Composite hydrogen storage film and method for preparing the same
By introducing a composite hydrogen storage film with cold treatment and a palladium-based coating into a magnesium-based alloy layer, the problem of insufficient hydrogen storage capacity of existing films is solved, achieving high-efficiency hydrogen storage performance and reducing reaction temperature and pressure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI TIAN YANG STEEL TUBE
- Filing Date
- 2024-03-06
- Publication Date
- 2026-07-24
AI Technical Summary
The hydrogen storage capacity of existing composite films is far from reaching the theoretical hydrogen storage capacity of metallic Mg, and the reaction is carried out under high temperature and high pressure, resulting in high cost.
By introducing cold treatment and a palladium-based capping layer into the magnesium-based alloy layer, a composite hydrogen storage film of magnesium-based alloy layer and palladium-based capping layer was prepared by magnetron sputtering technology. Nitrogen doping was then used to improve the bonding strength and reaction efficiency.
It significantly improved the hydrogen storage capacity of the thin film, reduced the dehydrogenation temperature and reaction pressure, enhanced the hydrogen absorption and desorption rate, and approached the hydrogen storage performance of pure Mg.
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Figure CN118109791B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of hydrogen storage materials technology, and in particular to a composite hydrogen storage thin film and its preparation method. Background Technology
[0002] Hydrogen energy, as a green energy source, plays an important role in sustainable energy development due to its cleanliness, renewability, and ease of storage. Its energy density is as high as 142 MJ / kg, three times the calorific value of gasoline combustion, and its only byproduct is water, with no pollution. Currently, the key factor hindering the development of the "hydrogen economy" is hydrogen storage; therefore, the research and development of hydrogen storage materials has become crucial for the practical application and large-scale development of hydrogen energy utilization.
[0003] Hydrogen storage materials refer to materials that can reversibly absorb and release hydrogen under certain temperature and pressure. Current research reports mainly focus on solid hydrogen storage materials, such as AB5 type hydrogen storage alloys represented by LaNi5. Although they can reversibly absorb and release hydrogen at room temperature, their mass hydrogen storage density is low and their production cost is high. AB2 type hydrogen storage alloys represented by ZrV2 have a large theoretical hydrogen storage capacity, but their dehydrogenation is very difficult. AB type hydrogen storage alloys represented by TiFe can carry out hydrogen absorption and desorption reactions under relatively mild conditions, but the activation conditions are harsh, the activation cycle is long, and the theoretical hydrogen storage capacity is not high. A2B type hydrogen storage alloys represented by Mg2Ni have a hydrogen storage capacity as high as 7.6wt%, and the addition of the transition metal element Ni makes Mg2Ni exhibit excellent kinetic performance while maintaining a high hydrogen storage capacity, but it still requires a reaction temperature as high as 573K at a hydrogen pressure of 1 Bar.
[0004] Furthermore, existing technologies have proposed a Mg-TM (TM = Ti, Ni, Nb) ultra-multilayer composite hydrogen storage film, which significantly reduces its dehydrogenation temperature through a special Mg-TM structure. For example, CN108149211A provides a Mg-TM ultra-multilayer composite hydrogen storage film, which is a composite film with alternating Mg and TM atomic layers, and has a Pd capping layer on the outside of the composite film. This film achieves a hydrogen absorption capacity of 3.4 wt% in 500 s at 423 K and a hydrogen pressure of 1.15 MPa, and a dehydrogenation capacity of 2.1 wt% in 600 s at 423 K. However, the composite films provided in existing technologies are significantly different from the theoretical hydrogen storage capacity of metallic Mg, so there is an urgent need to provide a solution to improve this problem. Summary of the Invention
[0005] The purpose of this invention is to provide a composite hydrogen storage film and its preparation method. The cold treatment process can affect the metal crystal structure in the magnesium-based alloy layer, thereby increasing the overall hydrogen storage capacity of the film material and making it closer to the hydrogen storage capacity of pure Mg.
[0006] In a first aspect, the present invention provides a method for preparing a composite hydrogen storage film, comprising the following steps: pre-treating a substrate to obtain a sputtering substrate; sputtering a magnesium-based alloy layer on the surface of the substrate to be sputtered by magnetron sputtering to obtain an intermediate material; placing the intermediate material in an environment of -196 to -206°C for 2-3 hours to cool it, then removing it and allowing it to stand at room temperature; and sputtering a palladium-based capping layer on the surface of the magnesium-based alloy layer by magnetron sputtering to obtain a composite hydrogen storage film.
[0007] Optionally, during the pretreatment of the substrate to obtain the sputtering substrate, the substrate surface is alternately rinsed with deionized water and anhydrous ethanol, then ultrasonically cleaned in acetone, and finally vacuum dried to obtain the sputtering substrate.
[0008] Optionally, during the process of obtaining intermediate material by sputtering a magnesium-based alloy layer onto the surface of the substrate to be sputtered using magnetron sputtering, the substrate to be sputtered is fixed on a turntable in the magnetron sputtering chamber, at a speed of 2×10 -4 -5×10 -4 In a Pa environment, Mg-Ni alloy targets and Ti targets are used to perform magnetron sputtering on the substrate to be sputtered at sputtering powers of 120-150W and 30-50W respectively, with an argon flow rate of 100-120mL / min, to form a magnesium-based alloy layer and obtain an intermediate material.
[0009] Optionally, when the substrate to be sputtered is fixed on the turntable of the magnetron sputtering chamber, the temperature of the turntable surface is 50-55°C, and the rotation speed of the turntable is 12-15 rpm.
[0010] Optionally, when magnetron sputtering the substrate to be sputtered at an argon flow rate of 100-120 mL / min, nitrogen gas is simultaneously introduced into the magnetron sputtering chamber at a flow rate of 10-12 mL / min.
[0011] Optionally, when magnetron sputtering the substrate to be sputtered at an argon flow rate of 100-120 mL / min, the working gas pressure of the magnetron sputtering is 0.5-0.8 Pa.
[0012] Optionally, when using a Mg-Ni alloy target and a Ti target, and performing magnetron sputtering on the substrate to be sputtered at sputtering powers of 120-150W and 30-50W respectively, under an argon flow rate of 100-120mL / min, the Mg-Ni alloy target comprises 20-30mol% Ni and the balance Mg, and the purity of Ti in the Ti target is greater than or equal to 99.8%.
[0013] Optionally, when magnetron sputtering the substrate to be sputtered at an argon flow rate of 100-120 mL / min, the magnetron sputtering duration is controlled to be 10-12 min.
[0014] Optionally, during the process of fabricating a composite hydrogen storage film by sputtering a palladium-based capping layer onto the surface of the magnesium-based alloy layer using magnetron sputtering, the intermediate material is fixed on a turntable in the magnetron sputtering chamber, at a speed of 2×10⁻⁶. -4 -5×10 -4 In an environment of Pa, a Pd target is used to sputter the magnesium-based alloy layer on the surface of the intermediate material for 50-60 seconds at a sputtering power of 40-50W, an argon flow rate of 100-120mL / min, and a working pressure of 0.5-0.8Pa to form a palladium-based capping layer, thereby obtaining a composite hydrogen storage film.
[0015] Secondly, the present invention also provides a composite hydrogen storage film prepared by any of the above-mentioned optional preparation methods, wherein the composite hydrogen storage film is formed on the surface of a substrate, and the composite hydrogen storage film includes a magnesium-based alloy layer and a palladium-based capping layer formed by sputtering, and the palladium-based capping layer is located on the outside of the substrate. Attached Figure Description
[0016] Figure 1 A schematic flowchart of a method for preparing a composite hydrogen storage thin film provided by the present invention;
[0017] Figure 2 A schematic diagram of the structure of the composite hydrogen storage film prepared by the preparation method of the present invention. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects.
[0019] See Figure 1 This invention provides a method for preparing a composite hydrogen storage thin film, comprising the following steps:
[0020] S1. Pre-treatment: Pre-treatment of the substrate to obtain the substrate to be sputtered;
[0021] S2. Alloy sputtering: An intermediate material is prepared by sputtering a magnesium-based alloy layer onto the surface of the substrate to be sputtered using magnetron sputtering.
[0022] S3. Cryogenic treatment: The intermediate material is placed in an environment of -196 to -206°C for 2-3 hours and then removed and allowed to stand at room temperature.
[0023] S4. Encapsulation Sputtering: A composite hydrogen storage film is prepared by sputtering a palladium-based capping layer onto the surface of the magnesium-based alloy layer using magnetron sputtering.
[0024] In some embodiments, when performing step S1, the substrate used includes at least one of a glass slide and a silicon wafer, and the substrate used meets the purity and cleanliness required in the art for magnetron sputtering.
[0025] In some embodiments, during step S1, the substrate surface is alternately rinsed with deionized water and anhydrous ethanol, then ultrasonically cleaned in acetone, and finally vacuum dried to obtain the substrate to be sputtered. In practice, when rinsing the substrate surface alternately with deionized water and anhydrous ethanol, the number of rinsing cycles can be controlled to 3-5 times, thus balancing the cleaning effect while reducing resource waste.
[0026] In some embodiments, when performing step S1, after ultrasonic cleaning in acetone and vacuum drying, the wet substrate can be placed in a vacuum drying oven and dried at 0.2-0.5 standard atmospheres and 100-120°C until its quality does not change. After the substrate is cooled to room temperature in the oven, the pretreatment process of the substrate is completed.
[0027] In some embodiments, during step S2, the substrate to be sputtered is fixed on a turntable in the magnetron sputtering chamber, at a speed of 2×10⁻⁶. -4 -5×10 -4 In a Pa environment, Mg-Ni alloy targets and Ti targets are used to perform magnetron sputtering on the substrate to be sputtered at sputtering powers of 120-150W and 30-50W respectively, with an argon flow rate of 100-120mL / min, to form a magnesium-based alloy layer and obtain an intermediate material.
[0028] Specifically, when performing step S2 to fix the substrate to be sputtered on the turntable of the magnetron sputtering chamber, a domestically produced ultra-high vacuum magnetron sputtering device, model JGP560-B6, can be used. After fixing the substrate to be sputtered on the turntable, the temperature of the turntable surface is set to 50-55℃, and the rotation speed of the turntable is set to 12-15rpm. This is beneficial for forming a thin film of uniform thickness on the surface of the substrate to be sputtered during magnetron sputtering.
[0029] Specifically, in step S2, when magnetron sputtering of the substrate to be sputtered using a Mg-Ni alloy target and a Ti target at sputtering powers of 120-150W and 30-50W respectively, and an argon flow rate of 100-120mL / min, the Mg-Ni alloy target comprises 20-30 mol% Ni and the balance Mg, and the Ti target has a Ti purity greater than or equal to 99.8%. In practice, both the Mg-Ni alloy target and the Ti target used are cylindrical targets with standard diameters and thicknesses; for example, the target diameter can be 60mm and the target thickness can be 4.5mm.
[0030] Specifically, during step S2, when magnetron sputtering is performed on the substrate at an argon flow rate of 100-120 mL / min, nitrogen gas is simultaneously introduced into the magnetron sputtering chamber at a flow rate of 10-12 mL / min. This allows nitrogen to be doped into the thin film during magnetron sputtering, forming a Mg-Ni-Ti-N alloy film. The addition of nitrogen not only effectively alleviates residual stress between the magnesium alloy layer and the substrate, improving their bonding strength, but also promotes the hydrogen absorption and desorption processes of the magnesium alloy layer. Under the same temperature and hydrogen pressure, this significantly increases the hydrogen storage capacity of the film and exhibits a faster hydrogen desorption / absorption rate at the same temperature.
[0031] Specifically, when performing step S2, magnetron sputtering is carried out on the substrate to be sputtered at an argon flow rate of 100-120 mL / min, the working gas pressure of magnetron sputtering is 0.5-0.8 Pa, and the magnetron sputtering time is controlled to be 10-12 min.
[0032] In some embodiments, during step S3, the intermediate material is immersed in liquid nitrogen, cooled for 2-3 hours, and then removed and placed in an air environment to warm up to room temperature. Deep cryogenic treatment of the intermediate material can greatly promote the bonding between the magnesium-based alloy layer and the substrate. Furthermore, because the cryogenic treatment can affect the metal crystal structure in the magnesium-based alloy layer, it can also increase the overall hydrogen storage capacity of the thin film material, making it closer to the hydrogen storage capacity of pure Mg.
[0033] In some embodiments, during step S4, the intermediate material is fixed on a turntable within the magnetron sputtering chamber at a 2×10⁻⁶ rpm. -4 -5×10 -4In an environment of Pa, a Pd target is used at a sputtering power of 40-50W, an argon flow rate of 100-120mL / min, and a working pressure of 0.5-0.8Pa to sputter the magnesium-based alloy layer on the surface of the intermediate material for 50-60 seconds, forming a palladium-based capping layer to obtain a composite hydrogen storage film. In practice, during magnetron sputtering in steps S2 and S4, the distance between the target and the substrate is 60mm.
[0034] See Figure 2 The present invention also provides a composite hydrogen storage film prepared by the preparation method in any of the above embodiments. The composite hydrogen storage film 2 is formed on the surface of the substrate 1. The composite hydrogen storage film 2 includes a magnesium-based alloy layer 21 and a palladium-based capping layer 22 formed by sputtering, and the palladium-based capping layer 22 is located on the outside opposite to the substrate 1.
[0035] Example 1
[0036] This embodiment 1 provides a method for preparing a composite hydrogen storage thin film, including the following steps:
[0037] S1. Pretreatment: After rinsing the surface of the monocrystalline silicon wafer three times with deionized water and anhydrous ethanol, the monocrystalline silicon wafer is immersed in acetone and ultrasonically cleaned at an ultrasonic frequency of 200W for 15 minutes. The monocrystalline silicon wafer is then removed and transferred to a vacuum drying oven and dried at 0.2 standard atmospheres and 120°C until the quality of the monocrystalline silicon wafer does not change. After cooling to room temperature in the furnace, the pretreated monocrystalline silicon wafer is obtained, which is the substrate to be sputtered.
[0038] S2. Alloy Sputtering: The substrate to be sputtered is fixed on a turntable in the magnetron sputtering chamber of the JGP560-B6 ultra-high vacuum magnetron sputtering equipment, and Mg is installed. 75 Ni 25 The alloy target and Ti target are positioned 60 mm away from the substrate to be sputtered. The vacuum level in the magnetron sputtering chamber is adjusted to 2 × 10⁻⁶ using a vacuum pump. -4 -5×10 -4 Pa, and argon gas with a purity greater than 99.99% was introduced into the magnetron sputtering chamber to adjust the vacuum level in the chamber to a working pressure of 0.6 Pa; at an argon flow rate of 110 mL / min, sputtering was performed on Mg at a sputtering power of 120 W. 75 Ni 25 The alloy target was sputtered with a sputtering power of 30W on the Ti target. The turntable temperature was controlled at 55℃ and the rotation speed at 13rpm. The total sputtering time was controlled at 10min. A magnesium-based alloy layer was formed on the surface of the substrate to be sputtered, and the intermediate material was obtained.
[0039] S3. Cryogenic treatment: Immerse the intermediate material in liquid nitrogen at -196℃ for 2 hours, then remove it and place it in an air environment to warm up to room temperature. Use nitrogen to blow away the condensate on the surface of the intermediate material.
[0040] S4. Encapsulation Sputtering: After completing step S3, fix the intermediate material on the turntable in the magnetron sputtering chamber of the JGP560-B6 ultra-high vacuum magnetron sputtering equipment. Install the Pd target to a position 60mm away from the intermediate material. Use a vacuum pump to adjust the vacuum level in the magnetron sputtering chamber to 2×10⁻⁶. -4 -5×10 -4 Pa, and argon gas with a purity greater than 99.99% was introduced into the magnetron sputtering chamber to adjust the vacuum level in the chamber to a working pressure of 0.6 Pa; under an argon flow rate of 110 mL / min, sputtering was performed on the Pd target with a sputtering power of 40 W, the turntable temperature was controlled at 55℃ and the rotation speed at 13 rpm, and the total sputtering time was controlled at 55 s. After that, a palladium-based coating layer was formed on the surface of the intermediate material, and a composite hydrogen storage film was obtained.
[0041] Example 2
[0042] This embodiment 2 provides a method for preparing a composite hydrogen storage thin film, including the following steps:
[0043] S1. Pretreatment: After rinsing the surface of the monocrystalline silicon wafer three times with deionized water and anhydrous ethanol, the monocrystalline silicon wafer is immersed in acetone and ultrasonically cleaned at an ultrasonic frequency of 200W for 15 minutes. The monocrystalline silicon wafer is then removed and transferred to a vacuum drying oven and dried at 0.2 standard atmospheres and 120°C until the quality of the monocrystalline silicon wafer does not change. After cooling to room temperature in the furnace, the pretreated monocrystalline silicon wafer is obtained, which is the substrate to be sputtered.
[0044] S2. Alloy Sputtering: The substrate to be sputtered is fixed on a turntable in the magnetron sputtering chamber of the JGP560-B6 ultra-high vacuum magnetron sputtering equipment, and Mg is installed. 75 Ni 25 The alloy target and Ti target are positioned 60 mm away from the substrate to be sputtered. The vacuum level in the magnetron sputtering chamber is adjusted to 2 × 10⁻⁶ using a vacuum pump. -4 -5×10 -4 Pa, and argon gas with a purity greater than 99.99% was introduced into the magnetron sputtering chamber to adjust the vacuum level in the chamber to a working pressure of 0.6 Pa; under an argon flow rate of 110 mL / min and a nitrogen flow rate of 11 mL / min, sputtering was performed on Mg at a sputtering power of 120 W. 75 Ni 25The alloy target was sputtered with a sputtering power of 30W on the Ti target. The turntable temperature was controlled at 55℃ and the rotation speed at 13rpm. The total sputtering time was controlled at 10min. A magnesium-based alloy layer was formed on the surface of the substrate to be sputtered, and the intermediate material was obtained.
[0045] S3. Cryogenic treatment: Immerse the intermediate material in liquid nitrogen at -196℃ for 2 hours, then remove it and place it in an air environment to warm up to room temperature. Use nitrogen to blow away the condensate on the surface of the intermediate material.
[0046] S4. Encapsulation Sputtering: After completing step S3, fix the intermediate material on the turntable in the magnetron sputtering chamber of the JGP560-B6 ultra-high vacuum magnetron sputtering equipment. Install the Pd target to a position 60mm away from the intermediate material. Use a vacuum pump to adjust the vacuum level in the magnetron sputtering chamber to 2×10⁻⁶. -4 -5×10 -4 Pa, and argon gas with a purity greater than 99.99% was introduced into the magnetron sputtering chamber to adjust the vacuum level in the chamber to a working pressure of 0.6 Pa; under an argon flow rate of 110 mL / min, sputtering was performed on the Pd target with a sputtering power of 40 W, the turntable temperature was controlled at 55℃ and the rotation speed at 13 rpm, and the total sputtering time was controlled at 55 s. After that, a palladium-based coating layer was formed on the surface of the intermediate material, and a composite hydrogen storage film was obtained.
[0047] Comparative Example 1
[0048] Comparative Example 1 provides a method for preparing a composite hydrogen storage thin film, comprising the following steps:
[0049] S1. Pretreatment: After rinsing the surface of the monocrystalline silicon wafer three times with deionized water and anhydrous ethanol, the monocrystalline silicon wafer is immersed in acetone and ultrasonically cleaned at an ultrasonic frequency of 200W for 15 minutes. The monocrystalline silicon wafer is then removed and transferred to a vacuum drying oven and dried at 0.2 standard atmospheres and 120°C until the quality of the monocrystalline silicon wafer does not change. After cooling to room temperature in the furnace, the pretreated monocrystalline silicon wafer is obtained, which is the substrate to be sputtered.
[0050] S2. Alloy Sputtering: The substrate to be sputtered is fixed on a turntable in the magnetron sputtering chamber of the JGP560-B6 ultra-high vacuum magnetron sputtering equipment, and Mg is installed. 75 Ni 25 The alloy target and Ti target are positioned 60 mm away from the substrate to be sputtered. The vacuum level in the magnetron sputtering chamber is adjusted to 2 × 10⁻⁶ using a vacuum pump. -4 -5×10 -4 Pa, and argon gas with a purity greater than 99.99% was introduced into the magnetron sputtering chamber to adjust the vacuum level in the chamber to a working pressure of 0.6 Pa; at an argon flow rate of 110 mL / min, sputtering was performed on Mg at a sputtering power of 120 W.75 Ni 25 The alloy target was sputtered with a sputtering power of 30W on the Ti target. The turntable temperature was controlled at 55℃ and the rotation speed at 13rpm. The total sputtering time was controlled at 10min. A magnesium-based alloy layer was formed on the surface of the substrate to be sputtered, and the intermediate material was obtained.
[0051] S3. Encapsulation Sputtering: Fix the intermediate material on the turntable in the magnetron sputtering chamber of the JGP560-B6 ultra-high vacuum magnetron sputtering equipment, install the Pd target to a position 60mm away from the intermediate material, and use a vacuum pump to adjust the vacuum level in the magnetron sputtering chamber to 2×10⁻⁶. -4 -5×10 -4 Pa, and argon gas with a purity greater than 99.99% was introduced into the magnetron sputtering chamber to adjust the vacuum level in the chamber to a working pressure of 0.6 Pa; under an argon flow rate of 110 mL / min, sputtering was performed on the Pd target with a sputtering power of 40 W, the turntable temperature was controlled at 55℃ and the rotation speed at 13 rpm, and the total sputtering time was controlled at 55 s. After that, a palladium-based coating layer was formed on the surface of the intermediate material, and a composite hydrogen storage film was obtained.
[0052] Performance testing
[0053] The hydrogen absorption kinetics of the composite hydrogen storage membranes prepared in Examples 1, 2, and 1 were tested using a Sieverts-type gas reaction controller. After placing the composite hydrogen storage membranes prepared in Examples 1, 2, and 1 in an environment of 150°C and 2 MPa hydrogen pressure for 10 min, the hydrogen absorption capacity of the three composite hydrogen storage membranes was measured, and the saturation hydrogen absorption capacity and the time required when the composite hydrogen storage membrane reaches its own saturation hydrogen absorption capacity were calculated. The results are shown in Table 1 below.
[0054] The hydrogen desorption kinetics of the composite hydrogen storage films prepared in Examples 1, 2, and Comparative Example 1 were tested using a HyEnergy PCTPro 2000 gas desorption instrument. The composite hydrogen storage films after saturation adsorption were placed in an argon atmosphere, and a desorption test was performed starting at 20°C. The initial hydrogen desorption temperature and peak hydrogen desorption temperature of each of the three composite hydrogen storage films were measured, and the results are shown in Table 2 below. The hydrogen desorption performance of the composite hydrogen storage films after saturation adsorption was tested at 150°C, and the hydrogen desorption amount of each of the three composite hydrogen storage films was recorded after 5 hours of desorption, and the results are shown in Table 2 below.
[0055] Table 1 Comparison of hydrogen absorption performance
[0056] Example 1 3.4 3.6 698 Example 2 3.8 4.0 672 Comparative Example 1 2.4 3.3 845
[0057] Table 2
[0058] Example 1 40 210 1.9 Example 2 38 202 2.2 Comparative Example 1 44 220 1.1
[0059] As can be seen from Tables 1 and 2, the composite hydrogen storage film prepared by the method provided by the present invention has a higher saturated hydrogen absorption capacity, and can start to release hydrogen at a lower temperature. Moreover, its hydrogen release performance at 150°C is significantly better than that of the film in Comparative Example 1.
[0060] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.
Claims
1. A method for preparing a composite hydrogen storage thin film, characterized in that, Includes the following steps: A substrate is pretreated to obtain a sputtering substrate. A magnesium-based alloy layer is formed on the surface of the substrate using a Mg-Ni alloy target and a Ti target to obtain an intermediate material. The intermediate material is placed in an environment of -196 to -206°C for 2-3 hours to cool, then removed and allowed to stand at room temperature. A palladium-based capping layer is then formed on the surface of the magnesium-based alloy layer by magnetron sputtering to obtain a composite hydrogen storage film.
2. The preparation method according to claim 1, characterized in that, In the process of pre-treating the substrate to obtain the sputtering substrate, the surface of the substrate is rinsed alternately with deionized water and anhydrous ethanol, then ultrasonically cleaned in acetone, and then vacuum dried to obtain the sputtering substrate.
3. The preparation method according to claim 1, characterized in that, In the process of obtaining intermediate materials by sputtering a magnesium-based alloy layer onto the surface of a substrate using magnetron sputtering, the substrate is fixed on a turntable in the magnetron sputtering chamber. (2×10) -4 -5×10 -4 In a Pa environment, Mg-Ni alloy targets and Ti targets are used to perform magnetron sputtering on the substrate to be sputtered at sputtering powers of 120-150W and 30-50W respectively, with an argon flow rate of 100-120mL / min, to form a magnesium-based alloy layer and obtain an intermediate material.
4. The preparation method according to claim 3, characterized in that, When the substrate to be sputtered is fixed on the turntable in the magnetron sputtering chamber, the temperature of the turntable surface is 50-55°C, and the rotation speed of the turntable is 12-15 rpm.
5. The preparation method according to claim 3, characterized in that, When magnetron sputtering the substrate to be sputtered at an argon flow rate of 100-120 mL / min, nitrogen gas is simultaneously introduced into the magnetron sputtering chamber at a flow rate of 10-12 mL / min.
6. The preparation method according to claim 3, characterized in that, When magnetron sputtering the substrate to be sputtered at an argon flow rate of 100-120 mL / min, the working gas pressure for magnetron sputtering is 0.5-0.8 Pa.
7. The preparation method according to claim 3, characterized in that, When the substrate to be sputtered is magnetron sputtered using a Mg-Ni alloy target and a Ti target at sputtering powers of 120-150W and 30-50W respectively, and an argon flow rate of 100-120mL / min, the Mg-Ni alloy target comprises 20-30mol% Ni and the balance Mg, and the purity of Ti in the Ti target is greater than or equal to 99.8%.
8. The preparation method according to claim 3, characterized in that, When magnetron sputtering the substrate to be sputtered at an argon flow rate of 100-120 mL / min, the magnetron sputtering time is controlled to be 10-12 min.
9. The preparation method according to claim 1, characterized in that, In the process of fabricating a composite hydrogen storage film by sputtering a palladium-based capping layer onto the surface of the magnesium-based alloy layer using magnetron sputtering, the intermediate material is fixed on a turntable in the magnetron sputtering chamber at a speed of 2×10⁻⁶. -4 -5×10 -4 In an environment of Pa, a Pd target is used to sputter the magnesium-based alloy layer on the surface of the intermediate material for 50-60 seconds at a sputtering power of 40-50W, an argon flow rate of 100-120mL / min, and a working pressure of 0.5-0.8Pa to form a palladium-based capping layer, thereby obtaining a composite hydrogen storage film.
10. A composite hydrogen storage thin film prepared by the preparation method according to any one of claims 1 to 9, characterized in that, The composite hydrogen storage film is formed on the surface of a substrate. The composite hydrogen storage film includes a magnesium-based alloy layer and a palladium-based capping layer formed by sputtering, and the palladium-based capping layer is located on the outside of the substrate.