A three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material and its preparation method

Abstract

The present invention relates to a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material, the preparation method of which comprises the following steps: preparing ordered mesoporous silica, introducing a nickel source into the ordered mesoporous channels thereof, and calcining to obtain nickel oxide / ordered mesoporous silica; weighing a phosphorus source and nickel oxide / ordered mesoporous silica in proportion, calcining to fully phosphate the nickel oxide / ordered mesoporous silica, and performing a passivation treatment to obtain nickel phosphide / ordered mesoporous silica; etching the nickel phosphide / ordered mesoporous silica with an excess of hydrofluoric acid, washing and drying after sufficient reaction, to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material. The present invention designs a hydrogen evolution electrocatalyst material with excellent performance by introducing an ordered mesoporous structure. The internal channels of the ordered structure are bicontinuous and orderly interconnected, the mesoporous surface is rich in catalytic active sites, the specific surface area is relatively large, and the hydrogen evolution catalytic activity of the nickel phosphide is improved. The material has good application prospects in hydrogen energy development and application.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalytic materials and catalysts, relates to the preparation technology of electrocatalytic materials, and specifically relates to a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material and a preparation method thereof. Background Art

[0002] In recent years, with the increasing consumption of fossil energy, environmental pollution has become increasingly prominent, forcing researchers to conduct in-depth research and development on alternative, clean, and sustainable renewable energy sources. Sustainable production in an environmentally friendly manner is crucial. Hydrogen is considered a promising renewable clean energy source due to its high energy density and zero emissions during combustion. Current hydrogen production processes mainly rely on steam reforming, coal gasification, and oxidation hydrogen production technologies. These processes not only emit environmentally unfriendly gases but also increase fossil fuel consumption. Water electrolysis, as a green, environmentally friendly, and sustainable hydrogen production method, can electrolyze water driven by renewable green energy (including solar energy, wind energy, or electricity), alleviating the problem of fossil fuel consumption and even completely eliminating dependence on fossil fuels, promoting the adjustment and transformation of the energy structure. Therefore, the water electrolysis hydrogen evolution reaction (HER) is expected to become one of the most effective hydrogen production processes and has received widespread attention. Currently, platinum-group noble metal-based catalysts are widely considered the most efficient catalysts for hydrogen production from water electrolysis. However, factors such as low storage availability and high cost limit their potential use. Therefore, there is an urgent need to identify and develop efficient and low-cost alternatives to platinum-group noble metal catalysts. Currently, transition metals (TMs), which are low-cost, abundant, and mechanically stable, are considered to be a candidate for replacing platinum-group metals.

[0003] In the research and development of transition metal catalytic materials, most transition metal-based catalysts face the problem of poor electron conductivity, which hinders the transmission of electrons within them, thereby inhibiting the catalytic activity of the materials. However, transition metal phosphides (TMPs) have special electronic properties and have high electron transport performance and catalytic activity in acidic media. Therefore, Ni2P, as an efficient HER electrocatalyst, is expected to become a substitute for platinum group precious metals. Researchers have prepared nickel phosphide electrocatalytic materials with various morphologies to make them have high catalytic activity and stability. However, most nano nickel phosphide electrocatalytic materials usually have disordered structures, relatively small specific surface areas, limited electron transport channels and catalytic active sites; and the hydrogen generated by the active sites on the catalyst surface cannot be released in time, so that some active sites cannot be fully utilized, resulting in a decrease in its hydrogen evolution activity. Summary of the Invention

[0004] The present invention aims to solve the above-mentioned problems existing in the prior art and proposes a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material and a preparation method thereof. By adopting different synthetic strategies to change its morphology and structure, the structure of the electrocatalytic material is designed and optimized to expose more active sites. At the same time, the hydrogen generated on the surface of the active sites is released in a timely manner and fully utilized. The electrolyte is fully in contact with the active sites on the surface of the electrocatalyst to increase the solid / liquid interface, promote the transfer of electrons and shorten the electron transmission channel, thereby improving its electrocatalytic hydrogen evolution activity.

[0005] The technical solution of the present invention is:

[0006] The present invention provides a method for preparing a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material, comprising the following steps:

[0007] (1) preparing ordered mesoporous silica, slowly introducing a nickel source dissolved in an ethanol solution into the ordered mesoporous channels of the prepared ordered mesoporous silica by a solvent evaporation method, and then calcining at 530-570° C. in a nitrogen atmosphere for 2.5-3.5 hours to obtain nickel oxide / ordered mesoporous silica;

[0008] (2) weighing a phosphorus source and the nickel oxide / ordered mesoporous silica prepared in step (1) at an element molar ratio of P:Ni=(12-18):1, calcining them at a certain distance in a nitrogen atmosphere, setting a temperature ramp to raise the calcination temperature to 330-370°C, calcining at this temperature for 2.5-3.5 hours to fully phosphate the nickel oxide / ordered mesoporous silica, and cooling them to room temperature in a nitrogen environment after the phosphating treatment, and then introducing 10% vol O2 / N2 inert gas for passivation treatment to obtain nickel phosphide / ordered mesoporous silica;

[0009] (3) etching the nickel phosphide / ordered mesoporous silica prepared in step (2) with excess hydrofluoric acid, wherein the mass ratio of nickel phosphide / ordered mesoporous silica to hydrofluoric acid is 1:(17-34), stirring and reacting at room temperature, washing to neutrality, and drying to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

[0010] Furthermore, the ordered mesoporous silica includes KIT-6, SBA-15 and SBA-16.

[0011] Furthermore, the nickel source is any one or more of nickel nitrate hexahydrate, nickel acetate tetrahydrate, and nickel chloride hexahydrate.

[0012] Furthermore, the phosphorus source is sodium hypophosphite monohydrate.

[0013] Furthermore, the preparation of ordered mesoporous silica in step (1) comprises the following steps:

[0014] First, P123 and concentrated hydrochloric acid are added to deionized water in sequence and stirred at room temperature until a homogeneous solution is obtained; then, n-butanol and tetraethyl orthosilicate are added to the homogeneous solution in sequence and stirring is continued; the homogeneous solution obtained by stirring is transferred to a reactor, sealed and placed in an oven, and reacted at 90-120°C for 22-26 hours; after the reaction is completed, the reaction is cooled to room temperature; the reaction product is washed with deionized water and anhydrous ethanol, dried at 55-65°C for 5.5-6.5 hours, and the product is collected; the collected product is placed in anhydrous ethanol and concentrated hydrochloric acid, stirred at room temperature for 2 hours, then washed several times with deionized water and anhydrous ethanol, dried at 55-65°C for 11-13 hours, and the dried product is calcined at 450-550°C for 2.5-3.5 hours to obtain ordered mesoporous silica.

[0015] Furthermore, the specific operation of the solvent evaporation method in step (1) is: first dissolving the nickel source in ethanol, then adding ordered mesoporous silica, wherein the mass ratio of the nickel source to the ordered mesoporous silica is (0.8-1.6):1, stirring at room temperature until the solvent is evaporated to dryness, after the ethanol solvent is evaporated to dryness, adding dry n-hexane, and stirring at room temperature until the solvent is evaporated to dryness.

[0016] Preferably, nickel nitrate hexahydrate is dissolved in ethanol, and then ordered mesoporous silica is added, the mass ratio of nickel nitrate hexahydrate to ordered mesoporous silica is 1.2:1, and the mixture is stirred at room temperature until the ethanol solvent is evaporated, and then dry n-hexane is added, and the mixture is stirred at room temperature until the n-hexane solvent is evaporated.

[0017] Furthermore, in the step (2), the nickel oxide / ordered mesoporous silica precursor material and sodium hypophosphite monohydrate are placed in two porcelain boats according to the element molar ratio P:Ni=15:1, and calcined under the protection of a nitrogen atmosphere; the two porcelain boats are placed in the center of the tubular furnace, and the porcelain boat containing sodium hypophosphite monohydrate is placed on the side close to the nitrogen inlet, and the porcelain boat containing the nickel oxide / ordered mesoporous silica precursor is placed on the side close to the outlet.

[0018] Furthermore, the heating program in step (2) is to first increase the furnace temperature by 0.5-3°C·min under nitrogen protection. -1 The heating rate is increased from room temperature to 90-150°C and maintained at this temperature for 1-4 hours to evaporate the crystal water in sodium hypophosphite monohydrate; then the temperature is heated to 330-370°C at the same heating rate and calcined at this temperature for 2.5-3.5 hours; the gas flow rate during the entire heating process is 25 mL min -1 .

[0019] Specifically, the heating program can be: under nitrogen protection, the furnace temperature is first increased by 2°C·min -1The heating rate was increased from room temperature to 120°C and maintained at this temperature for 2 h. This process evaporates the crystal water in sodium hypophosphite monohydrate. Then, it was heated to 350°C at the same heating rate and calcined at this temperature for 3 h. The gas flow rate during the entire heating process was 25 mL min -1 .

[0020] Furthermore, in the step (3), the phosphated nickel phosphide / ordered mesoporous silica is added to excess hydrofluoric acid in a mass ratio of nickel phosphide / ordered mesoporous silica to hydrofluoric acid of 1:20, and then stirred at room temperature for 12 hours to fully react, and the silica template is etched. After that, it is washed with deionized water to neutrality, and then rinsed with anhydrous ethanol, and then placed in a vacuum drying oven at 55-65° C. and vacuum dried for 5.5-6.5 hours to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

[0021] The present invention also provides a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared by the above preparation method.

[0022] The present invention uses cubic Ia 3d symmetric ordered mesoporous silica as a template, nickel nitrate and other materials as nickel sources, and successfully prepares ordered mesoporous nickel phosphide (OM-Ni2P) by nanocasting method; the synthesized OM-Ni2P catalyst perfectly repeats the highly symmetrical mesoporous structure of ordered mesoporous silica and exhibits a large amount of active Ni species Ni δ+ and active substance P δ- The ordered mesoporous structure not only promotes the transfer of electrons, but also promotes the diffusion of reaction media; the OM-Ni2P catalyst has good hydrogen evolution electrocatalytic performance and has an ordered mesoporous structure.

[0023] Beneficial effects of the present invention:

[0024] (1) The present invention designs a hydrogen evolution electrocatalyst material with excellent performance by introducing an ordered mesoporous structure. The prepared three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material has bicontinuous and orderly interconnected internal pores in its ordered structure, abundant catalytic active sites on the mesoporous surface, excellent hydrogen evolution performance, and a relatively large specific surface area, thereby improving the hydrogen evolution catalytic activity of nickel phosphide. The prepared three-dimensional ordered mesoporous nickel phosphide electrode material has good application prospects in the development and application of hydrogen energy.

[0025] (2) The present invention effectively solves the problems of few active sites on the surface of hydrogen evolution catalyst materials, small solid / liquid interface on the electrode surface, and large resistance of electron transmission channels. Through the ordered mesoporous structure of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material, more active sites are highly exposed, and the efficient transmission of electrons and ions is promoted, thereby improving the electrical conductivity and electron transmission performance, and preparing a catalyst material with low overpotential, low mass transfer resistance, high active surface area and high stability.

[0026] (3) In the preparation method of the present invention, a nickel source dissolved in an ethanol solution is first slowly introduced into the ordered mesoporous channels of the prepared ordered mesoporous silica template by a solvent evaporation method, and calcined under a nitrogen atmosphere to obtain a nickel oxide / ordered mesoporous silica composite material; then, sodium hypophosphite monohydrate is used as a phosphorus source to phosphate the sample; finally, the ordered mesoporous silica is etched with an excess of hydrofluoric acid to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material; the preparation method is simple in process, low in cost, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The small-angle XRD diffraction patterns of the ordered mesoporous silica KIT-6 and the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1;

[0028] Figure 2 Wide-angle XRD diffraction patterns of the nickel phosphide / ordered mesoporous silica KIT-6 precursor material and the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1;

[0029] Figure 3 This is a scanning electron microscope image of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1;

[0030] Figure 4 are transmission electron microscopy morphology images; wherein, (a), (b), and (c) are transmission electron microscopy morphology images of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1; (d) is a transmission electron microscopy morphology image of the disordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Comparative Example 1;

[0031] Figure 5 Cathodic linear scan polarization curves of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1 and the disordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Comparative Example 1;

[0032] Figure 6 These are Tafel slope curves of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1 and the disordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Comparative Example 1. DETAILED DESCRIPTION

[0033] To further understand the present invention, the following will further clearly and completely illustrate and describe the technical solutions of the present invention in conjunction with the accompanying drawings and embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0034] The present invention provides a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material, the preparation method of which comprises the following steps:

[0035] (1) Weigh the raw materials according to the molar ratio of P123: tetraethyl orthosilicate: concentrated hydrochloric acid: water: n-butanol = (0.015-0.0209): (0.75-1.35): (1.5-1.9): (153-193): (1.25-1.66), add P123 and concentrated hydrochloric acid to a beaker containing deionized water, place it on a magnetic stirrer, and stir at room temperature until a homogeneous solution is obtained; then add n-butanol and tetraethyl orthosilicate to the beaker in turn. The mixture was placed on a magnetic stirrer and stirred until a homogeneous solution was obtained. The homogeneous solution obtained by stirring was transferred to a stainless steel reactor lined with polytetrafluoroethylene. The sealed reactor was placed in an oven at 90-120°C for reaction for 22-26 hours. After the reaction was completed, the reactor was cooled to room temperature. The sample was taken out of the reactor, washed with deionized water and anhydrous ethanol, and then dried in a blast drying oven at 55-65°C for 5.5-6.5 hours to collect the sample.

[0036] The collected samples are placed in a beaker containing anhydrous ethanol and concentrated hydrochloric acid, placed on a magnetic stirrer, and stirred at room temperature to extract as much P123 surfactant as possible; then washed several times with deionized water and anhydrous ethanol, placed in a vacuum drying oven, and dried at 55-65°C for 11-13 hours, and then the samples are collected. In order to fully remove the polymer template P123 and recover it, the collected samples are placed in a muffle furnace and calcined at 450-550°C for 2.5-3.5 hours to obtain ordered mesoporous silica, including ordered mesoporous silica KIT-6, SBA-15 and SBA-16.

[0037] (2) In order to fully impregnate the nickel source into the ordered pores of the ordered mesoporous silica, the ordered mesoporous silica obtained in step (1) and the nickel source (one or more of nickel nitrate hexahydrate, nickel acetate tetrahydrate, and nickel chloride hexahydrate) are sequentially added to a beaker containing ethanol in a mass ratio of nickel source to ordered mesoporous silica (0.8-1.6):1, and the mixture is placed on a magnetic stirrer in a fume hood and stirred at room temperature until the solvent evaporates; after the ethanol solvent evaporates, the mixture is added to a beaker containing dry n-hexane and stirred at room temperature until the solvent evaporates;

[0038] The sample obtained above was then placed in a tube furnace, slowly heated to a calcination temperature of 530-570° C. under a nitrogen atmosphere, and calcined at this temperature for 2.5-3.5 hours to obtain the target product, named nickel oxide / ordered mesoporous silica.

[0039] (3) The nickel oxide / ordered mesoporous silica precursor material prepared in step (2) and sodium hypophosphite monohydrate are placed in two porcelain boats according to the element molar ratio P:Ni=(12-18):1 (preferably 15:1), and then the two porcelain boats containing the samples are placed in the center of the tube furnace, and the porcelain boat containing the sodium hypophosphite monohydrate is placed on the side close to the nitrogen inlet of the quartz tube; the two porcelain boats containing the samples are separated by a certain distance to fully utilize the phosphorus source to phosphate the nickel oxide / ordered mesoporous silica precursor;

[0040] In the above steps, a porcelain boat containing sodium hypophosphite monohydrate as a phosphorus source is placed on the side close to the nitrogen inlet of the quartz tube, and a porcelain boat containing nickel oxide / ordered mesoporous silica precursor is placed on the side of the outlet. Under the protection of a nitrogen atmosphere, sodium hypophosphite monohydrate first evaporates the crystallization water inside the sample, and then thermally decomposes it to produce phosphine, which can fully diffuse in the internal pores along with the nitrogen flow, thereby fully phosphating the nickel oxide to produce nickel phosphide.

[0041] After connecting the gas line, connect the outlet of the tube furnace to a mechanical pump and perform a vacuum treatment process to a negative pressure (the pressure gauge at the air inlet of the tube furnace is -0.1 MPa). Evacuate the air in the tube furnace and the gas pipeline. Then, turn on the nitrogen bottle switch knob and the pressure reducing valve, and then open the air inlet valve of the tube furnace to allow nitrogen to slowly enter the quartz tube of the tube furnace. When the pressure gauge at the air inlet of the tube furnace is stable at 0 MPa, open the air outlet valve of the tube furnace at the same time. Then, turn on the heating switch of the tube furnace, set the heating program, and under the protection of nitrogen, first increase the furnace temperature by 0.5-3℃·min. -1 The heating rate is increased from room temperature to 90-150°C and maintained at this temperature for 1-4 hours to evaporate the crystal water in sodium hypophosphite monohydrate; then the temperature is heated to 330-370°C at the same heating rate and calcined at this temperature for 2.5-3.5 hours; the gas flow rate during the entire heating process is 25 mL min -1 , nickel oxide / ordered mesoporous silica is phosphated to generate nickel phosphide / ordered mesoporous silica composite material;

[0042] After the phosphating treatment is completed, nitrogen is still kept flowing into the tube furnace. The furnace temperature is naturally cooled to room temperature under nitrogen protection. Subsequently, 10% vol O2 / N2 inert gas is introduced for passivation treatment at a gas flow rate of 20 mL min -1Finally, the nickel oxide / ordered mesoporous silica after phosphating treatment was taken out from the tube furnace and named as nickel phosphide / ordered mesoporous silica composite material.

[0043] (4) The material after phosphating in step (3) is placed in a polytetrafluoroethylene liner filled with hydrofluoric acid, wherein the ratio of nickel phosphide / ordered mesoporous silica to hydrofluoric acid is 1:(17-34), and is placed on a magnetic stirrer and stirred at room temperature for 12 hours to fully react and etch the silica template. It is then washed with deionized water until neutral, and then rinsed with anhydrous ethanol, and then placed in a vacuum drying oven at 55-65°C for 5.5-6.5 hours to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

[0044] Example 1

[0045] In this example, an OM-Ni2P catalyst for hydrogen electrolysis having an ordered mesoporous structure was prepared by a nanocasting method using ordered mesoporous silica KIT-6 with cubic Ia 3d symmetry as a template. The preparation process includes: first, using Ni(NO3)2·6H2O as a nickel source, slowly introducing Ni(NO3)2·6H2O dissolved in an ethanol solution into the ordered mesoporous channels of the KIT-6 template by solvent evaporation, and calcining at 550°C in an N2 atmosphere for 3 hours to obtain a NiO / KIT-6 composite material; then, using NaH2PO2·H2O as a phosphorus source, phosphating the sample at 350°C for 3 hours; and finally, etching the KIT-6 with excess HF to obtain ordered mesoporous OM-Ni2P.

[0046] The specific preparation steps are as follows:

[0047] Step 1: Add 10.0 g of P123 and 16.7 mL of concentrated hydrochloric acid to a beaker containing 282.5 mL of deionized water, place on a magnetic stirrer, and stir at room temperature until a homogeneous solution is obtained.

[0048] Step 2: 10.0 g of n-butanol and 21.5 g of tetraethyl orthosilicate were added to the homogeneous solution obtained in step 1, and the mixture was stirred on a magnetic stirrer for 24 h.

[0049] Step 3: The homogeneous solution obtained by stirring in step 2 was transferred to a stainless steel reactor lined with polytetrafluoroethylene, and then the sealed reactor was placed in an oven at 110°C for 24 hours. After the reaction was completed, it was cooled to room temperature, and the sample was taken out of the reactor, washed with deionized water and anhydrous ethanol, and then dried at 60°C for 6 hours to collect the sample;

[0050] Step 4: Place the sample obtained in step 3 in a beaker containing 350 mL of anhydrous ethanol and 25 mL of concentrated hydrochloric acid, place it on a magnetic stirrer, and stir at room temperature for 2 h. In order to extract as much P123 as possible, wash it several times with deionized water and anhydrous ethanol, and dry it in vacuum at 60°C overnight to obtain a sample;

[0051] Step 5: Place the sample obtained in step 4 in a muffle furnace and calcine at 500° C. for 3 h to fully remove the polymer template P123 to obtain ordered mesoporous silica KIT-6;

[0052] Step 6: 5.0 g of ordered mesoporous silica KIT-6 and 6.0 g of nickel nitrate hexahydrate obtained in step 5 were added to a beaker containing 150 mL of ethanol, placed on a magnetic stirrer in a fume hood, and stirred at room temperature until the solvent evaporated;

[0053] Step 7: After the ethanol solvent in step 6 evaporates, add it to a beaker containing 100 mL of dry n-hexane and stir at room temperature until the solvent evaporates to dryness, so as to allow as much nickel nitrate hexahydrate as possible to be impregnated into the ordered mesopores of the ordered mesoporous silica KIT-6;

[0054] Step 8: Place the sample obtained in step 7 in a tube furnace, slowly heat it to 550° C. under a nitrogen atmosphere, and calcine it at this temperature for 3 hours to obtain the target product, named nickel oxide / ordered mesoporous silica KIT-6;

[0055] Step 9: Place 0.3 g of the nickel oxide / ordered mesoporous silica KIT-6 precursor material prepared in step 8 and 6.39 g of sodium hypophosphite monohydrate (element molar ratio P:Ni = 15:1) in two porcelain boats, respectively. Then, place the two porcelain boats containing the samples in the center of the tube furnace with a certain distance between them, and place the porcelain boat containing sodium hypophosphite monohydrate on the side close to the nitrogen inlet of the quartz tube.

[0056] Step 10. After connecting the gas line, connect the outlet of the tube furnace to a mechanical pump to evacuate the air to a negative pressure. Evacuate the air in the tube furnace and the gas line. The pressure gauge at the air inlet of the tube furnace is -0.1 MPa. Then, turn on the switch knob of the nitrogen bottle and the pressure reducing valve, and then open the air inlet valve of the tube furnace to allow nitrogen to slowly enter the quartz tube of the tube furnace. When the pressure gauge at the air inlet of the tube furnace is stable at 0 MPa, open the air outlet valve of the tube furnace at the same time. Then, turn on the heating switch of the tube furnace. Under the protection of nitrogen, the furnace temperature is first increased by 2°C·min. -1 The heating rate was increased from room temperature to 120°C and maintained at this temperature for 2 h. This process evaporated the crystal water in the sodium hypophosphite monohydrate. Then, it was heated to 350°C at the same heating rate and calcined at this temperature for 3 h. The gas flow rate during the entire heating process was 25 mL min -1, so that nickel oxide / ordered mesoporous silica KIT-6 is fully phosphated;

[0057] Step 11: After the phosphating treatment in step 10 is completed, nitrogen is still kept flowing into the tube furnace. The furnace temperature is naturally cooled to room temperature under nitrogen protection. Subsequently, 10% vol O2 / N2 inert gas is introduced for passivation treatment at a gas flow rate of 20 mL min -1 Finally, the nickel oxide / ordered mesoporous silica KIT-6 after phosphating treatment was taken out from the tube furnace and named nickel phosphide / ordered mesoporous silica KIT-6 composite material;

[0058] Step 12: Place the material phosphated in step 11 into a polytetrafluoroethylene liner containing hydrofluoric acid, with the ratio of nickel phosphide / ordered mesoporous silica KIT-6 to hydrofluoric acid being 1:20. Place it on a magnetic stirrer and stir it at room temperature for 12 hours. In order to fully etch the ordered mesoporous silica KIT-6, wash it with deionized water until it is neutral, then rinse it with anhydrous ethanol, and then vacuum dry it at 60°C for 6 hours to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

[0059] Example 2

[0060] The specific preparation steps are as follows:

[0061] Step 1: Add 9.2 g of P123 and 15.6 mL of concentrated hydrochloric acid to a beaker containing 312.0 mL of deionized water, place on a magnetic stirrer, and stir at room temperature until a homogeneous solution is obtained;

[0062] Step 2: 9.8 g of n-butanol and 25.5 g of tetraethyl orthosilicate were added to the homogeneous solution obtained in step 1, and the mixture was stirred on a magnetic stirrer for 24 h.

[0063] Step 3: The homogeneous solution obtained by stirring in step 2 was transferred to a stainless steel reactor lined with polytetrafluoroethylene, and then the sealed reactor was placed in an oven at 90°C for 26 hours. After the reaction was completed, it was cooled to room temperature, and the sample was taken out of the reactor, washed with deionized water and anhydrous ethanol, and then dried at 55°C for 6.5 hours to collect the sample;

[0064] Step 4: Place the sample obtained in step 3 in a beaker containing 320 mL of anhydrous ethanol and 22 mL of concentrated hydrochloric acid, place it on a magnetic stirrer, and stir at room temperature for 2 h. In order to extract as much P123 as possible, wash it several times with deionized water and anhydrous ethanol, and vacuum dry it at 55°C for 13 h to obtain a sample;

[0065] Step 5: Place the sample obtained in step 4 in a muffle furnace and calcine at 450° C. for 3.5 h to fully remove the polymer template P123 to obtain ordered mesoporous silica KIT-6;

[0066] Step 6: 5.0 g of ordered mesoporous silica KIT-6 and 5.0 g of nickel acetate tetrahydrate obtained in step 5 were added to a beaker containing 150 mL of ethanol, placed on a magnetic stirrer in a fume hood, and stirred at room temperature until the solvent evaporated;

[0067] Step 7: After the ethanol solvent in step 6 evaporates, add it to a beaker containing 110 mL of dry n-hexane and stir at room temperature until the solvent evaporates to dryness, so as to allow as much nickel nitrate hexahydrate as possible to be impregnated into the ordered mesopores of the ordered mesoporous silica KIT-6;

[0068] Step 8: Place the sample obtained in step 7 in a tube furnace, slowly heat to 530° C. under a nitrogen atmosphere, and calcine at this temperature for 3.5 hours to obtain the target product, named nickel oxide / ordered mesoporous silica KIT-6;

[0069] Step 9: Place 0.3 g of the nickel oxide / ordered mesoporous silica KIT-6 precursor material prepared in step 8 and 5.11 g of sodium hypophosphite monohydrate (element molar ratio P:Ni = 12:1) in two porcelain boats, respectively. Then, place the two porcelain boats containing the samples in the center of the tube furnace with a certain distance between them, and place the porcelain boat containing sodium hypophosphite monohydrate on the side close to the nitrogen inlet of the quartz tube.

[0070] Step 10. After connecting the gas line, connect the outlet of the tube furnace to a mechanical pump to evacuate the air to a negative pressure. Evacuate the air in the tube furnace and the gas line. The pressure gauge at the air inlet of the tube furnace is -0.1 MPa. Then, turn on the switch knob of the nitrogen bottle and the pressure reducing valve, and then open the air inlet valve of the tube furnace to allow nitrogen to slowly enter the quartz tube of the tube furnace. When the pressure gauge at the air inlet of the tube furnace is stable at 0 MPa, open the air outlet valve of the tube furnace at the same time. Then, turn on the heating switch of the tube furnace. Under the protection of nitrogen, the furnace temperature is first increased by 0.5℃·min. -1 The temperature was raised from room temperature to 130°C and maintained at this temperature for 4 h. This process evaporated the crystal water in the sodium hypophosphite monohydrate. Then, the temperature was raised to 330°C at the same rate and calcined at this temperature for 3.5 h. The gas flow rate during the entire heating process was 25 mL min. -1 , so that nickel oxide / ordered mesoporous silica KIT-6 is fully phosphated;

[0071] Step 11: After the phosphating treatment in step 10 is completed, nitrogen is still kept flowing into the tube furnace. The furnace temperature is naturally cooled to room temperature under nitrogen protection. Subsequently, 10% vol O2 / N2 inert gas is introduced for passivation treatment at a gas flow rate of 20 mL min -1Finally, the nickel oxide / ordered mesoporous silica KIT-6 after phosphating treatment was taken out from the tube furnace and named nickel phosphide / ordered mesoporous silica KIT-6 composite material;

[0072] Step 12: Place the material phosphated in step 11 into a polytetrafluoroethylene liner containing hydrofluoric acid, with the ratio of nickel phosphide / ordered mesoporous silica KIT-6 to hydrofluoric acid being 1:17. Place it on a magnetic stirrer and stir it at room temperature for 12 hours. In order to fully etch the ordered mesoporous silica KIT-6, wash it with deionized water until it is neutral, then rinse it with anhydrous ethanol, and then vacuum dry it at 55°C for 6.5 hours to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

[0073] Example 3

[0074] The specific preparation steps are as follows:

[0075] Step 1: Add 11.2 g of P123 and 16.8 mL of concentrated hydrochloric acid to a beaker containing 298.5 mL of deionized water, place on a magnetic stirrer, and stir at room temperature until a homogeneous solution is obtained.

[0076] Step 2: 11.2 g of n-butanol and 28.0 g of tetraethyl orthosilicate were added to the homogeneous solution obtained in step 1, and the mixture was stirred on a magnetic stirrer for 24 h.

[0077] Step 3: The homogeneous solution obtained by stirring in step 2 was transferred to a stainless steel reactor lined with polytetrafluoroethylene, and the sealed reactor was placed in an oven at 120°C for 22 hours. After the reaction was completed, it was cooled to room temperature. The sample was taken out of the reactor, washed with deionized water and anhydrous ethanol, and then dried at 65°C for 5.5 hours to collect the sample;

[0078] Step 4: Place the sample obtained in step 3 in a beaker containing 360 mL of anhydrous ethanol and 26 mL of concentrated hydrochloric acid, place it on a magnetic stirrer, and stir at room temperature for 2 h. In order to extract as much P123 as possible, wash it several times with deionized water and anhydrous ethanol, and vacuum dry it at 65°C for 11 h to obtain a sample;

[0079] Step 5: Place the sample obtained in step 4 in a muffle furnace and calcine at 550° C. for 2.5 h to fully remove the polymer template P123 to obtain ordered mesoporous silica KIT-6;

[0080] Step 6: 5.0 g of ordered mesoporous silica KIT-6 and 5.5 g of nickel chloride hexahydrate obtained in step 5 were added to a beaker containing 150 mL of ethanol, placed on a magnetic stirrer in a fume hood, and stirred at room temperature until the solvent evaporated;

[0081] Step 7: After the ethanol solvent in step 6 evaporates, add it to a beaker containing 120 mL of dry n-hexane and stir at room temperature until the solvent evaporates to dryness, so as to allow as much nickel nitrate hexahydrate as possible to be impregnated into the ordered mesopores of the ordered mesoporous silica KIT-6;

[0082] Step 8: Place the sample obtained in step 7 in a tube furnace, slowly heat it to 570° C. under a nitrogen atmosphere, and calcine it at this temperature for 2.5 hours to obtain the target product, named nickel oxide / ordered mesoporous silica KIT-6;

[0083] Step 9: Place 0.3 g of the nickel oxide / ordered mesoporous silica KIT-6 precursor material prepared in step 8 and 7.66 g of sodium hypophosphite monohydrate (element molar ratio P:Ni = 18:1) in two porcelain boats, respectively. Then, place the two porcelain boats containing the samples in the center of the tube furnace with a certain distance between them, and place the porcelain boat containing sodium hypophosphite monohydrate on the side close to the nitrogen inlet of the quartz tube.

[0084] Step 10. After connecting the gas line, connect the outlet of the tube furnace to a mechanical pump to evacuate the air to a negative pressure. Evacuate the air in the tube furnace and the gas line. The pressure gauge at the air inlet of the tube furnace is -0.1 MPa. Then, turn on the switch knob of the nitrogen bottle and the pressure reducing valve, and then open the air inlet valve of the tube furnace to allow nitrogen to slowly enter the quartz tube of the tube furnace. When the pressure gauge at the air inlet of the tube furnace is stable at 0 MPa, open the air outlet valve of the tube furnace at the same time. Then, turn on the heating switch of the tube furnace. Under the protection of nitrogen, the furnace temperature is first increased by 3°C / min. -1 The temperature was raised from room temperature to 150°C and maintained at this temperature for 1 hour to evaporate the crystal water in sodium hypophosphite monohydrate. The mixture was then heated to 370°C at the same heating rate and calcined at this temperature for 2.5 hours. The gas flow rate during the entire heating process was 25 mL min -1 , so that nickel oxide / ordered mesoporous silica KIT-6 is fully phosphated;

[0085] Step 11: After the phosphating treatment in step 10 is completed, nitrogen is still kept flowing into the tube furnace. The furnace temperature is naturally cooled to room temperature under nitrogen protection. Subsequently, 10% vol O2 / N2 inert gas is introduced for passivation treatment at a gas flow rate of 20 mL min -1 Finally, the nickel oxide / ordered mesoporous silica KIT-6 after phosphating treatment was taken out from the tube furnace and named nickel phosphide / ordered mesoporous silica KIT-6 composite material;

[0086] Step 12: Place the material phosphated in step 11 into a polytetrafluoroethylene liner containing hydrofluoric acid, with the ratio of nickel phosphide / ordered mesoporous silica KIT-6 to hydrofluoric acid being 1:34. Place it on a magnetic stirrer and stir it at room temperature for 12 hours. In order to fully etch the ordered mesoporous silica KIT-6, wash it with deionized water until it is neutral, then rinse it with anhydrous ethanol, and then vacuum dry it at 65°C for 5.5 hours to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

[0087] Comparative Example 1

[0088] Preparation of disordered mesoporous nickel phosphide catalyst

[0089] First, 3.05 g (NH4)2HPO4 was added to 30 mL deionized water and stirred until completely dissolved. Then, 3.36 g Ni(NO3)2·6H2O was added and stirred to dissolve. 2.43 g citric acid (CA) was added again, and finally the pH was adjusted to 2-3 with 0.5 M HNO3. After the mixed solution was stirred for 3 h, it was first placed in a 120 ° C oil bath to evaporate to dryness, and then placed in a 120 ° C oven to dry overnight to form a viscous and fluffy sample. Subsequently, the sample was heated in a muffle furnace at 1.5 ° C·min -1 The temperature was raised to 500°C and calcined at 500°C for 4 hours to obtain the semi-finished CA-NiO. The CA-NiO sample was ground and pressed into pellets (20-40 mesh) before being subjected to temperature-programmed reduction treatment. The temperature-programmed reduction treatment process was as follows: 1 mL of catalyst was loaded into the reaction tube, and the H2 flow rate was controlled at 160 mL min -1 , at 5℃·min -1 The heating rate was increased from room temperature to 300°C, and then to 1°C·min -1 The temperature was raised to 650°C, then kept constant at 650°C for 2.5 hours, and cooled to room temperature in a N2 atmosphere; subsequently, 10% vol O2 / N2 was introduced for passivation treatment; the resulting disordered mesoporous Ni2P material was named CA-Ni2P.

[0090] Test Example 1

[0091] The three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Example 1 was used as the working electrode, the silver / silver chloride electrode was used as the reference electrode, and the graphite rod was used as the counter electrode. All electrochemical measurements were performed on a Shanghai Chenhua CHI 760E electrochemical workstation. Before the electrochemical measurements, nitrogen was introduced into the acidic electrolyte (0.5M H2SO4) for 30 minutes for degassing, and all electrochemical measurements were performed at room temperature. Similarly, electrochemical measurements were performed using the CA-Ni2P material prepared in Comparative Example 1 as the working electrode.

[0092] The linear sweep voltammetry (LSV) test was performed to evaluate the hydrogen evolution performance of the three-dimensional ordered mesoporous nickel phosphide electrode in the potential window range of -0.696 to -0.096 V, with a scan rate of 5 mV·s -1 , LSV measurement values were corrected using 95% iR compensation. The Tafel slope was used to evaluate the activity of the catalyst. The Tafel curve was obtained by plotting the logarithmic curve of overpotential and current density. The Tafel curve part satisfied the Tafel formula: η=a+b*logj, where η is the overpotential, b is the Tafel slope, j is the current density, a is the intercept, and the scan rate is 5mV·s -1 All electrochemical tests were performed in 0.5MH2SO4 electrolyte, and all potentials were corrected to reversible hydrogen electrode potential (RHE) using the equation, E(RHE) = E(Ag / AgCl) + 0.205 + 0.059*PH.

[0093] like Figure 1 The small-angle XRD diffraction patterns of the ordered mesoporous silica KIT-6 and the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1 can be clearly observed from the small-angle XRD diffraction patterns. The samples have good crystallinity. The diffraction angles 2θ = 0.91° and 1.03° correspond to the (211) and (220) diffraction planes of the ordered mesoporous silica KIT-6, respectively. The weaker diffraction peaks between the diffraction angles 2θ = 1.40-1.66° are also attributed to the (321), (400), (420) and (332) crystal planes of the ordered mesoporous silica KIT-6, indicating that a bicontinuous cubic Ia 3d symmetry ordered mesoporous silica KIT-6 template has been successfully prepared. In the small-angle XRD diffraction spectrum of OM-Ni2P, the diffraction angle 2θ = 0.97 corresponds to the (211) crystal plane of ordered mesoporous silica, but the diffraction peak corresponding to the (211) crystal plane shifts slightly to a higher angle and the diffraction peak intensity decreases. This is because after nickel nitrate hexahydrate is used as a precursor to impregnate the mesoporous structure of the silica template, and after subsequent high-temperature phosphating treatment and template etching treatment, the skeleton structure of OM-Ni2P shrinks slightly and the pore size is slightly reduced.

[0094] like Figure 2The wide-angle XRD diffraction patterns of the nickel phosphide / ordered mesoporous silica precursor material and the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1 can be clearly observed from the wide-angle XRD diffraction pattern that the nickel phosphide has good crystallinity. The nickel phosphide / ordered mesoporous silica KIT-6 catalyst has a broad diffraction peak at a diffraction angle of 2θ≈15-30°, which belongs to the diffraction peak of amorphous silica; the diffraction angles 2θ=40.7°, 44.6°, 47.3°, 54.2°, 55.0° and 74.6° correspond to the (111), (201), (210), (300), (211) and (311) crystal planes of Ni2P, respectively, corresponding to the XRD standard card JCPDS, PDF#03-0953 of Ni2P. This indicates that the nickel oxide / ordered mesoporous silica KIT-6 material was successfully converted into a nickel oxide / ordered mesoporous silica KIT-6 material through in-situ phosphating. In this spectrum, the broad diffraction peak at diffraction angles 2θ≈15-30° disappears after 12 hours of hydrofluoric acid etching, demonstrating the successful preparation of a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalyst via nanocasting.

[0095] Figure 3 This is a scanning electron microscope image of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1. Figure 3 The nickel phosphide electrocatalytic material shown has a porous structure, and the ordered mesoporous skeleton arrangement of nickel phosphide can be observed, which also indicates that nickel phosphide with a three-dimensional ordered mesoporous structure is synthesized by nanocasting.

[0096] Figure 4 (a), (b), and (c) are transmission electron microscopy images and selected area electron diffraction (SAED) characterizations of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1. Figure 4 (a) and (b) Transmission electron micrographs of nickel phosphide electrocatalytic materials clearly show a highly ordered three-dimensional cubic bicontinuous mesoporous structure. The cubic Ia 3d mesoporous structure observed in each direction is very complete and highly ordered, indicating that almost all nickel nitrate hexahydrate as a precursor has been successfully impregnated into the mesopores of the ordered mesoporous silica KIT-6 template. Then, a three-dimensional ordered mesoporous nickel phosphide electrocatalytic material was successfully replicated from the highly dispersed cubic mesoporous silica KIT-6 template by nanocasting. Figure 4 (c) The spot pattern of selected area electron diffraction (SAED) of OM-Ni2P is combined with the (111), (201), (210) and (300) crystal phases of Ni2P, further indicating the formation of OM-Ni2P polycrystalline phase. Figure 4(d) is a transmission electron microscopy image of the disordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Comparative Example 1. The CA-Ni2P catalyst particles are disorderly distributed, and particles are locally accumulated.

[0097] Figure 5 The cathode linear scan polarization curves of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1 and the disordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Comparative Example 1 are shown in FIG. Figure 5 It can be observed that the electrochemical hydrogen evolution activity of OM-Ni2P is better than that of CA-Ni2P. -2 When , the overpotentials of OM-Ni2P and CA-Ni2P hydrogen evolution electrodes are 170mV and 279mV respectively. Compared with CA-Ni2P prepared in Comparative Example 1, the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1 has a smaller hydrogen evolution overpotential.

[0098] The difference in HER activity between OM-Ni2P and CA-Ni2P catalysts may be due to the following reasons. On the one hand, the catalytic activity of Ni2P is attributed to the electronic properties of Ni and P, and the mechanism of electrocatalytic hydrogen production is similar to that of hydrogenase. δ- As H + Acceptor, metal site Ni δ+ As an electron collector, the H + Gain electrons and form H2. At the same time, Li et al. showed that as long as its crystalline metallic properties remain unchanged, elements with higher electronegativity are conducive to the formation of H2 and promote water splitting activity. Compared with the disordered CA-Ni2P catalyst, the ordered mesoporous structure of OM-Ni2P can promote the full phosphating of NiO by the phosphorus source, resulting in a higher relative content of nickel phosphide. Therefore, the number of positively charged nickel and the number of negatively charged phosphorus in OM-Ni2P are greater than those in CA-Ni2P, which ensures the higher HER activity of the former. On the other hand, the ordered mesoporous structure is conducive to exposing more active sites, which is conducive to the transfer of charges and electrons. Moreover, this ordered mesoporous structure also makes it easy for the electrolyte to diffuse to the surface active sites of OM-Ni2P, accelerating the kinetics of the HER process, improving its electrocatalytic activity, and promoting the dissociation of water.

[0099] This suggests that the ordered mesoporous structure not only facilitates the thermal decomposition of phosphine by sodium hypophosphite monohydrate to fully phosphide the nickel oxide, but also exposes more active sites, enhancing its electrocatalytic activity and thus accelerating water decomposition. Therefore, the ordered mesoporous structure in the three-dimensional ordered mesoporous nickel phosphide electrocatalyst is beneficial for improving hydrogen evolution catalytic activity.

[0100] Figure 6The Tafel slope curves of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1 and the disordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared in Comparative Example 1 are shown in FIG. Figure 6 It can be observed that the Tafel slopes of the prepared OM-Ni2P and CA-Ni2P are 99 mV·dec -1 and 152.2mV·dec -1 , indicating that the OM-Ni2P electrode has a faster electrocatalytic hydrogen production efficiency. The Tafel slope of OM-Ni2P is 40~120mV·dec -1 interval, indicating that the electrocatalytic hydrogen evolution reaction process complies with the Volmer–Heyrovsky mechanism, which uses the electrochemical desorption process of hydrogen in the reaction path as the rate-determining step. This further proves that the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material (OM-Ni2P) prepared in Example 1 has the best hydrogen evolution performance. The good kinetic performance of the three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material may be derived from the fact that, on the one hand, the ordered mesoporous structure can promote full contact between the electrolyte and the active sites, shorten the diffusion path from the electrolyte to the catalyst surface, reduce the charge transfer resistance, and promote mass transfer and electron / proton transfer. On the other hand, a large number of ordered mesoporous channels act as transport channels, which not only promotes the H in the electrolyte + The contact reaction with the active sites also ensures the timely release of H2 bubbles formed on the surface of the active sites. This rapidly exposes the active sites of the catalyst, improving their utilization efficiency. These factors together accelerate the kinetics of the HER process on the OM-Ni2P electrode.

[0101] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, and modifications made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for preparing a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material, characterized in that: The following steps are involved: (1) preparing ordered mesoporous silica, slowly introducing a nickel source dissolved in an ethanol solution into the ordered mesoporous channels of the prepared ordered mesoporous silica by a solvent evaporation method, and then calcining at 530-570° C. in a nitrogen atmosphere for 2.5-3.5 hours to obtain nickel oxide / ordered mesoporous silica; The specific operation of the solvent evaporation method in step (1) is as follows: first dissolving a nickel source in ethanol, then adding ordered mesoporous silica, wherein the mass ratio of the nickel source to the ordered mesoporous silica is (0.8-1.6):1, stirring at room temperature until the solvent is evaporated to dryness, after the ethanol solvent is evaporated to dryness, adding dry n-hexane, and stirring at room temperature until the solvent is evaporated to dryness; (2) weighing a phosphorus source and the nickel oxide / ordered mesoporous silica prepared in step (1) at an element molar ratio of P:Ni=(12-18):1, calcining them at a certain distance in a nitrogen atmosphere, setting a temperature ramp to raise the calcination temperature to 330-370°C, calcining at this temperature for 2.5-3.5 hours to fully phosphate the nickel oxide / ordered mesoporous silica, and cooling them to room temperature in a nitrogen environment after the phosphating treatment, and then introducing 10% vol O2 / N2 inert gas for passivation treatment to obtain nickel phosphide / ordered mesoporous silica; (3) etching the nickel phosphide / ordered mesoporous silica prepared in step (2) with excess hydrofluoric acid, wherein the mass ratio of nickel phosphide / ordered mesoporous silica to hydrofluoric acid is 1:(17-34), stirring and reacting at room temperature, washing to neutrality, and drying to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material; The preparation of ordered mesoporous silica in step (1) comprises the following steps: First, P123 and concentrated hydrochloric acid are added to deionized water in sequence and stirred at room temperature until a homogeneous solution is obtained; then, n-butanol and tetraethyl orthosilicate are added to the homogeneous solution in sequence and stirring is continued; the homogeneous solution obtained by stirring is transferred to a reactor, sealed and placed in an oven, and reacted at 90-120°C for 22-26 hours; after the reaction is completed, the reaction is cooled to room temperature; the reaction product is washed with deionized water and anhydrous ethanol, dried at 55-65°C for 5.5-6.5 hours, and the product is collected; the collected product is placed in anhydrous ethanol and concentrated hydrochloric acid, stirred at room temperature for 2 hours, then washed several times with deionized water and anhydrous ethanol, dried at 55-65°C for 11-13 hours, and the dried product is calcined at 450-550°C for 2.5-3.5 hours to obtain ordered mesoporous silica.

2. The preparation method according to claim 1, characterized in that The ordered mesoporous silica includes KIT-6.

3. The preparation method according to claim 1, characterized in that The nickel source is any one or more of nickel nitrate hexahydrate, nickel acetate tetrahydrate, and nickel chloride hexahydrate.

4. The preparation method according to claim 1, characterized in that The phosphorus source is sodium hypophosphite monohydrate.

5. The preparation method according to claim 4, characterized in that In the step (2), the nickel oxide / ordered mesoporous silica precursor material and sodium hypophosphite monohydrate are placed in two porcelain boats according to the element molar ratio P:Ni=15:1, and calcined under the protection of a nitrogen atmosphere; the two porcelain boats are placed in the center of the tubular furnace, and the porcelain boat containing the sodium hypophosphite monohydrate is placed on the side close to the nitrogen inlet, and the porcelain boat containing the nickel oxide / ordered mesoporous silica precursor is placed on the side close to the outlet.

6. The preparation method according to claim 4, characterized in that The heating procedure in step (2) is to first increase the furnace temperature to 0.5-3°C·min under nitrogen protection. -1 The heating rate is increased from room temperature to 90-150°C and maintained at this temperature for 1-4 hours to evaporate the crystal water in sodium hypophosphite monohydrate; then the temperature is heated to 330-370°C at the same heating rate and calcined at this temperature for 2.5-3.5 hours; the gas flow rate during the entire heating process is 25 mL min -1 .

7. The preparation method according to claim 1, characterized in that In the step (3), the phosphated nickel phosphide / ordered mesoporous silica is added to excess hydrofluoric acid in a mass ratio of nickel phosphide / ordered mesoporous silica to hydrofluoric acid of 1:20, and then stirred at room temperature for 12 hours to fully react, and the silica template is etched. After that, the silica template is washed with deionized water until neutral, and then rinsed with anhydrous ethanol, and then placed in a vacuum drying oven at 55-65° C. and vacuum dried for 5.5-6.5 hours to obtain a three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material.

8. A three-dimensional ordered mesoporous nickel phosphide hydrogen evolution electrocatalytic material prepared by the preparation method according to any one of claims 1 to 7.

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