A ternary metal hydrogen-rich material and its preparation method

Abstract

The present invention discloses a ternary metal hydrogen-rich material and a preparation method thereof, belonging to the technical field of hydrogen storage. It is used to solve the problems that the types of existing ternary hydrides are few and the preparation conditions are harsh. The chemical formula of the ternary metal hydrogen-rich material of the present invention is Mg2TH6, Ca2BH6, Sr2AH6 or Ba2MH6, where T is Co, Rh, Ir, Pd or Pt, B is Co, Ni, Os, Rh, Ir, Pd or Pt, A is Fe, Co, Ni, Os, Rh, Ir or Pd, and M is Fe, Co, Ni, Os, Rh, Ir or Pd. The ternary metal hydrogen-rich material of the present invention has a high hydrogen content and is thermodynamically stable, and still stably exists under normal pressure, further broadening the material system of hydrogen storage materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen storage. Specifically, it relates to a ternary metal hydrogen-rich material and a preparation method thereof. Background Art

[0002] In the field of hydrogen storage, ternary hydrides contain additional atoms or molecules, which can provide more hydrogen storage sites and usually have a higher hydrogen storage capacity than binary hydrides. And due to the addition of extra elements, ternary hydrides generally have better cycle stability. They show a lower degradation rate during multiple cycles of hydrogen absorption / desorption, thus extending the service life and reliability of the material. In the prior art, the types of ternary hydrides prepared are few, and the preparation conditions are harsh, and some metal hydrogen-rich materials with high hydrogen content cannot be recovered under conventional conditions. Summary of the Invention

[0003] The purpose of the present invention is to provide a ternary metal hydrogen-rich material and a preparation method thereof to solve one of the following technical problems: In the prior art, the types of ternary hydrides prepared are few, the preparation conditions are harsh, and some metal hydrogen-rich materials with high hydrogen content cannot be recovered under conventional conditions.

[0004] The above object of the present invention is achieved by the following technical solutions:

[0005] On the one hand, the present invention provides a ternary metal hydrogen-rich material, and the chemical formula of the ternary metal hydrogen-rich material is Mg2TH6, Ca2BH6, Sr2AH6 or Ba2MH6, where T is Co, Rh, Ir, Pd or Pt, B is Co, Ni, Os, Rh, Ir, Pd or Pt, A is Fe, Co, Ni, Os, Rh, Ir or Pd, and M is Fe, Co, Ni, Os, Rh, Ir or Pd.

[0006] Further, the lattice parameter a of the ternary metal hydrogen-rich material is

[0007] Further, the ternary metal hydrogen-rich material can stably exist under normal pressure.

[0008] The present invention also provides a preparation method of the above ternary metal hydrogen-rich material, and the preparation method includes the following steps:

[0009] S1. Encapsulate the raw materials in an inert metal cylinder, and then place them in a high-pressure cavity;

[0010] S2. Pressurize the raw materials. After reaching the target pressure, start heating and keep the pressure and temperature constant;

[0011] S3. Perform quenching treatment under high pressure: Lower the temperature of the sample position to room temperature, and obtain the ternary metal hydrogen-rich material after depressurization.

[0012] Further, in S1, the raw materials include a hydrogen source material, a material containing Mg, Ca, Sr, or Ba, and a material containing Fe, Co, Ni, Ru, Os, Rh, Ir, Pd, or Pt.

[0013] Further, in S1, the inert metal cylinder is made of tantalum, stainless steel, gold, or platinum.

[0014] Further, in S2, the target pressure range is 1 - 30 GPa.

[0015] Further, in S2, the target temperature range is 800 - 1200 °C.

[0016] Further, in S3, the cooling rate of the quenching treatment is 80 - 200 °C / s.

[0017] Further, in S3, the pressure relief rate is 1 GPa / h - 10 GPa / h.

[0018] Compared with the prior art, the present invention can at least achieve one of the following beneficial effects:

[0019] 1) The ternary metal hydrogen-rich material provided by the present invention has a high hydrogen content, enhances the energy density of the metal hydride material, and is thermodynamically stable, still stably existing under normal pressure, which provides great convenience for the in-situ structure and electrical property characterization of the ternary metal hydride material under normal pressure and high pressure, and further broadens the material system of hydrogen storage materials.

[0020] 2) In the preparation method of the ternary metal hydrogen-rich material provided by the present invention, the preparation pressure is 1 GPa - 30 GPa, the preparation pressure is relatively low and easy to achieve; the method of the present invention has a fast reaction rate, can shorten the reaction time, improve the synthesis efficiency, and can also obtain a pure metal hydride product. Through the preparation method of the present invention, the repeatability of the experiment is guaranteed, the experimental difficulty is reduced, and it becomes an important technology for the new metal hydride material to move towards application.

[0021] Other features and advantages of the present invention will be described in subsequent embodiments, and some can be obtained obviously from the specification, or understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the written specification and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings are only for the purpose of showing specific embodiments, and are not considered as a limitation to the present invention. Throughout the drawings, the same reference signs represent the same content.

[0023] Figure 1 It is the X-ray diffraction pattern of Mg2RhH6 in Example 1 of the present invention;

[0024] Figure 2 X-ray diffraction pattern of Mg2IrH6 for Example 2 of the present invention;

[0025] Figure 3 Graph of the magnetic property of Mg2IrH6 for Example 2 of the present invention varying with temperature;

[0026] Figure 4 Graph of the resistance of Ca2PdH6 for Example 3 of the present invention varying with temperature;

[0027] Figure 5 Graph of the magnetic property of Ca2PdH6 for Example 3 of the present invention varying with temperature;

[0028] Figure 6 Graph of the magnetic property of Sr2OsH6 for Example 4 of the present invention varying with temperature. Detailed implementation manners

[0029] The following combines the accompanying drawings to specifically describe the preferred embodiments of the present invention. Among them, the accompanying drawings form a part of the present invention and are used together with the embodiments of the present invention to explain the principle of the present invention.

[0030] The present invention provides a ternary metal rich-hydrogen material. The chemical formula of the ternary metal rich-hydrogen material is Mg2TH6, Ca2BH6, Sr2AH6 or Ba2MH6, where T is Co, Rh, Ir, Pd or Pt, B is Co, Ni, Os, Rh, Ir, Pd or Pt, A is Fe, Co, Ni, Os, Rh, Ir or Pd, and M is Fe, Co, Ni, Os, Rh, Ir or Pd.

[0031] Specifically, the present invention also provides a preparation method of the above ternary metal rich-hydrogen material, including the following steps:

[0032] S1. Encapsulate the raw materials in an inert metal cylinder, and then place it in a high-pressure cavity;

[0033] S2. Apply pressure to the raw materials. After reaching the target pressure, start heating and maintain the pressure and temperature;

[0034] S3. Perform quenching treatment under high-pressure conditions: rapidly reduce the temperature at the location of the sample to room temperature, and obtain the ternary metal rich-hydrogen material after pressure relief.

[0035] Specifically, in S1, the raw materials include a hydrogen source material, a material containing Mg, Ca, Sr or Ba, and a material containing Fe, Co, Ni, Ru, Os, Rh, Ir, Pd or Pt.

[0036] Specifically, in S1, the hydrogen source material includes solid hydrogen-containing materials such as borane ammonia complex and paraffin, and the hydrogen decomposition temperature thereof is lower than 800°C.

[0037] Specifically, in S1, the material containing Mg, Ca, Sr or Ba includes corresponding metal elements, metal hydrides and the like.

[0038] Specifically, in S1, the material containing Fe, Co, Ni, Ru, Os, Rh, Ir, Pd or Pt includes corresponding metal elements, metal hydrides, etc.

[0039] Specifically, in S1, the inert metal cylinder containing the raw materials is made of tantalum, stainless steel, gold, platinum, etc., which is not easy to react with hydrogen and can prevent hydrogen leakage during high-pressure and high-temperature reactions, thereby ensuring a higher hydrogen content in the product.

[0040] Specifically, before S1, the preparation work for high-voltage assembly is completed, including the following steps:

[0041] Select the corresponding high-pressure equipment according to the synthetic pressure of the target material. The high-pressure equipment includes a six-sided top press and a two-stage push press. According to the type of high-pressure equipment, select the corresponding high-pressure assembly, including the pressure transmission medium, sample chamber, heating component, inert metal cylinder, thermocouple, etc.

[0042] Specifically, in S1, the assembling method of the raw materials includes uniformly mixing the raw materials.

[0043] Taking into account the sufficiency of the raw material reaction and the difficulty of stripping the sample by-products, in S1, the raw materials can be assembled in a "sandwich" manner with hydrogen source materials placed at the bottom and top and the remaining raw materials placed in the middle.

[0044] Specifically, in S1, the high-pressure device may be a six-sided top press device, and at this time, pyrophyllite cubes may be selected as the pressure transmission medium.

[0045] Specifically, S1 includes completing the assembly of the pyrophyllite cube, including:

[0046] S01. A pyrophyllite cube with a side length of 25 to 30 mm (eg, 28 mm) is used as a pressure transmission medium, and a circular hole with a diameter of 8 to 10 mm is punched at the center of the pyrophyllite cube;

[0047] S02. The ground and mixed raw materials are placed in an inert metal cylinder;

[0048] S03. Place the inert metal cylinder into the boron nitride insulation layer;

[0049] S04. A graphite furnace is placed on the outside of the boron nitride insulation layer;

[0050] S05. Place the graphite furnace in the central round hole of the pyrophyllite, and successively place a graphite sheet, a molybdenum sheet, and a steel cap at both ends.

[0051] Specifically, in S01, the drilling can be carried out by mechanical drilling.

[0052] Specifically, in S02, the diameter of the inert metal cylinder is 5 - 7 mm, and the thickness is 0.4 - 0.6 mm.

[0053] Specifically, in S03, place the inert metal cylinder at the central position of the boron nitride thermal insulation layer, and fill both ends with boron nitride columns to achieve the thermal insulation effect.

[0054] Specifically, in S2, the target pressure range is 1 - 30 GPa. For example, the pressure is 1 GPa, 2 GPa, 3 GPa, 4 GPa, 5 GPa, 6 GPa, 7 GPa, 8 GPa, 9 GPa, 10 GPa, 11 GPa, 12 GPa, 13 GPa, 14 GPa, 15 GPa, 16 GPa, 17 GPa, 18 GPa, 19 GPa, 20 GPa, 21 GPa, 22 GPa, 23 GPa, 24 GPa, 25 GPa, 26 GPa, 27 GPa, 28 GPa, 29 GPa, 30 GPa.

[0055] Specifically, in S2, the target temperature range is 800 - 1200 °C, such as 800 °C, 900 °C, 1000 °C, 1100 °C, 1200 °C.

[0056] Specifically, in S2, the heat preservation time is 20 min - 4 h, such as 20 min, 30 min, 40 min, 50 min, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h.

[0057] Specifically, in S3, the cooling rate of the quenching treatment is 80 - 200 °C / s.

[0058] Specifically, in S3, the pressure relief speed is 1 GPa / h - 10 GPa / h. For example, 1.5 GPa / h, 2 GPa / h, 2.5 GPa / h, 3 GPa / h, 3.5 GPa / h, 4 GPa / h, 4.5 GPa / h, 5 GPa / h, 5.5 GPa / h, 6 GPa / h, 6.5 GPa / h, 7 GPa / h, 7.5 GPa / h, 8 GPa / h, 8.5 GPa / h, 9 GPa / h, 9.5 GPa / h.

[0059] Specifically, when the ternary metal hydrogen-rich material is Mg2RhH6, the target pressure is 2 - 8 GPa, the target temperature is 800 - 900 °C, and the heat preservation time is 20 - 120 min.

[0060] Specifically, when the ternary metal hydrogen-rich material is Mg2IrH6, the target pressure is 3 to 8 GPa, the target temperature is 800 to 900 °C, and the heat preservation time is 20 to 120 min.

[0061] Specifically, when the ternary metal hydrogen-rich material is Ca2PdH6, the target pressure is 4 to 9 GPa, the target temperature is 850 to 950 °C, and the heat preservation time is 20 to 120 min.

[0062] Specifically, when the ternary metal hydrogen-rich material is Sr2OsH6, the target pressure is 4 to 9 GPa, the target temperature is 850 to 950 °C, and the heat preservation time is 20 to 120 min.

[0063] Specifically, when the ternary metal hydrogen-rich material is Ba2IrH6, the target pressure is 4 to 9 GPa, the target temperature is 800 to 900 °C, and the heat preservation time is 20 to 120 min.

[0064] Specifically, the lattice parameter a of the ternary metal hydrogen-rich material of the present invention is The unit cell volume is

[0065] Specifically, the ternary metal hydrogen-rich material of the present invention has a high hydrogen content and is thermodynamically stable, and still stably exists under normal pressure, which provides great convenience for the in-situ structure and electrical property characterization of ternary metal hydride materials under normal pressure and high pressure, and further broadens the material system of hydrogen storage materials.

[0066] Example 1

[0067] This example provides a ternary metal hydrogen-rich material Mg2RhH6.

[0068] Specifically, for the Mg2RhH6 provided in this example, through crystal structure characterization, its lattice parameter The unit cell volume

[0069] The preparation method of Mg2RhH6 in this example includes the following steps:

[0070] S1. Encapsulate the raw materials in an inert metal cylinder, and then place it in a high-pressure cavity;

[0071] S2. Pressurize the raw materials. After reaching the target pressure, start heating and keep the pressure and temperature constant;

[0072] S3. Perform quenching treatment under high-pressure conditions to rapidly reduce the temperature at the position of the sample to room temperature, and obtain Mg2RhH6 after pressure relief.

[0073] Specifically, in S1, the raw materials include borane ammonia complex, Rh, and MgH2. The molar ratio of borane ammonia complex, Rh, and MgH2 is 2:1:2.

[0074] Specifically, the material of the above-mentioned inert metal cylinder is gold.

[0075] Specifically, the above-mentioned preparation method is carried out in a high-pressure device, and the high-pressure device is a six-sided top press device.

[0076] Specifically, S1 also includes: completing the assembly of the pyrophyllite cube, and the assembly of the pyrophyllite cube includes:

[0077] S01. Using a pyrophyllite cube with a side length of 28 mm as the pressure transfer medium, and drilling a circular hole with a diameter of 10 mm at the center position;

[0078] S02. Putting the ground and mixed raw materials into the inert metal cylinder;

[0079] S03. Putting the sample into the boron nitride heat preservation layer;

[0080] S04. Putting a graphite furnace outside the boron nitride heat preservation layer;

[0081] S05. Placing the graphite furnace in the central circular hole of the pyrophyllite, and successively placing graphite sheets, molybdenum sheets, and steel caps at both ends.

[0082] Specifically, in S01, the drilling is carried out by mechanical drilling.

[0083] Specifically, in S02, the assembly method of the raw materials selects the "sandwich" assembly structure with Rh and MgH2 placed in the middle of the metal cylinder and borane ammonia complex placed at both ends.

[0084] Specifically, in S02, the diameter of the inert metal cylinder is 6 mm and the thickness is 0.5 mm.

[0085] Specifically, in S2, during pressurization, the six top hammers on the top, bottom, left, right, front, and back synchronously extrude the cubic sample assembly block under the push of oil pressure, thereby generating high pressure in the sample cavity.

[0086] Specifically, in S2, the target pressure is 3 GPa,

[0087] Specifically, in S2, the target temperature is 860 °C and the heat preservation time is 30 min.

[0088] Specifically, in S3, the cooling rate of the quenching treatment is 150 °C / s, and rapid cooling is achieved by controlling the cooling water temperature.

[0089] Specifically, in S3, the pressure relief speed is 1 GPa / h.

[0090] The X-ray diffraction pattern and crystal structure diagram of the Mg2RhH6 sample synthesized under high pressure in this embodiment are as follows Figure 1 shown. Mg2RhH6 has a cubic crystal system structure and is composed of octahedra [RhH6] 3- and Mg 2+ cations. The lattice parameter The unit cell volume is Among them, [RhH6] 3- The octahedral structure is composed of rhodium ions at the center of the octahedron and the surrounding hydrogen. This bonding form helps to improve the energy density and stability of the material.

[0091] The Mg2RhH6 in this embodiment has a high hydrogen content, enhancing the energy density of the metal-rich hydride material, and is thermodynamically stable and still stably exists under normal pressure, providing great convenience for the in-situ structure and electrical property characterization of ternary metal-rich hydride materials under normal pressure and high pressure, and further broadening the material system of hydrogen storage materials.

[0092] Example 2

[0093] This embodiment provides a ternary metal-rich hydrogen material Mg2IrH6.

[0094] The preparation method of Mg2IrH6 in this embodiment includes the following steps:

[0095] S1. Encapsulate the raw materials in an inert metal cylinder and then place them in a high-pressure cavity;

[0096] S2. Pressurize the raw materials. After reaching the target pressure, start heating and keep the pressure and temperature constant;

[0097] S3. Perform quenching treatment under high pressure to quickly reduce the temperature at the position of the sample to room temperature, and obtain Mg2IrH6 after depressurization.

[0098] Specifically, in S1, the raw materials include borane ammonia complex, Ir, and MgH2. The molar ratio of borane ammonia complex, Ir, and MgH2 is 2:1:2.

[0099] Specifically, the material of the above-mentioned inert metal cylinder is gold.

[0100] Specifically, the above method is carried out in a six-anvil press device, which is the same as that in Example 1 and will not be elaborated here.

[0101] Specifically, in S2, the target pressure is 5 GPa,

[0102] Specifically, in S2, the target temperature is 820 °C and the heat preservation time is 30 min.

[0103] Specifically, in S3, the cooling rate of the quenching treatment is 150 °C / s.

[0104] Specifically, in S3, the pressure relief rate is 1 GPa / h.

[0105] The X-ray diffraction pattern and crystal structure diagram of the Mg2IrH6 sample synthesized under high pressure in this example are as Figure 2 shown. Mg2IrH6 has a cubic crystal system structure and consists of octahedra [IrH6] 3- and Mg 2+ cations. The lattice parameter unit cell volume

[0106] The Mg2IrH6 in this example has a high hydrogen content, enhancing the energy density of the metal-rich hydride material. It is thermodynamically stable and still stably exists under atmospheric pressure, providing great convenience for the in-situ structure and electrical property characterization of ternary metal-rich hydride materials under atmospheric and high pressures, and further broadening the material system of hydrogen storage materials.

[0107] The magnetic properties of the Mg2IrH6 in this example are as Figure 3 shown. The variation of the magnetization intensity with temperature under an external magnetic field strength of 30 Oe. The M-T test results show a diamagnetic signal transition at 7 K.

[0108] Example 3

[0109] This example first provides a ternary metal-rich hydride material Ca2PdH6.

[0110] The preparation method of the Ca2PdH6 in this example includes the following steps:

[0111] S1. Enclose the raw materials in an inert metal cylinder and then place it in a high-pressure cavity.

[0112] S2. Pressurize the raw materials. After reaching the target pressure, start heating and keep the pressure and temperature constant.

[0113] S3. Conduct a quenching treatment under high pressure to rapidly reduce the temperature at the location of the sample to room temperature, and obtain Ca2PdH6 after pressure relief.

[0114] Specifically, in S1, the raw materials include borane ammonia complex, Pd, and CaH2. The molar ratio of borane ammonia complex, Pd, and CaH2 is 2:1:2.

[0115] Specifically, the material of the above-mentioned inert metal cylinder is gold.

[0116] Specifically, the above method is carried out in a six-sided top press device, which is the same as that in Example 1 and will not be elaborated here.

[0117] Specifically, in S2, the target pressure is 5.5 GPa, the target temperature is 900 °C, and the heat preservation time is 30 min.

[0118] Specifically, in S3, the cooling rate of the quenching treatment is 150 °C / s, and rapid cooling is achieved by controlling the cooling water temperature.

[0119] Specifically, in S3, the pressure relief rate is 1 GPa / h.

[0120] The Ca2PdH6 in this embodiment has a high hydrogen content, enhancing the energy density of the metal-rich hydride material, and is thermodynamically stable, still stably existing under normal pressure, providing great convenience for the in-situ structure and electrical property characterization of ternary metal-rich hydride materials under normal pressure and high pressure, and further broadening the material system of hydrogen storage materials.

[0121] The electrical test diagram of Ca2PdH6 in this embodiment is as Figure 4 shown. The resistivity decreases with the increase of temperature, proving that Ca2PdH6 is a semiconductor. It broadens the material system of semiconductor materials.

[0122] The magnetic properties of Ca2PdH6 in this embodiment are as Figure 5 shown. The variation of the magnetization intensity with temperature under an external magnetic field strength of 30 Oe. The M-T test results show a ferrimagnetic signal at low temperatures.

[0123] Example 4

[0124] This embodiment provides a ternary metal-rich hydrogen material Sr2OsH6.

[0125] The preparation method of Sr2OsH6 in this embodiment includes the following steps:

[0126] S1. Encapsulate the raw materials in an inert metal cylinder, and then place it in a high-pressure cavity.

[0127] S2. Pressurize the raw materials. After reaching the target pressure, start heating and keep the pressure and temperature.

[0128] S3. Perform quenching treatment under high pressure to rapidly reduce the temperature at the position of the sample to room temperature, and obtain Sr2OsH6 after pressure relief.

[0129] Specifically, in S1, the raw materials include borane ammonia complex, Os, and SrH2. The molar ratio of borane ammonia complex, Os, and SrH2 is 2:1:2.

[0130] Specifically, the material of the above inert metal cylinder is gold.

[0131] Specifically, the above method is carried out in a six-sided top press device, which is the same as that in Example 1 and will not be elaborated here.

[0132] Specifically, in S2, the target pressure is 5 GPa, the target temperature is 900 °C, and the heat preservation time is 30 min.

[0133] Specifically, in S3, the cooling rate of the quenching treatment is 150 °C / s, and rapid cooling is achieved by controlling the cooling water temperature.

[0134] Specifically, in S3, the pressure relief rate is 1 GPa / h.

[0135] The Sr2OsH6 of this embodiment has a high hydrogen content, enhances the energy density of the metal hydride material, and is thermodynamically stable, remaining stable under normal pressure. It provides great convenience for the in-situ structure and electrical property characterization of ternary metal hydride materials under normal and high pressures, further broadening the material system of hydrogen storage materials.

[0136] The magnetic properties of the Sr2OsH6 of this embodiment are as Figure 5 shown in the variation of the magnetization intensity with temperature under an external magnetic field strength of 30 Oe. The M-T test results show a ferrimagnetic signal at low temperatures.

[0137] Example 5

[0138] This embodiment provides a ternary metal hydride material Ba2IrH6.

[0139] The preparation method of the Ba2IrH6 of this embodiment includes the following steps:

[0140] S1. Encapsulate the raw materials in an inert metal cylinder, and then place it in a high-pressure cavity.

[0141] S2. Pressurize the raw materials. After reaching the target pressure, start heating and keep the pressure and temperature constant.

[0142] S3. Perform quenching treatment under high-pressure conditions to rapidly reduce the temperature at the location of the sample to room temperature, and obtain Ba2IrH6 after pressure relief.

[0143] Specifically, in S1, the raw materials include borane ammonia complex, Ir, and BaH2. The molar ratio of borane ammonia complex, Ir, and BaH2 is 2:1:2.

[0144] Specifically, the material of the above-mentioned inert metal cylinder is gold.

[0145] Specifically, the above method is carried out in a six-sided top press device, which is the same as that in Example 1 and will not be elaborated here.

[0146] Specifically, in S2, the target pressure is 5.5 GPa, the target temperature is 850 °C, and the heat preservation time is 30 min.

[0147] Specifically, in S3, the cooling rate of the quenching treatment is 150 °C / s, and rapid cooling is achieved by controlling the cooling water temperature.

[0148] Specifically, in S3, the pressure relief rate is 1 GPa / h.

[0149] The Ba2IrH6 in this embodiment has a high hydrogen content, enhancing the energy density of the metal-rich hydride material, and is thermodynamically stable, remaining stable under normal pressure, which provides great convenience for the in-situ structure and electrical property characterization of ternary metal-rich hydride materials under normal and high pressures, and further broadens the material system of hydrogen storage materials.

[0150] During the research process, the inventors conducted a large number of experimental studies, and some solutions with poor effects are now used as comparative examples.

[0151] Comparative Example 1

[0152] This comparative example provides a preparation method of a hydride material. The overall steps are the same as those in Example 1, except that:

[0153] In step S2, the target temperature is 400 °C. What is obtained in this comparative example is MgH2, MgRhH 0.61 and unknown impurity phases.

[0154] Comparative Example 2

[0155] This comparative example provides a preparation method of a hydride material. The overall steps are the same as those in Example 1, except that:

[0156] In step S2, the target pressure is 10 GPa. What is obtained in this comparative example is MgRhH 0.61 , MgRhH 0.94 and unknown impurity phases.

[0157] Comparative Example 3

[0158] This comparative example provides a preparation method of a hydride material. The overall steps are the same as those in Example 2, except that:

[0159] In step S2, the target temperature is 450 °C. What is obtained in this comparative example is MgH2, Ir, IrO2 and unknown impurity phases.

[0160] Comparative Example 4

[0161] This comparative example provides a preparation method of a hydride material. The overall steps are the same as those in Example 2, except that:

[0162] In step S1, the molar ratio of the metal dihydride MgH2, the metal element Ir and the hydrogen source material borane ammonia complex is 2:1:0.5. What is obtained in this comparative example is IrO2, Ir and unknown impurity phases.

[0163] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A preparation method of a ternary metal hydrogen-rich material, characterized in that, The preparation method comprises the following steps: S1. Enclose the raw materials in an inert metal cylinder, and then place it in a high-pressure cavity; S2. Apply pressure to the raw materials. After reaching the target pressure, start heating and maintain the pressure and temperature; S3. Conduct quenching treatment under high pressure: lower the temperature at the position where the sample is located to room temperature, and obtain the ternary metal hydrogen-rich material after depressurization; The ternary metal hydrogen-rich materials are Ca2PdH6 and Ba2IrH6; In S1, the raw materials include a hydrogen source material, a material containing Ca or Ba, and a material containing Ir or Pd; When the ternary metal hydrogen-rich material is Ca2PdH6, the target pressure is 4-9 GPa and the target temperature is 850-950 °C; When the ternary metal hydrogen-rich material is Ba2IrH6, the target pressure is 4-9 GPa and the target temperature is 800-900 °C; The preparation pressure in the preparation method is relatively low, and the ternary metal hydrogen-rich material can stably exist under normal pressure.

2. The preparation method according to claim 1, wherein In S1, the material of the inert metal cylinder is tantalum, stainless steel, gold or platinum.

3. The preparation method according to claim 1, characterized in that, In S3, the cooling rate of the quenching treatment is 80-200 °C / s.

4. The preparation method according to any one of claims 1 to 3, characterized in that, In S3, the depressurization rate is 1 GPa / h to 10 GPa / h.

5. A ternary metal hydrogen-rich material, characterized in that, The ternary metal hydrogen-rich material is prepared by the preparation method described in any one of claims 1 to 4.

6. The ternary metal hydrogen-rich material according to claim 5, characterized in that, The lattice parameter a of the ternary metal hydrogen-rich material is 6.4 Å to 8 Å.

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