Ni-based non-noble metal hydrogen evolution electrocatalyst and preparation method thereof
Ni-Mo-S ternary composite catalyst was prepared by segmented electrodeposition method to form a porous cluster structure, which solved the problem of insufficient activity and stability of nickel-based catalysts, and achieved low-cost and efficient hydrogen production performance of electrolytic water.
Patent Information
- Application Number
- CN202510586084.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-08
- Publication Date
- 2025-09-02
AI Technical Summary
The existing nickel-based catalysts have low active site utilization rate and poor stability during the electrolysis process, and the cost of precious metal catalysts is high, making it difficult to meet the needs of large-scale production.
A one-step segmented electrodeposition method was used to prepare the Ni-Mo-S ternary composite catalyst, and a porous cluster-like structure was formed by in-situ electrodeposition through gradient segmented current, which optimized the ratio of Ni, Mo, and S and the deposition layer structure, and improved the density and stability of active sites.
It exhibits high catalytic activity and good stability under alkaline conditions, and has a lower cost than precious metal catalysts, making it suitable for industrial applications.
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Figure CN120575221A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of electrocatalyst preparation and application, and specifically to a Ni-based non-noble metal hydrogen evolution electrocatalyst and a preparation method, and more particularly to a preparation method of a clustered Ni-Mo-S ternary composite material and its application in a high-efficiency hydrogen evolution (HER) reaction. Background Art
[0002] Against the backdrop of global advocacy for sustainable development, energy transition is urgent. Hydrogen, as a clean, efficient, and sustainable energy carrier, plays a key role in the future energy system. Water electrolysis is a highly promising large-scale hydrogen production technology, and its core lies in efficient electrocatalysts. However, the development of highly active, stable, and low-cost electrocatalysts in the field of water electrolysis currently faces numerous challenges.
[0003] Traditional precious metal catalysts, such as platinum (Pt), offer excellent water electrolysis performance and can effectively improve reaction kinetics and thus increase efficiency. However, their high price and limited reserves make them difficult to meet the demands of large-scale production and application. Consequently, researchers have focused on developing catalysts with low or no precious metal content. Nickel-based compounds, due to their environmental friendliness, high Earth abundance, low cost, high corrosion resistance, high electrocatalytic performance, and high conductivity, have become promising candidates for replacing the precious metal Pt. However, existing nickel-based catalysts generally suffer from low active site utilization, which hinders their full catalytic activity. Under complex water electrolysis conditions, their stability is poor, and they are prone to structural changes or loss of active components, resulting in a decrease in catalytic performance. Nickel-based catalysts exhibit high overpotentials and slow reaction kinetics during the electrocatalytic hydrogen evolution reaction, with a significant decrease in efficiency, especially at high current densities. To address these issues, several patents have been filed for the preparation and application of sulfide composite electrocatalysts. However, existing synthesis methods for these catalysts often rely on high temperatures and pressures or complex templates, resulting in poor process reproducibility and difficulty in scalability. Furthermore, the catalysts suffer from suboptimal performance, large overpotentials, and short stability. Therefore, further improving the catalytic activity and stability of these catalysts is of great significance. Summary of the Invention
[0004] To address the shortcomings of the existing technology, the present invention provides a Ni-Mo-S ternary composite catalyst, a method for preparing the Ni-Mo-S ternary composite catalyst, and its application in water electrolysis. This method utilizes a one-step, segmented electrodeposition process to produce a nickel-cobalt sulfide hydrogen evolution catalyst. This catalyst exhibits a high number of active sites, high catalytic activity, and good stability when decomposing water to produce hydrogen under alkaline conditions. The preparation process is simple and rapid, and is of great value for future industrial applications.
[0005] The specific technical solutions are as follows: A Ni-based non-precious metal hydrogen evolution electrocatalyst comprises a nickel foam substrate and a Ni-Mo-S ternary composite catalytic material deposition layer deposited on the nickel foam substrate; the Ni-Mo-S ternary composite catalytic material deposition layer exhibits a porous and rough cluster morphology, and the catalyst has hydrogen evolution activity under alkaline conditions.
[0006] The Ni-Mo-S ternary composite catalytic material deposition layer is agglomerated into cluster structures of varying sizes with irregular particles, and secondary small particles are deposited on the surface of the clusters to form abundant pores and a rough interface with uneven surfaces.
[0007] The preparation method of the above-mentioned Ni-based non-precious metal hydrogen evolution electrocatalyst is to use pretreated nickel foam as the substrate, adopt the electrodeposition method, and construct a Ni-Mo-S ternary composite catalytic material by in-situ electrodeposition using a gradient segmented current. The gradient segmented current in-situ electrodeposition includes several different deposition stages, and by setting different current densities between each deposition stage, a porous cluster structure of the Ni-Mo-S ternary composite catalytic material deposition layer is formed.
[0008] Preferably, the current density of the several different deposition stages is increased sequentially, and by controlling the electrodeposition time of different deposition stages, the ratio optimization of Ni, Mo, and S and the optimization of the cluster structure in the Ni-Mo-S ternary composite catalytic material deposition layer are achieved.
[0009] The preparation method of the above-mentioned Ni-based non-noble metal hydrogen evolution electrocatalyst specifically comprises the following steps: a. Substrate pretreatment: Nickel foam was used as the substrate and cut into pieces of 1 × 1.5 cm in size. The nickel foam was then ultrasonically cleaned in 1.0 M HCl, ethanol, and deionized water for 10 min each, and then vacuum-dried for later use. b. Preparation of an electrodeposition solution: The pretreated nickel foam obtained in step a was used as a cathode, and an electrolyte comprising NiSO4·6H2O as a nickel source, Na2MoO4·2H2O as a molybdenum source, and CH4N2S as a sulfur source was prepared as an electrodeposition solution. H3BO3 was added as a buffer, C6H5Na3O7·3H2O (trisodium citrate trihydrate) as a complexing agent, and NaCl as a conductive salt. The pH of the solution was adjusted to 4.0 with HCl. c. Staged electrodeposition: Using the pretreated nickel foam as the cathode, four stages of electrodeposition were performed sequentially at a constant temperature of 40-50°C. After deposition, the surface residue was immediately washed with deionized water and dried to obtain the final catalyst.
[0010] d. Post-treatment: Immediately after electrodeposition, rinse with deionized water to remove loose surface deposits, and then place in a vacuum drying oven at 60°C to fully dry.
[0011] Preferably, in the preparation of the electrodeposition solution in step b, the HCl concentration is 1~3 M, the NiSO4•6H2O concentration is 0.5 M, the Na2MoO4•2H2O concentration is 0.1~0.3 M, the CH4N2S concentration is 0.1~0.3 M, the H3BO3 concentration is 0.1 M, the C6H5Na3O7·3H2O concentration is 0.1~0.3 M, and the NaCl concentration is 0.5 M.
[0012] Preferably, in the staged electrodeposition of step c, the electrodeposition adopts a two-electrode system, wherein the counter electrode is a titanium plate; the four stages are constant current electrodeposition, and the current densities of the four stages are 10, 25, 40, and 60 mA cm -2 , and the corresponding electrodeposition durations are 10, 15, 20, and 5 minutes, respectively.
[0013] Preferably, the molar ratio of Ni, Mo and S is 5:(1-3):(1-3).
[0014] Preferably, in the preparation of the electrodeposition solution in step b, the pH is adjusted using 1.0 M HCl solution, and the final pH value of the electrolyte is stabilized at 4.0; in step c, the electrolyte temperature is maintained at 45° C. by a constant temperature water bath system.
[0015] As an application of a Ni-based non-noble metal hydrogen evolution electrocatalyst in the present invention, the Ni-based non-noble metal hydrogen evolution electrocatalyst is used as a hydrogen evolution reaction (HER) electrode in an alkaline water electrolysis system.
[0016] As an application of the Ni-based non-precious metal hydrogen evolution electrocatalyst in the present invention, the NiMoS / NF (nickel foam) ternary composite electrode prepared by segmented constant current electrodeposition can be directly used as a working electrode for electrochemical testing. The steps for performing electrochemical testing as a working electrode are as follows: a. Cut the prepared NiMoS / NF ternary composite electrode into small composite electrodes of 1×1.5 cm in size; b. The hydrogen evolution reaction performance test was carried out in a standard three-electrode test system, wherein the small composite electrode described in step a was used as the working electrode, the platinum sheet was used as the counter electrode, the Hg / HgO electrode was used as the reference electrode, and a 1 M KOH solution was used as the electrolyte. The temperature of the electrolyte was 25°C. c. Electrochemical tests were performed on a DH7001B electrochemical workstation. When performing the hydrogen evolution linear voltammetry curve test, the potential scan range relative to the Hg / HgO electrode was -0.5 to -1.8 V, and the scan rate was 10 mVs. -1 The hydrogen evolution chronopotentiometry test was carried out at a current density of 10 mA cm -2 and 100mA cm-2 under the conditions of d. NiMoS / NF ternary composite electrode is used as the working electrode for hydrogen evolution reaction. When the current density is 10 mA cm -2 When the current density is 100 mA cm -2 The hydrogen evolution overpotential is 247 mV. The hydrogen evolution chronopotentiometry test was carried out at current densities of 10 mA cm -2 and 100mA cm -2 The overpotential showed no obvious attenuation after 50 h, and the potential fluctuation range was less than ±5 mV.
[0017] The beneficial effects of the present invention are: First, the present invention's Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method utilizes staged electrodeposition, controlling current densities at varying levels to optimize the structure of the coating (Ni-Mo-S ternary composite catalytic material deposited layer). During the low current density stage, the slow deposition of metal ions reduces internal stress in the coating, promotes uniform grain growth, and significantly improves the adhesion between the coating and the substrate. Furthermore, controlled electrochemical polarization during this stage facilitates substrate surface activation, forming a dense base coating.
[0018] Second, the present invention relates to a Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method. During staged electrodeposition, after transitioning to the high current density stage, the rapid reduction of metal ions leads to a significant increase in the nucleation rate, forming a porous cluster structure based on NiMoS. This is manifested in a porous, rough, cluster-like morphology on the electrode surface. The NiMoS coating is composed of irregular particles agglomerated into clusters of varying sizes. Secondary small particles further accumulate on the cluster surface, forming abundant pores and a rough, uneven interface. This porous, cluster-like morphology significantly increases the specific surface area of the electrode, providing more active sites for the electrocatalytic hydrogen evolution reaction.
[0019] Third, the Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method of the present invention achieve a performance breakthrough through the synergistic effect formed by regulating different current densities in stages: the dense bottom layer established in the low current stage can effectively suppress the plating peeling phenomenon that may occur in the high current stage, further enhancing the stability of the plating, while the porous structure formed in the high current stage increases the active site density and can accelerate the reaction mass transfer by connecting the pores.
[0020] Fourth, the Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method of the present invention offer highly controllable process parameters. By precisely regulating the current density, duration, and conversion gradient at each stage, key parameters such as cluster size (0.5-5 μm) and pore distribution can be precisely controlled to meet the needs of diverse application scenarios.
[0021] Fifth, the present invention provides a Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method, and provides a ternary composite electrode of Ni, Mo, and S prepared by segmented constant current electrodeposition. Tests have shown that it has good performance at both high current density and low current density, and its hydrogen evolution performance and hydrogen evolution stability are close to those of precious metal hydrogen evolution electrocatalyst electrodes, but its cost is greatly reduced compared to precious metal hydrogen evolution electrocatalyst electrodes.
[0022] Sixth, the present invention discloses a Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method. By adopting a one-step preparation method of staged electrodeposition, a NiMoS composite deposition layer with high electrocatalytic activity is formed on the NF foam nickel base. The ratio of Ni, Mo, and S in the deposition layer is controllable, and the preparation process is simple and fast. The prepared electrode has excellent hydrogen evolution activity under alkaline conditions and exhibits good durability. It has broad application prospects and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 This is a scanning electron microscope (SEM) morphology image of the NiMoS / NF electrode of Example 1; Figure 2 Elemental mapping of the NiMoS / NF electrode of Example 1 by scanning electron microscopy (SEM-Mapping); Figure 3 LSV curves of hydrogen evolution performance of different samples in 1 M KOH solution; Figure 4 This is the chronopotentiometry CP curve of hydrogen evolution stability. DETAILED DESCRIPTION
[0024] The following embodiments are further described in conjunction with the accompanying drawings and examples. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.
[0025] like Figures 1 to 4 The figure shows the overall embodiment of a Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method of the present invention. The Ni-based non-precious metal hydrogen evolution electrocatalyst includes a nickel foam substrate and a Ni-Mo-S ternary composite catalytic material deposition layer deposited on the nickel foam substrate; the Ni-Mo-S ternary composite catalytic material deposition layer exhibits a porous and rough cluster morphology, and the catalyst has hydrogen evolution activity under alkaline conditions.
[0026] The Ni-Mo-S ternary composite catalytic material deposition layer is agglomerated into cluster structures of varying sizes with irregular particles, and secondary small particles are deposited on the surface of the clusters to form abundant pores and a rough interface with uneven surfaces.
[0027] The preparation method of the above-mentioned Ni-based non-precious metal hydrogen evolution electrocatalyst is to use pretreated nickel foam as the substrate, adopt the electrodeposition method, and construct a Ni-Mo-S ternary composite catalytic material by in-situ electrodeposition using a gradient segmented current. The gradient segmented current in-situ electrodeposition includes several different deposition stages, and by setting different current densities between each deposition stage, a porous cluster structure of the Ni-Mo-S ternary composite catalytic material deposition layer is formed.
[0028] Preferably, the current density of the several different deposition stages is increased sequentially, and by controlling the electrodeposition time of different deposition stages, the ratio optimization of Ni, Mo, and S and the optimization of the cluster structure in the Ni-Mo-S ternary composite catalytic material deposition layer are achieved.
[0029] The preparation method of the above-mentioned Ni-based non-noble metal hydrogen evolution electrocatalyst specifically comprises the following steps: a. Substrate pretreatment: Nickel foam was used as the substrate and cut into pieces of 1 × 1.5 cm in size. The nickel foam was then ultrasonically cleaned in 1.0 M HCl, ethanol, and deionized water for 10 min each, and then vacuum-dried for later use. b. Preparation of an electrodeposition solution: The pretreated nickel foam obtained in step a was used as a cathode, and an electrolyte comprising NiSO4·6H2O as a nickel source, Na2MoO4·2H2O as a molybdenum source, and CH4N2S as a sulfur source was prepared as an electrodeposition solution. H3BO3 was added as a buffer, C6H5Na3O7·3H2O as a complexing agent, and NaCl as a conductive salt, and the pH of the solution was adjusted to 4.0 with HCl. c. Staged electrodeposition: Using the pretreated nickel foam as the cathode, four stages of electrodeposition were performed sequentially at a constant temperature of 40-50°C. After deposition, the surface residue was immediately washed with deionized water and dried to obtain the final catalyst.
[0030] d. Post-treatment: Immediately after electrodeposition, rinse with deionized water to remove loose surface deposits, and then place in a vacuum drying oven at 60°C to fully dry.
[0031] Preferably, in the preparation of the electrodeposition solution in step b, the HCl concentration is 1~3 M, the NiSO4•6H2O concentration is 0.5 M, the Na2MoO4•2H2O concentration is 0.1~0.3 M, the CH4N2S concentration is 0.1~0.3 M, the H3BO3 concentration is 0.1 M, the C6H5Na3O7·3H2O concentration is 0.1~0.3 M, and the NaCl concentration is 0.5 M.
[0032] Preferably, in the staged electrodeposition of step c, the electrodeposition adopts a two-electrode system, wherein the counter electrode is a titanium plate; the four stages are constant current electrodeposition, and the current densities of the four stages are 10, 25, 40, and 60 mA cm -2 , and the corresponding electrodeposition durations are 10, 15, 20, and 5 minutes, respectively.
[0033] Preferably, the molar ratio of Ni, Mo and S is 5:(1-3):(1-3).
[0034] Preferably, in the preparation of the electrodeposition solution in step b, the pH is adjusted using 1.0 M HCl solution, and the final pH value of the electrolyte is stabilized at 4.0; in step c, the electrolyte temperature is maintained at 45° C. by a constant temperature water bath system.
[0035] As an application of a Ni-based non-noble metal hydrogen evolution electrocatalyst in the present invention, the Ni-based non-noble metal hydrogen evolution electrocatalyst is used as a hydrogen evolution reaction (HER) electrode in an alkaline water electrolysis system.
[0036] As an application of the Ni-based non-precious metal hydrogen evolution electrocatalyst in the present invention, the NiMoS / NF (nickel foam) ternary composite electrode prepared by segmented constant current electrodeposition can be directly used as a working electrode for electrochemical testing. The steps for performing electrochemical testing as a working electrode are as follows: a. Cut the prepared NiMoS / NF ternary composite electrode into small composite electrodes of 1×1.5 cm in size; b. The hydrogen evolution reaction performance test was carried out in a standard three-electrode test system, wherein the small composite electrode described in step a was used as the working electrode, the platinum sheet was used as the counter electrode, the Hg / HgO electrode was used as the reference electrode, and a 1 M KOH solution was used as the electrolyte. The temperature of the electrolyte was 25°C. c. Electrochemical tests were performed on a DH7001B electrochemical workstation. When performing the hydrogen evolution linear voltammetry curve test, the potential scan range relative to the Hg / HgO electrode was -0.5 to -1.8 V, and the scan rate was 10 mVs. -1 The hydrogen evolution chronopotentiometry test was carried out at a current density of 10 mA cm -2 and 100mA cm -2 under the conditions of d. NiMoS / NF ternary composite electrode is used as the working electrode for hydrogen evolution reaction. When the current density is 10 mA cm -2 When the current density is 100 mA cm -2 The hydrogen evolution overpotential is 247 mV. The hydrogen evolution chronopotentiometry test was carried out at current densities of 10 mA cm -2 and 100mA cm-2 The overpotential showed no obvious attenuation after 50 h, and the potential fluctuation range was less than ±5 mV.
[0037] The following are several examples formulated according to the overall implementation scheme of a Ni-based non-precious metal hydrogen evolution electrocatalyst and preparation method of the present invention.
[0038] Among them, the contents of Examples 2 and 3 are similar to those of Example 1, and Example 1 is now taken as an example for detailed description.
[0039] Example 1 Pretreatment of nickel foam: Cut a 2×2 cm piece of nickel foam into a 50 mL beaker. Add 20 mL of 1 M HCl solution and sonicate for 10 minutes. Pour out the HCl and rinse with deionized water. Add anhydrous ethanol and sonicate for 10 minutes. Pour out the ethanol and rinse with deionized water. Finally, rinse with deionized water and sonicate for 15 minutes. After sonication, remove the nickel foam and vacuum dry it at 60°C for 6 hours.
[0040] Preparation of electrodeposition solution: Weigh 39.43 g NiSO4·6H2O, 7.25 g Na2MoO4·2H2O, 4.57 g CH4N2S, 1.86 gH3BO3, 28.09 g C6H5Na3O7·3H2O, and 8.77 g NaCl in a 500 mL beaker, add 300 mL of deionized water, and stir for 5 min to accelerate the dissolution of the reagents. Then, ultrasonicate for 15 min to evenly disperse the reagents.
[0041] Preparation of NiMoS / NF electrode by segmented electrodeposition: The prepared mixed solution was poured into a sealed electrolytic cell. A two-electrode system was used, with the cathode being the treated nickel foam and the anode being the titanium plate. Under a constant temperature of 45 °C, current was applied in four stages: the first stage: 10 mA cm -2 Deposition 600 s; second stage: 25 mA cm -2 Deposition time 900 s; third stage: 40 mA cm -2 Deposition time: 1200 s; Stage 4: 60 mA cm -2 Deposition was performed for 300 s. Each stage was separated by 5 min. After electrodeposition, the electrode was removed and the loose surface deposits were rinsed with deionized water. After standing in deionized water for 10 min, it was removed and thoroughly dried in a vacuum drying oven at 60°C to obtain a NiMoS / NF electrode.
[0042] Characterization of NiMoS / NF electrode: The product obtained in Example 1 was subjected to morphological analysis. The results are as follows: Figure 1 As shown in the figure, the NiMoS coating is agglomerated into cluster structures of varying sizes with irregular particles, and secondary small particles are further accumulated on the surface of the clusters to form abundant pores and a rough interface with uneven surfaces.
[0043] The element mapping analysis of Example 1 was performed using a scanning electron microscope (SEM-Mapping). The results are as follows: Figure 2 The obtained spectrum shows that the Mo, Ni, and S elements are evenly distributed on the surface of the cluster. This mapping further proves that the material is a NiMoS / NF composite material.
[0044] Example 2 The steps for preparing the porous NiMoS / NF ternary composite electrode by segmented electrodeposition in this embodiment are as follows: Pretreatment of nickel foam: same as in Example 1; Preparation of electrodeposition solution: 39.43 g NiSO4·6H2O, 14.52 g Na2MoO4·2H2O, 4.57 g CH4N2S, 1.86 g H3BO3, 28.09 g C6H5Na3O7·3H2O, and 8.77 g NaCl were weighed in a 500 mL beaker, 300 mL deionized water was added, and ultrasonication was performed for 15 min to accelerate the dissolution of the reagents, followed by stirring for 5 min to ensure uniform dispersion of the reagents.
[0045] Preparation of NiMoS / NF electrode by segmented electrodeposition: same as in Example 1.
[0046] Example 3 The steps for preparing the porous NiMoS / NF ternary composite electrode by segmented electrodeposition in this embodiment are as follows: Pretreatment of nickel foam: same as in Example 1; Preparation of electrodeposition solution: 39.43 g NiSO4·6H2O, 7.25 g Na2MoO4·2H2O, 6.85 g CH4N2S, 1.86 g H3BO3, 28.09 g C6H5Na3O7·3H2O, and 8.77 g NaCl were weighed in a 500 mL beaker, 300 mL deionized water was added, and ultrasonication was performed for 15 min to accelerate the dissolution of the reagents, followed by stirring for 5 min to ensure uniform dispersion of the reagents.
[0047] Preparation of NiMoS / NF electrode by segmented electrodeposition: same as in Example 1.
[0048] Example 4 The steps for preparing the porous NiMoS / NF electrode by segmented electrodeposition in this embodiment are as follows: Pretreatment of nickel foam: same as in Example 1; Preparation of electrodeposition solution: 39.43 g NiSO4·6H2O, 7.25 g Na2MoO4·2H2O, 2.28 g CH4N2S, 1.86 g H3BO3, 28.09 g C6H5Na3O7·3H2O, and 8.77 g NaCl were weighed in a 500 mL beaker, 300 mL deionized water was added, and ultrasonication was performed for 15 min to accelerate the dissolution of the reagents, followed by stirring for 5 min to ensure uniform dispersion of the reagents.
[0049] Preparation of NiMoS / NF electrode by segmented electrodeposition: same as in Example 1.
[0050] Application Example 1 An application of a NiMoS / NF composite material as an electrode material for hydrogen and oxygen evolution reactions is as follows: The instruments used in the following tests were all DH7001B electrochemical workstations, manufactured by Shanghai Donghua Instrument Co., Ltd.
[0051] The following tests all adopted a three-electrode system, wherein the electrode prepared in Example 1 was used as the working electrode (1×1.5 cm); a platinum sheet electrode was used as the counter electrode, and a Hg / HgO electrode was used as the reference electrode; and a 1 M KOH solution was used as the electrolyte.
[0052] Linear sweep cyclic voltammetry (LSV) test At 10 mV s -1 The linear scanning cyclic voltammetry curve of the electrode prepared in Example 1 was obtained as follows: Figure 3 As shown in the figure, the potential range of the curve is 0~-0.5 V (relative to standard hydrogen potential). The LSV diagram shows that when the potential is in the range of 0~0.5 V, the current density at the corresponding point of the curve increases sharply, and at 10 mA cm -2 At a current density of 100 mA cm, the overpotential is only 53 mV. -2 At a current density of 1.5 Å, the overpotential is only 247 mV. This phenomenon indicates that the prepared NiMoS / NF composite material has excellent electrocatalytic hydrogen evolution performance.
[0053] Chronopotentiometry (CP) test The hydrogen evolution stability diagram of the Ni-Mo-S ternary composite catalytic material electrode grown in situ on nickel foam was obtained by chronoamperometry, as shown in Figure 2. Figure 4 At 10 mA cm -2 and 100mA cm -2 At current densities of 100 and 200 nm, the hydrogen evolution performance of the material was stable after running for 25 h, the overpotential had no obvious attenuation, and the potential fluctuation range was less than ±5 mV.
[0054] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.
Claims
1. A Ni-based non-precious metal hydrogen evolution electrocatalyst, characterized in that The invention comprises a nickel foam substrate and a Ni-Mo-S ternary composite catalytic material deposition layer deposited on the nickel foam substrate; the Ni-Mo-S ternary composite catalytic material deposition layer presents a porous and rough cluster morphology, and the catalyst has hydrogen evolution activity under alkaline conditions.
2. A Ni-based non-precious metal hydrogen evolution electrocatalyst according to claim 1, characterized in that: The Ni-Mo-S ternary composite catalytic material deposition layer is agglomerated into cluster structures of varying sizes with irregular particles, and secondary small particles are accumulated on the surface of the clusters to form abundant pores and a rough interface with uneven contours.
3. A method for preparing a Ni-based non-precious metal hydrogen evolution electrocatalyst, characterized in that: The Ni-Mo-S ternary composite catalytic material is constructed by in-situ electrodeposition using a pretreated nickel foam as a substrate through gradient segmented current. The gradient segmented current in-situ electrodeposition includes several different deposition stages, and by setting different current densities between the deposition stages, a porous cluster structure of the Ni-Mo-S ternary composite catalytic material deposition layer is formed.
4. The method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to claim 3, characterized in that: The current density of the several different deposition stages is increased sequentially, and by controlling the electrodeposition time of the different deposition stages, the ratio optimization of Ni, Mo, and S and the optimization of the cluster structure in the Ni-Mo-S ternary composite catalytic material deposition layer are achieved.
5. The method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to claim 3, characterized in that: The following steps are involved: a. Substrate pretreatment: The nickel foam substrate was ultrasonically cleaned in HCl, ethanol and deionized water for 10 min each, and then dried for later use; b. Preparation of electrodeposition solution: The pretreated nickel foam obtained in step a was used as a cathode to prepare an electrodeposition solution containing NiSO4·6H2O, Na2MoO4·2H2O, CH4N2S, while adding H3BO3, trisodium citrate trihydrate and NaCl, and adjusting the solution pH to 4.0 with HCl; c. Staged electrodeposition: Using the pretreated nickel foam as the cathode, four stages of electrodeposition were performed sequentially at a constant temperature. After deposition, the surface residue was immediately removed by washing with deionized water and dried to obtain the final catalyst.
6. The method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to claim 5, characterized in that: In the preparation of the electrodeposition solution in step b, the HCl concentration is 1~3 M, the NiSO4•6H2O concentration is 0.5 M, the Na2MoO4•2H2O concentration is 0.1~0.3 M, the CH4N2S concentration is 0.1~0.3 M, the H3BO3 concentration is 0.1 M, the trisodium citrate trihydrate concentration is 0.1~0.3 M, and the NaCl concentration is 0.5 M.
7. The method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to claim 5, characterized in that: In the staged electrodeposition of step c, the electrodeposition adopts a two-electrode system, and the counter electrode is a titanium plate; the current density of the four stages of electrodeposition is 10, 25, 40, and 60 mA cm -2 , and the corresponding electrodeposition durations are 10, 15, 20, and 5 minutes, respectively.
8. The method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to claim 5, characterized in that: The molar ratio of Ni, Mo and S is 5:(1~3):(1~3).
9. The method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to claim 1, characterized in that: In the preparation of the electrodeposition solution in step b, the pH is adjusted using 1.0 M HCl solution, and the final pH value of the electrolyte is stabilized at 4.0; in step c, the electrolyte temperature is maintained at 45° C. by a constant temperature water bath system.
10. A Ni-based non-noble metal hydrogen evolution electrocatalyst according to any one of claims 1-2, or a catalyst prepared by the method for preparing a Ni-based non-noble metal hydrogen evolution electrocatalyst according to any one of claims 3-9, characterized in that: The catalyst serves as a hydrogen evolution reaction (HER) electrode in an alkaline water electrolysis system.