CN116377303B

CN116377303B - A cheap, high-capacity, high-entropy hydrogen storage alloy and its preparation method

Info

Publication number: CN116377303B
Application number: CN202211728508.4A
Authority: CN
Inventors: 李丽荣; 罗龙; 刘素霞; 李永治; 陈良攀
Original assignee: Inner Mongolia University of Science and Technology
Current assignee: Inner Mongolia University of Science and Technology
Priority date: 2022-12-30
Filing date: 2022-12-30
Publication date: 2025-05-06
Anticipated expiration: 2042-12-30
Also published as: CN116377303A

Abstract

The present invention provides a low-cost, high-capacity, high-entropy hydrogen storage alloy and a preparation method thereof. The hydrogen storage alloy is composed of five elements, namely, _vanadium , titanium, _chromium , iron and manganese, and its chemical formula _composition is calculated by _molar ratio as follows: _{VaTibCrcFedMne} , wherein 34≤a≤36, 34≤b≤36 , 9≤c≤11 , 9≤d≤11 , 9≤e≤11 , and a + b + c+d+e =100. The alloy solves the problems of high cost and poor hydrogen absorption kinetics of vanadium-titanium based solid solution alloys. The hydrogen storage alloy belongs to a solid solution high-entropy alloy, has ultrafast hydrogen absorption kinetics, high hydrogen absorption capacity, easy activation, low cost, and a simple and traditional production method.

Description

Low-cost high-capacity high-entropy hydrogen storage alloy and preparation method thereof

Technical Field

The invention relates to the technical field of hydrogen storage alloys, in particular to a low-cost high-capacity and ultra-fast hydrogen absorption high-entropy hydrogen storage alloy and a preparation method thereof, and particularly relates to a high-entropy solid solution hydrogen storage alloy consisting of multiple elements of vanadium, titanium, chromium, iron and manganese and a preparation method thereof.

Background

The main energy source for human survival has been evolving with the development of social activities. The world today relies heavily on fossil fuels (coal, oil, natural gas, etc.). Population growth and lifestyle improvement have led to rapid increases in energy demand since 1950. It is estimated that by 2035, energy shortages and large amounts of greenhouse gas emissions become more and more severe in the course of fossil fuel consumption with the development of society, which greatly restricts economic green and sustainable development. Thus, the search for sustainable and clean energy has become a search for scientists. There are many renewable energy sources on earth, such as solar energy, wind energy, tidal energy, biomass energy, wave energy and geothermal energy, which are being intensively explored and studied. Among these potential candidates, hydrogen is considered the best energy carrier to meet the overall CO ₂ abatement objectives because of its high energy density (120 MJ/kg), environmental friendliness and high abundance on earth.

Hydrogen is a flammable and explosive reactive gas. In the whole hydrogen energy industry chain of "production, storage, transmission and use", hydrogen storage is a key link of "hydrogen economy", so that it is necessary to develop a safe, low-cost and compact hydrogen storage system. The hydrogen storage method mainly comprises gaseous, liquid and solid hydrogen storage. In contrast, solid-state hydrogen storage is considered as a direction of large-scale hydrogen energy storage and transportation in the future because of the advantages of safety in storage, convenience in transportation, high storage density and the like.

The metal hydride solid-state hydrogen storage method has the advantages of high hydrogen storage density, good safety, convenient operation, low running cost and the like, and is considered to be the most ideal hydrogen storage method. As a hydrogen storage material, the vanadium-titanium base BCC (Body Centred Cubic, body centered cubic) structural alloy has the advantages of high hydrogen storage density, good anti-powdering performance, capability of absorbing and releasing hydrogen at normal temperature and normal pressure, and the like. The vanadium-titanium-based hydrogen storage alloy developed at present is mainly a V-Ti-Mn, V-Ti-Cr, V-Ti-Fe and V-Ti-Ni series multicomponent alloy. Among them, V-Ti-Cr series alloy has higher capacity, good cycle performance and hydrogen absorption and desorption kinetics, and is considered as the most promising candidate material. However, in order to maintain high capacity, the existing vanadium-titanium-based solid solution alloy has a high proportion of vanadium element, and the cost is a big problem which hinders the application of the vanadium-titanium-based solid solution alloy. And the hydrogen absorption dynamic performance is poor, and the hydrogen absorption time is at least 5 minutes. For example, the hydrogen absorption of the hydrogen storage alloy V-Ti-Fe alloy reported by X.B.Yu et al requires more than 7 minutes for the hydrogen absorption of the hydrogen storage alloy Ti-V-Cr-Mn reported by 2015, such as 10 minutes (X.B.Yu,Z.X.Yang,S.L.Feng,Z.Wu,N.X Xu.Influence of Fe addition on hydrogen storage characteristics of Ti-V-based alloy[J].Int.J.Hydrogen Energy,2006,31:1176-1181.https://doi.org/10.1016/j.ijhydene.2005.09.008);J.B.Zhu, and the like, and (J.B.Zhu,L.Q.Ma,F.Liang,L.M.Wang,Effect of Sc substitution on hydrogen storage properties of Ti-V-Cr-Mn alloys[J].Int.J.Hydrogen Energy,2015,40:6860-6865.https://doi.org/10.1016/j.ijhydene.2015.03.149); has the authority of ZL 201910189586.3, chinese patent application name of high-hydrogen-release-efficiency multiphase hydrogen storage alloy and preparation method and application thereof, and solves the problems of the hydrogen absorption dynamics and the hydrogen release efficiency of the vanadium-based solid solution hydrogen storage alloy to a certain extent, but the hydrogen absorption capacity of the alloy is lower.

Therefore, how to realize a vanadium-titanium-based BCC structure solid solution hydrogen storage alloy with low cost and high capacity and rapid hydrogen absorption kinetics is a problem to be solved by researchers. The high-entropy alloy (High entropy alloys, at least five main elements, the atomic percentage of each element is 5% -35%) has been attracting more and more attention in the material science field due to unique physical and chemical properties. To date, most of the research on high-entropy alloys has focused on their potential application as structural materials. In fact, high entropy alloys may have great promise in functional materials, in addition to being structural materials. Compared with the traditional metal compound, the high entropy can promote the formation of a single-phase solid solution structure and has serious lattice deformation (strain). The lattice deformation forms more suitable reaction sites which may contribute to gas absorption, resulting in good performance.

Disclosure of Invention

The invention provides a BCC structure solid solution high-entropy hydrogen storage alloy with low cost, high capacity and ultra-fast hydrogen absorption kinetics.

The embodiment of the invention provides a hydrogen storage alloy which consists of five elements of vanadium, titanium, chromium, iron and manganese, wherein the chemical formula of the hydrogen storage alloy is expressed as V _aTi_bCr_cFe_dMn_e in terms of a molar ratio, wherein a is more than or equal to 34 and less than or equal to 36, b is more than or equal to 34 and less than or equal to 36,9 and less than or equal to c is more than or equal to 11, d is more than or equal to 9 and less than or equal to 11, e is more than or equal to 9 and less than or equal to 11, and a+b+c+d+e=100.

Preferably, the hydrogen storage alloy has a chemical formula composition of V ₃₅Ti₃₅Cr₁₀Fe₁₀Mn₁₀ in terms of a molar ratio.

It is preferable that the hydrogen absorbing alloy has a solid solution phase of a BCC structure, wherein the proportion of the solid solution phase of the BCC structure is 97% or more.

Preferably, the hydrogen absorbing capacity of the hydrogen absorbing alloy at room temperature is 3.27wt% or more.

Preferably, the time for the hydrogen absorbing alloy to reach 90% of the saturation amount at room temperature is 77 seconds or less.

The invention also provides a preparation method of the hydrogen storage alloy, which comprises the following steps:

s1, preparing materials according to the chemical formula, wherein the purity of the metal simple substance raw materials for preparing materials is over 99.5 percent;

s2, smelting the raw materials, wherein the smelting is performed in a protective atmosphere;

s3, naturally cooling along with the furnace body after smelting to obtain the alloy.

Preferably, the smelting is performed in a non-consumable vacuum arc furnace.

Preferably, the protective atmosphere comprises argon.

Preferably, the method is characterized in that in order to ensure the uniformity of the alloy, the alloy is subjected to overturn smelting for 3-10 times in the step S2.

The beneficial effects of the invention are as follows:

1) The low-cost high-capacity and ultra-fast hydrogen absorption high-entropy hydrogen storage alloy disclosed by the invention utilizes high entropy to promote the formation of a BCC structure solid solution single phase, and the crystal lattice has serious distortion, more proper reaction sites are generated, and the gas absorption is facilitated, so that the high-capacity hydrogen storage alloy has high capacity.

2) The low-cost high-capacity and ultra-fast hydrogen absorption high-entropy hydrogen storage alloy has larger atomic size difference, so that serious lattice distortion is generated, the alloy atoms are delayed in diffusion due to the serious lattice distortion, the growth of alloy crystal grains is inhibited, nano crystal grains are formed, the grain boundary density is greatly increased, more channels are provided for the diffusion of hydrogen atoms, and the kinetics performance of hydrogen absorption and desorption is greatly improved.

3) The low-cost high-capacity and ultra-fast hydrogen absorption high-entropy hydrogen storage alloy has low vanadium content, and low cost due to the addition of low-cost iron, manganese, foam titanium and the like, is easy to activate, has a simple production method, and is suitable for the aspects of hydrogen storage tanks, hydrogen purification and the like.

Drawings

The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are illustrative and should not be construed as limiting the invention in any way, in which:

FIG. 1 is an X-ray diffraction pattern of an example.

FIG. 2 is a graph of the hydrogen absorption kinetics of the example.

Fig. 3 is a PCT curve of the example.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.

Example 1

And (3) proportioning according to the weight percentage determined by the formula of the V ₃₄Ti₃₆Cr₁₀Fe₁₀Mn₁₀ alloy, wherein the metal simple substance raw materials used in the experiment are all more than 99.5%, and smelting in a non-consumable vacuum arc furnace under the protection of argon. In order to ensure the components to be uniform, the alloy ingot is turned over and smelted for 3 times, and is cooled to room temperature along with the furnace. Polishing and grinding the outer surface of an ingot, mechanically crushing, sieving with 200 meshes, weighing 5g of alloy powder for X-ray phase analysis, weighing 2g of alloy powder, loading into a stainless steel reaction vessel of a self-made Sieverts type PCT tester, completely activating, performing hydrogen absorption kinetics test at room temperature and performing PCT measurement within a hydrogen pressure range of 0.02-5MPa, and the data are shown in the following table 1.

TABLE 1 Hydrogen storage Properties of alloys

Note that C _abs -hydrogen uptake (wt.%), C _des -hydrogen release (wt.%), P _eq is plateau pressure (MPa).

The alloy has a solid solution phase with a BCC structure, the proportion of the BCC solid solution phase exceeds 97%, the alloy only needs 70 seconds to absorb hydrogen to reach 90% of the saturation amount under 295K, the alloy shows ultra-fast hydrogen absorption dynamic performance, and in addition, the data in table 1 show that the hydrogen absorption capacity of the alloy is as high as 3.30wt.%. Compared with similar solid solution alloy at home and abroad, the performance is obviously superior in hydrogen absorption capacity, hydrogen absorption dynamics performance and the like.

Example two

And (3) proportioning according to the weight percentage determined by the formula of the V ₃₅Ti₃₅Cr₁₀Fe₁₀Mn₁₀ alloy, wherein the metal simple substance raw materials used in the experiment are all more than 99.5%, and smelting in a non-consumable vacuum arc furnace under the protection of argon. In order to ensure the components to be uniform, the alloy ingot is turned over and smelted for 5 times, and is cooled to room temperature along with the furnace. Polishing and grinding the outer surface of an ingot, mechanically crushing, sieving with 200 meshes, weighing 5g of alloy powder for X-ray phase analysis, weighing 2g of alloy powder, loading into a stainless steel reaction vessel of a self-made Sieverts type PCT tester, completely activating, performing hydrogen absorption kinetics test at room temperature and performing PCT measurement within a hydrogen pressure range of 0.02-5MPa, and the data are shown in the following table 2.

TABLE 2 Hydrogen storage Properties of alloys

FIG. 1 is a phase analysis chart of an alloy, which can be seen to have a solid solution phase of BCC structure, and the ratio of the BCC solid solution phase exceeds 97%, FIG. 2 is a hydrogen absorption kinetic performance of the alloy at 295K, which can be seen to take 77 seconds only to reach 90% of the saturated amount at 295K, and shows an ultrafast hydrogen absorption kinetic performance, FIG. 3 is a PCT chart of the alloy, and in addition, the data in Table 2 show that the hydrogen absorption capacity of the alloy of the invention at 295K is as high as 3.27wt.%. Compared with similar solid solution alloy at home and abroad, the performance is obviously superior in hydrogen absorption capacity, hydrogen absorption dynamics performance and the like.

Example III

And (3) proportioning according to the weight percentage determined by the formula of the V ₃₅Ti₃₅Cr₉Fe₁₁Mn₁₀ alloy, wherein the metal simple substance raw materials used in the experiment are all more than 99.5%, and smelting in a non-consumable vacuum arc furnace under the protection of argon. In order to ensure the components to be uniform, the alloy ingot is turned over and smelted for 7 times, and is cooled to room temperature along with the furnace. Polishing and grinding the outer surface of an ingot, mechanically crushing, sieving with 200 meshes, weighing 5g of alloy powder for X-ray phase analysis, weighing 2g of alloy powder, loading into a stainless steel reaction vessel of a self-made Sieverts type PCT tester, completely activating, performing hydrogen absorption kinetics test at room temperature and performing PCT measurement within the hydrogen pressure range of 0.02-5MPa, and the data are shown in the following table 3.

TABLE 3 Hydrogen storage Properties of alloys

The alloy has a solid solution phase with a BCC structure, the proportion of the BCC solid solution phase exceeds 97%, the alloy only takes 73 seconds to reach 90% of the saturated quantity when absorbing hydrogen at 295K, the alloy shows ultra-fast hydrogen absorption dynamic performance, and in addition, the data in table 3 show that the hydrogen absorption capacity of the alloy of the invention at room temperature is as high as 3.35wt.%. Compared with similar solid solution alloy at home and abroad, the performance is obviously superior in hydrogen absorption capacity, hydrogen absorption dynamics performance and the like.

Example IV

And (3) proportioning according to the weight percentage determined by the formula of the V ₃₅Ti₃₅Cr₁₀Fe₉Mn₁₁ alloy, wherein the metal simple substance raw materials used in the experiment are all more than 99.5%, and smelting in a non-consumable vacuum arc furnace under the protection of argon. In order to ensure the components to be uniform, the alloy ingot is turned over and smelted for 10 times, and is cooled to room temperature along with the furnace. Polishing and grinding the outer surface of an ingot, mechanically crushing, sieving with 200 meshes, weighing 5g of alloy powder for X-ray phase analysis, weighing 2g of alloy powder, loading into a stainless steel reaction vessel of a self-made Sieverts type PCT tester, completely activating, performing hydrogen absorption kinetics test at room temperature and performing PCT measurement within a hydrogen pressure range of 0.02-5MPa, and the data are shown in the following table 4.

TABLE 4 Hydrogen storage Properties of alloys

The alloy has a solid solution phase with a BCC structure, the proportion of the BCC solid solution phase exceeds 97%, the alloy only takes 75 seconds to reach 90% of the saturated quantity when absorbing hydrogen at 295K, the alloy shows ultra-fast hydrogen absorption dynamic performance, and in addition, the data in table 4 show that the hydrogen absorption capacity of the alloy of the invention at room temperature is as high as 3.30wt.%. Compared with similar solid solution alloy at home and abroad, the performance is obviously superior in hydrogen absorption capacity, hydrogen absorption dynamics performance and the like.

The above-described embodiments illustrate only the principle of the invention and its efficacy, but are not intended to limit the invention, as various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the invention, which is defined in the appended claims.

Claims

1. A hydrogen storage alloy is characterized by comprising five elements of vanadium, titanium, chromium, iron and manganese, wherein the chemical formula of the hydrogen storage alloy is expressed as V _aTi_bCr_cFe_dMn_e in terms of a molar ratio, wherein a is more than or equal to 34 and less than or equal to 36, b is more than or equal to 34 and less than or equal to 36,9 and less than or equal to c is more than or equal to 11, d is more than or equal to 9 and less than or equal to 11, e is more than or equal to 9 and less than or equal to 11, and a+b+c+d+e=100.

2. The hydrogen occluding alloy as recited in claim 1, wherein the hydrogen occluding alloy has a chemical formula composition in terms of molar ratio V ₃₅Ti₃₅Cr₁₀Fe₁₀Mn₁₀.

3. The hydrogen storage alloy according to claim 1 or 2, wherein the hydrogen storage alloy has a solid solution phase of BCC structure, wherein the proportion of the solid solution phase of BCC structure is 97% or more.

4. The hydrogen absorbing alloy according to claim 1 or 2, wherein the hydrogen absorbing alloy has a hydrogen absorbing capacity of 3.27wt% or more at room temperature.

5. The hydrogen occluding alloy as recited in claim 1 or 2, wherein the hydrogen occluding alloy has a time to reach 90% of the saturation amount at room temperature of 77 seconds or less.

6. The method for producing a hydrogen occluding alloy as recited in any one of claims 1 to 5, wherein said method comprises the steps of:

7. The method according to claim 6, characterized in that the smelting is performed in a non-consumable vacuum arc furnace.

8. The method of any one of claims 6-7, wherein the protective atmosphere comprises argon.

9. The method according to any one of claims 6-7, characterized in that in order to ensure an even alloy, the smelting is reversed 3-10 times in step S2.