Composite hydrogen storage membrane material and preparation method therefor, and hydrogen storage tank

Abstract

A composite hydrogen storage membrane material, comprising a substrate (100) and a hydrogen storage layer (110) arranged on the substrate (100), wherein the substrate (100) is a flexible substrate, and the substrate (100) and the hydrogen storage layer (110) are of a multi-layer curled structure as a whole; the hydrogen storage layer (110) covers the substrate (100); and the hydrogen storage layer (110) comprises a plurality of vanadium metal layers (111) and a plurality of niobium metal layers (112), the vanadium metal layers (111) and the niobium metal layers (112) are sequentially and alternately stacked on the substrate (100), and adjacent vanadium metal layers (111) and niobium metal layers (112) are in contact with each other.

Description

Composite hydrogen storage membrane material, preparation method thereof and hydrogen storage tank

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on June 27, 2023, with application number 2023107643576 and public name “Composite hydrogen storage membrane material, preparation method thereof and hydrogen storage tank”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of hydrogen storage, and in particular to a composite hydrogen storage membrane material, a preparation method thereof, and a hydrogen storage tank. Background Art

[0003] Hydrogen is an important secondary energy source. Hydrogen can be obtained through water electrolysis, and its combustion product is also water. Furthermore, hydrogen has the advantage of a high calorific value, making it considered an ideal clean energy source for sustainable development. Furthermore, hydrogen's ease of transport and wide applicability make it a promising supplementary energy source for the electric power system.

[0004] How to store hydrogen efficiently and safely is an important factor restricting the further development of hydrogen energy. Current hydrogen storage methods include gaseous hydrogen storage, liquid hydrogen storage and solid hydrogen storage. Gaseous hydrogen storage refers to compressing hydrogen and storing it in a high-pressure resistant container, but this has high requirements for the performance of the container itself. Liquid hydrogen storage refers to storing hydrogen after pressurization and liquefaction, which also has high requirements for the container and also poses a greater safety hazard. Solid-state hydrogen storage refers to filling a hydrogen storage tank with a metal powder material that can react with hydrogen, and then injecting hydrogen into the hydrogen storage tank and combining the hydrogen with the metal powder material by, for example, pressurizing or cooling. When needed, the hydrogen storage material is heated to release the hydrogen so that it separates from the metal powder material.

[0005] Compared with other metals that can absorb hydrogen, metallic vanadium has a higher hydrogen reserve, but hydrogen storage through metallic vanadium has the problem of poor reversibility.

[0006] Summary of the Invention

[0007] According to some embodiments of the present disclosure, a composite hydrogen storage film material is provided, comprising: a substrate and a hydrogen storage layer arranged on the substrate, wherein the substrate is a flexible substrate, and the substrate and the hydrogen storage layer as a whole have a multi-layer curled structure, the hydrogen storage layer is covered on the substrate, and the hydrogen storage layer comprises a plurality of vanadium metal layers and a plurality of niobium metal layers, the vanadium metal layers and the niobium metal layers are alternately stacked in sequence on the substrate, and adjacent vanadium metal layers are in contact with each other.

[0008] In some embodiments of the present disclosure, the thickness of the vanadium metal layer is 5 nm to 100 nm.

[0009] In some embodiments of the present disclosure, the thickness of the niobium metal layer is 1 nm to 10 nm.

[0010] In some embodiments of the present disclosure, the hydrogen storage layer has micropores, and the porosity of the hydrogen storage layer is 10% to 50%.

[0011] In some embodiments of the present disclosure, in the hydrogen storage layer, the layer farthest from the substrate is the niobium metal layer.

[0012] In some embodiments of the present disclosure, the total thickness of the hydrogen storage layer is 100 nm to 5000 nm.

[0013] In some embodiments of the present disclosure, in the hydrogen storage layer, the total number of the vanadium metal layers is 20 to 500.

[0014] In some embodiments of the present disclosure, in the hydrogen storage layer, the total number of niobium metal layers is 20 to 500.

[0015] In some embodiments of the present disclosure, the hydrogen storage layer is provided on both opposite sides of the substrate.

[0016] Furthermore, the present disclosure also provides a method for preparing a composite hydrogen storage film material, the composite hydrogen storage film material comprising: a substrate and a hydrogen storage layer disposed on the substrate, the substrate being a flexible substrate, the substrate and the hydrogen storage layer having a multi-layer curled structure as a whole, the hydrogen storage layer covering the substrate, the hydrogen storage layer comprising multiple vanadium metal layers and multiple niobium metal layers, the vanadium metal layers and the niobium metal layers being alternately stacked on the substrate, with adjacent vanadium metal layers in contact with each other;

[0017] The preparation method comprises the following steps:

[0018] providing the substrate;

[0019] Vanadium metal is sputtered multiple times and niobium metal is sputtered multiple times on the substrate to form multiple layers of niobium metal layers and multiple layers of vanadium metal layers respectively. During the sputtering process, the vanadium metal and the niobium metal are sputtered alternately.

[0020] In some embodiments of the present disclosure, when niobium metal is sputtered on the prepared vanadium metal layer, the sputtering power is controlled so that niobium atoms are embedded in the vanadium metal layer.

[0021] In some embodiments of the present disclosure, in the step of sputtering vanadium metal, the sputtering power density is controlled to be 10W / cm 2~20W / cm 2 .

[0022] In some embodiments of the present disclosure, in the step of sputtering niobium metal, the sputtering power density is controlled to be 15W / cm 2 ~30W / cm 2 .

[0023] In some embodiments of the present disclosure, in the step of sputtering vanadium metal on the substrate, the thickness of each vanadium metal layer is controlled to be 5 nm to 100 nm.

[0024] In some embodiments of the present disclosure, in the step of sputtering niobium metal on the substrate, the thickness of each niobium metal layer is controlled to be 1 nm to 10 nm.

[0025] In some embodiments of the present disclosure, in the hydrogen storage layer, the total number of the vanadium metal layers is 20 to 500.

[0026] In some embodiments of the present disclosure, in the hydrogen storage layer, the total number of niobium metal layers is 20 to 500.

[0027] In some embodiments of the present disclosure, the hydrogen storage layer has micropores, and the porosity of the hydrogen storage layer is 10% to 50%.

[0028] In some embodiments of the present disclosure, during the process of sputtering vanadium metal multiple times and sputtering niobium metal multiple times, the following steps are further included:

[0029] introducing a gasifying agent into the deposition chamber so that the gasifying agent adheres to the previously prepared vanadium metal layer or niobium metal layer;

[0030] Continue to alternately sputter vanadium metal and niobium metal on the vanadium metal layer or the niobium metal layer to which the gasification agent is attached, and then perform a temperature-raising treatment on the substrate to volatilize the gasification agent.

[0031] In some embodiments of the present disclosure, the step of introducing a gasifying agent into the deposition chamber is performed after sputtering the vanadium metal, so that the gasifying agent adheres to the previously prepared vanadium metal layer.

[0032] In some embodiments of the present disclosure, the gasifying agent is water.

[0033] Furthermore, the present disclosure also provides a hydrogen storage tank, which includes a tank body and the composite hydrogen storage film material as described in the above embodiment, wherein the composite hydrogen storage film material is arranged in the tank body. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG1 is a schematic structural diagram of a composite hydrogen storage membrane material;

[0035] FIG2 is a cross-sectional schematic diagram of a multi-layer curled structure formed based on the composite hydrogen storage membrane material in FIG1 ;

[0036] FIG3 is a schematic diagram of the steps of a method for preparing a composite hydrogen storage membrane material;

[0037] The reference numerals and their meanings are as follows: 100, substrate; 110, hydrogen storage layer; 111, vanadium metal layer; 112, niobium metal layer. DETAILED DESCRIPTION

[0038] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items, and "more than" as used herein includes two or more items.

[0040] In the present invention, unless otherwise indicated, the sum of the parts of each component in the composition can be 100 parts by weight. Unless otherwise indicated, the basis for percentages (including weight percentages) in the present invention is the total weight of the composition. In addition, "wt%" herein means mass percentage, and "at%" means atomic percentage.

[0041] In this article, unless otherwise indicated, each reaction step may be carried out in the order in which it is presented, or may be carried out out of the order in which it is presented. For example, other steps may be included between each reaction step, and the order of the reaction steps may be appropriately reversed. This is something that can be determined by a skilled person based on conventional knowledge and experience. Preferably, the reaction methods described herein are carried out sequentially.

[0042] After absorbing hydrogen, metallic vanadium can successively form three hydrides, namely vanadium hydride (V2H), vanadium hydride (VH) and vanadium dihydride (VH2). When it starts to absorb hydrogen, hydrogen molecules are adsorbed on the surface of the vanadium metal, and the hydrogen molecules break bonds to form hydrogen atoms. The hydrogen atoms diffuse into the crystal lattice of the metallic vanadium and form interstitial solid solutions. When metallic vanadium absorbs hydrogen, it first forms hydrogen-poor vanadium hydride, then forms vanadium hydride, and finally forms hydrogen-rich vanadium dihydride. When releasing hydrogen, vanadium dihydride loses hydrogen atoms and forms vanadium hydride or vanadium hydride. Since vanadium hydride is relatively stable, vanadium metal can only release about half of the hydrogen under normal circumstances, which limits its actual hydrogen storage capacity. In addition, there is also a mismatch problem between the lattices of vanadium metal and its hydrides, which can lead to the pulverization of vanadium metal and ultimately the loss of hydrogen storage capacity.

[0043] In order to improve the reversibility of vanadium hydrogen storage, the present disclosure provides a composite hydrogen storage film material, which includes: a substrate and a hydrogen storage layer arranged on the substrate, the substrate is a flexible substrate, the substrate and the hydrogen storage layer have a multi-layer curled structure as a whole, the hydrogen storage layer is conformally covered on the substrate, the hydrogen storage layer includes multiple vanadium metal layers and multiple niobium metal layers, the vanadium metal layers and the niobium metal layers are alternately stacked on the substrate in sequence, and adjacent vanadium metal layers and niobium metal layers are in contact with each other.

[0044] Compared to a single vanadium metal, by providing a niobium metal layer alternating with the vanadium metal layer, an alloy-like structure can be formed at the interface between the niobium metal layer and the vanadium metal layer, and lattice defects can occur in the vanadium metal layer. Furthermore, the vanadium metal layer and the niobium metal layer that are alternately stacked are provided on a substrate and form a multi-layer curled structure as a whole, which can not only effectively increase the overall effective hydrogen absorption area of ​​the hydrogen storage layer, but also cause the vanadium metal layer close to the substrate to undergo structural deformation through the curled structure, thereby increasing the overall lattice defects. On the one hand, this can reduce the stability of vanadium hydride, making hydrogen easier to absorb and release. On the other hand, the niobium metal layer can also be used to support the vanadium metal layer to maintain the overall structural stability of the vanadium metal layer, prevent the vanadium metal layer from de-powdering due to volume changes, and thus improve the reversibility of hydrogen storage in the vanadium metal layer.

[0045] Figure 1 of the present disclosure provides a schematic structural diagram of a composite hydrogen storage membrane. As shown in Figure 1 , the composite hydrogen storage membrane comprises a substrate 100 and a hydrogen storage layer 110 disposed on substrate 100. Hydrogen storage layer 110 conformally covers substrate 100 and comprises multiple vanadium metal layers 111 and multiple niobium metal layers 112. The vanadium metal layers 111 and niobium metal layers 112 are alternately stacked on substrate 100, with adjacent vanadium metal layers 111 and niobium metal layers 112 in contact with each other. Ellipses indicate the alternating stacking of multiple vanadium metal layers 111 and multiple niobium metal layers 112.

[0046] It can be understood that the contact between adjacent vanadium metal layers 111 and niobium metal layers 112 is equivalent to introducing niobium metal between the multiple vanadium metal layers 111. This can cause defects in the lattice of the vanadium metal layers 111, thereby reducing the stability of the vanadium hydride or divanadium hydride, allowing the hydrogen therein to be released more easily. In addition, the niobium metal layers 112 and vanadium metal layers 111 can be deposited, such as by physical vapor deposition, making them easier to prepare compared to traditional casting methods.

[0047] In some examples of this embodiment, each vanadium metal layer 111 can be a continuous film layer. A continuous film layer means that the vanadium metal layer 111 entirely covers the substrate 100 or entirely covers another metal layer located below. Furthermore, each niobium metal layer 112 can be a continuous or discontinuous film layer. When the niobium metal layer 112 is a discontinuous film layer, the niobium metal layer 112 can include a plurality of spaced-apart niobium metal islands.

[0048] It is understood that the vanadium metal layer 111 herein refers to the vanadium metal contained in the vanadium metal layer 111, and the vanadium metal layer 111 may also contain other metal atoms. The niobium metal layer 112 herein refers to the niobium metal contained in the niobium metal layer 112, and the niobium metal layer 112 may also contain other metal atoms. In some examples of this embodiment, the vanadium metal layer 111 may contain niobium metal atoms. By further doping the vanadium metal layer 111 with niobium metal atoms, the lattice defects in the vanadium metal layer 111 can be further increased, thereby further reducing the stability of the vanadium hydride or divanadium hydride.

[0049] In some examples of this embodiment, the thickness of each vanadium metal layer 111 can be 5 nm to 100 nm. By setting the thickness of each vanadium metal layer 111 to be less than 100 nm, the interior of the vanadium metal layer 111 can be closer to the adjacent niobium metal layer 112, and the vanadium metal layer 111 can have relatively more defects. By setting the thickness of each vanadium metal layer 111 to be greater than 5 nm, the vanadium metal layer 111 can be formed into a continuous film layer, thereby ensuring that the vanadium metal layer 111 has a higher hydrogen storage capacity.

[0050] Furthermore, the thickness of each vanadium metal layer 111 may be 5 nm, 10 nm, 20 nm, 30 nm, 50 nm, 80 nm, or 100 nm. Furthermore, the thickness of each vanadium metal layer 111 may also be within a range between any two of the above thicknesses.

[0051] In some examples of this embodiment, the thickness of each niobium metal layer 112 can be 1 nm to 10 nm. The main function of the niobium metal layer 112 is to embed into the vanadium metal layer 111 to introduce lattice defects. Setting the thickness of the niobium metal layer 112 to 1 nm can minimize the amount of niobium metal layer 112 introduced, facilitate the diffusion of hydrogen atoms between adjacent vanadium metal layers 111, and improve the overall hydrogen storage capacity of the composite hydrogen storage film material.

[0052] Furthermore, the thickness of each niobium metal layer 112 may be 1 nm, 2 nm, 3 nm, 5 nm, 7 nm, or 10 nm. Furthermore, the thickness of each niobium metal layer 112 may also be within a range between any two of the above thicknesses.

[0053] In some examples of this embodiment, the total thickness of the hydrogen storage layer 110 in the composite hydrogen storage film can be 100 nm to 5000 nm. By controlling the total thickness of the hydrogen storage layer 110 to 100 nm to 5000 nm, the composite hydrogen storage film can be guaranteed to have a high hydrogen storage capacity while facilitating the diffusion of hydrogen atoms in the hydrogen storage layer 110, thereby ensuring the absorption and release rate of hydrogen.

[0054] Furthermore, the total thickness of the hydrogen storage layer 110 may be 100 nm, 500 nm, 1000 nm, 2000 nm, 3000 nm or 5000 nm. Furthermore, the total thickness of the hydrogen storage layer 110 may also be within a range between any two of the above thicknesses.

[0055] As shown in FIG1 , in some examples of this embodiment, in the hydrogen storage layer 110, the total number of vanadium metal layers 111 can be 20 to 500 layers. For example, the total number of vanadium metal layers 111 can be 20, 50, 100, 200, 300, or 500 layers. Furthermore, the total number of vanadium metal layers 111 can also be within a range between any two of the aforementioned numbers. Controlling the total number of vanadium metal layers 111 can ensure that the vanadium metal layer 111 has a high hydrogen atom diffusion rate while saving specific process technology.

[0056] As shown in FIG1 , in some examples of this embodiment, in the hydrogen storage layer 110, the total number of niobium metal layers 112 may be 20 to 500 layers. For example, the total number of niobium metal layers 112 may be 20, 50, 100, 200, 300, or 500 layers. The total number of niobium metal layers 112 may also be within a range between any two of the aforementioned numbers.

[0057] In some examples of this embodiment, the hydrogen storage layer 110 may have micropores. The micropores in the hydrogen storage layer 110 can increase the specific surface area of ​​the hydrogen storage layer 110, thereby providing the hydrogen storage layer 110 with more hydrogen adsorption sites. Furthermore, at least some of the micropores can be provided in the vanadium metal layer 111, which can further increase the lattice defects of the vanadium metal layer 111, further reducing the binding stability between hydrogen atoms and the vanadium metal, and increasing the diffusion rate of hydrogen atoms in the vanadium metal layer 111.

[0058] In some examples of this embodiment, the porosity of the hydrogen storage layer 110 may be 10% to 50%, so as to maintain the structural integrity of the hydrogen storage layer 110 while ensuring that the hydrogen storage layer 110 has a high hydrogen storage capacity and a high hydrogen absorption and release rate.

[0059] In some examples of this embodiment, in the hydrogen storage layer 110 , the porosity of the hydrogen storage layer 110 may be 10%, 20%, 30%, 40% or 50%, or the porosity of the hydrogen storage layer 110 may be within a range between any two of the above porosities.

[0060] As shown in FIG1 , in some examples of this embodiment, in hydrogen storage layer 110, the layer farthest from substrate 100 is niobium metal layer 112. Niobium metal layer 112 is configured as the layer farthest from substrate 100. Niobium metal layer 112 protects vanadium metal layer 111 located within the hydrogen storage layer 110 from the outermost layer, ensuring structural stability of vanadium metal layer 111 during hydrogen absorption and release.

[0061] 1 , in some examples of this embodiment, hydrogen storage layers 110 are provided on two opposite surfaces of the substrate 100 , which can further increase the hydrogen storage capacity of the composite hydrogen storage film material.

[0062] It is understood that the composite hydrogen storage membrane material shown in FIG1 has a long straight planar structure, but the composite hydrogen storage membrane material is not limited to a long straight planar structure. For example, the composite hydrogen storage membrane material can also be curved, bent, or coiled.

[0063] FIG2 shows a cross-sectional schematic diagram of a multi-layered rolled structure formed based on the composite hydrogen storage film material in FIG1 . Referring to FIG2 , in the composite hydrogen storage film material, the substrate 100 is a flexible substrate, and the substrate 100 and the hydrogen storage layer 110 as a whole have a multi-layered rolled structure. The multi-layered rolled structure refers to the substrate 100 and the hydrogen storage layer 110 being rotated as a whole around a rotation axis to form a continuous, multi-layered cylindrical structure distributed from the inside out. It is understood that the hydrogen storage layer 110 can be attached to the substrate 100 as a whole, so that the hydrogen storage layer 110 and the substrate 100 can maintain the stability of the overall structure when rolled.

[0064] In some examples of this embodiment, the flexible substrate may be selected from a polymer film or a metal foil. The polymer film may include, but is not limited to, one or more of polyimide, polyethylene, polypropylene, and polymethyl methacrylate. The metal foil may include, but is not limited to, one or more of copper, aluminum, iron, nickel, and titanium.

[0065] Furthermore, the present disclosure also provides a method for preparing a composite hydrogen storage membrane material as in the above embodiment. FIG3 is a schematic diagram of the steps of a method for preparing a composite hydrogen storage membrane material. Referring to FIG3 , the preparation method includes steps S1 to S4, which are specifically as follows.

[0066] Step S1: providing a substrate 100.

[0067] In some examples of this embodiment, substrate 100 may be a flexible substrate. The flexible substrate may be selected from a polymer film or a metal foil. The polymer film may include, but is not limited to, one or more of polyimide, polyethylene, polypropylene, and polymethyl methacrylate. The metal foil may include, but is not limited to, one or more of copper, aluminum, iron, nickel, and titanium.

[0068] In some examples of this embodiment, the thickness of the selected substrate 100 is 1 μm to 100 μm. For example, in this embodiment, a copper foil with a thickness of 5 μm can be selected as the substrate 100 .

[0069] In some examples of this embodiment, the step of roughening the substrate 100 may be further included. The purpose of roughening the substrate 100 is to form an undulating structure on the surface of the substrate 100, which can increase the surface area of ​​the substrate 100 and the overall surface area of ​​the subsequently prepared hydrogen storage layer 110.

[0070] In some examples of this embodiment, the roughening treatment method for the substrate 100 can be selected from one or more of plasma bombardment, laser irradiation, sandblasting, frosting, and embossing. Plasma bombardment refers to bombarding the surface of the substrate 100 with plasma. Plasma treatment can be performed in a coating device. Plasma treatment can not only clean impurities from the surface of the substrate 100, but also form a loose and porous structure on the surface of the substrate 100. Sandblasting refers to spraying abrasive onto the surface of the substrate 100 to form irregularly distributed pits on the surface of the substrate 100. Frosting refers to grinding the surface of the substrate 100 with an abrasive medium to create a certain degree of unevenness on the surface of the substrate 100. It is understood that irregular undulating structures can be formed on the surface of the substrate 100 through plasma treatment, laser irradiation, sandblasting, or frosting. Imprinting refers to using a mold or other medium to form a specific pattern on the surface of the substrate 100. Imprinting can form regular or irregular undulating structures.

[0071] The substrate 100 may be placed in a sputtering chamber to facilitate the subsequent process of preparing a metal layer.

[0072] In step S2 , vanadium metal is prepared by sputtering on the substrate 100 to form a vanadium metal layer 111 .

[0073] It is understood that a vanadium metal target can be used as a target material in a sputtering device, and the vanadium metal target can be bombarded to be deposited on the substrate 100 to obtain vanadium metal and form a vanadium metal layer 111 .

[0074] In some examples of this embodiment, before sputtering vanadium metal, the temperature of the substrate 100 can be controlled to be 25°C to 380°C. Further, the temperature of the substrate 100 can be controlled to be 25°C to 300°C. Even further, the temperature of the substrate 100 can be controlled to be 25°C to 100°C. It is understood that the material of the substrate 100 should ensure that it does not melt or undergo other chemical reactions when heated.

[0075] In some examples of this embodiment, a longer substrate 100 may be used. For example, the length of the substrate 100 may be 1 m to 10,000 m. During the actual sputtering process, the substrate 100 may be gradually moved while the vanadium metal is being sputtered, so that the substrate 100 gradually passes through the deposition area, thereby forming a continuous vanadium metal layer 111 on the substrate 100.

[0076] In some examples of this embodiment, the length of the substrate 100 may be 1 m, 100 m, 1000 m, 3000 m, 5000 m, or 10000 m. The length of the substrate 100 may also be in a range between any two of the above lengths.

[0077] During the sputtering process, the vanadium metal will be accelerated and have a certain initial kinetic energy, which leads to the natural existence of nano-scale to micro-scale micropores in the vanadium metal layer 111 formed by sputtering, so that the vanadium metal layer 111 has a larger specific surface area, which helps to increase the diffusion rate of hydrogen atoms during the hydrogen storage process.

[0078] In some examples of this embodiment, in the step of sputtering to prepare the vanadium metal layer 111, the sputtering power density can be controlled to be 10W / cm 2 ~20W / cm 2 For example, in the step of sputtering the vanadium metal layer 111, the sputtering power density can be controlled to be 10W / cm 2 , 12W / cm 2 、14W / cm 2 、16W / cm 2 、18W / cm 2 or 20W / cm 2The sputtering power density can also be controlled within the range between any two power densities mentioned above. By controlling the power density of the vanadium metal layer 111 to be 10W / cm 2 ~20W / cm 2 , which can ensure the uniformity of the vanadium metal layer 111 while making the vanadium metal layer 111 have an appropriate amount of micropores.

[0079] In some examples of this embodiment, the thickness of the sputtered vanadium metal layer 111 can be controlled to be 5 nm to 100 nm. It is understood that the thickness of the vanadium metal layer 111 can be controlled by controlling the sputtering time.

[0080] In step S3 , niobium metal is prepared by sputtering on the vanadium metal layer 111 to form a niobium metal layer 112 .

[0081] It is understood that a niobium metal target may be used as a target material in a sputtering device, and the niobium metal target may be bombarded to deposit on the substrate 100 , thereby obtaining niobium metal and forming the niobium metal layer 112 .

[0082] In some examples of this embodiment, step S2 and step S3 can be performed in two different deposition chambers, and a transport track can be provided between the two deposition chambers. During the actual preparation process, the substrate 100 is placed on the transport track and transported from the deposition chamber for sputtering vanadium metal to the deposition chamber for sputtering niobium metal.

[0083] In some examples of this embodiment, before sputtering niobium metal, the temperature of the substrate 100 can be controlled to be 25°C to 380°C. Furthermore, the temperature of the substrate 100 can be controlled to be 25°C to 300°C. Furthermore, the temperature of the substrate 100 can be controlled to be 25°C to 100°C. It is understood that the material of the substrate 100 should ensure that it does not melt or undergo other chemical reactions when heated.

[0084] During the sputtering process, the niobium metal particles are accelerated and have a certain initial kinetic energy, which enables the niobium metal particles to bombard and embed into the surface layer of the vanadium metal layer 111 , further causing lattice defects in the vanadium metal layer 111 .

[0085] In some examples of this embodiment, in the step of sputtering to prepare niobium metal, the sputtering power density can be controlled to be 15W / cm 2 ~30W / cm 2 Furthermore, the sputtering power density during the sputtering of niobium metal is higher than that during the sputtering of vanadium metal. Controlling the sputtering power density during the sputtering of niobium metal to a higher level helps further embed the niobium metal into the already prepared vanadium metal layer 111 and forms more micropores on the surfaces of the already prepared vanadium metal layer 111 and the niobium metal layer 112.

[0086] In some examples of this embodiment, during the step of sputtering the niobium metal layer 112, the sputtering power density may be controlled to be 15 W / cm 2 、18W / cm 2 , 21W / cm 2 , 25W / cm 2 , 28W / cm 2 or 30W / cm 2 The sputtering power density can also be controlled within the range between any two of the above power densities.

[0087] In some examples of this embodiment, the thickness of the sputtered niobium metal layer 112 can be controlled to be 5 nm to 100 nm. It is understood that the thickness of the niobium metal layer 112 can be controlled by controlling the sputtering time.

[0088] It can be understood that through steps S2 to S3 , a vanadium metal layer 111 and a niobium metal layer 112 can be prepared, and the niobium metal layer 112 and the vanadium metal layer 111 are sequentially stacked on the substrate 100 .

[0089] In step S4 , vanadium metal is sputtered multiple times and niobium metal is sputtered multiple times to form a multi-layer niobium metal layer 112 and a multi-layer vanadium metal layer 111 , respectively.

[0090] It will be appreciated that during the sputtering process, vanadium metal and niobium metal are sputtered alternately. When sputtering vanadium metal to form the vanadium metal layer 111, the vanadium metal can be sputtered onto the surface of the already prepared niobium metal layer 112. When sputtering niobium metal to form the niobium metal layer 112, the niobium metal can be sputtered onto the surface of the already prepared vanadium metal layer 111. Furthermore, adjacent niobium metal layers 112 and vanadium metal layers 111 are in contact with each other.

[0091] In some examples of this embodiment, when sputtering vanadium metal and niobium metal, the temperature of the substrate 100 may be controlled to be 25° C. to 100° C.

[0092] In some examples of this embodiment, when alternately sputtering multiple times of vanadium metal and multiple times of niobium metal, the sputtering power density of the vanadium metal can be 10 W / cm 2 ~20W / cm 2 The power density of each sputtering of the vanadium metal can be the same or different, and this can be selected based on the actual performance of the vanadium metal layer 111 required.

[0093] In some examples of this embodiment, when alternately sputtering multiple times of vanadium metal and multiple times of niobium metal, the sputtering power density of the niobium metal can be 15 W / cm 2 ~30W / cm 2The power density of each sputtering of the niobium metal can be the same or different, and this can be selected based on the actual performance of the desired niobium metal layer 112 .

[0094] It is understood that the specific thickness of the prepared vanadium metal layer 111 and the niobium metal layer 112 can be controlled by controlling the time of sputtering the vanadium metal and the niobium metal.

[0095] In some examples of this embodiment, the process of alternately sputtering vanadium metal and niobium metal may further include the following steps: introducing a gasifying agent into the deposition chamber to allow the gasifying agent to adhere to the previously prepared vanadium metal layer 111 or niobium metal layer 112, and then continuing to alternately sputter vanadium metal and niobium metal on the vanadium metal layer 111 or niobium metal layer 112 to which the gasifying agent is attached, and then heating the substrate 100 to volatilize the gasifying agent.

[0096] In the alternating sputtering process, the vaporizing agent is attached to the previously prepared vanadium metal layer 111 or niobium metal layer 112, and then the vanadium metal layer 111 and the niobium metal layer 112 are further prepared on the vanadium metal layer 111 or the niobium metal layer 112 before being vaporized. This allows the vaporizing agent to volatilize, and during the volatilization process, more micropores can be generated in the vanadium metal layer 111 and the niobium metal layer 112, thereby increasing the specific surface area of ​​the vanadium metal layer 111 and the niobium metal layer 112.

[0097] It can be understood that in some examples of this embodiment, the porosity of the composite hydrogen storage film material can be adjusted to 10% to 50% by controlling the sputtering power and the amount of the gasifying agent.

[0098] In some examples of this embodiment, between the step of introducing a gasifying agent into the deposition chamber and the step of volatilizing the gasifying agent, one or more vanadium metal layers 111 and one or more niobium metal layers 112 may be formed. Furthermore, between the step of introducing a gasifying agent into the deposition chamber and the step of volatilizing the gasifying agent, ten vanadium metal layers 111 and ten niobium metal layers 112 may be formed.

[0099] The gasifying agent can be a material that can adhere to the previously prepared metal layer and can be quickly removed by heating. This requires that the gasifying agent has a suitable evaporation temperature. In this embodiment, the gasifying agent can be water vapor. In other embodiments, the gasifying agent can also be other agents with suitable evaporation temperatures.

[0100] In some examples of this embodiment, in the step of heating the substrate 100 to volatilize the gasifying agent, the temperature of the substrate 100 may be controlled to be 120° C. to 200° C.

[0101] In some examples of this embodiment, the step of introducing a gasifying agent into the deposition chamber is performed after sputtering the vanadium metal, so that the gasifying agent adheres to the previously prepared vanadium metal layer 111. It will be understood that by adhering the gasifying agent to the vanadium metal layer 111, the subsequently prepared niobium metal layer 112 can cover the gasifying agent, thereby minimizing the impact of the introduction of the gasifying agent on the performance of the vanadium metal layer 111.

[0102] In some examples of this embodiment, in the step of alternately sputtering vanadium metal and niobium metal, the metal sputtered last is niobium metal, so that the layer farthest from the substrate 100 in the hydrogen storage layer 110 is the niobium metal layer 112 .

[0103] It can be understood that through steps S1 to S4, the hydrogen storage composite coiled material shown in Figure 1 can be prepared. Furthermore, after the hydrogen storage layer 110 is prepared, the substrate 100 and the hydrogen storage layer 110 can be wound as a whole to form a composite hydrogen storage film material with a multi-layer rolled structure as shown in Figure 2.

[0104] Compared to a single vanadium metal, by providing a niobium metal layer alternating with the vanadium metal layer, an alloy-like structure can be formed at the interface between the niobium metal layer and the vanadium metal layer, and lattice defects can occur in the vanadium metal layer. Furthermore, the vanadium metal layer and the niobium metal layer that are alternately stacked are provided on a substrate and form a multi-layer curled structure as a whole, which can not only effectively increase the overall effective hydrogen absorption area of ​​the hydrogen storage layer, but also cause the vanadium metal layer close to the substrate to undergo structural deformation through the curled structure, thereby increasing the overall lattice defects. On the one hand, this can reduce the stability of vanadium hydride, making hydrogen easier to absorb and release. On the other hand, the niobium metal layer can also be used to support the vanadium metal layer to maintain the overall structural stability of the vanadium metal layer, prevent the vanadium metal layer from de-powdering due to volume changes, and thus improve the reversibility of hydrogen storage in the vanadium metal layer.

[0105] Furthermore, the present disclosure also provides a hydrogen storage tank, which includes a tank body and a composite hydrogen storage film material as described in the above embodiment, wherein the composite hydrogen storage film material is disposed in the tank body.

[0106] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0107] The above embodiments merely illustrate 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 patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A composite hydrogen storage membrane material, comprising: A substrate and a hydrogen storage layer arranged on the substrate, wherein the substrate is a flexible substrate, the substrate and the hydrogen storage layer have a multi-layer curled structure as a whole, the hydrogen storage layer covers the substrate, the hydrogen storage layer includes multiple layers of vanadium metal layers and multiple layers of niobium metal layers, the vanadium metal layers and the niobium metal layers are alternately stacked on the substrate in sequence, and adjacent vanadium metal layers and niobium metal layers are in contact with each other. 2 . The composite hydrogen storage membrane material according to claim 1 , wherein the thickness of the vanadium metal layer is 5 nm to 100 nm. 3 . The composite hydrogen storage film material according to claim 1 , wherein the thickness of the niobium metal layer is 1 nm to 10 nm. 4 . The composite hydrogen storage membrane material according to claim 1 , wherein the hydrogen storage layer has micropores, and the porosity of the hydrogen storage layer is 10% to 50%. 5 . The composite hydrogen storage film material according to claim 4 , wherein in the hydrogen storage layer, the layer farthest from the substrate is the niobium metal layer. 6 . The composite hydrogen storage membrane material according to claim 1 , wherein the total thickness of the hydrogen storage layer is 100 nm to 5000 nm. 7 . The composite hydrogen storage membrane material according to claim 1 , wherein in the hydrogen storage layer, the total number of the vanadium metal layers is 20 to 500. 8 . The composite hydrogen storage film material according to claim 1 , wherein in the hydrogen storage layer, the total number of the niobium metal layers is 20 to 500. 9 . The composite hydrogen storage film material according to claim 1 , wherein the hydrogen storage layer is disposed on both opposite side surfaces of the substrate.

10. A method for preparing a composite hydrogen storage membrane material, the composite hydrogen storage membrane material comprising: A substrate and a hydrogen storage layer disposed on the substrate, wherein the substrate is a flexible substrate, the substrate and the hydrogen storage layer as a whole have a multi-layer curled structure, the hydrogen storage layer covers the substrate, the hydrogen storage layer comprises a multi-layer vanadium metal layer and a multi-layer niobium metal layer, the vanadium metal layer and the niobium metal layer are alternately stacked on the substrate in sequence, and the adjacent vanadium metal layers are in contact with each other; The preparation method comprises the following steps: providing the substrate; The vanadium metal is sputtered multiple times and the niobium metal is sputtered multiple times on the substrate to form multiple layers of the niobium metal layer and multiple layers of the vanadium metal layer respectively. During the sputtering process, the vanadium metal and the niobium metal are sputtered alternately. 11 . The method for preparing a composite hydrogen storage film material according to claim 10 , wherein when niobium metal is sputtered on the prepared vanadium metal layer, the sputtering power is controlled so that niobium atoms are embedded in the vanadium metal layer.

12. The method for preparing a composite hydrogen storage film material according to claim 11, wherein in the step of sputtering vanadium metal, the sputtering power density is controlled to be 10 W / cm 2 ~20W / cm 2 .

13. The method for preparing a composite hydrogen storage film according to claim 11 or 12, wherein in the step of sputtering niobium metal, the sputtering power density is controlled to be 15 W / cm 2 ~30W / cm 2 . 14 . The method for preparing a composite hydrogen storage film material according to claim 10 , wherein in the step of sputtering vanadium metal on the substrate, the thickness of each vanadium metal layer is controlled to be 5 nm to 100 nm. 15 . The method for preparing a composite hydrogen storage film material according to claim 10 , wherein in the step of sputtering niobium metal on the substrate, the thickness of each niobium metal layer is controlled to be 1 nm to 10 nm. 16 . The method for preparing a composite hydrogen storage membrane material according to claim 10 , wherein in the hydrogen storage layer, the total number of the vanadium metal layers is 20 to 500. 17 . The method for preparing a composite hydrogen storage membrane material according to claim 10 , wherein in the hydrogen storage layer, the total number of the niobium metal layers is 20 to 500. 18 . The composite hydrogen storage membrane material according to claim 10 , wherein the hydrogen storage layer has micropores, and the porosity of the hydrogen storage layer is 10% to 50%.

19. The method for preparing a composite hydrogen storage film material according to claim 18, further comprising the following steps during the process of sputtering vanadium metal multiple times and sputtering niobium metal multiple times: Introducing a gasifying agent into a deposition chamber so that the gasifying agent adheres to the previously prepared vanadium metal layer or niobium metal layer; Continue to alternately sputter vanadium metal and niobium metal on the vanadium metal layer or the niobium metal layer to which the gasification agent is attached, and then perform a temperature-raising treatment on the substrate to volatilize the gasification agent. 20 . The method for preparing a composite hydrogen storage film material according to claim 19 , wherein the step of introducing a gasifying agent into the deposition chamber is performed after sputtering vanadium metal, so that the gasifying agent adheres to the previously prepared vanadium metal layer.

21. The method for preparing a composite hydrogen storage membrane material according to claim 19 or 20, wherein the gasifying agent is water.

22. A hydrogen storage tank comprising a tank body and the composite hydrogen storage film material according to any one of claims 1 to 9, wherein the composite hydrogen storage film material is arranged in the tank body.

Images