A preparation method of a La-containing high-entropy alloy and a magnesium hydride hydrogen storage material thereof

Abstract

The application discloses a La-containing high-entropy alloy and a preparation method thereof. The La-containing high-entropy alloy is prepared by smelting Ti, Mn, Fe, Co, Ni and La in a mass ratio of 1:1:1:1:1:0.1, and the mass of La is additionally increased by 3wt% of the burning loss mass; the La-containing high-entropy alloy contains CoFe phase, NiTi phase and FeNi phase; and the particle size is 100-200 meshes. A preparation method of a magnesium hydride hydrogen storage material based on the La-containing high-entropy alloy is to perform ball milling on HEA-La and MgH2. The obtained magnesium hydride hydrogen storage material based on the La-containing high-entropy alloy is applied to the hydrogen storage field. When the catalyst doping amount is 10wt%, the initial hydrogen release temperature is reduced to 179.44-180.33 DEG C, and the hydrogen release amount reaches 6.46-6.45wt%; under the conditions that the dehydrogenation temperature is 300 DEG C, the dehydrogenation time is 30 min, the hydrogen release amount is 6.17-6.78wt%; under the conditions that the hydrogen pressure is 3Mpa, the hydrogen absorption temperature is 170 DEG C, and the hydrogen absorption time is 5 min, the hydrogen absorption amount is 5.23-5.24wt%.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage materials technology, and in particular to a method for preparing a La-containing high-entropy alloy and its magnesium hydride hydrogen storage material. Background Technology

[0002] Magnesium hydride (MgH2) has a high hydrogen storage density of 7.6 wt%, and possesses excellent reversibility, non-toxicity, and low cost. However, it suffers from high hydrogen release temperature and slow kinetic performance. Currently, a common technical solution for improving MgH2 is to use doped alloys as catalysts. Common alloy catalyst systems include TiFe alloy system, TiMn alloy system, and LaNi alloy system. Among them, in the LaNi alloy system, LaH5 reacts with MgH2 in situ to form Mg2Ni phase and LaH3 phase, which can effectively promote the dissociation of hydrogen molecules. For example, existing literature 1 (Liu Yu, Zhang Jian, Pang Xiaotong, et al. Influence and mechanism of lanthanum-nickel alloy on the microstructure and hydrogen storage performance of magnesium hydride [J]. Materials Reports, 2025, 39(08): 138-143.) obtained LaH3 alloy through vacuum melting, which can reduce the initial hydrogen release temperature of MgH2 to 247℃ and release 6.0 wt% hydrogen gas within 300℃ and 500s. However, the initial hydrogen decomposition temperature of the LaNi alloy catalyst obtained by this technical solution is still higher than 247℃, and the activation energy is greater than 80kJ / mol, indicating poor thermodynamic performance in hydrogen decomposition. This is because the metal element composition of this type of alloy catalyst is usually two-element, thus exhibiting a low entropy value (≤1.5R), i.e., a low-entropy alloy. The atomic arrangement and electronic structure on the surface of low-entropy alloys tend to be more ordered, leading to a reduction in active sites and ultimately resulting in poor catalytic performance.

[0003] To address the aforementioned issues, high-entropy alloys can be prepared by adding components, thereby further improving the hydrogen storage kinetics of MgH2. The principle behind the improved hydrogen storage kinetics of high-entropy alloys (HEAs) is based on the fundamental characteristics of high-entropy alloys, specifically the electronic structure and lattice distortion among multi-metallic elements resulting from the combination of five or more metallic elements. For example, existing literature 2 (Wan H, Yang X, Zhou S, et al. "Enhancing hydrogen storage properties of MgH2 using FeCoNiCrMn high entropy alloy catalysts" [J]. Journal of Materials Science & Technology, 2023, 149: 88-98.) uses the same vacuum melting method as existing literature 1 to obtain the alloy, followed by mechanical crushing to obtain FeCoNiCrMn high-entropy alloy powder. This reduces the initial hydrogen release temperature of MgH2 to 209℃, and allows the release of 5.8 wt% hydrogen within 240 seconds at 300℃. However, research and analysis show that the direct reason for the poor performance of this technical solution is that the resulting alloy is a face-centered cubic FCC solid solution phase, which directly leads to a small lattice distortion of only 3.74%. The essential reason is that the five metal elements used in this technical solution are adjacent elements, that is, the atomic radii are small.

[0004] Therefore, to improve the degree of lattice distortion, high-entropy alloys with significantly different atomic radii can be prepared. For example, existing literature 3 (Song MC, Wu FY, Jiang YQ, et al. "Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de / hydrogenation performance of magnesium hydride" [J]. Rare Metals, 2024, 43(7): 3273-3285.) prepared FeCoNiCrTi high-entropy alloy powder, which can reduce the initial hydrogen release temperature of MgH2 to 198℃, and release 6.62wt% of hydrogen gas within 290℃ and 600s. The lattice distortion of FeCoNiCrTi obtained by this technical solution is 6.62%, which is higher than that of the aforementioned comparative literature 2, and a corresponding improvement in technical performance is achieved.

[0005] Analysis of existing literature 2 and 3 shows that the degree of lattice distortion is also one of the criteria affecting catalytic performance. However, the catalytic performance of existing literature 3 still cannot meet the application requirements. The reason is that the Cr element in the high-entropy alloy oxidizes during the preparation process to form a Cr2O3 passivation layer, which hinders hydrogen diffusion and ultimately leads to the catalytic performance failing to meet expectations. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing a La-containing high-entropy alloy and its magnesium hydride hydrogen storage material.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following inventive concept: In order to obtain a high-entropy alloy with a higher degree of lattice distortion, TiMnFeCoNi is selected as the high-entropy alloy. By adding a trace amount of La metal, the degree of lattice distortion of HEA is increased from 6.22% to 15.88%, which greatly improves the degree of lattice distortion of HEA. At the same time, it achieves the effect of destroying the density and stability of the surface oxide layer, effectively reducing the initial hydrogen desorption performance of magnesium hydride.

[0008] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0009] A high-entropy alloy containing La is smelted with the molar ratio of Ti, Mn, Fe, Co, Ni and La being 1:1:1:1:1:0.1, and the mass of La is additionally increased by 3 wt% of the mass lost during burning.

[0010] The HEA-La high-entropy alloy simultaneously contains CoFe phase, NiTi phase, and FeNi phase;

[0011] The HEA-La high-entropy alloy has a particle size of 100-200 mesh.

[0012] A method for preparing a La-containing high-entropy alloy involves using Ti, Mn, Fe, Co, Ni, and La in a molar ratio of 1:1:1:1:1:0.1, with an additional 3 wt% loss of La due to burn-off. The alloy is then subjected to arc melting under specific conditions to obtain the La-containing high-entropy alloy, abbreviated as HEA-La. The method is carried out under a vacuum of 2 × 10⁻⁶. -3 The protective gas is argon gas at a pressure of 0.05 MPa, and the number of inversions is 5.

[0013] A method for preparing magnesium hydride hydrogen storage material based on a La-containing high-entropy alloy includes the following steps: ball milling HEA-La and MgH2 under certain conditions to obtain magnesium hydride hydrogen storage material based on a La-containing high-entropy alloy, referred to as MgH2-HEA-La;

[0014] The ball milling conditions are: a mass ratio of 10:90, a ball-to-material ratio of 80:1, a ball milling speed of 400 rpm, a ball milling time of 12 h, and a certain ball milling interval.

[0015] The conditions for ball milling also include the existence of a ball milling interval, wherein the ball milling is paused after each ball milling time of 12 minutes for a pause time of 6 minutes.

[0016] The resulting magnesium hydride hydrogen storage material based on La-containing high-entropy alloy, when applied in the field of hydrogen storage, shows that when the catalyst doping amount is 10 wt%, the initial hydrogen release temperature drops to 179.44-180.33℃, and the hydrogen release amount reaches 6.46-6.45 wt%.

[0017] Under the conditions of dehydrogenation temperature of 300℃ and dehydrogenation time of 30min, the hydrogen release is 6.17-6.78wt%; under the conditions of hydrogen pressure of 3MPa, hydrogen absorption temperature of 170℃ and hydrogen absorption time of 5min, the hydrogen absorption is 5.23-5.24wt%.

[0018] The technical effects of this invention have been tested experimentally, and the specific details are as follows:

[0019] EDS test results show that HEA-La contains Ti, Mn, Fe, Co, and Ni elements, as well as La. Furthermore, the atomic contents of Ti, Mn, Fe, Co, and Ni are similar, all close to 20 at.%. The test results indicate that HEA-La is a high-entropy alloy.

[0020] XRD test results show that HEA-La simultaneously contains characteristic peaks of CoFe phase, NiTi phase, and FeNi phase.

[0021] Thermodynamic tests on dehydrogenation showed that the initial hydrogen release temperature was 179.44-180.33℃, and the hydrogen release amount was 5.50-5.57 wt% at a test temperature of 300℃, reaching 83.63-82.58% of the theoretical maximum hydrogen release amount of 6.66 wt%; the total hydrogen release amount reached 6.46-6.45 wt%, reaching 96.84-97.00% of the theoretical maximum hydrogen release amount.

[0022] The dehydrogenation kinetics test results show that, under the conditions of a dehydrogenation temperature of 300℃ and a dehydrogenation time of 30 min, the hydrogen release is 6.17-6.78 wt%.

[0023] The dehydrogenation kinetics test results show that under the conditions of hydrogen pressure of 3 MPa, hydrogen absorption temperature of 170℃, and hydrogen absorption time of 5 min, the hydrogen absorption amount is 5.23-5.24 wt%.

[0024] Therefore, the present invention has the following advantages over the prior art:

[0025] 1. This invention greatly increases the lattice distortion of HEA by incorporating trace amounts of La metal, generating a large number of dislocations and defects. This effectively disrupts the compactness and stability of its surface oxide layer, increases the active sites in the hydrogen storage reaction process, reduces the initial hydrogen release temperature of MgH2, and achieves rapid hydrogen absorption and desorption, thereby improving the hydrogen storage performance of MgH2.

[0026] 2. The method used to prepare the La-containing high-entropy alloy according to the present invention only requires trace amounts of La metal, and has the advantages of low cost, simple preparation process, controllable reaction and easy large-scale preparation. Attached Figure Description

[0027] Figure 1 The EDS spectrum of HEA-La prepared in Example 1;

[0028] Figure 2 The XRD pattern of HEA-La prepared in Example 1;

[0029] Figure 3 The temperature-induced dehydrogenation curves for Examples 1 and 2, and Comparative Examples 1, 2, 3, and 4 are shown.

[0030] Figure 4 The isothermal dehydrogenation curve of MgH2-HEA-La-10 prepared in Example 1 is shown.

[0031] Figure 5 The isothermal dehydrogenation curve of BM-MgH2 prepared in Comparative Example 1 is shown.

[0032] Figure 6 The isothermal hydrogen absorption curve of MgH2-HEA-La-10 prepared in Example 1 is shown.

[0033] Figure 7 The image shows the isothermal hydrogen absorption curve of BM-MgH2 prepared in Comparative Example 1. Detailed Implementation

[0034] The present invention will be further described in detail through embodiments and with reference to the accompanying drawings, but this is not intended to limit the scope of the invention.

[0035] Example 1

[0036] A method for preparing a La-containing high-entropy alloy includes the following steps: The molar ratio of Ti, Mn, Fe, Co, Ni, and La is 1:1:1:1:1:0.1, with an additional 3wt% loss of La due to burn-off. First, using ethanol as the cleaning solution, 3.292g of Ti metal, 3.776g of Mn metal, 3.840g of Fe metal, 4.054g of Co metal, 4.036g of Ni metal, and 1.000g of La metal are ultrasonically cleaned for 30 minutes. Then, the alloy is subjected to a vacuum of 2×10⁻⁶. -3 Arc melting was carried out under the conditions of using argon gas at a pressure of 0.05 MPa as the protective gas and performing 5 inversions.

[0037] The conditions for arc melting are as follows: first, La is melted under a current intensity of 100A. After the La metal is completely melted, Ni metal, Co metal, Fe metal, Mn metal and Ti metal are added sequentially under a current intensity of 200A and melted until completely melted. After melting, the resulting alloy is cooled in the furnace to obtain an alloy ingot. The obtained alloy ingot is then ground, crushed, pulverized and sieved to obtain a La-containing high-entropy alloy, abbreviated as HEA-La.

[0038] The particle size sieved is 200 mesh.

[0039] To verify that the composition of HEA-La meets the requirements of a high-entropy alloy, EDS testing was performed. The test results are as follows: Figure 1 As shown in Table 1, HEA-La contains Ti, Mn, Fe, Co, and Ni elements, as well as La. Furthermore, the atomic contents of Ti, Mn, Fe, Co, and Ni are similar, all approaching 20 at.%. Test results indicate that HEA-La is a high-entropy alloy.

[0040] Table 1. Elemental composition of HEA-La high-entropy alloy

[0041] Ti 16.41 19.52 Mn 19.21 19.93 Fe 18.58 18.95 Co 19.96 19.30 Ni 20.88 20.26 La 4.96 2.03 Total: 100.00 100.00

[0042] To verify the crystal structure of HEA-La, XRD tests were performed. The test results are as follows: Figure 2 As shown, HEA-La simultaneously contains characteristic peaks of CoFe phase, NiTi phase, and FeNi phase.

[0043] A magnesium hydride hydrogen storage material based on a La-containing high-entropy alloy includes the following steps: ball milling is performed with a mass ratio of HEA-La to MgH2 of 10:90, a ball-to-material ratio of 80:1, a ball milling speed of 400 rpm, a ball milling time of 12 h, and a certain ball milling interval, to obtain the magnesium hydride hydrogen storage material based on the La-containing high-entropy alloy, abbreviated as MgH2-HEA-La. In specific embodiment 1, the MgH2-HEA-La obtained is named MgH2-HEA-La-10 because the content of HEA-La is 10 wt.%.

[0044] The ball milling interval is defined as follows: after each ball milling session of 12 minutes, the ball milling is paused for 6 minutes.

[0045] To demonstrate the thermodynamic performance of HEA-La as a catalyst for dehydrogenation, a temperature-intensity dehydrogenation test was conducted on MgH2-HEA-La-10. The results of the temperature-intensity dehydrogenation test are as follows: Figure 3 As shown, the initial hydrogen release temperature was 179.44℃, which was 101.6℃ lower than that of pure magnesium hydride. At a test temperature of 300℃, the hydrogen release was 5.57wt%, reaching 83.63% of the theoretical maximum hydrogen release of 6.66wt%, i.e., the hydrogen release rate reached 83.63%. The total hydrogen release reached 6.46wt%, reaching 97.00% of the theoretical maximum hydrogen release.

[0046] To demonstrate the hydrogen absorption and desorption kinetics performance of HEA-La as a catalyst, isothermal dehydrogenation and isothermal hydrogen absorption tests were performed on MgH2-HEA-La-10.

[0047] Isothermal dehydrogenation test results are as follows Figure 4 As shown, under the conditions of a dehydrogenation temperature of 300℃ and a dehydrogenation time of 30 min, the hydrogen release is 6.18 wt%.

[0048] Isothermal hydrogen absorption test results are as follows Figure 5 As shown, under the conditions of hydrogen pressure of 3 MPa, hydrogen absorption temperature of 170℃, and hydrogen absorption time of 5 min, the hydrogen absorption amount is 5.23 wt%.

[0049] To demonstrate the effect of HEA-La as a catalyst on the performance of magnesium hydride, Comparative Example 1 is provided, showing magnesium hydride hydrogen storage material prepared without HEA-La doping.

[0050] Comparative Example 1.

[0051] A method for preparing magnesium hydride hydrogen storage material without HEA-La doping. The steps not specifically described are the same as in Example 1, except that HEA-La is not added. The resulting magnesium hydride hydrogen storage material is referred to as BM-MgH2.

[0052] The results of the temperature-induced dehydrogenation test of BM-MgH2 are as follows: Figure 3 As shown, the initial hydrogen release temperature was 281.04℃; at a test temperature of 300℃, the hydrogen release was only 0.19wt%, reaching only 2.53% of the theoretical maximum hydrogen release of 7.5wt%, i.e., the hydrogen release rate was 2.53%. Compared with Example 1, it can be seen that introducing HEA-La as a catalyst can significantly reduce the initial hydrogen release temperature from 281.04℃ to 179.44℃, a reduction of 101.6℃; and significantly increase the hydrogen release rate from 2.53% to 86.63%. The test results show that doping with HEA-La as a catalyst can significantly improve the thermodynamic performance of magnesium hydride in hydrogen release.

[0053] The isothermal dehydrogenation test results of BM-MgH2 are as follows: Figure 6 As shown, under the conditions of a dehydrogenation temperature of 300℃ and a dehydrogenation time of 30 min, the hydrogen release was 0.35 wt%. Compared with Example 1, it can be seen that the introduction of HEA-La as a catalyst can significantly increase the hydrogen release from 0.35 wt% to 6.18 wt%, an increase of 1765.7%. The test results show that doping with HEA-La as a catalyst can improve the dehydrogenation kinetics of magnesium hydride.

[0054] The isothermal hydrogen absorption test results of BM-MgH2 are as follows: Figure 7 As shown, under the conditions of a hydrogen pressure of 3 MPa, a hydrogen absorption temperature of 170°C, and a hydrogen absorption time of 5 min, the hydrogen absorption capacity was 1.34 wt%. Compared with Example 1, it can be seen that introducing HEA-La as a catalyst can significantly increase the hydrogen absorption capacity from 1.34 wt% to 5.23 wt% at a hydrogen absorption temperature of 170°C, an increase of 389.3%. The test results of introducing HEA-La as a catalyst show that doping with HEA-La can improve the hydrogen absorption kinetics of magnesium hydride.

[0055] To further demonstrate the effect of HEA-La doping on the performance of magnesium hydride, comparative examples 2, 3, 4, and 5 are provided, with HEA-La doping amounts of 3 wt%, 5 wt%, 7 wt%, and 12 wt%, respectively, of magnesium hydride hydrogen storage materials.

[0056] Comparative Example 2

[0057] A method for preparing a magnesium hydride hydrogen storage material with a HEA-La doping amount of 3 wt% is described. The steps not specifically described are the same as those in Example 1, except that the HEA-La doping amount is 3 wt%. The resulting magnesium hydride hydrogen storage material is referred to as MgH2-HEA-La-3.

[0058] The results of the temperature-induced dehydrogenation test of MgH2-HEA-La-3 are as follows: Figure 3As shown, the initial hydrogen release temperature was 197.88℃; at a test temperature of 300℃, the hydrogen release was only 1.49wt%, reaching only 20.49% of the theoretical maximum hydrogen release of 7.27wt%, i.e., the hydrogen release rate was 20.49%. Compared with Example 1, it can be seen that increasing the content of HEA-La as a catalyst can significantly reduce the initial hydrogen release temperature from 197.88℃ to 179.44℃, a reduction of 18.44℃; and significantly increase the hydrogen release rate from 20.49% to 83.63%. The test results show that increasing the content of HEA-La can reduce the initial hydrogen release temperature and increase the hydrogen release rate.

[0059] Comparative Example 3

[0060] A method for preparing magnesium hydride hydrogen storage material doped with 5wt% HEA-La is described. The steps not specifically described are the same as in Example 1, except that 5wt% HEA-La is added and ball milled to obtain magnesium hydride hydrogen storage material doped with 5wt% HEA-La, which is abbreviated as MgH2-HEA-La-5.

[0061] The results of the temperature-induced dehydrogenation test of MgH2-HEA-La-5 are as follows: Figure 3 As shown, the initial hydrogen release temperature was 195.87℃; at a test temperature of 300℃, the hydrogen release was only 2.84wt%, reaching 39.86% of the theoretical maximum hydrogen release of 7.12wt%, i.e., the hydrogen release rate was 39.86%. Compared with Example 1, it can be seen that increasing the content of HEA-La as a catalyst can reduce the initial hydrogen release temperature from 195.87℃ to 179.44℃, a reduction of 16.43℃; and significantly increase the hydrogen release rate from 39.86% to 86.63%. The test results are the same as those of Comparative Example 2, that is, increasing the content of HEA-La can reduce the initial hydrogen release temperature and increase the hydrogen release rate.

[0062] Comparative Example 4

[0063] A method for preparing magnesium hydride hydrogen storage material doped with 7wt% HEA-La is described. The steps not specifically described are the same as in Example 1, except that 7wt% HEA-La is added and ball milled to obtain magnesium hydride hydrogen storage material doped with 7wt% HEA-La, which is abbreviated as MgH2-HEA-La-7.

[0064] The results of the temperature-induced dehydrogenation test of MgH2-HEA-La-7 are as follows: Figure 3As shown, the initial hydrogen release temperature was 209.04℃; at a test temperature of 300℃, the hydrogen release was 4.35 wt%, reaching 62.37% of the theoretical maximum hydrogen release of 6.98 wt%, i.e., the hydrogen release rate was 62.37%. Compared with Example 1, it can be seen that increasing the content of HEA-La as a catalyst can significantly reduce the initial hydrogen release temperature from 209.04℃ to 179.44℃, a reduction of 85.9%; and significantly increase the hydrogen release rate from 62.37% to 86.63%. The test results are the same as those of Comparative Example 2, that is, increasing the content of HEA-La can reduce the initial hydrogen release temperature and increase the hydrogen release rate.

[0065] Example 2

[0066] A method for preparing magnesium hydride hydrogen storage material doped with 12% HEA-La is described. The steps not specifically described are the same as in Example 1, except that 12% HEA-La is added and ball milled to obtain magnesium hydride hydrogen storage material doped with 12% HEA-La, which is abbreviated as MgH2-HEA-La-12.

[0067] The results of the temperature-induced dehydrogenation test of MgH2-HEA-La-12 are as follows: Figure 3 As shown, the initial hydrogen release temperature was 188.72℃; at a test temperature of 300℃, the hydrogen release amount was 5.30 wt%, reaching 80.30% of the theoretical maximum hydrogen release amount of 6.60 wt%, i.e., the hydrogen release rate was 80.30%. Compared with Example 1, it can be seen that introducing 10 wt% HEA-La as a catalyst can reduce the initial hydrogen release temperature from 188.72℃ to 179.44℃, a reduction of 70.1%; and increase the hydrogen release rate from 80.30% to 86.63%. The test results show that although an excessive amount of HEA-La can further increase the hydrogen release rate, it actually leads to a decrease in the initial hydrogen release temperature.

Claims

1. A high-entropy alloy containing La, characterized in that: The materials were smelted with Ti, Mn, Fe, Co, Ni and La in a molar ratio of 1:1:1:1:1:0.1, and the mass of La was increased by an additional 3 wt% of the mass lost on ignition. The HEA-La high-entropy alloy simultaneously contains CoFe phase, NiTi phase, and FeNi phase; The HEA-La high-entropy alloy has a particle size of 100-200 mesh.

2. A method for preparing a La-containing high-entropy alloy, characterized in that: With the molar ratio of Ti, Mn, Fe, Co, Ni and La being 1:1:1:1:1:0.1, and with an additional 3 wt% loss of La due to burn-off, a high-entropy alloy containing La, abbreviated as HEA-La, can be obtained by arc melting under certain conditions. The conditions for the electric arc melting are as follows: a vacuum degree of 2 × 10⁻⁶. -3 The protective gas is argon gas at a pressure of 0.05 MPa, and the inversion is performed 5 times.

3. A method for preparing magnesium hydride hydrogen storage materials based on La-containing high-entropy alloys, characterized in that... Includes the following steps: By ball milling HEA-La and MgH2 under certain conditions, a magnesium hydride hydrogen storage material based on a La-containing high-entropy alloy can be obtained, which is simply referred to as MgH2-HEA-La; The ball milling conditions are: a mass ratio of 10:90, a ball-to-material ratio of 80:1, a ball milling speed of 400 rpm, a ball milling time of 12 h, and a certain ball milling interval. The conditions for ball milling also include the existence of a ball milling interval, wherein the ball milling is paused after each ball milling time of 12 minutes for a pause time of 6 minutes.

4. The preparation method according to claim 3, characterized in that: When the obtained magnesium hydride hydrogen storage material based on La-containing high-entropy alloy is applied in the field of hydrogen storage, the initial hydrogen release temperature drops to 179.44-180.33℃ and the hydrogen release amount reaches 6.45-6.46 wt% when the catalyst doping amount is 10 wt%.

5. The preparation method according to claim 3, characterized in that: The obtained magnesium hydride hydrogen storage material based on La-containing high-entropy alloy, when applied in the field of hydrogen storage, exhibits a hydrogen release of 6.17-6.78 wt% under the conditions of a dehydrogenation temperature of 300℃ and a dehydrogenation time of 30 min; and a hydrogen absorption of 5.23-5.24 wt% under the conditions of a hydrogen pressure of 3 MPa, a hydrogen absorption temperature of 170℃, and a hydrogen absorption time of 5 min.

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