Composite hydrogen storage material with high poisoning resistance and preparation method thereof

Abstract

The invention relates to the technical field of hydrogen storage materials, in particular to a composite hydrogen storage material with poison resistance and a preparation method of the composite hydrogen storage material. The composite hydrogen storage material comprises a ferrotitanium hydrogen storage alloy and cerium oxide, and the cerium oxide completely coats the surface of the ferrotitanium hydrogen storage alloy. The composite hydrogen storage material has excellent anti-poisoning performance and hydrogen absorption dynamic performance, can resist poisoning of various foreign gases (CH4, O2, CO and CO2), and reduces the poisoning influence of the foreign gases in hydrogen on the composite hydrogen storage material; the raw materials for preparing the composite hydrogen storage material are wide in source, and the composite hydrogen storage material has the advantage of low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage materials, and particularly to a composite hydrogen storage material with anti-poisoning performance and a preparation method thereof. Background Art

[0002] Due to its rich reserves, high calorific value, and pollution-free characteristics, hydrogen is regarded as the clean energy carrier with the most development potential in the 21st century. However, the storage and transportation of hydrogen have become important factors restricting the development of hydrogen energy. Therefore, it is particularly important to develop safe and efficient hydrogen storage materials.

[0003] At present, solid-state hydrogen storage materials have become a research hotspot in current hydrogen storage materials due to their advantages such as high hydrogen storage capacity, cyclic reversibility, and use safety. Among them, the titanium-iron (TiFe) hydrogen storage alloy is particularly prominent. It can achieve a high hydrogen storage density under mild conditions (25 - 40 °C) and an appropriate platform pressure (0.3 - 1.5 MPa), and is considered one of the most promising solid-state hydrogen storage materials. However, during the long-term use of the titanium-iron (TiFe) hydrogen storage alloy, impurity gases (such as O2, CO, CO2, N2, etc.) in hydrogen will have a poisoning effect on the titanium-iron (TiFe) hydrogen storage alloy (the impurity gases will form metal oxides, hydroxides, or carbon oxides on the surface of the titanium-iron hydrogen storage alloy, thus causing surface poisoning), resulting in a decline in the hydrogen storage capacity of the titanium-iron hydrogen storage alloy, and seriously affecting the service life of the titanium-iron (TiFe) hydrogen storage alloy.

[0004] Chinese patent technology with the publication number CN 115744815 A discloses a composite hydrogen storage material with the ability to resist impurity gas poisoning and a preparation method thereof. By mixing a rare-earth hydrogen storage alloy with MXene material and then carrying out ball milling, a composite hydrogen storage material with excellent anti-impurity gas poisoning ability can be prepared. However, the raw material cost of using MXene material in this invention is relatively high and the preparation process of MXene material is complex, making it difficult to achieve large-scale production; moreover, the composite hydrogen storage material in this invention can only resist CO gas poisoning, and its anti-poisoning performance is single.

[0005] Therefore, developing a low-cost titanium-iron alloy composite hydrogen storage material that can resist poisoning by multiple impurity gases is an urgent problem to be solved in this field. Summary of the Invention

[0006] The present invention provides a composite hydrogen storage material with high anti-poisoning performance. The composite hydrogen storage material includes a titanium-iron hydrogen storage alloy and cerium oxide, and the cerium oxide completely coats the surface of the titanium-iron hydrogen storage alloy. The raw materials are widely sourced and have the advantage of low cost. Moreover, the composite hydrogen storage material can resist poisoning by various impurity gases (CH4, O2, CO, CO2). After multiple hydrogen absorption and desorption cycles with impurity-containing gases, the attenuation of the hydrogen storage capacity of the composite hydrogen storage material is significantly reduced, and it has excellent anti-poisoning performance and hydrogen absorption kinetic performance.

[0007] The present invention also provides a preparation method of a composite hydrogen storage material with high anti-poisoning performance. Through this preparation method, a composite hydrogen storage material with low cost, excellent anti-poisoning performance and hydrogen absorption kinetic performance can be obtained.

[0008] In a first aspect of the present invention, there is provided a composite hydrogen storage material with high anti-poisoning performance. The composite hydrogen storage material includes a titanium-iron hydrogen storage alloy and cerium oxide, and the cerium oxide completely coats the surface of the titanium-iron hydrogen storage alloy.

[0009] For the composite hydrogen storage material with high anti-poisoning performance as described above, the cerium oxide includes cerium oxide.

[0010] For the composite hydrogen storage material with high anti-poisoning performance as described above, in the composite hydrogen storage material, the mass ratio of the titanium-iron hydrogen storage alloy to the cerium oxide is 1:(0.05 - 0.5).

[0011] In a second aspect of the present invention, there is provided a preparation method of the composite hydrogen storage material with high anti-poisoning performance as described above, including the following steps:

[0012] Prepare a titanium-iron hydrogen storage alloy;

[0013] Perform vacuum activation treatment on the titanium-iron hydrogen storage alloy to obtain the titanium-iron hydrogen storage alloy after vacuum activation treatment;

[0014] Mix the titanium-iron hydrogen storage alloy after vacuum activation treatment with cerium oxide to obtain a mixed material;

[0015] Perform mechanical ball milling treatment on the mixed material to obtain the composite hydrogen storage material.

[0016] For the preparation method of the composite hydrogen storage material with high anti-poisoning performance as described above, performing mechanical ball milling treatment on the mixed material includes:

[0017] Put the mixed material into a ball milling tank and put in ball milling beads. At room temperature, install the ball milling tank on a ball mill, set the ball milling speed to 300 - 500 r / min, and perform mechanical ball milling treatment using a ball milling process with a ball milling time of 10 min and a rest time of 10 min. The total ball milling time is 10 - 30 min.

[0018] The preparation method of the composite hydrogen storage material with high poisoning resistance as described above, wherein the mass ratio of the mixed material to the ball milling beads is 1:(40 - 80).

[0019] The preparation method of the composite hydrogen storage material with high poisoning resistance as described above, wherein the diameter of the ball milling beads is at least one of 3mm, 6mm, and 8mm.

[0020] The preparation method of the composite hydrogen storage material with high poisoning resistance as described above, wherein the vacuum-activated titanium-iron hydrogen storage alloy and cerium oxide are mixed to obtain a mixed material, including:

[0021] The vacuum-activated titanium-iron hydrogen storage alloy and cerium oxide are mixed evenly under the conditions of pure argon with a purity greater than 99.99% and water vapor and oxygen concentrations lower than 0.01 ppm to obtain a mixed material.

[0022] The preparation method of the composite hydrogen storage material with high poisoning resistance as described above, wherein the preparation of the titanium-iron hydrogen storage alloy includes:

[0023] Under the protection of an argon atmosphere, a mixture of titanium and iron is subjected to vacuum arc melting, and the titanium-iron hydrogen storage alloy is obtained after cooling.

[0024] The preparation method of the composite hydrogen storage material with high poisoning resistance as described above, wherein the molar ratio of titanium to iron is 1.1:0.9.

[0025] The composite hydrogen storage material with high poisoning resistance provided by the present invention, wherein the composite hydrogen storage material includes a titanium-iron hydrogen storage alloy and cerium oxide, and the cerium oxide completely coats the surface of the titanium-iron hydrogen storage alloy. This composite hydrogen storage material can resist poisoning by various impurity gases (CH4, O2, CO, CO2). After multiple hydrogen absorption and desorption cycles with impurity gases, the hydrogen storage capacity attenuation of the composite hydrogen storage material is significantly reduced, and it has excellent poisoning resistance and hydrogen absorption kinetic performance; moreover, the raw materials used to prepare this composite hydrogen storage material are widely available and have the advantage of low cost.

[0026] The preparation method of the composite hydrogen storage material with high poisoning resistance provided by the present invention can obtain a composite hydrogen storage material with excellent poisoning resistance and hydrogen absorption kinetic performance through this preparation method. This preparation method is simple, easy to operate, the raw materials are easy to obtain, and it has the advantage of low cost, and is suitable for wide promotion and use. Description of the Drawings

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 This is the SEM image of the composite hydrogen storage material in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material in Comparative Example 1. Among them, Figure 1 (a) is the SEM of the titanium-iron hydrogen storage alloy material in Comparative Example 1, Figure 1 (b) is the SEM image of the composite hydrogen storage material in Example 1;

[0029] Figure 2 This is the transmission electron microscope image of the composite hydrogen storage material in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material in Comparative Example 1. Among them, Figure 2 (a) is the high-angle annular dark field (HAADF) image of the titanium-iron hydrogen storage alloy material in Comparative Example 1, Figure 2 (b) is the high-resolution transmission electron microscope (HRTEM) image of the titanium-iron hydrogen storage alloy material in Comparative Example 1, Figure 2 (c) is the HAADF image of the composite hydrogen storage material in Example 1, Figure 2 (d) is the HRTEM image of the composite hydrogen storage material in Example 1;

[0030] Figure 3 This is the XRD pattern of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1;

[0031] Figure 4 This is the X-ray photoelectron spectroscopy of the titanium-iron hydrogen storage alloy material in Comparative Example 1 of the present invention;

[0032] Figure 5 This is the X-ray photoelectron spectroscopy of the composite hydrogen storage material in Example 1 of the present invention;

[0033] Figure 6 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 after 10 cycles of hydrogen absorption and desorption in pure hydrogen. Among them, Figure 6 (a) is the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 after 10 cycles of hydrogen absorption and desorption in pure hydrogen, Figure 6(b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 after 10 cycles of hydrogen absorption and desorption in pure hydrogen;

[0034] Figure 7 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and after 10 cycles of hydrogen absorption and desorption in CH4 + H2 (methane). Among them, Figure 7 (a) is the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Example 1 after 10 cycles of hydrogen absorption and desorption in CH4 + H2 (methane), Figure 7 (b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 after 10 cycles of hydrogen absorption and desorption in CH4 + H2 (methane);

[0035] Figure 8 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and after 10 cycles of hydrogen absorption and desorption in COx + H2 (COx). Among them, Figure 8 (a) is the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) after 10 cycles of hydrogen absorption and desorption in COx + H2 (COx), Figure 8 (b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) after 10 cycles of hydrogen absorption and desorption in COx + H2 (COx);

[0036] Figure 9 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and after 5 cycles of hydrogen absorption and desorption in O2 + H2 (oxygen). Among them, Figure 9 (a) is the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) after 5 cycles of hydrogen absorption and desorption in O2 + H2 (oxygen), Figure 9 (b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9The hydrogen absorption kinetic curve obtained after the composite hydrogen storage material (TiFe

[0037] Figure 10 -CeO2) in Example 1 of the present invention cycles hydrogen absorption and desorption in O2 + H2 (oxygen) 5 times. 0.9 -CeO2) and the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and the comparison diagram of the hydrogen absorption kinetic performance after cycling hydrogen absorption and desorption 10 times in different impurity gases;

[0038] Figure 11 The hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 2 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after cycling hydrogen absorption and desorption in O2 + H2 (oxygen) 5 times.

[0039] Figure 12 The hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 3 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after cycling hydrogen absorption and desorption in O2 + H2 (oxygen) 5 times.

[0040] Figure 13 The hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 4 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after cycling hydrogen absorption and desorption in O2 + H2 (oxygen) 5 times.

[0041] Figure 14 The hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 5 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after cycling hydrogen absorption and desorption in O2 + H2 (oxygen) five times.

[0042] Figure 15 The hydrogen storage capacity of the composite hydrogen storage materials in Examples 1-5 of the present invention and the titanium-iron hydrogen storage alloy material in Comparative Example 1 in pure hydrogen, the hydrogen storage capacity after cycling hydrogen absorption and desorption in O2 + H2 (oxygen) 5 times, and the capacity decay rate after cycling hydrogen absorption and desorption in O2 + H2 (oxygen) 5 times. Detailed implementation manners

[0043] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, rather than all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0044] In the embodiments of the present invention, if no specific technology or conditions are indicated, they shall be in accordance with the technologies or conditions described in the literature in this field or in accordance with the product specifications. For reagents or instruments without indicating the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0045] In the present invention, the term "at least one" means one or more, and "a plurality" means two or more.

[0046] In the first aspect of the present invention, a composite hydrogen storage material with high anti-poisoning performance is provided. The composite hydrogen storage material includes a titanium-iron hydrogen storage alloy and a cerium oxide, and the cerium oxide completely coats the surface of the titanium-iron hydrogen storage alloy.

[0047] Specifically, in the present invention, by coating the cerium oxide on at least part of the surface of the titanium-iron hydrogen storage alloy, a composite hydrogen storage material is obtained. This composite hydrogen storage material can resist poisoning by various impurity gases (CH4, O2, CO, CO2). After multiple hydrogen absorption and desorption cycles with impurity gases, the attenuation of the hydrogen storage capacity of the composite hydrogen storage material is significantly reduced, and it has excellent anti-poisoning performance and hydrogen absorption kinetic performance; moreover, the raw materials used for preparing this composite hydrogen storage material are widely available and have the advantage of low cost.

[0048] In a specific embodiment, the above-mentioned cerium oxide includes cerium oxide.

[0049] When the above-mentioned cerium oxide is cerium oxide (CeO2), in an environment of hydrogen or impurity gases, the cerium oxide in this composite hydrogen storage material can achieve reversible absorption and release of lattice oxygen through the dynamic oxygen vacancy mechanism, and the oxygen atoms in the crystal structure of cerium oxide have high mobility and are easily detached from the lattice. Therefore, hydrogen atoms can not only quickly diffuse into the cerium oxide lattice, but also have a strong electronic interaction with it. And the Ce element in cerium oxide (CeO2) can act as a strong oxygen scavenger, which is beneficial to improving the hydrogen absorption kinetic performance and anti-poisoning performance of this composite hydrogen storage material.

[0050] In a specific embodiment, in the above-mentioned composite hydrogen storage material, the mass ratio of the titanium-iron hydrogen storage alloy to the cerium oxide is 1:(0.05 - 0.5), and preferably 1:(0.1 - 0.3).

[0051] When the parameter of the mass ratio of the titanium-iron hydrogen storage alloy to the cerium oxide in the above-mentioned composite hydrogen storage material is within the above range, the prepared composite hydrogen storage material has excellent anti-poisoning performance and hydrogen absorption kinetic performance, can resist poisoning by various impurity gases (CH4, O2, CO, CO2), reduce the poisoning effect of impurity gases in hydrogen on it, and after multiple hydrogen absorption and desorption cycles with impurity gases, the attenuation of the hydrogen storage capacity of the composite hydrogen storage material is significantly reduced.

[0052] Exemplarily, in the above composite hydrogen storage material, the mass ratio of the titanium-iron hydrogen storage alloy to cerium oxide can be any one of 1:0.1, 1:0.15, 1:0.2, 1:0.3 and the range composed of any two of them.

[0053] In a second aspect, the present invention provides a method for preparing the above composite hydrogen storage material with high anti-poisoning performance, comprising the following steps:

[0054] Prepare a titanium-iron hydrogen storage alloy;

[0055] Perform vacuum activation treatment on the titanium-iron hydrogen storage alloy to obtain the titanium-iron hydrogen storage alloy after vacuum activation treatment;

[0056] Mix the titanium-iron hydrogen storage alloy after vacuum activation treatment with cerium oxide to obtain a mixed material;

[0057] Perform mechanical ball milling treatment on the mixed material to obtain the composite hydrogen storage material.

[0058] The object of the preparation in the present invention is a composite hydrogen storage material. Specifically, the present invention first prepares a titanium-iron hydrogen storage alloy, and then performs vacuum activation treatment on the titanium-iron hydrogen storage alloy to obtain the titanium-iron hydrogen storage alloy after vacuum activation treatment. The titanium-iron hydrogen storage alloy is very sensitive to air and can form an oxide layer on the alloy surface, which hinders hydrogen from entering the interior of the alloy. The vacuum activation treatment is to promote the first hydrogen absorption and remove the oxide layer and impurities attached to the surface of the titanium-iron hydrogen storage alloy; then mix the titanium-iron hydrogen storage alloy after vacuum activation treatment with cerium oxide evenly to obtain a mixed material; finally, perform mechanical ball milling treatment on the mixed material to obtain a composite hydrogen storage material with excellent anti-poisoning performance and hydrogen absorption kinetics performance. Defects and nanocrystals are easily generated through mechanical ball milling treatment, and the introduction of these defects and nanocrystals provides more active sites for dehydrogenation and re-hydrogenation of the material, shortening the diffusion path of hydrogen, thereby improving the hydrogen absorption and desorption kinetics performance.

[0059] In a specific embodiment, performing mechanical ball milling treatment on the above mixed material includes:

[0060] Put the mixed material into a ball milling tank and put in ball milling beads. At room temperature, install the ball milling tank on a ball mill, set the ball milling speed to 400 r / min, and perform mechanical ball milling treatment using a ball milling process with a ball milling time of 10 min and a rest time of 10 min. The total ball milling time is 10 - 30 min.

[0061] In the present invention, the purpose of the rest is to avoid overheating of the mixed material during the mechanical ball milling treatment.

[0062] When performing mechanical ball milling treatment using the above process, it is beneficial to prepare a composite hydrogen storage material with excellent anti-poisoning performance.

[0063] In a specific embodiment, the mass ratio of the above-mentioned mixed material to the above-mentioned ball milling beads is 1:(40 - 80).

[0064] When the parameter of the mass ratio of the mixed material to the ball milling beads is within the above range, it is beneficial to prepare a composite hydrogen storage material with excellent anti-poisoning performance. After multiple hydrogen absorption and desorption cycles of hydrogen containing impurity gases, the attenuation amount of the hydrogen storage capacity of the composite hydrogen storage material decreases, and the hydrogen absorption kinetic performance and anti-poisoning performance are improved.

[0065] Exemplarily, the mass ratio of the mixed material to the ball milling beads can be any one of 1:40, 1:50, 1:60, 1:70, 1:80 and the range composed of any two of them.

[0066] When the parameter of the mass ratio of the mixed material to the ball milling beads is within the above range, it is beneficial to prepare a composite hydrogen storage material with more excellent anti-poisoning performance. After multiple hydrogen absorption and desorption cycles of hydrogen containing impurity gases, the attenuation amount of the hydrogen storage capacity of the composite hydrogen storage material further decreases, and the hydrogen absorption kinetic performance and anti-poisoning performance are further improved.

[0067] The material of the above-mentioned ball milling beads is a conventional material. For example, the above-mentioned ball milling beads are stainless steel ball milling beads.

[0068] In a specific embodiment, the diameter of the above-mentioned ball milling beads is at least one of 3mm, 6mm, and 8mm.

[0069] When the diameter of the ball milling beads is at least one of 3mm, 6mm, and 8mm, the mixed material can be sufficiently mechanically ball milled, so that cerium oxide is uniformly coated on the surface of the titanium-iron hydrogen storage alloy, and a composite hydrogen storage material with excellent anti-poisoning performance is obtained.

[0070] In a specific embodiment, the above-mentioned titanium-iron hydrogen storage alloy after vacuum activation treatment is mixed with the above-mentioned cerium oxide to obtain a mixed material, including:

[0071] The titanium-iron hydrogen storage alloy after vacuum activation treatment and cerium oxide are mixed evenly under the conditions of pure argon with a purity greater than 99.99% and the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material.

[0072] The titanium-iron hydrogen storage alloy after vacuum activation treatment and cerium oxide are mixed evenly under the conditions of pure argon with a purity greater than 99.99% and the concentrations of water vapor and oxygen lower than 0.01 ppm, so that the surface of the material will not be oxidized again to form an oxide layer, which is beneficial to the subsequent preparation of a composite hydrogen storage material with excellent hydrogen storage performance.

[0073] In a specific embodiment, the above-mentioned preparation of the titanium-iron hydrogen storage alloy includes:

[0074] Under the protection of an argon atmosphere, a mixture of titanium and iron is subjected to vacuum arc melting, and after cooling, a titanium-iron hydrogen storage alloy is obtained.

[0075] The present invention does not particularly limit the specific equipment for vacuum arc melting. Equipment well-known in the art can be used to perform vacuum arc melting on the mixture of titanium and iron. In some embodiments, the mixture of titanium and iron can be placed in a non-consumable vacuum arc melting furnace for vacuum arc melting.

[0076] The present invention does not particularly limit the specific number of times of vacuum arc melting, which can be selected according to actual needs. In some embodiments, in order to ensure the uniformity of the components in the titanium-iron hydrogen storage alloy, the mixture of titanium and iron can be placed in a non-consumable vacuum arc melting furnace for vacuum arc melting 3-5 times.

[0077] In a specific embodiment, the molar ratio of the above-mentioned titanium to the above-mentioned iron is 1.1:0.9.

[0078] When the molar ratio of titanium to iron is 1.1:0.9, a titanium-iron hydrogen storage alloy can be prepared. By compounding this titanium-iron hydrogen storage alloy with cerium oxide, a composite hydrogen storage material with cerium oxide completely coating the surface of the titanium-iron hydrogen storage alloy can be prepared. This composite hydrogen storage material has excellent anti-poisoning performance and hydrogen absorption kinetic performance.

[0079] Hereinafter, the solutions of the present invention will be introduced in detail through specific examples.

[0080] Example 1

[0081] The preparation method of the composite hydrogen storage material provided in this example includes the following steps:

[0082] (1) Prepare a titanium-iron hydrogen storage alloy

[0083] Raw materials are weighed according to the molar ratio of titanium to iron of 1.1:0.9; under the protection of an argon atmosphere, the weighed raw materials (i.e., the mixture of titanium and iron) are placed in a non-consumable vacuum arc melting furnace for vacuum arc melting 5 times, and then cooled to room temperature with the furnace to obtain a titanium-iron (TiFe) hydrogen storage alloy.

[0084] (2) Perform vacuum activation treatment on the titanium-iron hydrogen storage alloy

[0085] Use sandpaper to polish and remove the oxide layer on the surface of the titanium-iron hydrogen storage alloy, and then in a glove box filled with pure argon (99.99%) and with the concentrations of water vapor and oxygen lower than 0.01 ppm, use a mortar to crush and grind the titanium-iron hydrogen storage alloy through a sieve (100 mesh) to obtain titanium-iron hydrogen storage alloy powder;

[0086] Put the titanium-iron hydrogen storage alloy powder into the sample chamber of a Sieverts-type hydrogen storage tester for vacuum activation treatment twice to obtain the titanium-iron hydrogen storage alloy after vacuum activation treatment. The specific process of the vacuum activation treatment is as follows: First, evacuate to 1×10 -4 MPa at 25°C for 15 minutes to remove surface adsorbed impurities, then heat up to 400°C at a rate of 10°C / min, evacuate for 1 hour and cool to room temperature, and then fill with 5 MPa high-purity hydrogen (purity > 99.999%). Next, carry out activation at 400°C for 2 hours. After the titanium-iron hydrogen storage alloy powder is saturated with hydrogen absorption, evacuate for 1 hour and cool to room temperature to obtain the titanium-iron hydrogen storage alloy after vacuum activation treatment.

[0087] (3) Preparation of the composite hydrogen storage material

[0088] Mix 2 g of the titanium-iron hydrogen storage alloy after vacuum activation treatment with 0.2 g of cerium oxide (CeO2) evenly in a glove box filled with pure argon (99.99%) and with the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material;

[0089] Put 2.2 g of the mixed material into a ball milling tank and put 88 g of stainless steel ball milling beads with a diameter of 6 mm (ball-to-material ratio is 40:1). At room temperature, install the ball milling tank on the ball mill, set the ball milling speed to 400 r / min, and carry out mechanical ball milling treatment twice using a ball milling process with a ball milling time of 10 minutes and a rest time of 10 minutes. The total ball milling time is 20 minutes (min) to obtain the composite hydrogen storage material.

[0090] Example 2

[0091] The preparation method of the composite hydrogen storage material provided in this example is basically the same as that in Example 1, except that:

[0092] (3) Preparation of the composite hydrogen storage material

[0093] Mix 2 g of the titanium-iron hydrogen storage alloy after vacuum activation treatment with 0.2 g of cerium oxide (CeO2) evenly in a glove box filled with pure argon (99.99%) and with the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material;

[0094] Put 2.2 g of the mixed material into a ball milling tank and put 88 g of stainless steel ball milling beads with a diameter of 6 mm (ball-to-material ratio is 40:1). At room temperature, install the ball milling tank on the ball mill, set the ball milling speed to 400 r / min, and carry out mechanical ball milling treatment once using a ball milling process with a ball milling time of 10 minutes and a rest time of 10 minutes. The total ball milling time is 10 minutes to obtain the composite hydrogen storage material.

[0095] Example 3

[0096] The preparation method of the composite hydrogen storage material provided in this example is basically the same as that in Example 1, except that:

[0097] (3) Preparation of the composite hydrogen storage material

[0098] Mix 2 g of the vacuum-activated titanium-iron hydrogen storage alloy with 0.2 g of cerium oxide (CeO2) evenly in a glove box filled with pure argon (99.99%) and with the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material;

[0099] Put 2.2 g of the mixed material into a ball milling tank and add 176 g of stainless steel ball milling beads with a diameter of 6 mm (ball-to-material ratio is 80:1). At room temperature, place the ball milling tank on the ball mill, set the ball milling speed to 400 r / min, and perform mechanical ball milling treatment twice using a ball milling process with a ball milling time of 10 min and a rest time of 10 min. The total ball milling time is 20 min to obtain the composite hydrogen storage material.

[0100] Example 4

[0101] The preparation method of the composite hydrogen storage material provided in this example is basically the same as that in Example 1, except that:

[0102] (3) Preparation of the composite hydrogen storage material

[0103] Mix 2 g of the vacuum-activated titanium-iron hydrogen storage alloy with 0.2 g of cerium oxide (CeO2) evenly in a glove box filled with pure argon (99.99%) and with the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material;

[0104] Put 2.2 g of the mixed material into a ball milling tank and add 176 g of stainless steel ball milling beads with a diameter of 6 mm (ball-to-material ratio is 80:1). At room temperature, place the ball milling tank on the ball mill, set the ball milling speed to 400 r / min, and perform mechanical ball milling treatment three times using a ball milling process with a ball milling time of 10 min and a rest time of 10 min. The total ball milling time is 30 min to obtain the composite hydrogen storage material.

[0105] Example 5

[0106] The preparation method of the composite hydrogen storage material provided in this comparative example is basically the same as that in Example 1, except that:

[0107] (3) Preparation of the composite hydrogen storage material

[0108] Mix 2 g of the vacuum-activated titanium-iron hydrogen storage alloy with 1 g of cerium oxide (CeO2) evenly in a glove box filled with pure argon (99.99%) and with the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material;

[0109] Put 2.2 g of the mixed materials into a ball-milling tank and add 44 g of stainless steel ball-milling beads with a diameter of 6 mm (the ball-to-material ratio is 40:1). At room temperature, place the ball-milling tank on a ball mill, set the ball-milling speed to 400 r / min, and perform mechanical ball milling twice using a ball-milling process with a ball-milling time of 10 min and a rest time of 10 min. The total ball-milling time is 20 min to obtain the composite hydrogen storage material.

[0110] Comparative Example 1 (without adding cerium oxide)

[0111] The preparation method of the titanium-iron hydrogen storage alloy material provided in this comparative example includes the following steps:

[0112] (1) Prepare the titanium-iron hydrogen storage alloy

[0113] Weigh the raw materials of titanium and iron according to a molar ratio of 1.1:0.9; under the protection of an argon atmosphere, place the weighed raw materials (i.e., the mixture of titanium and iron) in a non-consumable vacuum arc melting furnace for vacuum arc melting 5 times, and cool it to room temperature with the furnace to obtain the titanium-iron hydrogen storage alloy.

[0114] (2) Prepare the titanium-iron hydrogen storage alloy material

[0115] Use sandpaper to polish and remove the surface oxide layer of the titanium-iron hydrogen storage alloy, and then in a glove box filled with pure argon (99.99%) and with the water vapor and oxygen concentrations lower than 0.01 ppm, crush and grind the titanium-iron hydrogen storage alloy with a mortar and sieve it (100 mesh) to obtain the titanium-iron hydrogen storage alloy powder;

[0116] Put the titanium-iron hydrogen storage alloy powder into the sample chamber of a Sieverts-type hydrogen storage tester for vacuum activation treatment twice to obtain the titanium-iron hydrogen storage alloy material; the specific process of the vacuum activation treatment is as follows: First, evacuate to 1×10 -4 MPa at 25°C for 15 min to remove the surface adsorbed impurities, then heat it to 400°C at a rate of 10°C / min, evacuate for 1 h and cool it to room temperature, and then fill it with 5 MPa high-purity hydrogen (purity > 99.999%). Then, perform activation at 400°C for 2 h. After the titanium-iron hydrogen storage alloy powder is saturated with hydrogen absorption, evacuate for 1 h and cool it to room temperature to obtain the titanium-iron hydrogen storage alloy material.

[0117] Performance testing

[0118] (1) Scanning electron microscope (SEM) testing

[0119] Perform scanning electron microscope (SEM) testing on the composite hydrogen storage material in Example 1 and the titanium-iron hydrogen storage alloy material in Comparative Example 1 respectively; Figure 1 These are the SEM diagrams of the composite hydrogen storage material in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material in Comparative Example 1, where Figure 1(a) is the SEM of the titanium-iron hydrogen storage alloy material in Comparative Example 1, Figure 1 (b) is the SEM image of the composite hydrogen storage material in Example 1.

[0120] From Figure 1 (a)-(b), it can be seen that compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the particle size of the composite hydrogen storage material in Example 1 is reduced, and it can be observed that the surface of the composite hydrogen storage material loses its original smooth and flat appearance, and fine particles of CeO2 are evenly dispersed on the surface.

[0121] (2) Transmission electron microscopy (TEM) test

[0122] The composite hydrogen storage material in Example 1 and the titanium-iron hydrogen storage alloy material in Comparative Example 1 were respectively tested by transmission electron microscopy (TEM); Figure 2 are the TEM images of the composite hydrogen storage material in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material in Comparative Example 1, where Figure 2 (a) is the high-angle annular dark field (HAADF) image of the titanium-iron hydrogen storage alloy material in Comparative Example 1, Figure 2 (b) is the high-resolution transmission electron microscopy (HRTEM) image of the composite hydrogen storage material in Comparative Example 1, Figure 2 (c) is the HAADF image of the composite hydrogen storage material in Example 1, Figure 2 (d) is the HRTEM image of the composite hydrogen storage material in Example 1.

[0123] According to Figure 2 (a)-(d), the lattice constants of TiFe(110), CeO2(200), CeO2(220) and CeO2(311) are 0.210 nm, 0.183 nm, 0.256 nm and 0.293 nm respectively, which proves that in the composite hydrogen storage material in Example 1 of the present invention, the oxide coated on the surface of the titanium-iron hydrogen storage alloy is CeO2.

[0124] (3) X-ray diffraction (XRD) test

[0125] The composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 and the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 were respectively tested by X-ray diffraction; Figure 3 are the XRD patterns of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1.

[0126] From Figure 3 it can be seen that compared with the titanium-iron hydrogen storage alloy material (TiFe 0.9) Compared with [specific comparison], the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 shows a wider peak, which means a reduction in the crystal size of the composite hydrogen storage material or the presence of microstrain. In the composite hydrogen storage material in Example 1 and the titanium-iron hydrogen storage alloy material in Comparative Example 1, there is a TiFe phase (PDF#97-018-1683, CsCl structure, space group Pm-3m). The diffraction peaks at 42.9°, 62.2°, and 78.5° correspond to the (110), (200), and (211) crystal planes respectively. The peak values of the composite hydrogen storage material in Example 1 indicate the presence of a CeO2 phase (PDF#97-062-1705, fluorite structure, space group Fm-3m). The diffraction peaks at 28.6° and 47.5° correspond to the (111) and (220) crystal planes respectively. The TiO2 phase may be an oxide phase formed by the reaction of lattice oxygen in CeO2 with Ti elements on the surface of the titanium-iron hydrogen storage alloy during mechanical ball milling. In addition, a small diffraction peak was observed around 40° in the XRD pattern of the titanium-iron hydrogen storage alloy material in Comparative Example 1, which may be attributed to the formation of the TiFe2 secondary phase.

[0127] (4) X-ray photoelectron spectroscopy (XPS) test

[0128] To further prove that the surface of the composite hydrogen storage material is completely coated with CeO2, the composition analysis of different depths of the surface of the composite hydrogen storage material in Example 1 and the surface of the titanium-iron hydrogen storage alloy material in Comparative Example 1 was carried out by X-ray photoelectron spectroscopy (XPS) and etching technology; Figure 4 This is the X-ray photoelectron spectroscopy diagram of the titanium-iron hydrogen storage alloy material in Comparative Example 1 of the present invention. Figure 5 This is the X-ray photoelectron spectroscopy diagram of the composite hydrogen storage material in Example 1 of the present invention.

[0129] From Figure 4 and 5 it can be concluded that after coating with CeO2, almost no Fe element can be detected on the surface of the titanium-iron (TiFe) hydrogen storage alloy, but the oxygen (O) element and cerium (Ce) element are very obvious. However, with the increase of the etching time, it can be clearly seen that the iron (Fe) element gradually appears and the content is increasing. This shows that CeO2 is completely coated on the surface of the titanium-iron (TiFe) hydrogen storage alloy.

[0130] (5) Hydrogen absorption kinetic performance test

[0131] The pure hydrogen (pure H2) and impurity gases (by volume fraction) used in the present invention are provided by China Petroleum & Chemical Corporation: ① 99.999% H2 (pure hydrogen), ② 5% CH4 + 95% H2 (CH4 + H2), ③ 0.05% CO + 0.05% CO2 + 99.9% H2 (COx + H2), ④ 0.1% O2 + 2% N2 + 97.9% H2 (O2 + H2).

[0132] Experimental method: Weigh 1 g of the sample to be tested and place it in the sample chamber of a Sieverts-type hydrogen storage tester. Evacuate the sample chamber at 25 °C for 30 min until it reaches 1×10 -4 MPa, then fill the sample chamber with different gases (pure hydrogen, CH4 + H2, COx + H2, O2 + H2) at a filling pressure of 5 MPa while maintaining the temperature at 25 °C. Open the sample valve and use a computer to record the hydrogen pressure value in the sample chamber in real time. Repeat the cycle 5 - 10 times to obtain the hydrogen absorption kinetic curve of the sample to be tested.

[0133] The composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 and the titanium iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 are respectively used as the samples to be tested and placed in the sample chamber of a Sieverts-type hydrogen storage tester for testing according to the above experimental method. Figure 6 This is the hydrogen absorption kinetic curve obtained after 10 cycles of hydrogen absorption and desorption of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 and the titanium iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 in pure hydrogen. Among them, Figure 6 (a) is the hydrogen absorption kinetic curve obtained after 10 cycles of hydrogen absorption and desorption of the titanium iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 in pure hydrogen, Figure 6 (b) is the hydrogen absorption kinetic curve obtained after 10 cycles of hydrogen absorption and desorption of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 in pure hydrogen.

[0134] Figure 7 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 and the titanium iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 in pure hydrogen and the hydrogen absorption kinetic curve obtained after 10 cycles of hydrogen absorption and desorption in CH4 + H2 (methane). Among them, Figure 7 (a) is the hydrogen absorption kinetic curve obtained after 10 cycles of hydrogen absorption and desorption of the titanium iron hydrogen storage alloy material (TiFe 0.9 ) in Comparative Example 1 in CH4 + H2 (methane), Figure 7(b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 after 10 cycles of hydrogen absorption and desorption in CH4 + H2 (methane).

[0135] Figure 8 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and the hydrogen absorption kinetic curve obtained after 10 cycles of hydrogen absorption and desorption in COx + H2 (COx). Among them, Figure 8 (a) is the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in Example 1 of the present invention after 10 cycles of hydrogen absorption and desorption in COx + H2 (COx), Figure 8 (b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 after 10 cycles of hydrogen absorption and desorption in COx + H2 (COx).

[0136] Figure 9 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and the hydrogen absorption kinetic curve obtained after 5 cycles of hydrogen absorption and desorption in O2 + H2 (oxygen). Among them, Figure 9 (a) is the hydrogen absorption kinetic curve of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) after 5 cycles of hydrogen absorption and desorption in O2 + H2 (oxygen), Figure 9 (b) is the hydrogen absorption kinetic curve of the composite hydrogen storage material (TiFe 0.9 -CeO2) after 5 cycles of hydrogen absorption and desorption in O2 + H2 (oxygen).

[0137] Figure 10 This is the comparison diagram of the hydrogen absorption kinetic performance of the composite hydrogen storage material (TiFe 0.9 -CeO2) in Example 1 of the present invention and the hydrogen absorption kinetic performance of the titanium-iron hydrogen storage alloy material (TiFe 0.9 ) in pure hydrogen and the hydrogen absorption kinetic performance obtained after 10 cycles of hydrogen absorption and desorption in different impurity gases.

[0138] From Figure 6 (a), it can be seen that the hydrogen storage capacity of the titanium-iron hydrogen storage alloy material in Comparative Example 1 decreased by 3% after 10 cycles of hydrogen absorption and desorption in pure hydrogen. From Figure 6As can be seen from (b), the hydrogen storage capacity of the composite hydrogen storage material in Example 1 decreased by only 1% after 10 cycles of hydrogen absorption and desorption in pure hydrogen. This is because as the hydrogen absorption and desorption cycles proceed, hydrogen atoms accumulated at the crack tips of the titanium-iron hydrogen storage alloy material reduce the fracture energy, weaken the metallic bonds within the titanium-iron hydrogen storage alloy material, enhance the decoupling adhesion at its crack tips, and the newly generated surfaces during fracture ensure sufficient hydrogen absorption, thus maintaining the cycling stability of the titanium-iron hydrogen storage alloy material. Compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the cycling stability and hydrogen absorption kinetics performance of the composite hydrogen storage material in Example 1 are improved.

[0139] From Figure 7 As can be seen from (a), the initial hydrogen storage capacity of the titanium-iron hydrogen storage alloy material in Comparative Example 1 was 1.476 wt%, and after 10 cycles of hydrogen absorption and desorption in CH4 + H2 (methane), the hydrogen storage capacity was 1.446 wt%. Comparing the first cycle and the tenth cycle, it can be clearly seen that the impurity gas (methane CH4) has little effect on the cycling performance of the titanium-iron hydrogen storage alloy material, and its hydrogen absorption capacity remains almost unchanged compared with pure hydrogen. However, it has a greater impact on the hydrogen absorption kinetics performance of the titanium-iron hydrogen storage alloy material. The titanium-iron hydrogen storage alloy material starts to absorb hydrogen slowly after storing hydrogen to a certain capacity until it is saturated. From Figure 7 As can be seen from (a)-(b), compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the hydrogen absorption kinetics performance of the composite hydrogen storage material in Example 1 is greatly improved, and after 10 cycles of hydrogen absorption and desorption, the hydrogen storage capacity of the composite hydrogen storage material only decays by 3%, which is better than that of the titanium-iron hydrogen storage alloy material in Comparative Example 1.

[0140] From Figure 8 As can be seen from (a), the hydrogen storage capacity of the titanium-iron hydrogen storage alloy material in Comparative Example 1 after the first cycle of hydrogen absorption and desorption was 1.401 wt%, and after the tenth cycle of hydrogen absorption and desorption in COx + H2 (COx), the hydrogen storage capacity was 1.312 wt%. Although in COx + H2 (COx), the cycling performance of the titanium-iron hydrogen storage alloy material in Comparative Example 1 decreased slightly, the decrease was relatively mild. From Figure 8 As can be seen from (a)-(b), compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the hydrogen absorption kinetics performance of the composite hydrogen storage material in Example 1 was improved to a certain extent, and the hydrogen storage capacity only decayed by 6% after 10 cycles.

[0141] From Figure 9 As can be seen from (a), in O2 + H2 (oxygen), the hydrogen storage capacity of the titanium-iron hydrogen storage alloy material in Comparative Example 1 had a 10% hydrogen loss after the second cycle of hydrogen absorption and desorption, but as the hydrogen absorption and desorption cycles continued, the hydrogen storage capacity decreased rapidly. After 5 cycles, the hydrogen storage capacity decreased by 83%. After 6 cycles of hydrogen absorption and desorption, the titanium-iron hydrogen storage alloy material lost its hydrogen absorption kinetics performance and was completely poisoned. FromFigure 9 As can be seen from (a)-(b), compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the hydrogen absorption kinetic performance of the composite hydrogen storage material in Example 1 remains almost unchanged. However, with the increase in the number of hydrogen absorption and desorption cycles, its hydrogen absorption kinetic performance accelerates. After 5 cycles, the hydrogen storage capacity decreases by 33%.

[0142] From Figures 6 - 10 it can be concluded that compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the hydrogen absorption kinetic performance and capacity retention rate of the composite hydrogen storage material in Example 1 have been greatly improved. This may be because constructing a catalytically active rare earth oxide protective layer (cerium oxide) on the surface of the titanium-iron hydrogen storage alloy can effectively block the chemisorption of impurity gases such as methane (CH4), oxygen (O2), carbon monoxide (CO), and carbon dioxide (CO2), and at the same time promote the dissociation-adsorption process of hydrogen molecules.

[0143] The composite hydrogen storage materials in Examples 2-5 were respectively placed as test samples in the sample chamber of a Sieverts-type hydrogen storage tester and tested according to the above experimental method; Figure 11 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 2 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after 5 cycles of hydrogen absorption and desorption in O2+H2 (oxygen).

[0144] Figure 12 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 3 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after 5 cycles of hydrogen absorption and desorption in O2+H2 (oxygen).

[0145] Figure 13 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 4 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after 5 cycles of hydrogen absorption and desorption in O2+H2 (oxygen).

[0146] Figure 14 This is the hydrogen absorption kinetic curve of the composite hydrogen storage material in Example 5 of the present invention in pure hydrogen and the hydrogen absorption kinetic curve obtained after 5 cycles of hydrogen absorption and desorption in O2+H2 (oxygen).

[0147] Figure 15 This is the hydrogen storage capacity of the composite hydrogen storage materials in Examples 1-5 of the present invention and the titanium-iron hydrogen storage alloy material in Comparative Example 1 in pure hydrogen, the hydrogen storage capacity after 5 cycles of hydrogen absorption and desorption in O2+H2 (oxygen), and the capacity attenuation rate after 5 cycles of hydrogen absorption and desorption in O2+H2 (oxygen).

[0148] From Figure 9 and Figure 15It can be seen that the hydrogen storage capacity of the composite hydrogen storage material in Example 1 in pure hydrogen is 1.21 wt%, and after undergoing 5 cycles of hydrogen absorption and desorption in O2 + H2, its hydrogen storage capacity decreases to 0.81 wt%, and the hydrogen storage capacity decays by 33%. The hydrogen storage capacity of the titanium-iron hydrogen storage alloy material in Comparative Example 1 in pure hydrogen is 1.46 wt%, and after undergoing 5 cycles of hydrogen absorption and desorption in O2 + H2, its hydrogen storage capacity decreases to 0.25 wt%, and the hydrogen storage capacity decays by 83%. Compared with the titanium-iron hydrogen storage alloy material in Comparative Example 1, the anti-poisoning performance of the composite hydrogen storage material in Example 1 is significantly improved. Although the hydrogen storage capacity of the composite hydrogen storage material in Example 2 is increased in pure hydrogen, after undergoing 5 cycles of hydrogen absorption and desorption in O2 + H2, the hydrogen storage capacity decays by 47%. The hydrogen storage capacity of the composite hydrogen storage material in Example 3 in pure hydrogen is 1.02 wt%, and after undergoing 5 cycles of hydrogen absorption and desorption in O2 + H2, the hydrogen storage capacity decays by 34%. The hydrogen storage capacity of the composite hydrogen storage material in Example 4 in pure hydrogen is 1.07 wt%, and after undergoing 5 cycles of hydrogen absorption and desorption in O2 + H2, the hydrogen storage capacity decays by 36%. Although the hydrogen storage capacity of the composite hydrogen storage material in Example 5 only decays by 17% after undergoing 5 cycles of hydrogen absorption and desorption in O2 + H2, due to excessive cerium oxide coating, which hinders the entry of hydrogen, its hydrogen storage capacity in pure hydrogen is less than 1 wt%, and the initial hydrogen absorption kinetic performance is poor. The above results illustrate that the composite hydrogen storage material provided in Example 1 of the present invention has both excellent anti-poisoning performance and hydrogen absorption kinetic performance.

[0149] In summary, the composite hydrogen storage material provided in the embodiments of the present invention has excellent anti-poisoning performance and hydrogen absorption kinetic performance, can resist poisoning by various impurity gases (CH4, O2, CO, CO2), reduce the poisoning effect of impurity gases in hydrogen on it, and after multiple cycles of hydrogen absorption and desorption of hydrogen containing impurity gases, the decay amount of the hydrogen storage capacity of the composite hydrogen storage material is significantly reduced.

[0150] Each embodiment in this specification is described in a related manner. For the same and similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. The above are only the preferred embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A composite hydrogen storage material with high anti-poisoning performance, characterized in that, The composite hydrogen storage material includes a titanium-iron hydrogen storage alloy and a cerium oxide, and the cerium oxide completely coats the surface of the titanium-iron hydrogen storage alloy.

2. The composite hydrogen storage material with high anti-poisoning performance according to claim 1, characterized in that, The cerium oxide includes cerium oxide.

3. The composite hydrogen storage material with high anti-poisoning performance according to claim 2, characterized in that, In the composite hydrogen storage material, the mass ratio of the titanium-iron hydrogen storage alloy to the cerium oxide is 1:(0.05 - 0.5).

4. A method for preparing a composite hydrogen storage material with high anti-poisoning performance according to any one of claims 1-3, characterized in that, It includes the following steps: Prepare a titanium-iron hydrogen storage alloy; Perform vacuum activation treatment on the titanium-iron hydrogen storage alloy to obtain the titanium-iron hydrogen storage alloy after vacuum activation treatment; Mix the titanium-iron hydrogen storage alloy after vacuum activation treatment with a cerium oxide to obtain a mixed material; Perform mechanical ball milling treatment on the mixed material to obtain the composite hydrogen storage material.

5. The preparation method of the composite hydrogen storage material with high anti-poisoning performance according to claim 4, characterized in that, Performing mechanical ball milling treatment on the mixed material includes: Put the mixed material into a ball milling tank and put in ball milling beads. At room temperature, install the ball milling tank on a ball mill, set the ball milling speed to 300 - 500 r / min, and use a ball milling process with a ball milling time of 10 min and a rest time of 10 min for mechanical ball milling treatment. The total ball milling time is 10 - 30 min.

6. The preparation method of the composite hydrogen storage material with high anti-poisoning performance according to claim 5, characterized in that, The mass ratio of the mixed material to the ball milling beads is 1:(40 - 80).

7. The preparation method of the composite hydrogen storage material with high anti-poisoning performance according to claim 5, characterized in that, The diameter of the ball milling beads is at least one of 3 mm, 6 mm, and 8 mm.

8. The preparation method of the composite hydrogen storage material with high anti-poisoning performance according to claim 4, characterized in that Mixing the titanium-iron hydrogen storage alloy after vacuum activation treatment with a cerium oxide to obtain a mixed material includes: Mix the titanium-iron hydrogen storage alloy after vacuum activation treatment with a cerium oxide evenly under the conditions of pure argon with a purity greater than 99.99% and the concentrations of water vapor and oxygen lower than 0.01 ppm to obtain a mixed material.

9. The preparation method of the composite hydrogen storage material with high anti-poisoning performance according to claim 4, characterized in that, The preparation of the titanium-iron hydrogen storage alloy includes: Under the protection of an argon atmosphere, perform vacuum arc melting on a mixture of titanium and iron elements, and obtain the titanium-iron hydrogen storage alloy after cooling.

10. The preparation method of the composite hydrogen storage material with high anti-poisoning performance according to claim 9, characterized in that, The molar ratio of the titanium element to the iron element is 1.1:0.9.

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