electrolysis for hydrogen production against reverse current gradually shows ·OOH (~1106 cm⁻¹) deposits. -1 H–O–H (~1670cm) -1 ) and ·OH (~3235cm-1 The characteristic absorption peaks of the sample further confirm that Ni-CoFeOOH undergoes a phase transition from hydroxide to oxyhydroxyl during the OER process, accompanied by the enrichment of key intermediates. Notably, the introduction of Co accelerates this phase transition process.

[0090] Time-dependent in-situ ATR-SEIRAS spectroscopy Figure 9 (b) further reveals its reaction pathway. Under a bias voltage of 1.7 V, with the extension of reaction time (0-30 min), the O–H stretching vibration of ·OH (v) increases. OH The simultaneous enhancement of the characteristic absorption peaks of ·OH and ·OOH was observed. However, the typical vibrational peak of O–O peroxides was not present, which is not entirely consistent with the continuous step model of ·OH→·O→·OOH under the single adsorption evolution mechanism (AEM) dominant pathway. Combined with the in-situ infrared characteristic analysis of lattice oxygen participation in the reaction in the literature, this simultaneous evolution of ·OH and ·OOH signals, the absence of the O–O vibrational peak, and the gradual weakening of the surface hydroxyl signal during long-term reaction indicate that a lattice oxygen mechanism (LOM) may exist in the reaction process. Under this mechanism, the metal-oxygen bond (M–O) at the active site on the catalyst surface is activated, forming oxygen vacancies and releasing O2, while the ·OOH signal may come from the transition intermediate after lattice oxygen participation in the reaction, rather than pure adsorbed oxygen species. This suggests that the high activity of Ni-CoFeOOH may be closely related to the additional reaction pathway provided by LOM.

[0091] Comprehensive in-situ characterization results indicate that the superior RC resistance of Ni-CoFeOOH can be attributed to the low-potential phase transition induced by Co doping, which accelerates the construction of the active phase and enables it to rapidly adapt to current fluctuations. Simultaneously, a robust dynamic equilibrium mechanism of surface intermediates prevents irreversible structural damage during start-stop cycles. This synergistic effect not only enables the catalyst to operate for a long time under steady-state conditions but also allows it to exhibit excellent stability under intermittent electrolysis conditions, thus enabling it to adapt to fluctuating power inputs in renewable energy-driven water electrolysis systems.

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

[0093] Finally, to assess its potential in practical applications driven by renewable energy, an AEMWE assembly, using a reverse current-resistant self-supporting electrode (used in anion exchange membrane water electrolysis for hydrogen production) as the anode and NiPt as the cathode, was tested in an RC accelerated stress test cycle simulating fluctuating power. (See attached image.) Figure 10 As shown;

[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 preparing a self-supporting electrode resistant to reverse current in anion exchange membrane electrolysis for hydrogen production, characterized in that... The preparation method is specifically carried out according to the following steps:

1. Clean the nickel felt to remove the oxide layer on the surface, and obtain the pretreated nickel felt; 2. Grind FeS2 powder into fine powder in a mortar, then disperse the FeS2 fine powder and CoCl2·6H2O in anhydrous ethanol and disperse by ultrasonication to obtain a uniformly dispersed precursor solution. The mass ratio of the FeS2 fine powder to the volume ratio of anhydrous ethanol in step two is (3.36 mg ~ 70 mg): (48 μL ~ 1000 μL); The mass ratio of CoCl2·6H2O to anhydrous ethanol in step two is (6.66 mg~138.5 mg):(48 μL~1000 μL).

3. The precursor solution is dropped onto the pretreated nickel felt and then placed in a vacuum drying oven for vacuum drying to obtain the dried sample.

4. Place the dried sample in a tube furnace and then perform high-temperature annealing under a nitrogen atmosphere to obtain a conductive (NiCoFe)9S8 electrode. The high-temperature annealing temperature in step four is 450℃~850℃, and the high-temperature annealing time is 2h~6h; 5. The conductive (NiCoFe)9S8 electrode was placed in KOH electrolyte and treated under constant current to obtain a self-supporting electrode resistant to reverse current for use in anion exchange membrane electrolysis of water to produce hydrogen.

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

3. The method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane electrolysis for hydrogen production, as described in claim 1, is characterized in that... The ultrasonic dispersion time mentioned in step two is 30 min to 50 min.

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

5. The method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane water electrolysis for hydrogen production according to claim 1, characterized in that... The vacuum drying temperature in step three is 60℃~80℃, and the vacuum drying time is 6h~8h.

6. The method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane electrolysis for hydrogen production, as described in claim 1, is characterized in that... 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.

7. A method for preparing a self-supporting electrode resistant to reverse current in anion exchange membrane electrolysis for hydrogen production, as described in claim 1, characterized in that... In step five, the conductive (NiCoFe)9S8 electrode is placed in KOH electrolyte and treated under constant current for 3 to 7 hours.

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

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