Method for improving hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4 (at) C catalyst
By preparing Ni3Fe/Ni/NiFe2O4@C catalyst and ball milling it with MgH2, the problems of high thermal stability and slow kinetic performance of MgH2 were solved, and the high efficiency hydrogen storage performance of MgH2 was improved.
Patent Information
- Application Number
- CN202510921938.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-04
- Publication Date
- 2025-10-17
AI Technical Summary
Magnesium hydride (MgH2) has limited its practical application in hydrogen storage materials due to its high thermal stability and sluggish kinetics in dehydrogenation and hydrogenation processes.
Ni3Fe/Ni/NiFe2O4@C catalyst was prepared by hydrothermal reaction and high-temperature calcination, and then ball-milled with MgH2 powder to form Ni3Fe/Ni/NiFe2O4@C catalyst, which significantly improved the hydrogen storage performance of MgH2.
It significantly reduced the dehydrogenation activation energy of MgH2, improved its kinetic performance, and enhanced its hydrogen absorption and desorption efficiency and cycle stability.
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Figure CN120793841A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of hydrogen storage materials, and particularly relates to a method for improving hydrogen storage performance of magnesium hydride based on a Ni3Fe / Ni / NiFe2O4@C catalyst. BACKGROUND
[0002] Hydrogen energy has attracted extensive attention of researchers due to its high heat value, no pollution and renewable characteristics. However, the hydrogen storage technology is still a major problem in the application of hydrogen energy. Magnesium hydride (MgH2) is considered as a solid-state hydrogen storage material with great potential due to its abundant raw material reserves, low cost, high hydrogen storage capacity (mass capacity of 7.6wt%, volume capacity of 110g / L) and good reversibility. Unfortunately, MgH2 has high thermodynamic stability (ΔH=75kJ / mol), and the kinetics of dehydrogenation and hydrogenation processes is slow, which greatly limits its practical application.
[0003] At present, researchers mainly optimize the hydrogen storage performance of MgH2 through alloying, nanocrystallization treatment, adding catalyst and other means. Among them, adding a catalyst is considered as a simple and effective method. Adding a transition metal as a catalyst can weaken the Mg-H bond, reduce the stability of MgH2, and thus improve its hydrogen storage performance. Many studies have shown that double transition metals can more significantly improve the hydrogen storage performance of MgH2. Therefore, the development of double transition metal complexes has important value for improving the hydrogen storage performance of MgH2. SUMMARY
[0004] The purpose of the present application is to provide a method for improving the hydrogen storage performance of magnesium hydride based on a Ni3Fe / Ni / NiFe2O4@C catalyst. The Ni3Fe / Ni / NiFe2O4@C catalyst is prepared by a hydrothermal reaction method and a high-temperature calcination method, which significantly improves the hydrogen storage performance of MgH2 and promotes the practical application of MgH2.
[0005] The method for improving the hydrogen storage performance of magnesium hydride based on a Ni3Fe / Ni / NiFe2O4@C catalyst according to the present application comprises the following steps:
[0006] (1) First, dissolve nickel chloride hexahydrate, iron chloride hexahydrate and terephthalic acid in N,N-dimethylformamide, and ultrasonic for 0.5h, then transfer to a stainless steel autoclave, and keep in a 150℃ muffle furnace for 24h. After washing with ethanol for 3 times, place in a 60℃ vacuum drying box overnight to obtain a Ni / Fe-MOF precursor.
[0007] (2) Put 0.5g of the Ni / Fe-MOF precursor into a tube furnace for carbonization, keep at 700-900℃ for 3h, and the temperature rising rate is 3℃ / min to obtain the catalyst.
[0008] (3) The prepared catalyst Ni3Fe / Ni / NiFe2O4@C is ball milled with MgH2 powder at a mass ratio of 9:1 in a vacuum ball mill tank with an argon atmosphere, a rotation speed of 500 rpm, and a ball powder ratio of (30-120):1. To prevent overheating, the ball mill is stopped for 10 min every 20 min of rotation. To facilitate subsequent performance testing, the obtained MgH2-Ni3Fe / Ni / NiFe2O4@C composite material is stored in an argon-filled glove box.
[0009] The present application has the following characteristics:
[0010] (1) Compared with the prior art, the raw materials used in the present application are all industrialized production raw materials, which are easy to obtain and inexpensive.
[0011] (2) The experimental process is simple, and the equipment is easy to operate.
[0012] (3) The synthesized Ni3Fe / Ni / NiFe2O4@C significantly improves the hydrogen storage performance of MgH2. Analysis shows that the Ni3Fe / Ni / NiFe2O4@C catalyst at a carbonization temperature of 800℃ has the best hydrogen absorption and desorption performance effect on MgH2. The dehydrogenation starting temperature of MgH2-10NiFe-800 composite material is 170.5℃, and the dehydrogenation peak temperature is 289.7℃, which is much lower than the desorption temperature of MgH2.
[0013] (4) With the addition of Ni3Fe / Ni / NiFe2O4@C catalyst, the hydrogen absorption and desorption kinetics of MgH2 is greatly improved. For example, MgH2-5NiFe-800 releases 0.50wt% hydrogen in 10 min at 250℃, and 3.12wt% hydrogen in 60 min. In addition, when the temperature rises to 275 and 300℃, the sample releases 3.70 and 5.95wt% hydrogen in 10 min, respectively, and 6.14 and 6.37wt% hydrogen in 60 min, respectively.
[0014] (5) When 10 and 15wt% NiFe-800 catalysts are added, 0.92 and 1.11wt% hydrogen are released in 10 min at 250℃, respectively, and 3.57 and 3.87wt% hydrogen are released in 60 min, respectively. When the temperature is 275℃, 4.08 and 4.44wt% are released in 10 min, respectively, and 5.85 and 5.67wt% are released in 60 min, respectively. In addition, when the temperature rises to 300℃, 5.66 and 5.55wt% hydrogen are released in 10 min, respectively, and 5.96 and 5.73wt% hydrogen are released in 60 min, respectively. Finally, when the temperature is 325℃, 5.79 and 5.60wt% hydrogen are released in 5 min, respectively, and 6.00 and 5.73wt% hydrogen are released in 60 min, respectively.
[0015] (6) The activation energy of MgH2-10NiFe-800 composite material is 90.72±6.98kJ / mol, which significantly reduces the dehydrogenation activation energy of MgH2. Moreover, the composite material has excellent cycle performance, and after 10 hydrogen absorption and release cycles, the dehydrogenation capacity retention rate is 100%. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 The XRD spectrum of NiFe-800 in the embodiment of the application.
[0017] Figure 2 The SEM picture of NiFe-800 in the embodiment of the application.
[0018] Figure 3 The DSC curve (a) and TPD curve (b) of MgH2 and MgH2-10NiFe-800 composite material in the embodiment of the application.
[0019] Figure 4 The isothermal dehydrogenation curve of MgH2 and MgH2-10NiFe-800 composite material at different temperatures in the embodiment of the application: (a) MgH2, (b) MgH2-10NiFe-800.
[0020] Figure 5 The Arrhenius fitting curve graph of MgH2 and MgH2-10NiFe-800 composite material in the embodiment of the application.
[0021] Figure 6 The isothermal hydrogen absorption curve of MgH2 and MgH2-10NiFe-800 composite material at different temperatures in the embodiment of the application: (a) MgH2, (b) MgH2-10NiFe-800. DETAILED DESCRIPTION
[0022] The specific embodiments of the application will be further described in detail below in combination with the embodiments and the drawings of the specification.
[0023] Embodiment:
[0024] Firstly, 0.2377 g of nickel chloride hexahydrate, 0.2703 g of iron chloride hexahydrate and 0.3323 g of terephthalic acid were dissolved in 56 mL of N,N-dimethylformamide, ultrasonic for 0.5 h, then transferred to a stainless steel autoclave and kept in a 150 ℃ muffle furnace for 24 h. After washing with ethanol for 3 times, it was placed in a vacuum drying box at 60 ℃ overnight to obtain the Ni / Fe-MOF precursor; then the Ni / Fe-MOF precursor was placed in a tube furnace for carbonization, the temperature was set to 800 ℃, to obtain the double transition metal NiFe-800; finally, the magnesium hydride and the catalyst were ball milled in different mass ratios to obtain the magnesium-based composite hydrogen storage material. The prepared NiFe-800 and MgH2 powder were ball milled in a mass ratio of 1:9 for 6 h in a vacuum ball milling tank, the argon atmosphere was maintained, the ball powder ratio was 120:1, the rotation speed was 500 rpm, and the ball mill was stopped for 10 min every 20 min of rotation. For comparison, the pure MgH2 powder was ball milled under the same conditions. In order to test the subsequent performance, the obtained MgH2 and MgH2-10NiFe-800 composite materials were stored in an argon-filled glove box.
[0025] Firstly, the synthesized double transition metal composite was characterized by XRD and SEM, from Figure 1 and Figure 2 The results show that the Ni3Fe / Ni / NiFe2O4@C catalyst with C framework and uniformly dispersed Ni particles and a small amount of NiFe2O4 large particles is successfully prepared.
[0026] In order to explore the effect of adding 10wt% NiFe-800 on the hydrogen storage performance of MgH2, the non-isothermal dehydrogenation performance and isothermal dehydrogenation performance of MgH2 and MgH2-10NiFe-800 composite materials were tested. Figure 3 (a) is the DSC curve of MgH2 and MgH2-10NiFe-800 composite materials, the heating rate is 10 ℃ / min, it can be found that the dehydrogenation peak temperature of ball milled MgH2 is 395.8 ℃, and the dehydrogenation peak temperature of MgH2-10NiFe-800 composite material is 289.7 ℃, which is reduced by 106.1 ℃ compared with ball milled MgH2. Figure 3 (b) is the TBD curve of MgH2 and MgH2-10NiFe-800 composite materials, the heating rate is 2 ℃ / min, in Figure 3 In (b), the initial dehydrogenation temperature of ball milled MgH2 is 308.3 ℃, and the initial dehydrogenation temperature of MgH2-10NiFe-800 composite material is 170.5 ℃, the addition of NiCo2S4 catalyst reduces the initial dehydrogenation temperature of MgH2 by 137.8 ℃. From Figure 4It can be seen that the MgH2-10NiFe-800 composite material can release 4.08wt.% and 5.66wt.% H2 at 275℃ and 300℃ for 10min, and the dehydrogenation is basically completed in 5min at 325℃, and the dehydrogenation amount is 5.79wt.% H2. However, at 300℃ and 325℃, MgH2 releases 0.54wt.% and 2.65wt.% H2 in 10min, respectively. It can be seen from the Arrhenius fitting curve graph ( Figure 5 ) that the activation energy of MgH2 is 129.38±3.54kJ / mol, and the activation energy of the MgH2-10NiFe-800 composite material is 90.72±6.98kJ / mol. The results show that the dehydrogenation performance of MgH2 is obviously improved by doping the NiFe-800 catalyst.
[0027] In addition, the isothermal hydrogen absorption test of MgH2 and MgH2-10NiFe-800 composite material was carried out. At 75℃ and 100℃, MgH2-10NiFe-800 composite material absorbs 2.04wt.% and 4.17wt.% H2 in 10min, respectively, and MgH2-10NiFe-800 composite material absorbs 5.75wt.% at 150℃ in 1min. However, at 150℃, MgH2 absorbs 1.55wt.% H2 in 10min. The results show that the addition of catalyst can greatly improve the hydrogen absorption kinetics performance of the composite material.
[0028] The above only describes the preferred embodiments of the present application, and does not limit the present application in any form. It should be noted that for ordinary skilled persons in the art, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.
Claims
1. A method for improving the hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4@C catalyst, characterized in that: The steps include: (1) Nickel chloride hexahydrate, ferric chloride hexahydrate, and terephthalic acid were dissolved in N,N-dimethylformamide, ultrasonicated for 0.5 h, then transferred to a stainless steel autoclave and kept in a muffle furnace at 150°C for 24 h. After washing with ethanol three times, the mixture was placed in a vacuum drying oven at 60°C overnight to obtain a Ni / Fe-MOF precursor. (2) placing 0.5 g of Ni / Fe-MOF precursor into a tube furnace for carbonization, maintaining it at 700-900 °C for 3 h at a heating rate of 3 °C / min to obtain the catalyst; (3) The prepared catalyst Ni3Fe / Ni / NiFe2O4@C was ball-milled with MgH2 powder at a mass ratio of 9:1 for 6 h at 500 rpm in a vacuum milling jar maintained under an argon atmosphere. The ball-to-powder ratio was (30-120):
1. To prevent overheating, the mill was rotated for 20 min and then stopped for 10 min. The resulting MgH2-Ni3Fe / Ni / NiFe2O4@C composite was stored in an argon-filled glove box for subsequent performance testing.
2. The method for improving the hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4@C catalyst according to claim 1, characterized in that: The molar ratio of the nickel chloride hexahydrate, ferric chloride hexahydrate and terephthalic acid is 1:(2-3):(4-5).
3. The method for improving the hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4@C catalyst according to claim 1, characterized in that: When treating the Ni / Fe-MOF precursor, the precursor is heated at 150° C. for a certain time of 12 to 24 hours.
4. The method for improving the hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4@C catalyst according to claim 1, characterized in that: The different mass ratios of the Ni3Fe / Ni / NiFe2O4@C and MgH2 powder are 9.5:0.5, 9:1, and 8.5:1.
5.
5. The method for improving the hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4@C catalyst according to claim 1, characterized in that: The ball milling conditions include a ball milling time of 4 to 8 hours and a ball milling speed of 400 to 600 rpm.
6. The method for improving the hydrogen storage performance of magnesium hydride based on Ni3Fe / Ni / NiFe2O4@C catalyst according to claim 1, characterized in that: The argon atmosphere is a glove box atmosphere filled with argon.