Aerogel and hydrogen storage alloy blend and method of making

Abstract

The application provides an aerogel and hydrogen storage alloy blend and a preparation method thereof, the preparation method comprising the following steps: S01, ball milling after smelting a first alloy to obtain a hydrogen storage alloy powder; the smelting temperature is 700 DEG C to 1600 DEG C, the annealing temperature is 600 DEG C to 1200 DEG C, and the annealing time is 5 h to 12 h; S02, adding the hydrogen storage alloy powder of step S01 into a mixed dispersion liquid, reacting at 140 DEG C to 250 DEG C for 18 h to 27 h to obtain a hydrogel; 0 mg to 3 mg of hydrogen storage alloy powder is added into the mixed dispersion liquid per milliliter; S03, pretreating the hydrogel of step S02, and then freeze-drying to obtain the aerogel and hydrogen storage alloy blend. The prepared aerogel and hydrogen storage alloy blend has good hydrogen storage capacity and heat conduction performance, can be applied to hydrogen storage tanks under different pressures, and the elastic performance thereof can be adjusted according to actual needs to adapt to different application scenarios.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fuel cell technology, in particular to an aerogel and hydrogen storage alloy blend and a preparation method thereof. BACKGROUND

[0002] Hydrogen energy is a clean secondary energy and an ideal carrier of renewable primary energy. At present, the development and utilization of hydrogen energy mainly faces three problems of hydrogen production, hydrogen storage and utilization. Hydrogen storage is the key to the development and utilization of hydrogen energy. Compared with liquid hydrogen storage technology and gas hydrogen storage technology, solid hydrogen storage technology is widely used in hydrogen storage due to its advantages of large hydrogen storage volume density, convenient transportation, high safety, easy operation and the like. The hydrogen storage tank using hydrogen storage alloy as the storage medium has large storage density and can conveniently provide hydrogen source for fuel cells used in various occasions. However, the hydrogen storage alloy has problems of poor hydrogen storage capacity, poor heat conduction capacity, poor elasticity, high cost and the like, and it is difficult to meet the needs of actual use. SUMMARY

[0003] Based on this, the embodiments of the present application provide an aerogel and hydrogen storage alloy blend and a preparation method thereof, aiming at solving the problems of the existing hydrogen storage alloy, such as poor hydrogen storage capacity, poor heat conduction capacity, poor elasticity, high cost and the like, and difficulty in meeting the needs of actual use.

[0004] To achieve the above-mentioned purpose, on the one hand, the embodiments of the present application provide a preparation method of an aerogel and hydrogen storage alloy blend, comprising the following steps:

[0005] S01, melting and ball milling a first alloy to obtain a hydrogen storage alloy powder; the melting temperature is 700℃-1600℃, the annealing temperature is 600℃-1200℃, and the annealing time is 5h-12h;

[0006] S02, adding the hydrogen storage alloy powder of step S01 into a mixed dispersion liquid, reacting at 140℃-250℃ for 18h-27h to obtain a hydrogel; 0mg-3mg of the hydrogen storage alloy powder is added per milliliter of the mixed dispersion liquid;

[0007] S03, pretreating the hydrogel of step S02 and then freeze-drying to obtain an aerogel and hydrogen storage alloy blend.

[0008] As a preferred embodiment, in step S01,

[0009] The first alloy is a solid solution / light metal hydride / light metal coordination oxide of AB5 type, AB3 type, AB2 type, AB type or A2B type.

[0010] The first alloy is one of LaNi5, CaNi3, TiMn2, TiFe, Mg2Ni, Ti-V, MgH2 and Mg(BH4)2 or a mixture of at least two of them.

[0011] The melting temperature is 800-1400℃, the annealing temperature is 600-1000℃, and the annealing time is 6-12h.

[0012] The melting is preferably carried out in vacuum or inert gas atmosphere, the inert gas is argon, and the melting is carried out in a water-cooled copper crucible.

[0013] The number of melting is greater than or equal to three. In this way, the uniformity of the alloy composition can be well ensured.

[0014] The rotation speed of the ball milling is 200-600rpm, and the ball milling time is 24-96h.

[0015] As a preferred embodiment, in step S02,

[0016] The mixed dispersion liquid is prepared by dispersing carbon nanotubes in a first solvent to obtain a carbon nanotube dispersion liquid, mixing the graphene oxide dispersion liquid with the carbon nanotube dispersion liquid at a volume ratio of (0.5-20):1, stirring for 4-12h, and ultrasonicating for 0.5-6h to obtain the mixed dispersion liquid.

[0017] The first solvent is one of ethanol, tetrahydrofuran, acetone, dimethylformamide and petroleum ether or a mixture of at least two of them.

[0018] The concentration of carbon nanotubes in the carbon nanotube dispersion liquid is preferably 1-7mg / ml.

[0019] The graphene oxide dispersion liquid is a dispersion liquid obtained by dispersing graphene oxide in a second solvent.

[0020] The second solvent is one of ethanol, tetrahydrofuran, acetone, dimethylformamide and petroleum ether or a mixture of at least two of them.

[0021] The concentration of graphene oxide in the graphene oxide dispersion liquid is 3mg / ml.

[0022] The stirring time is preferably 5-8h, and the ultrasonicating time is preferably 0.5-1.5h.

[0023] The reaction temperature is preferably 160-200℃.

[0024] As a preferred embodiment, in step S03,

[0025] The pre-treatment is realized by placing the hydrogel in liquid nitrogen to freeze into a solid state.

[0026] The temperature of the freeze-drying is 50 DEG C, the pressure of the freeze-drying is 10 Pa, and the time of the freeze-drying is 12-72 h.

[0027] In another aspect, the present application also provides an aerogel and hydrogen storage alloy blend prepared by the above preparation method.

[0028] The present application can effectively solve the problems of the existing hydrogen storage alloy, such as poor hydrogen storage capacity, poor heat conduction capacity, poor elasticity, high cost, and the like, and it is difficult to meet the needs of actual use. The prepared aerogel and hydrogen storage alloy blend has good hydrogen storage capacity and heat conduction performance, can be applied to hydrogen storage tanks under different pressures, and the elasticity of the aerogel and hydrogen storage alloy blend can be adjusted according to actual needs to adapt to different application scenarios. The preparation method of the present application is simple, the preparation cost is low, the preparation time is short, the production efficiency is high, and it is easy to mass produce or large-scale produce.

[0029] The implementation, functional features and advantages of the present application will be further described in conjunction with the embodiments. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0031] It should be noted that if the present application involves directional indications (such as up, down, left, right, front, back, top, bottom, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between the components in a certain posture, and if the certain posture changes, the directional indications will also change accordingly.

[0032] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrated; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0033] It is to be noted that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or there can be an intervening element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there can be an intervening element.

[0034] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the realization of the person skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the protection scope required by the present application.

[0035] At present, the hydrogen storage tank using hydrogen storage alloy as storage medium has high storage density, and can conveniently provide hydrogen source for fuel cells used in various occasions. However, the hydrogen storage alloy has problems of poor hydrogen storage capacity, poor heat conduction capacity, poor elasticity, high cost and the like, and it is difficult to meet the needs of actual use. Based on this, it is necessary to provide an aerogel and hydrogen storage alloy blend and a preparation method thereof to solve the above technical problems.

[0036] To achieve the above-mentioned purpose, on the one hand, the present application provides a preparation method of an aerogel and hydrogen storage alloy blend, comprising the following steps:

[0037] S01, the first alloy is smelted and ball milled to obtain hydrogen storage alloy powder; the smelting temperature is 700-1600 DEG C (which can be 700 DEG C, 900 DEG C or 1600 DEG C, etc.), the annealing temperature is 600-1200 DEG C (which can be 600 DEG C, 900 DEG C or 1200 DEG C, etc.), and the annealing time is 5-12 h (which can be 5 h, 9 h or 12 h, etc.);

[0038] S02, the hydrogen storage alloy powder of step S01 is added into a mixed dispersion liquid, and reacted at 140-250 DEG C (which can be 140 DEG C, 200 DEG C or 250 DEG C, etc.) for 18-27 h (which can be 18 h, 20 h or 27 h, etc.) to obtain a hydrogel; 0-3 mg (which can be 0.1 mg, 1 mg or 3 mg, etc.) of hydrogen storage alloy powder is added per milliliter of the mixed dispersion liquid;

[0039] S03, the hydrogel of step S02 is pretreated and then freeze-dried to obtain an aerogel and hydrogen storage alloy blend.

[0040] As a preferred embodiment, in step S01,

[0041] The first alloy is a solid solution / light metal hydride / light metal coordination oxide of AB5 type, AB3 type, AB2 type, AB type or A2B type.

[0042] The first alloy is one of LaNi5, CaNi3, TiMn2, TiFe, Mg2Ni, Ti-V, MgH2 and Mg(BH4)2 or a mixture of at least two thereof.

[0043] The temperature of the melting is 800-1400℃, the annealing temperature is 600-1000℃, and the annealing time is 6-12h.

[0044] The melting is preferably carried out in vacuum or inert gas atmosphere; the inert gas is argon; and the melting is carried out in a water-cooled copper crucible.

[0045] The number of times of the melting is greater than or equal to three. In this way, the uniformity of the alloy composition can be well ensured.

[0046] The rotation speed of the ball milling is 200-600rpm, and the ball milling time is 24-96h.

[0047] As a preferred embodiment, in step S02,

[0048] The mixed dispersion liquid is prepared by dispersing carbon nanotubes in a first solvent to obtain a carbon nanotube dispersion liquid, mixing the graphene oxide dispersion liquid with the carbon nanotube dispersion liquid at a volume ratio of (0.5-20):1 (for example, 0.5:1, 5:1, 20:1, etc.), stirring for 4-12h (for example, 4h, 10h, 12h, etc.), and ultrasonicating for 0.5-6h (for example, 0.5h, 3h, 6h, etc.) to obtain the mixed dispersion liquid.

[0049] The first solvent is one or a mixture of at least two of ethanol, tetrahydrofuran, acetone, dimethylformamide and petroleum ether.

[0050] The concentration of the carbon nanotubes in the carbon nanotube dispersion liquid is preferably 1-7mg / ml (for example, 1mg / ml, 3mg / ml, 7mg / ml, etc.).

[0051] The graphene oxide dispersion liquid is a dispersion liquid obtained by dispersing graphene oxide in a second solvent.

[0052] The second solvent is one or a mixture of at least two of ethanol, tetrahydrofuran, acetone, dimethylformamide and petroleum ether.

[0053] The concentration of graphene oxide in the graphene oxide dispersion is 3 mg / ml.

[0054] The stirring time is preferably 5h-8h; the ultrasonic time is preferably 0.5h-1.5h.

[0055] The reaction temperature is preferably 160℃-200℃.

[0056] As a preferred embodiment, in step S03,

[0057] The pretreatment is achieved by placing the hydrogel in liquid nitrogen and freezing it into a solid state.

[0058] The freeze-drying temperature is 50℃, the freeze-drying pressure is 10Pa, and the freeze-drying time is 12h-72h.

[0059] In another aspect, the present application also provides an aerogel and hydrogen storage alloy blend prepared by the above preparation method.

[0060] The present application can effectively solve the problems of existing hydrogen storage alloys, such as poor hydrogen storage capacity, poor thermal conductivity, poor elasticity, high cost, and difficulty in meeting the needs of actual use. The prepared aerogel and hydrogen storage alloy blend has good hydrogen storage capacity and thermal conductivity, can be applied to hydrogen storage tanks under different pressures, and the elasticity of the aerogel and hydrogen storage alloy blend can be adjusted according to actual needs to adapt to different application scenarios. The preparation method of the present application is simple, has low preparation cost, short preparation time, high production efficiency, and is easy to mass produce or produce in large quantities.

[0061] Example 1

[0062] A preparation method of an aerogel and hydrogen storage alloy blend, comprising the following steps:

[0063] S01, after smelting the first alloy, ball milling (rotation speed 300rpm, time 48h) to obtain hydrogen storage alloy powder; the smelting temperature is 1300℃, the annealing temperature is 1000℃, and the annealing time is 10h;

[0064] S02, 0.10g of the hydrogen storage alloy powder of step S01 is added into 50ml of a mixed dispersion liquid, and reacted at 180℃ for 24h to obtain a hydrogel;

[0065] S03, the hydrogel of step S02 is pretreated and then freeze-dried to obtain an aerogel and hydrogen storage alloy blend.

[0066] In step S01,

[0067] The first alloy is CaNi3.

[0068] The smelting is carried out in a vacuum, inert gas atmosphere; the inert gas is argon; the smelting is carried out in a water-cooled copper crucible.

[0069] The number of times of smelting is equal to three. In this way, the uniformity of the alloy composition can be well ensured.

[0070] In step S02,

[0071] The mixed dispersion liquid is prepared by the following method: 0.15 g of carbon nanotubes is dispersed in 50 ml of a first solvent to obtain a carbon nanotube dispersion liquid; the graphene oxide dispersion liquid is mixed with the carbon nanotube dispersion liquid at a volume ratio of 9:1, stirred for 6 h, and ultrasonically treated for 1 h to obtain the mixed dispersion liquid.

[0072] The first solvent is ethanol.

[0073] The graphene oxide dispersion liquid is a dispersion liquid obtained by dispersing graphene oxide in a second solvent. The second solvent is ethanol.

[0074] The concentration of graphene oxide in the graphene oxide dispersion liquid is 3 mg / ml.

[0075] In step S03,

[0076] The pretreatment is achieved by the following method: the hydrogel is placed in liquid nitrogen and frozen into a solid state.

[0077] The temperature of the freeze-drying is 50°C, the pressure of the freeze-drying is 10 Pa, and the time of the freeze-drying is 24 h.

[0078] The hydrogen storage capacity of the aerogel and hydrogen storage alloy blend prepared is 2.2 wt.%.

[0079] Example 2

[0080] A method for preparing an aerogel and hydrogen storage alloy blend, comprising the following steps:

[0081] S01, after smelting the first alloy, ball milling (rotation speed 300 rpm, time 48 h) to obtain a hydrogen storage alloy powder; the temperature of the smelting is 1300°C, the annealing temperature is 1000°C, and the annealing time is 10 h;

[0082] S02, 0.05 g of the hydrogen storage alloy powder of step S01 is added to 50 ml of a mixed dispersion liquid, and reacted at 180°C for 24 h to obtain a hydrogel;

[0083] S03, the hydrogel of step S02 is pretreated and then freeze-dried to obtain an aerogel and hydrogen storage alloy blend.

[0084] In step S01,

[0085] The first alloy is CaNi3.

[0086] The smelting is carried out in vacuum or inert gas atmosphere; the inert gas is argon; the smelting is carried out in a water-cooled copper crucible.

[0087] The number of smelting is equal to three. In this way, the uniformity of the alloy composition can be well ensured.

[0088] In step S02,

[0089] The mixed dispersion liquid is prepared by the following method: 0.15 g of carbon nanotubes is dispersed in 50 ml of a first solvent to obtain a carbon nanotube dispersion liquid; the graphene oxide dispersion liquid is mixed with the carbon nanotube dispersion liquid at a volume ratio of 9:1, stirred for 6 h, and ultrasonically treated for 1 h to obtain a mixed dispersion liquid.

[0090] The first solvent is ethanol.

[0091] The graphene oxide dispersion liquid is a dispersion liquid obtained by dispersing graphene oxide in a second solvent. The second solvent is ethanol.

[0092] The concentration of graphene oxide in the graphene oxide dispersion liquid is 3 mg / ml.

[0093] In step S03,

[0094] The pretreatment is achieved by the following method: the hydrogel is placed in liquid nitrogen and frozen into a solid state.

[0095] The temperature of the freeze-drying is 50℃, the pressure of the freeze-drying is 10 Pa, and the time of the freeze-drying is 24 h.

[0096] The hydrogen storage capacity of the prepared aerogel and hydrogen storage alloy blend is 2.1 wt.%.

[0097] Example 3

[0098] A preparation method of an aerogel and hydrogen storage alloy blend, comprising the following steps:

[0099] S01, after smelting the first alloy, ball milling (rotation speed 300 rpm, time 48 h) to obtain hydrogen storage alloy powder; the smelting temperature is 1400℃, the annealing temperature is 1000℃, and the annealing time is 12 h;

[0100] S02, 0.05 g of hydrogen storage alloy powder of step S01 is added to 50 ml of a mixed dispersion liquid, and reacted at 180℃ for 24 h to obtain a hydrogel;

[0101] S03, the hydrogel of step S02 is pretreated and then freeze-dried to obtain an aerogel and hydrogen storage alloy blend.

[0102] In step S01,

[0103] The first alloy is LaNi5.

[0104] The smelting is performed in a vacuum, inert gas atmosphere; the inert gas is argon; the smelting is performed in a water-cooled copper crucible.

[0105] The number of smelting is equal to three. In this way, the uniformity of the alloy composition can be well guaranteed.

[0106] In step S02,

[0107] The mixed dispersion liquid is prepared by the following method: 0.15g carbon nanotubes are dispersed in 50ml of a first solvent to obtain a carbon nanotube dispersion liquid; the graphene oxide dispersion liquid is mixed with the carbon nanotube dispersion liquid at a volume ratio of 9:1, stirred for 6h, and ultrasonically treated for 1h to obtain a mixed dispersion liquid.

[0108] The first solvent is ethanol.

[0109] The graphene oxide dispersion liquid is a dispersion liquid obtained by dispersing graphene oxide in a second solvent. The second solvent is ethanol.

[0110] The concentration of graphene oxide in the graphene oxide dispersion liquid is 3mg / ml.

[0111] In step S03,

[0112] The pretreatment is achieved by the following method: the hydrogel is placed in liquid nitrogen and frozen into a solid state. The temperature of the freeze-drying is 50℃, the pressure of the freeze-drying is 10Pa, and the time of the freeze-drying is 24h.

[0113] The hydrogen storage capacity of the prepared aerogel and hydrogen storage alloy blend is 1.6wt.%.

[0114] Comparative Example 1

[0115] A method for preparing a hydrogen storage alloy powder, comprising the following steps:

[0116] The alloy LaNi5 is smelted and then ball milled (rotation speed 300rpm, time 48h) to obtain a hydrogen storage alloy powder; the smelting temperature is 1400℃, the annealing temperature is 1000℃, and the annealing time is 12h.

[0117] The smelting is performed in a vacuum, inert gas atmosphere; the inert gas is argon; the smelting is performed in a water-cooled copper crucible.

[0118] The number of melting is equal to three.

[0119] The hydrogen storage capacity of the prepared hydrogen storage alloy powder is 1.3 wt.%. It can be seen that the hydrogen storage capacity of the hydrogen storage alloy powder prepared in Comparative Example 1 is equivalent to the hydrogen storage capacity of general La alloy (about 1.3 wt.%).

[0120] Compared with Example 3, it can be seen that the aerogel and hydrogen storage alloy blend in Example 3 can significantly improve the hydrogen storage capacity of La alloy.

[0121] Comparative Example 2

[0122] A preparation method of a hydrogen storage alloy powder, comprising the following steps:

[0123] The alloy CaNi3 is melted and then ball milled (rotation speed 300 rpm, time 48 h) to obtain a hydrogen storage alloy powder; the melting temperature is 1300℃, the annealing temperature is 1000℃, and the annealing time is 12 h;

[0124] The melting is carried out in a vacuum or inert gas atmosphere; the inert gas is argon; and the melting is carried out in a water-cooled copper crucible.

[0125] The number of melting is equal to three.

[0126] The hydrogen storage capacity of the prepared hydrogen storage alloy powder is 1.7 wt.%.

[0127] It can be seen that the hydrogen storage capacity of the hydrogen storage alloy powder prepared in Comparative Example 2 is equivalent to the hydrogen storage capacity of general calcium alloy (about 1.8 wt.%).

[0128] Compared with Examples 1-2, it can be seen that the aerogel and hydrogen storage alloy blend in Examples 1-2 can significantly improve the hydrogen storage capacity of calcium alloy.

[0129] The above only describes the preferred embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made by using the content of the present application, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A method of making an aerogel and hydrogen storage alloy blend, characterized by, The method comprises the following steps: S01, melting and ball-milling a first alloy to obtain a hydrogen storage alloy powder; the melting temperature is 700-1600℃, the annealing temperature is 600-1200℃, and the annealing time is 5-12h; S02, adding the hydrogen storage alloy powder of step S01 into a mixed dispersion liquid, and reacting at 140-250℃ for 18-27h to obtain a hydrogel; 1-3mg of the hydrogen storage alloy powder is added into each milliliter of the mixed dispersion liquid; S03, pretreating the hydrogel of step S02, and freeze-drying to obtain an aerogel and hydrogen storage alloy blend; In step S02, the mixed dispersion liquid is prepared by the following method: dispersing carbon nanotubes in a first solvent to obtain a carbon nanotube dispersion liquid; mixing the graphene oxide dispersion liquid and the carbon nanotube dispersion liquid at a volume ratio of (0.5-20):1, stirring for 4-12h, and ultrasonicating for 0.5-6h to obtain the mixed dispersion liquid; The first solvent is a mixture of one or at least two of ethanol, tetrahydrofuran, acetone, dimethylformamide, and petroleum ether; The graphene oxide dispersion liquid is a dispersion liquid obtained by dispersing graphene oxide in a second solvent; the second solvent is a mixture of one or at least two of ethanol, tetrahydrofuran, acetone, dimethylformamide, and petroleum ether; In step S03, the pretreatment is performed using liquid nitrogen; The freeze-drying temperature is 50℃, the freeze-drying pressure is 10Pa, and the freeze-drying time is 12-72h.

2. The method of claim 1, wherein the aerogel and hydrogen storage alloy blend is prepared by the steps of: In step S01, the first alloy is a solid solution / light metal hydride / light metal coordination oxide of AB5 type, AB3 type, AB2 type, AB type, or A2B type.

3. The method of claim 1, wherein the aerogel and hydrogen storage alloy blend is prepared by the steps of: The first alloy is one or at least two of LaNi5, CaNi3, TiMn2, TiFe, Mg2Ni, Ti-V, MgH2, and Mg(BH4)2. In step S01, the melting temperature is 800-1400℃, the annealing temperature is 600-1000℃, and the annealing time is 6-12h; the melting is performed in a vacuum or an inert gas atmosphere; the ball-milling speed is 200-600rpm, and the ball-milling time is 24-96h.

4. The method of claim 1, wherein the aerogel and hydrogen storage alloy blend is prepared by the steps of: The concentration of carbon nanotubes in the carbon nanotube dispersion liquid is 1-7mg / ml.

5. The method of claim 1, wherein the aerogel and hydrogen storage alloy blend is prepared by the steps of: The concentration of graphene oxide in the graphene oxide dispersion liquid is 3mg / ml.

6. The method of claim 1, wherein the aerogel and hydrogen storage alloy blend is prepared by the steps of: The aerogel and hydrogen storage alloy blend is prepared by the preparation method of any one of claims 1-6.

7. An aerogel and hydrogen storage alloy blend, characterized in that, ​