Process for the preparation of catalysts for the catalytic hydrolysis of boron-containing solid hydrogen storage materials

Abstract

This invention relates to the field of hydrogen storage materials technology, and more particularly to a method for preparing a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials. The method for preparing the catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials includes: providing a material containing a metal or alloy as a substrate material; depositing a transition metal element onto the substrate material to form a composite metal material; oxidizing the composite metal material; activating the oxidized composite metal material by immersing it in an aqueous solution of a boron-containing reducing agent; and washing the activated composite metal material to obtain the catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials. This invention improves the catalytic activity of the catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials.

Description

Technical Field

[0001] This application relates to the field of hydrogen storage materials technology, and in particular to a method for preparing a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials. Background Technology

[0002] Boron-containing solid hydrogen storage materials have attracted much attention in the field of hydrogen energy storage due to their high hydrogen storage density, relatively light weight, and high thermal stability. For example, ammonia borane is currently the chemical hydrogen storage material with the highest hydrogen content, making it an ideal chemical hydrogen storage material. Hydrogen in boron-containing solid hydrogen storage materials is mainly released through three methods: thermal decomposition, alcoholysis, and hydrolysis. Among these, hydrolysis has the advantages of relatively low cost, no need for heating, and stable and controllable reaction.

[0003] To efficiently catalyze the hydrolysis of boron-containing solid hydrogen storage materials, improving the catalytic activity of catalysts used to catalyze these materials remains a pressing issue in this field. Summary of the Invention

[0004] One object of the present invention is to improve the catalytic activity of catalysts used for the hydrolysis of boron-containing solid hydrogen storage materials.

[0005] Specifically, embodiments of this application provide a method for preparing a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials, comprising:

[0006] Provide a material containing a metal or alloy as the base material;

[0007] Transition metal elements are deposited onto the substrate material to form a composite metal material;

[0008] The composite metal material is subjected to oxidation treatment;

[0009] The oxidized composite metal material is placed in an aqueous solution containing a boron reducing agent for activation treatment;

[0010] The activated composite metal material is washed to obtain a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials.

[0011] Optionally, the step of depositing transition metal elements onto the substrate material to form a composite metal material includes:

[0012] Prepare an aqueous solution of a predetermined concentration, wherein the solute includes transition metal elements, as the electrolyte;

[0013] The substrate material is placed in the electrolyte as a working electrode for electrodeposition to form the composite metal material.

[0014] Optionally, the aqueous solution containing transition metal elements may be an aqueous solution with Co(NO3)2, Ni(NO3)2, or Fe(NO3)2 as the solute.

[0015] Optionally, the preset concentration is any value between 0.01 mol / L and 2 mol / L.

[0016] Alternatively, the electrodeposition time can be any value between 15 and 120 minutes.

[0017] Optionally, the voltage applied for electrodeposition is any value from -1V to -1.5V.

[0018] Optionally, after the step of depositing transition metal elements onto the substrate material to form a composite metal material, the method further includes:

[0019] The composite metal material was washed multiple times with water and ethanol, and then dried in a forced-air drying oven.

[0020] Optionally, the substrate material is a foam material with a metal or alloy skeleton.

[0021] Optionally, after the step of providing a material containing a metal or alloy as a base material, the method further includes:

[0022] The foam material is washed multiple times in ethanol, acetone and hydrochloric acid, and then dried at any temperature between 40-60°C for any time between 8-24 hours.

[0023] Optionally, the step of oxidizing the composite metal material includes:

[0024] The composite metal material is oxidized using air or oxygen, and the oxidation treatment temperature is any temperature between 200 and 1000°C.

[0025] According to a first aspect of the present invention, a catalyst is obtained by depositing a transition metal element on a substrate of a metal or alloy material to form a composite metal material, and then subjecting the composite metal material to oxidation treatment, activation treatment and washing in sequence. Due to the synergistic effect of the two metal elements in the catalyst, the catalytic activity can be greatly improved.

[0026] Furthermore, the catalytic activity of the prepared catalyst can be altered by controlling the amount of transition metal elements deposited on the metal or alloy substrate. Within a certain range, the greater the amount of transition metal elements deposited, the better the catalytic activity of the prepared catalyst. Moreover, by setting an appropriate deposition time, the catalyst can achieve optimal catalytic activity.

[0027] According to a second aspect of the present invention, an inexpensive foam material is used, which is treated by electrodeposition, followed by oxidation and reduction in a reducing agent solution containing boron. Through these three simple steps, a catalyst with good stability and excellent performance for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials is obtained. This makes the preparation process very simple and low-cost, and can be mass-produced.

[0028] Furthermore, since the foam material substrate has a relatively high specific surface area, it can play a role in dispersing and stabilizing active centers. By selecting a suitable foam material as the substrate, and appropriate electrolyte, reducing agent, and oxidation conditions, the catalytic activity and stability of the catalyst can be further improved, achieving an activity per unit area of ​​75.4 mL / (min·cm²). 2 It can still maintain more than 87% of its catalytic activity after 10 hours of catalysis.

[0029] According to a third aspect of the invention, a catalyst with optimal catalytic performance can be obtained by selecting a suitable combination of elements in the substrate material and the deposition material. Attached Figure Description

[0030] Figure 1 A flowchart of a method for preparing a catalyst for catalytic hydrolysis of boron-containing solid hydrogen storage materials according to an embodiment of the present invention is shown;

[0031] Figure 2 Catalytic activity curves of B-Cu Foam and B-CoCu Foam catalysts according to an embodiment of the present invention are shown;

[0032] Figure 3 Catalytic activity curves of B-CoCu Foam catalysts with different Co deposition amounts according to an embodiment of the present invention are shown;

[0033] Figure 4 A scanning electron microscope image of B-CoCu Foam 800, a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention, is shown.

[0034] Figure 5 Another scanning electron microscope image of catalyst B-CoCu Foam 800 for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention is shown;

[0035] Figure 6 A high-resolution transmission electron microscope image of B-CoCu Foam 800 catalyst for catalytic hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention is shown.

[0036] Figure 7The XRD pattern of catalyst B-CoCu Foam 800 for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention is shown.

[0037] Figure 8 The synchrotron X-ray absorption spectrum of the catalyst B-CoCu Foam 800 for catalytic hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention is shown.

[0038] Figure 9 A demonstration diagram of the hydrolysis of boron-containing solid hydrogen storage materials catalyzed by the B-CoCu Foam 800 catalyst according to Embodiment 1 of the present invention is shown.

[0039] Figure 10 The test curves for hydrogen production by the B-CoCu Foam 800 catalyst according to Example 1 of the present invention are shown.

[0040] Figure 11 The catalytic hydrogen production curves of the B-CoCu Foam 800 catalyst according to Example 1 of the present invention are shown after continuous catalysis for 0, 2, 4, 6, 8, and 10 hours.

[0041] Figure 12 The area catalytic activity of the B-CoCu Foam 800 catalyst according to Example 1 of the present invention after being cut into different sizes is shown;

[0042] Figure 13 The in-situ synchrotron X-ray absorption spectrum of the B-CoCu Foam 800 catalyst according to Embodiment 1 of the present invention is shown.

[0043] Figure 14 Hydrogen production curves of B-CoCu Foam, B-CoCu Foam 200, B-CoCu Foam 400, B-CoCu Foam 600 and B-CoCu Foam 800 catalysts according to embodiments of the present invention are shown.

[0044] Figure 15 The XRD patterns of cobalt copper foam oxidized at 0°C, 200°C, 400°C, 600°C, 800°C and 1000°C respectively, according to an embodiment of the present invention are shown.

[0045] Figure 16 A comparative graph showing the catalytic activity curves of catalysts obtained using nickel foam, copper foam, and zinc foam as foam materials according to embodiments of the present invention is provided.

[0046] Figure 17 A comparative graph showing the catalytic activity curves of catalysts obtained by electrodepositing metallic nickel, metallic iron and metallic cobalt on copper foam according to embodiments of the present invention is shown. Detailed Implementation

[0047] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0048] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0049] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0050] Figure 1 A flowchart illustrating a method for preparing a catalyst for the hydrolysis of boron-containing solid hydrogen storage materials according to an embodiment of the present invention is shown. Figure 1 As shown, in one embodiment, the preparation method of the catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials includes:

[0051] Step S100: Provide a material containing metal or alloy as a base material;

[0052] Step S200: Transition metal elements are deposited onto the substrate material to form a composite metal material;

[0053] Step S300: Oxidize the composite metal material;

[0054] Step S400: The oxidized composite metal material is placed in an aqueous solution containing boron reducing agent for activation treatment;

[0055] Step S500: The activated composite metal material is washed to obtain a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials.

[0056] In step S100, the material of the metal or alloy is not particularly limited. The metal can be, for example, iron, cobalt, nickel, platinum, gold, rhodium, ruthenium, copper, or titanium. More preferably, the metal is selected as iron, cobalt, nickel, copper, or titanium. The alloy can be, for example, NiFe alloy, NiCo alloy, FeCu alloy, CuCo alloy, NiCu alloy, or FeCo alloy. More preferably, the alloy is selected as NiFe alloy, NiCo alloy, or FeCo alloy. In a preferred embodiment, the base material is a foam material with a metal or alloy skeleton.

[0057] In step S200, transition metal elements can be deposited onto the substrate material using common deposition methods, such as electrodeposition, chemical vapor deposition, and physical vapor deposition. Transition metals can be, for example, iron, cobalt, nickel, copper, zinc, titanium, chromium, manganese, molybdenum, ruthenium, or rhodium. In one embodiment, transition metal elements are deposited by electrodeposition. First, an aqueous solution of a predetermined concentration containing the transition metal element as the solute is prepared as the electrolyte. Then, the substrate material is placed in the electrolyte as the working electrode for electrodeposition to form a composite metal material. The aqueous solution can be a chloride, sulfate, acetate, etc. In one embodiment, the aqueous solution containing the transition metal element is selected from Co(NO3)2, Ni(NO3)2, or Fe(NO3)2 as the solute. The predetermined concentration is 0.01 mol / L, 0.1 mol / L, 0.5 mol / L, 1 mol / L, or 2 mol / L, or any other value between 0.01 mol / L and 2 mol / L. The electrodeposition time is 15 minutes, 30 minutes, 60 minutes, or 120 minutes, or any other value between 15 and 120 minutes. The voltage applied for electrodeposition is -1V, -1.1V, -1.3V, or -1.5V, or any other value between -1V and -1.5V.

[0058] In step S300, the oxidation process is carried out in air or oxygen at a temperature of 200°C, 400°C, 600°C, 800°C, or 1000°C, or any other temperature between 200°C and 1000°C. The oxidation time is 2 hours, 4 hours, 6 hours, 8 hours, or 10 hours, or any other time value between 2 and 10 hours. Preferably, the oxidation temperature is 700°C or 900°C, or any other temperature between 700°C and 900°C. More preferably, the oxidation temperature is 800°C. At this temperature, the foamed metal can be completely oxidized to a metal oxide, thereby introducing a sufficient number of defects.

[0059] In step S400, the boron-containing reducing agent can be, for example, sodium borohydride, potassium borohydride, rubidium borohydride, ammonium tetrahydroborate, ammonia borane, or lithium borohydride. More preferably, the boron-containing reducing agent is selected from sodium borohydride, ammonia borane, or lithium borohydride. It is essential to ensure that the reducing agent is in excess.

[0060] In step S500, the material is washed multiple times with deionized water to remove byproducts from the surface of the activated foam material. After washing, a drying process can be performed. The drying temperature can be, for example, 40°C, 50°C, or 60°C, or any other temperature between 40°C and 60°C. The drying time can be, for example, 8 hours, 10 hours, 102 hours, 15 hours, 20 hours, or 24 hours, or any other value between 8 hours and 24 hours.

[0061] To investigate the influence of the substrate on the catalytic activity of the catalyst, the inventors conducted the following experiment: Copper foam (as a comparative example) and Copper foam deposited with Co were subjected to oxidation and activation treatments under the same conditions. The activation treatment was a reduction treatment using a boron-containing reducing agent. The resulting products were labeled as B-Cu Foam and B-CoCu Foam, respectively. B-Cu Foam and B-CoCu Foam were then placed in an aqueous solution of boron-containing solid hydrogen storage material to produce hydrogen. Figure 2 Catalytic activity curves of B-Cu Foam and B-CoCu Foam catalysts according to an embodiment of the present invention are shown. Figure 2 As shown, compared to the single-metal catalyst B-Cu Foam, the catalyst B-CoCu Foam with deposited Co element exhibits significantly improved catalytic performance. It can catalyze the release of 201 ml of hydrogen gas from 3 mol of ammonia borane in less than 3 minutes, demonstrating a rapid catalytic rate. This is due to Cu's excellent electrical conductivity, enabling rapid charge conduction. Furthermore, Cu adsorbs and activates H2O molecules in the solution during the catalytic hydrolysis of ammonia borane, enriching the catalyst surface with OH- (hydroxyl ions). These OH- ions enriched on the substrate can effectively attack the BN bonds that have been activated by the CoB bonds. Figure 2 The B-Cu Foam in the sample could only catalyze the release of 13 ml of hydrogen from 3 mol of ammonia borane after 6 minutes, indicating that although the copper foam substrate itself exhibits poor catalytic activity for the hydrolysis of ammonia borane, the synergistic effect between Co and Cu can significantly improve the catalytic performance of the catalyst.

[0062] To investigate the effect of different Co deposition amounts on catalytic activity, the inventors also conducted the following experiment, changing the Co deposition time in the above experiment and setting the deposition time to 0, 15 min, 30 min, 60 min and 120 min respectively. Figure 3Catalytic activity curves of B-CoCu Foam catalysts with different Co deposition amounts according to an embodiment of the present invention are shown. Figure 3 As shown, the B-Cu foam without Co deposition exhibits almost no catalytic activity. However, the catalytic activity gradually increases with increasing deposition time, demonstrating the positive effect of Co on enhancing catalytic activity. When the deposition time reaches 30 min, the catalytic rate increases with the increase of the main active sites, Co-B. However, when excessive Co-B bonds completely cover the Cu substrate, the catalytic substrate cannot contact the internal Cu, resulting in the loss of the synergistic effect between Co and Cu, and a gradual decrease in catalytic performance. This also proves that the synergistic effect between Co and Cu is an important factor in improving catalytic performance.

[0063] In this embodiment, transition metal elements are deposited on a metal or alloy substrate. Therefore, the catalyst prepared has the highest proportion of transition metal elements on the surface. As the thickness increases, the proportion of transition metal elements may gradually decrease, while the content of metal or alloy on the substrate material gradually increases. Of course, a certain amount of metal or alloy on the substrate material may also exist on the catalyst surface. This elemental distribution pattern is highly conducive to the efficient catalytic process. During catalysis, transition metals typically possess more complex electronic structures and more d electrons, allowing them to participate in the catalytic process with a greater number of electrons. In the substrate activation phase, the high content of transition metals enables rapid activation of the substrate. As the reaction time increases, the reaction of the catalyst surface gradually exposes the internal materials, increasing the proportion of metals or alloys on the substrate material. Therefore, at least two metal elements participate in the catalytic reaction, facilitating efficient product precipitation. Especially when a highly conductive metal element is used on the substrate, it can rapidly conduct charge, activating H2O molecules in the solution and enriching OH- ions on the catalyst surface. These OH- ions enriched on the substrate can effectively attack the BN bonds activated by the bond between the transition metal and boron. Composite metal elements can further enhance the formation of highly stable catalysts. Therefore, the preparation method of depositing transition metal elements on the substrate material can create catalysts particularly beneficial for the hydrolysis of boron-containing solid hydrogen storage materials. Furthermore, the total amount of deposited transition metals affects the rate of catalysis. This is because a larger amount of deposited transition metals accelerates the activation of the substrate at the beginning of the catalytic reaction, while excessive deposits hinder the sustained and efficient catalysis in the later stages of the reaction. Therefore, by setting the deposition conditions, the proportion and total amount of transition metal elements at different thicknesses can be predetermined, resulting in highly active catalysts and optimal synergistic effects between the substrate material and the deposited transition metal elements.

[0064] In this embodiment, transition metal elements are deposited on a metal or alloy substrate to form a composite metal material with a specific ratio distribution. The composite metal material is then subjected to oxidation, activation and washing treatments in sequence to obtain a catalyst. Due to the synergistic effect of the two metal elements in the catalyst, the catalytic activity can be greatly improved.

[0065] Furthermore, the catalytic activity of the prepared catalyst can be altered by controlling the amount of transition metal elements deposited on the metal or alloy substrate. Within a certain range, the greater the amount of transition metal elements deposited, the better the catalytic activity of the prepared catalyst. Moreover, by setting an appropriate deposition time, the catalyst can achieve optimal catalytic activity.

[0066] In a further embodiment, the substrate material is a foam material with a metal or alloy skeleton, and the following steps are included after step S100:

[0067] The foam material is washed multiple times with ethanol, acetone, and hydrochloric acid, for example, 3 or 5 times, and then dried at any temperature between 40-60°C for any time between 8-24 hours. For example, the drying temperature can be 40°C, 50°C, or 60°C, and the drying time can be 8 hours, 10 hours, 12 hours, 15 hours, 20 hours, or 24 hours. Washing removes residual impurities from the surface of the foam material, and drying removes the washing solvent.

[0068] In a further embodiment, step S200 is followed by the following step:

[0069] The composite metal material was washed multiple times with water and ethanol, and then dried in a forced-air drying oven.

[0070] Example 1

[0071] The preparation method of the catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials includes the following steps:

[0072] 1) The commercially available copper foam was washed three times each in ethanol, acetone and hydrochloric acid to remove residual impurities on the surface, and then dried in a vacuum drying oven at 50°C for 12 hours to remove the washing solvent.

[0073] 2) Prepare a 1 mol / L cobalt nitrate aqueous solution as the electrolyte, a graphite rod as the counter electrode, and Ag / AgCl as the reference electrode. Use cleaned copper foam as the working electrode to form a three-electrode electrodeposition tank. Then, apply a voltage of -1.1V to the electrodeposition tank and deposit for 30 minutes. After deposition, wash the sample several times with water and ethanol, and dry it in a forced-air drying oven for further processing.

[0074] 3) The electrodeposited foam material is placed in air (or oxygen) at 800°C for 7 hours to undergo oxidation treatment (the oxidized cobalt copper foam is marked as CoCuO Foam 800).

[0075] 4) The oxidized cobalt-copper foam was immersed in an aqueous solution containing 3M ammonia borane and 0.5M NaOH for reduction treatment to obtain reduced oxidized cobalt-copper foam;

[0076] 5) The reduced copper oxide foam was washed several times with deionized water to remove the byproducts on the surface, and then dried in a vacuum drying oven at 50°C for 12 hours to obtain the final product (labeled as B-CoCu Foam 800).

[0077] Figure 4 A scanning electron microscope image of B-CoCu Foam 800, a catalyst for the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention, is shown. Figure 4 It can be seen that the surface of B-CoCu Foam800 has a rough porous structure.

[0078] Figure 5 Another scanning electron microscope image of B-CoCu Foam 800, a catalyst for the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention, is shown. Figure 5 It can be seen that the copper foam is loaded with a large number of amorphous cobalt nanoclusters.

[0079] Figure 6 A high-resolution transmission electron microscope image of B-CoCu Foam 800, a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention, is shown. Figure 7 The XRD pattern of catalyst B-CoCu Foam 800 for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention is shown. Figure 8 The synchrotron X-ray absorption spectrum of B-CoCu Foam 800, a catalyst for catalytic hydrolysis of boron-containing solid hydrogen storage materials according to Embodiment 1 of the present invention, is shown.

[0080] Depend on Figure 7 It can be seen that the diffraction peak of B-CoCu Foam 800 corresponds to elemental copper, combined with... Figure 6 It can be inferred that the nanoparticles on the B-CoCuFoam surface are amorphous. (From...) Figure 8 It can be seen that the valence state of B-CoCu Foam 800 is basically consistent with that of the standard sample of pure copper. Figures 6 to 8 Various characterization data confirm that the composition of B-CoCu Foam 800 is reduced copper and amorphous cobalt supported on it.

[0081] Figure 9 A demonstration diagram showing the hydrolysis of boron-containing solid hydrogen storage materials catalyzed by the B-CoCu Foam 800 catalyst according to Embodiment 1 of the present invention is shown. Figure 9 It can be seen that hydrogen gas is rapidly generated after the catalyst is inserted into the boron-containing solid hydrogen storage material solution, and the reaction stops immediately after the catalyst is removed.

[0082] Figure 10 The catalytic hydrogen production test curve of the B-CoCu Foam 800 catalyst according to Example 1 of the present invention is shown. Figure 10 It can be seen that B-CoCu Foam 800 can catalyze the release of 201 mL of hydrogen gas from 3 mol of boron-containing solid hydrogen storage material in less than 3 minutes, with a unit area activity of 75.4 mL / (min·cm). 2 This demonstrates that the B-CoCu Foam 800 catalyst exhibits excellent catalytic activity.

[0083] Figure 11 The catalytic hydrogen production curves of the B-CoCu Foam 800 catalyst according to Example 1 of the present invention are shown after continuous catalysis for 0, 2, 4, 6, 8, and 10 hours. Figure 11 It can be seen that after 10 hours of stability testing, the catalyst still did not show a significant performance decline.

[0084] Figure 12 The area catalytic activity of the B-CoCu Foam 800 catalyst according to Example 1 of the present invention is shown after being cut into different sizes. The results show that size does not affect the catalytic activity per unit area, which means that B-CoCuFoam 800 can be scaled up proportionally to achieve large-scale preparation.

[0085] Figure 13 The in-situ synchrotron X-ray absorption spectrum of the B-CoCu Foam 800 catalyst according to Example 1 of the present invention is shown. To further illustrate the effect of the reduction process on catalytic performance, the electronic structure during the catalytic process was studied using in-situ synchrotron X-ray absorption spectroscopy (see [link to synchrotron X-ray absorption spectrum]). Figure 13The study found that when B-CoCu Foam 800 was in a boron-containing solid hydrogen storage material solution, an increase in the edge-front peak and a decrease in the white line peak were observed. The spectral shape was consistent with the XANES of cobalt borides at the Co K-edge reported in the literature, indicating that some surface oxides reconstructed Co-B bonds during the catalytic hydrolysis of the boron-containing solid hydrogen storage material. After the reaction, a decrease in the edge-front peak and an increase in the white line peak were observed, indicating that the surface of B-CoCu Foam 800 was quickly oxidized again after the catalytic reaction. Therefore, this suggests that the Co-B bond is an intermediate that exists only during the catalytic process, which is beneficial for lowering the activation energy of the entire catalytic process and improving the overall catalytic activity. Since the catalytic active sites are dynamically generated during the catalytic process, the problem of decreased catalytic activity due to the reduction of active sites by the boron-containing solid hydrogen storage material during catalysis is avoided.

[0086] This embodiment utilizes inexpensive foam material, which is treated by electrodeposition, followed by oxidation and reduction in a boron-containing reducing agent solution. Through these three simple steps, a catalyst with good stability and excellent performance for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials is obtained. This makes the preparation process very simple, low-cost, and suitable for large-scale mass production.

[0087] Furthermore, since the foam material substrate has a relatively high specific surface area, it can play a role in dispersing and stabilizing active centers. By selecting a suitable foam material as the substrate, and appropriate electrolyte, reducing agent, and oxidation conditions, the catalytic activity and stability of the catalyst can be further improved, achieving an activity per unit area of ​​75.4 mL / (min·cm²). 2 It can still maintain more than 87% of its catalytic activity after 10 hours of catalysis.

[0088] Example 2:

[0089] The difference between Example 2 and Example 1 is that the oxidation temperature in this example is selected as 200℃, 400℃, 600℃, or 800℃. To compare the catalytic performance of the catalysts formed at different oxidation temperatures, in addition to testing the catalytic activity of the catalysts obtained at all the above temperatures, the catalytic activity of the catalyst obtained at 25℃ (i.e., the catalyst obtained without oxidation treatment) was also tested. The resulting catalysts were labeled as B-CoCu Foam, B-CoCu Foam 200, B-CoCu Foam 400, and B-CoCu Foam 600, respectively (the number after B-CoCu Foam indicates the oxidation temperature).

[0090] Figure 14Hydrogen production curves for B-CoCu Foam, B-CoCu Foam 200, B-CoCu Foam 400, B-CoCu Foam 600 and B-CoCu Foam 800 catalysts according to embodiments of the present invention are shown. Figure 15 XRD patterns of cobalt-copper foam oxidized at 0°C, 200°C, 400°C, 600°C, 800°C, and 1000°C, respectively, according to embodiments of the present invention, are shown. Figure 14 It can be seen that the catalytic activity of copper-cobalt foam reduced directly with ammonia borane without oxidation treatment is much lower than that of foamed copper-cobalt foam that has undergone oxidation treatment. For example... Figure 15 As shown, when the oxidation temperature reaches 600℃, XRD shows that the performance is improved after Cu in the bulk phase is completely converted into CuO, and the performance reaches its maximum when the temperature reaches 800℃.

[0091] Example 3:

[0092] The difference between Example 3 and Example 1 is that the foam material used is either nickel foam or zinc foam. To investigate the catalytic effect of electrodeposited metallic cobalt on boron-containing solid hydrogen storage materials using different foam materials, the catalytic activities of nickel foam and cobalt-zinc foam were tested.

[0093] Figure 16 A comparative graph of catalytic activity curves for catalysts obtained using copper foam, nickel foam, and zinc foam as foam materials according to embodiments of the present invention is shown. The catalysts obtained using nickel foam, copper foam, and zinc foam as foam materials are labeled as B-CoNi Foam, B-CoCu Foam, and B-CoZn Foam, respectively. Figure 16 It can be seen that B-CoNi Foam, B-CoCu Foam and B-CoZn Foam all have good catalytic activity for the hydrolysis of boron-containing solid hydrogen storage materials. Among them, B-CoCuFoam has the best catalytic performance, indicating that selecting appropriate substrate materials and deposition materials can further improve catalytic performance.

[0094] Example 4:

[0095] The difference between Example 4 and Example 1 is that the metal electrodeposited on the copper foam is either nickel or iron. To investigate the catalytic effects of different metals electrodeposited on boron-containing solid hydrogen storage materials, the catalytic activities of nickel-copper foam and iron-copper foam were tested.

[0096] Figure 17A comparative graph showing the catalytic activity curves of catalysts obtained by electrodepositing metallic nickel, metallic iron, and metallic cobalt on copper foam according to embodiments of the present invention is presented. The catalysts obtained by electrodepositing metallic nickel, metallic iron, and metallic cobalt on copper foam are labeled as B-NiCu Foam, B-FeCu Foam, and B-CoCu Foam, respectively. Figure 17 It can be seen that B-NiCuFoam, B-FeCu Foam and B-CoCu Foam all have good catalytic activity for the hydrolysis of boron-containing solid hydrogen storage materials.

[0097] As can be seen from the data in Examples 3 and 4, a catalyst with the best catalytic performance can be obtained by selecting a suitable combination of elements in the substrate material and the deposition material.

[0098] In one embodiment of the present invention, a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials, prepared by the preparation method in any of the above embodiments, is also provided.

[0099] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for the preparation of a catalyst for the catalysis of the hydrolysis of a boron-containing solid hydrogen storage material, characterized in that, include: Provide a material containing a metal or alloy as the base material; Transition metal elements are deposited onto the substrate material to form a composite metal material; The composite metal material is subjected to oxidation treatment; The oxidized composite metal material is placed in an aqueous solution containing a boron reducing agent for activation treatment; The activated composite metal material is washed to obtain a catalyst for catalyzing the hydrolysis of boron-containing solid hydrogen storage materials. The step of depositing transition metal elements onto the substrate material to form a composite metal material includes: Prepare an aqueous solution of a predetermined concentration, wherein the solute includes transition metal elements, as the electrolyte; The substrate material is placed in the electrolyte as a working electrode for electrodeposition to form the composite metal material; For aqueous solutions containing transition metal elements, the aqueous solution with Co(NO3)2 as the solute is selected. The preset concentration is any value between 0.01 mol / L and 2 mol / L; The electrodeposition time is any value between 15 and 120 minutes; The voltage applied during electrodeposition is any value between -1V and -1.5V; The substrate material is a foam material with copper or an alloy as the skeleton, and the alloy is FeCu alloy, CuCo alloy or NiCu alloy.

2. The preparation method according to claim 1, characterized in that, The step of depositing transition metal elements onto the substrate material to form a composite metal material further includes: The composite metal material was washed multiple times with water and ethanol, and then dried in a forced-air drying oven.

3. The preparation method according to claim 1, characterized in that, The step of providing a material containing a metal or alloy as a base material further includes: The foam material is washed multiple times in ethanol, acetone and hydrochloric acid, and then dried at any temperature between 40-60°C for any time between 8-24 hours.

4. The preparation method according to any one of claims 1-3, characterized in that, The step of oxidizing the composite metal material includes oxidizing the composite metal material using air or oxygen, and the oxidation treatment temperature is any temperature between 200-1000℃.

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