An off-grid alkaline hydrogen production electrocatalyst coupling lattice hydrogen with gradient layered structure, and a preparation method and application thereof
Patent Information
- Application Number
- CN202610702906.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-21
- Publication Date
- 2026-08-28
AI Technical Summary
与此同时，除了稳定性问题，碱性环境下的析氢反应（HER）动力学缓慢同样是制约整体性能的关键瓶颈
[0026] The beneficial results of this invention are as follows: It provides an alkaline hydrogen production electrocatalyst that couples lattice hydrogen with a gradient layered structure. First, the intercalation/deintercalation ability of lattice hydrogen is enhanced through the transition metal oxide (MnO2)/WC interface, while the oxyphilic metal (Ni or Ru)/WC gradient layered interface promotes water dissociation and electron redistribution, enabling the catalyst to exhibit high catalytic activity comparable to commercial Pt/C in the alkaline hydrogen evolution reaction. Second, the gradient layered heterogeneous interface effectively alleviates lattice mismatch and internal stress, significantly suppressing electrode oxidation and reverse current phenomena under intermittent power supply or start-stop conditions, maintaining long-term operational stability even at ampere-level current densities. Furthermore, this strategy, dominated by non-precious metals with low precious metal content, provides a low-cost, high-stability practical solution for off-grid hydrogen production for renewable energy.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of electrocatalytic hydrogen production technology, specifically to an off-grid alkaline electrocatalyst for hydrogen production coupled with lattice hydrogen and a gradient layered structure, its preparation method, and its application. Background Technology
[0002] Producing green hydrogen through renewable energy-driven water electrolysis is a key pathway to achieving deep decarbonization in industries with difficult emissions reduction and mitigating grid intermittency. Among existing hydrogen production technologies, alkaline water electrolysis (AWE) dominates global industrial deployments (market share exceeding 80%) due to its century-long development history, high technological maturity, and cost advantages. However, in actual operation, intermittent power supply from renewable energy sources or planned maintenance shutdowns significantly weaken catalyst stability. Recent research on intermittent alkaline electrolysis (Sha Q., et al., Nature, 2025, 639: 360) has pointed out that such transient conditions can cause severe electrode oxidation and corrosion, highlighting the urgency of improving catalyst stability under intermittent operating conditions. Therefore, it is urgent to develop new strategies that can simultaneously enhance electrocatalytic activity and regulate the countercurrent (RC) phenomenon, starting from the material itself, to fully unleash the potential of AWE in renewable energy systems. This direction remains a research frontier that has not yet been fully explored.
[0003] To address the aforementioned stability challenges, previous studies have attempted to tackle them from different angles. For example, Kim Y. et al. proposed a cathodic protection method that suppresses the oxidation of the Ni electrode during start-up and shutdown by dissolving the sacrificial metal. However, this method inevitably increases system complexity, making it difficult to apply to industrial deployment (Kim Y., et al., JACS Au, 2022, 2: 2491). In contrast, He W. et al. utilized precise control of the interfacial crystal structure to grow a Ni3S2 catalyst layer with a Ni / Ni3S2 gradient heterojunction interface transition layer in situ on a commercial nickel mesh substrate using a hot-injection process. This structure, with its "seamless interface," effectively alleviates lattice mismatch and internal stress between heterogeneous materials, promotes the redistribution of interfacial charges, and thus fundamentally enhances the mechanical and electrochemical stability of the catalyst layer under harsh conditions such as start-up and shutdown, severe potential reversal, and high current density (He W., et al., Journal of the American Chemical Society, 2026, 148:5232). Meanwhile, besides stability issues, the slow kinetics of the hydrogen evolution reaction (HER) under alkaline conditions is also a key bottleneck restricting overall performance. Li B. et al. discovered that by utilizing metal hydrides (TiH... 1.924Lattice hydrogen in the support can significantly enhance the HER rate (Li B., et al., Angewandte Chemie International Edition, 2026, e7288776).
[0004] Therefore, based on the above progress, a catalyst preparation strategy that couples lattice hydrogen with a gradient layered structure to improve the electrocatalytic performance of off-grid alkaline hydrogen production holds promise for simultaneously addressing the stability and activity bottlenecks in industrial deployment: the gradient heterogeneous interface provides the catalyst with structural toughness to withstand harsh operating conditions such as start-up and shutdown, while the lattice hydrogen-mediated mechanism optimizes the hydrogen evolution kinetics from the reaction source. This synergistic design provides a novel material approach for the development of highly efficient alkaline water electrolysis catalysts for intermittent renewable energy. Summary of the Invention
[0005] The purpose of this invention is to address the problems existing in the prior art by providing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure, as well as its preparation method and application.
[0006] To achieve the above objectives, the present invention provides the following technical solution:
[0007] A method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure, characterized by comprising the following steps:
[0008] Step 1: Preparation of dopamine hydrochloride chelate tungstate precursor, specifically including the following steps:
[0009] Step (1): Dissolve tungstate in deionized water, stir for 30 min, and adjust the pH of the resulting solution to 7-10 with an alkaline solution;
[0010] Step (2): Add dopamine hydrochloride (DA) to the solution obtained in step (1) and continue stirring for 30 min; then add ethanol and continue stirring for 12 h.
[0011] Step (3): Collect the precipitate generated by the reaction by centrifugation, wash it thoroughly with deionized water and ethanol in sequence, dry the washed precipitate at 60 °C, and name the product DA-W.
[0012] Step 2: Preparation of Ru(Ni)-MnO2 / WC electrocatalyst, specifically including the following steps:
[0013] Step (1): Disperse DA-W with Ru salt or Ni salt in deionized water, stir in an oil bath and evaporate to dryness, so that Ru... 3+ or Ni 2+ It fully coordinates with DA-W to promote the formation of a gradient layered structure, and the resulting product is named Ru(Ni) / DA-W;
[0014] Step (2): Disperse the Ru(Ni) / DA-W obtained in step (1) and Mn salt in deionized water and stir for 12 h to gradually complex metal ions, which helps to form a heterostructure in the next step. After the reaction is completed, collect the product by centrifugation, wash it with deionized water several times, and then dry it under vacuum for 12 h.
[0015] Step (3): Anneal the dried product at 400-1000 °C for 2-6 h under a specific atmosphere; then leach the obtained material in 1.0 M KOH for 4-12 h to remove unstable components; finally, wash until neutral and dry to obtain Ru(Ni)-MnO2 / WC electrocatalyst.
[0016] Furthermore, in step one, the tungstate is selected from sodium tungstate or ammonium tungstate; the alkaline solution is selected from ammonia, NaOH or KOH.
[0017] Further, in step one, the concentration of the tungstate in deionized water is 1~50 mg / mL. -1 The concentration of dopamine hydrochloride in the solution is 1-50 mg / mL. -1 .
[0018] Furthermore, in step two, the Ru salt or Ni salt is one of RuCl3, Ru(acac)3, K2RuCl5, NiCl2, or Ni(acac)2.
[0019] Furthermore, in step two, the concentration of DA-W in deionized water is 1~10 mg / mL. -1 The concentration of the Ru or Ni salt in deionized water is 0.1~10 mg / mL. -1 .
[0020] Furthermore, in step two, the oil bath temperature is 80~150°C. o C.
[0021] Furthermore, in step two, the Mn salt is one of MnCl2, Mn(acac)2, or Mn(CH3COO)2.
[0022] Furthermore, in step two, the concentration of Ru(Ni) / DA-W in deionized water is 1~10 mg / mL. -1 The concentration of the Mn salt dispersed in deionized water is 0.1~1 mg / mL. -1 .
[0023] Furthermore, in step two, the specific atmosphere is one or more of nitrogen, argon, and hydrogen.
[0024] A second aspect of the present invention provides an off-grid alkaline electrocatalyst for hydrogen production that couples lattice hydrogen with a gradient layered structure.
[0025] A third aspect of the present invention provides an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure for use in hydrogen evolution and other hydrogen electrode reactions at the cathode of water electrolysis.
[0026] The beneficial results of this invention are as follows: It provides an alkaline hydrogen production electrocatalyst that couples lattice hydrogen with a gradient layered structure. First, the intercalation / deintercalation ability of lattice hydrogen is enhanced through the transition metal oxide (MnO2) / WC interface, while the oxyphilic metal (Ni or Ru) / WC gradient layered interface promotes water dissociation and electron redistribution, enabling the catalyst to exhibit high catalytic activity comparable to commercial Pt / C in the alkaline hydrogen evolution reaction. Second, the gradient layered heterogeneous interface effectively alleviates lattice mismatch and internal stress, significantly suppressing electrode oxidation and reverse current phenomena under intermittent power supply or start-stop conditions, maintaining long-term operational stability even at ampere-level current densities. Furthermore, this strategy, dominated by non-precious metals with low precious metal content, provides a low-cost, high-stability practical solution for off-grid hydrogen production for renewable energy. Attached Figure Description
[0027] Figure 1 This is an elemental mapping of an off-grid alkaline hydrogen production electrocatalyst with coupled lattice hydrogen and gradient layered structure in Example 1 of this invention.
[0028] Figure 2 This is the current-time response curve of an off-grid alkaline hydrogen production electrocatalyst with coupled lattice hydrogen and gradient layered structure in Example 1 of the present invention for catalyzing H2 at high potential;
[0029] Figure 3 This is an in-situ Raman image of an off-grid alkaline hydrogen production electrocatalyst with coupled lattice hydrogen and gradient layered structure in Example 1 of this invention, analyzing MnO2H x The formation of lattice hydrogen. Detailed Implementation
[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0031] Example 1:
[0032] Step 1: Preparation of dopamine hydrochloride chelate tungstate precursor, specifically including the following steps:
[0033] Step (1): Dissolve 142 mg of ammonium tungstate in 40 mL of deionized water, stir for 30 min, and adjust the pH of the resulting solution to 8 with ammonia solution;
[0034] Step (2): Add 189 mg of dopamine hydrochloride to the solution obtained in step (1) and continue stirring for 30 min. Then add ethanol and continue stirring for 12 h.
[0035] Step (3): Collect the precipitate generated by the reaction by centrifugation, wash it thoroughly with deionized water and ethanol in sequence, dry the washed precipitate at 60 °C, and name the product DA-W.
[0036] Step 2: Preparation of Ru-MnO2 / WC electrocatalyst, specifically including the following steps:
[0037] Step (1): Disperse 100 mg DA-W and 20 mg RuCl3 in 20 mL of deionized water, and then... o Stir and evaporate to dryness in an oil bath, so that Ru 3+ It fully coordinates with DA-W to promote the formation of a gradient layered structure, and the resulting product is named Ru / DA-W;
[0038] Step (2): Disperse 100 mg Ru / DA-W and 5 mg Mn(CH3COO)2 obtained in the previous step in 25 mL of deionized water and stir for 12 h to gradually complex metal ions, which helps in the subsequent formation of heterostructures. After the reaction is complete, collect the product by centrifugation, wash it several times with deionized water, and then dry it under vacuum for 12 h.
[0039] Step (3): The dried product was annealed at 600 °C for 4 h under a specific atmosphere. Subsequently, the obtained material was leached in 1.0 M KOH for 4 h to remove unstable components. Finally, it was washed until neutral and dried to obtain the Ru-MnO2 / WC electrocatalyst.
[0040] like Figure 1 As shown, the mapping results indicate that Ru-MnO2 / WC has a gradient layered structure.
[0041] like Figure 2 As shown, Ru-MnO2 / WC exhibits better stability in catalyzing H2 at high potentials than Pt / C, indicating that it has stronger antioxidant capacity, thus enabling it to maintain normal operation of the catalyst layer under harsh conditions such as start-up, shutdown, and severe potential reversal.
[0042] like Figure 3 As shown, Raman spectroscopy reveals the in-situ formation of MnO2H from Ru-MnO2 / WC. x Lattice hydrogen.
[0043] Example 2:
[0044] Step 1: Preparation of dopamine hydrochloride chelate tungstate precursor, specifically including the following steps:
[0045] Step (1): Dissolve 142 mg of ammonium tungstate in 40 mL of deionized water, stir for 30 min, and adjust the pH of the resulting solution to 8 with ammonia solution;
[0046] Step (2): Add 189 mg of dopamine hydrochloride to the solution obtained in step (1) and continue stirring for 30 min. Then add ethanol and continue stirring for 12 h.
[0047] Step (3): Collect the precipitate generated by the reaction by centrifugation, wash it thoroughly with deionized water and ethanol in sequence, dry the washed precipitate at 60 °C, and name the product DA-W.
[0048] Step 2: Preparation of Ni-MnO2 / WC electrocatalyst, specifically including the following steps:
[0049] Step (1): Disperse 100 mg DA-W and 13 mg NiCl2 in 20 mL of deionized water, and heat at 150 °C. o Stir and evaporate to dryness in a C oil bath to allow Ni to... 2+ The product is fully coordinated with DA-W to promote the formation of a gradient layered structure and is named Ni / DA-W.
[0050] Step (2): Disperse 100 mg Ni / DA-W and 5 mg Mn(CH3COO)2 obtained in the previous step in 25 mL of deionized water and stir for 12 h to gradually complex metal ions, which helps in the subsequent formation of heterostructures. After the reaction is complete, collect the product by centrifugation, wash it several times with deionized water, and then dry it under vacuum for 12 h.
[0051] Step (3): The dried product was annealed at 600 °C for 4 h under a specific atmosphere. Subsequently, the obtained material was leached in 1.0 M KOH for 4 h to remove unstable components. Finally, it was washed until neutral and dried to obtain the Ni-MnO2 / WC electrocatalyst.
[0052] Example 3:
[0053] Step (1): Dissolve 400 mg of ammonium tungstate in 40 mL of deionized water, stir for 30 min, and adjust the pH of the resulting solution to 9 with ammonia solution;
[0054] Step (2): Add 450 mg of dopamine hydrochloride to the solution obtained in step (1) and continue stirring for 30 min. Then add ethanol and continue stirring for 12 h.
[0055] Step (3): Collect the precipitate generated by the reaction by centrifugation, wash it thoroughly with deionized water and ethanol in sequence, dry the washed precipitate at 60 °C, and name the product DA-W.
[0056] Step 2: Preparation of Ru-MnO2 / WC electrocatalyst, specifically including the following steps:
[0057] Step (1): Disperse 200 mg DA-W and 10 mg Ru(acac)3 in 20 mL of deionized water, and heat at 120 °C. o Stir and evaporate to dryness in an oil bath, so that Ru 3+ It fully coordinates with DA-W to promote the formation of a gradient layered structure, and the resulting product is named Ru / DA-W;
[0058] Step (2): Disperse 200 mg Ru / DA-W and 15 mg Mn(acac)2 obtained in the previous step in 25 mL of deionized water and stir for 12 h to gradually complex metal ions, which helps in the subsequent formation of heterostructures. After the reaction is complete, collect the product by centrifugation, wash it several times with deionized water, and then dry it under vacuum for 12 h.
[0059] Step (3): The dried product was annealed at 900 °C for 4 h under a specific atmosphere. Subsequently, the obtained material was leached in 1.0 M KOH for 12 h to remove unstable components. Finally, it was washed until neutral and dried to obtain the Ru-MnO2 / WC electrocatalyst.
[0060] Example 4:
[0061] Step 1: Preparation of dopamine hydrochloride chelate tungstate precursor, specifically including the following steps:
[0062] Step (1): Dissolve 100 mg sodium tungstate in 40 mL of deionized water, stir for 30 min, and adjust the pH of the resulting solution to 10 with NaOH solution;
[0063] Step (2): Add 100 mg of dopamine hydrochloride to the solution obtained in step (1) and continue stirring for 30 min. Then add ethanol and continue stirring for 12 h.
[0064] Step (3): Collect the precipitate generated by the reaction by centrifugation, wash it thoroughly with deionized water and ethanol in sequence, dry the washed precipitate at 60 °C, and name the product DA-W.
[0065] Step 2: Preparation of Ni-MnO2 / WC electrocatalyst, specifically including the following steps:
[0066] Step (1): Disperse 80 mg DA-W and 20 mg Ni(acac)2 in 20 mL of deionized water, and heat at 140 °C. o Stir and evaporate to dryness in a C oil bath to allow Ni to... 2+ The product is fully coordinated with DA-W to promote the formation of a gradient layered structure and is named Ni / DA-W.
[0067] Step (2): Disperse 80 mg Ni / DA-W and 10 mg MnCl2 obtained in the previous step in 25 mL of deionized water and stir for 12 h to gradually complex metal ions, which helps in the subsequent formation of heterostructures. After the reaction is complete, collect the product by centrifugation, wash it several times with deionized water, and then dry it under vacuum for 12 h.
[0068] Step (3): The dried product was annealed at 900 °C for 6 h under a specific atmosphere. Subsequently, the obtained material was leached in 1.0 M KOH for 8 h to remove unstable components. Finally, it was washed until neutral and dried to obtain the Ni-MnO2 / WC electrocatalyst.
[0069] Example 5
[0070] A Ni-MnO2 / WC off-grid alkaline hydrogen production electrocatalyst with coupled lattice hydrogen and a gradient layered structure exhibits an overpotential of 106 mV @ 100 mA cm⁻¹ when applied to the hydrogen evolution reaction at the cathode of a water electrolysis reactor. -2 After 100 hours of cyclic start-up and shutdown in an alkaline electrolyzer, its performance degradation rate was only 0.9 mV / h. -1 It is superior to Pt / C (1.2 mV h) -1 This is mainly attributed to the confinement and protection of the active components by the gradient layered structure, and the continuous insertion and extraction mechanism of H provided by lattice hydrogen, which effectively maintains the catalytic performance during the start-up and shutdown process.
[0071] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
Claims
1. A method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure, characterized in that, Includes the following steps: Step 1: Preparation of dopamine hydrochloride chelate tungstate precursor, specifically including the following steps: Step (1): Dissolve tungstate in deionized water, stir for 30 min, and adjust the pH of the resulting solution to 7-10 with an alkaline solution; Step (2): Add dopamine hydrochloride (DA) to the solution obtained in step (1) and continue stirring for 30 min; then add ethanol and continue stirring for 12 h. Step (3): Collect the precipitate generated by the reaction by centrifugation, wash it thoroughly with deionized water and ethanol in sequence, dry the washed precipitate at 60 °C, and name the product DA-W. Step 2: Preparation of Ru(Ni)-MnO2 / WC electrocatalyst, specifically including the following steps: Step (1): Disperse DA-W with Ru salt or Ni salt in deionized water, stir in an oil bath and evaporate to dryness, so that Ru... 3+ or Ni 2+ It fully coordinates with DA-W to promote the formation of a gradient layered structure, and the resulting product is named Ru(Ni) / DA-W; Step (2): Disperse the Ru(Ni) / DA-W obtained in step (1) and Mn salt in deionized water and stir for 12 h to gradually complex metal ions, which helps to form a heterostructure in the next step. After the reaction is completed, collect the product by centrifugation, wash it with deionized water several times, and then dry it under vacuum for 12 h. Step (3): Anneal the dried product at 400-1000 °C for 2-6 h under a specific atmosphere; then leach the obtained material in 1.0 M KOH for 4-12 h to remove unstable components; finally, wash until neutral and dry to obtain Ru(Ni)-MnO2 / WC electrocatalyst.
2. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step one, the tungstate is selected from sodium tungstate or ammonium tungstate; the alkaline solution is selected from ammonia, NaOH or KOH.
3. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step one, the concentration of the tungstate in deionized water is 1~50 mg / mL. -1 The concentration of dopamine hydrochloride in the solution is 1-50 mg / mL. -1 .
4. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step two, the Ru salt or Ni salt is one of RuCl3, Ru(acac)3, K2RuCl5, NiCl2 or Ni(acac)2.
5. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step two, the concentration of DA-W in deionized water is 1~10 mg / mL. -1 The concentration of the Ru or Ni salt in deionized water is 0.1~10 mg / mL. -1 The oil bath temperature is 80~150℃. o C.
6. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step two, the Mn salt is one of MnCl2, Mn(acac)2 or Mn(CH3COO)2.
7. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step two, the concentration of Ru(Ni) / DA-W in deionized water is 1~10 mg / mL. -1 The concentration of the Mn salt dispersed in deionized water is 0.1~1 mg / mL. -1 .
8. The method for preparing an off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure according to claim 1, characterized in that: In step two, the specific atmosphere is one or more of nitrogen, argon, and hydrogen.
9. An off-grid alkaline hydrogen production electrocatalyst coupled with lattice hydrogen and a gradient layered structure, prepared according to any one of claims 1 to 8.
10. The off-grid alkaline hydrogen production electrocatalyst of claim 9, coupled with a lattice hydrogen and a gradient layered structure, is applied to hydrogen evolution and other hydrogen electrode reactions at the cathode of water electrolysis.