Regulation and control method giving consideration to hydrogen storage capacity and hydrogen absorption and desorption platform pressure of titanium-based hydrogen storage material

Abstract

The invention discloses a regulation and control method giving consideration to hydrogen storage capacity and hydrogen absorption and desorption plateau pressure of a titanium-based hydrogen storage material. Target metal in the titanium-based hydrogen storage material is partially or completely replaced with metal with smaller atomic radius and higher electronegativity. The problem that the hydrogen storage capacity and the hydrogen absorption and desorption platform pressure are difficult to synergistically improve by adjusting and controlling the size of a single hydrogen storage gap at present can be solved, synchronous improvement of the hydrogen storage capacity and the hydrogen absorption and desorption platform pressure of the titanium-based hydrogen storage material is facilitated, and the method has the advantages of being flexible to adjust and control and easy to apply on a large scale.

Description

Technical Field

[0001] The present invention relates to the field of hydrogen storage alloy materials, and particularly relates to a method for regulating the hydrogen storage capacity and the hydrogen absorption and desorption platform pressure of a titanium-based hydrogen storage material. Background Art

[0002] The large-scale application of hydrogen energy urgently requires the support of efficient and safe storage technologies. The titanium-based AB2-type C14 Laves phase hydrogen storage alloy has broad development prospects due to its unique structural and performance advantages. However, simultaneously achieving a high hydrogen storage capacity and a suitable hydrogen absorption and desorption platform pressure remains a key technical bottleneck in the practical application of this type of alloy. Alloying is an effective means to improve the comprehensive performance of hydrogen storage alloys. In the prior art, relevant research mostly regulates the hydrogen storage capacity and the hydrogen absorption and desorption platform pressure of hydrogen storage alloys through alloying.

[0003] For example, the patent specification with the publication number CN120026216A discloses a titanium-manganese-based hydrogen storage alloy, its preparation method and application. The composition of the titanium-manganese-based hydrogen storage alloy material is Ti a Zr b Mn 1.5mn X m Y n , where 0.6 ≤ a < 1, 0 < b ≤ 0.4, and a + b = 1, 0 < m ≤ 0.05, 0 < n ≤ 0.5, X includes at least one of Co, Cr, and Ni, and Y includes at least one of Fe and V. Although a high Zr content is beneficial to the improvement of the hydrogen storage capacity, it will have an adverse effect on the optimization of the hydrogen absorption and desorption platform pressure, and it is impossible to achieve the synergistic adaptation of the two.

[0004] The patent specification with the publication number CN120866708A discloses a long-life high-capacity titanium-based hydrogen storage alloy and its preparation method. The composition of the titanium-based hydrogen storage alloy material is Ti 0.85 Zr 0.15 Mn 1.05x Cr 0.85 (FeV) x , where 0 < x ≤ 0.1. Under the conditions of 25 °C and 3 - 4 MPa of H2, the maximum hydrogen absorption amount ≥ 1.8 wt.%, which improves the adaptability of the hydrogen storage capacity and the hydrogen absorption and desorption platform pressure to a certain extent. However, the relatively low hydrogen storage capacity still restricts the popularization and application of this series of alloys.

[0005] Furthermore, the patent specification with the publication number CN120210631A discloses a titanium-based hydrogen storage alloy material, its preparation method and application. The composition of the titanium-based hydrogen storage alloy material is Ti 0.890 Zr 0.110 Cr 0.900 Mn 0.800 Fe 0.175 (VFe)0.125 +x wt.%Ce, where x is 0~5. Although the higher Ti / Zr ratio provides a suitable hydrogen absorption and desorption plateau pressure, this series of alloys has a two-phase structure with the C14 Laves phase as the main phase and the CeO2 phase as the second phase. The CeO2 phase cannot provide effective hydrogen storage capacity, thus leading to a reduction in usable hydrogen storage density.

[0006] For thermodynamic modification of hydrogen storage alloys, substitution with elements with smaller atomic radii typically leads to a decrease in the thermodynamic stability of interstitial hydrogen atoms due to the reduced interstitial hydrogen interstic size, thereby increasing the hydrogen desorption plateau pressure of the alloy. This method is often used to control the hydrogen absorption and desorption plateau pressures, but the increase in absorption plateau pressure during this process negatively impacts the hydrogen storage capacity. While existing alloying techniques can increase the desorption plateau pressure by introducing elements with smaller atomic radii, reducing the geometry of the hydrogen absorption interstices, and decreasing the thermodynamic stability of interstitial hydrogen atoms, the simultaneously increased absorption plateau pressure reduces the hydrogen storage capacity under specific pressure conditions. Currently, no effective alloying strategies or solutions have been proposed for the simultaneous improvement of hydrogen storage capacity and absorption / desorption plateau pressures. Summary of the Invention

[0007] To address the aforementioned technical problems and shortcomings in this field, this invention provides a method for regulating both the hydrogen storage capacity and the hydrogen absorption / desorption plateau pressure of titanium-based hydrogen storage materials. This method solves the problem that current methods, which rely solely on adjusting the size of the hydrogen storage gap, cannot achieve synergistic improvement in both hydrogen storage capacity and hydrogen absorption / desorption plateau pressure. It helps to simultaneously improve the hydrogen storage capacity and hydrogen absorption / desorption plateau pressure of titanium-based hydrogen storage materials, and has the advantages of flexible regulation and ease of large-scale application.

[0008] In a first aspect, the present invention provides a method for controlling the hydrogen storage capacity and hydrogen absorption / desorption plateau pressure of titanium-based hydrogen storage materials, by partially or completely replacing the target metal in the titanium-based hydrogen storage material with a metal that has a smaller atomic radius and stronger electronegativity (stronger affinity for hydrogen atoms).

[0009] This invention proposes that, in the process of alloy composition design, substitution element screening, and substitution amount optimization, in addition to considering the regulatory effect of substitution elements on the interstitial size of hydrogen atoms, the affinity (electronegativity) between substitution elements and hydrogen atoms should be incorporated into the core evaluation index. Elements that have both the effect of reducing interstitial size and the effect of enhancing the hydrogen-metal atom bonding ability should be selected as substitution components. Through the dual regulation of hydrogen storage interstitial size and element hydrogen affinity, the synergistic improvement of hydrogen storage capacity and hydrogen absorption / desorption plateau pressure can be achieved.

[0010] In some preferred embodiments, the titanium-based hydrogen storage material is an AB2 type hydrogen storage alloy.

[0011] In some preferred embodiments, the AB2 type hydrogen storage alloy is a C14 Laves phase or a C15 Laves phase.

[0012] In some preferred embodiments, the titanium-based hydrogen storage material is a TiCr2-based alloy or a TiMn2-based alloy.

[0013] In some preferred embodiments, the titanium-based hydrogen storage material is a TiCr2-based alloy, the target metal includes Cr, and the metal with a smaller atomic radius and higher electronegativity includes Mn.

[0014] As a general inventive concept, in a second aspect, the present invention provides a titanium-based hydrogen storage material, wherein the compositional formula of the titanium-based hydrogen storage material, on an atomic basis, is Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ,in y =0~0.2.

[0015] In some embodiments, y =0.1.

[0016] In some embodiments, y =0.2, that is, the composition expression of the titanium-based hydrogen storage material is Ti 0.94 Zr 0.08 Mn 1.35 Cr 0.4 (VFe) 0.25 Its room temperature hydrogen storage capacity can reach 2.02 wt.%, and the room temperature hydrogen absorption and desorption platform pressures can reach 3.2 MPa and 1.3 MPa, respectively.

[0017] The titanium-based hydrogen storage material described in the second aspect has a room temperature hydrogen storage capacity of more than 2 wt.%.

[0018] Thirdly, the present invention provides the application of the titanium-based hydrogen storage material described in the second aspect in fuel cells.

[0019] While existing alloying control methods can increase the hydrogen absorption and desorption platform pressure by introducing elements with small atomic radii, reducing the geometric size of the hydrogen storage gap, and decreasing the thermodynamic stability of interstitial hydrogen atoms, the reduced hydrogen storage gap will decrease the number of hydrogen storage gaps that can accommodate hydrogen atoms, thus leading to a decrease in hydrogen storage capacity.

[0020] Compared with the prior art, the beneficial effects of this invention are as follows: This invention proposes that, in the process of alloy composition design, substitution element screening, and substitution amount optimization, in addition to considering the regulatory effect of substitution elements on the interstitial size of hydrogen atoms, the affinity between substitution elements and hydrogen atoms should be further incorporated into the core evaluation index. Elements that have both the effect of reducing interstitial size and the effect of enhancing the hydrogen-metal atom bonding ability are selected as substitution components, and the substitution ratio is reasonably controlled. Through the dual-effect regulation of hydrogen storage interstitial size and element hydrogen affinity, the hydrogen storage capacity and hydrogen absorption / desorption plateau pressure of titanium-based hydrogen storage alloys are finally improved synergistically. Attached Figure Description

[0021] Figure 1 For activated Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x X-ray diffraction (XRD) patterns of alloys with values ​​of 0, 0.05, 0.1, and 0.15.

[0022] Figure 2 For activated Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x =0, 0.05, 0.1, 0.15) Correlation between alloy cell volume and Zr content (bar chart).

[0023] Figure 3 For activated Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x Pressure-composition-isotherm (PCT) curves of alloys with values ​​of 0, 0.05, 0.1, and 0.15.

[0024] Figure 4 For activated Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x Line graph showing the correlation between the room temperature hydrogen absorption / desorption plateau pressure of alloys with values ​​of 0, 0.05, 0.1, and 0.15 and the Zr content.

[0025] Figure 5 For activated Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 (x A bar chart showing the correlation between room temperature hydrogen storage capacity and Zr content of alloys with values ​​of 0, 0.05, 0.1, and 0.15.

[0026] Figure 6 For activated Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y XRD patterns of alloys with the following composition: 0, 0.1, 0.2, 0.3.

[0027] Figure 7 For activated Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y =0, 0.1, 0.2, 0.3) Correlation bar chart of alloy cell volume and Mn content.

[0028] Figure 8 For activated Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y PCT curves of alloys with values ​​of 0, 0.1, 0.2, and 0.3.

[0029] Figure 9 For activated Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y Line graph showing the correlation between the room temperature hydrogen absorption / desorption plateau pressure of alloys with values ​​of 0, 0.1, 0.2, and 0.3 and the Mn content.

[0030] Figure 10 For activated Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y =0, 0.1, 0.2, 0.3) Correlation bar chart of room temperature hydrogen storage capacity of alloys with Mn content. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Operating methods not specifically specified in the following embodiments are generally performed under conventional conditions or as recommended by the manufacturer.

[0032] Example 1: To illustrate the significant impact of the choice of substitution element and the amount of substitution on hydrogen storage capacity and hydrogen adsorption / desorption plateau pressure, a Ti / Zr mixture was designed by varying the Ti / Zr ratio. 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x For alloys with values ​​of 0, 0.05, 0.1, and 0.15, the influence of replacing Ti atoms with Zr atoms (which have larger atomic radii and stronger hydrogen affinity) on the hydrogen storage capacity and hydrogen absorption / desorption plateau pressure of the alloys was investigated.

[0033] The alloy preparation process is as follows: (1) Weigh each metal raw material precisely according to the designed stoichiometric ratio and place them into the water-cooled copper crucible in order of melting point from high to low in order to reduce the risk of high melting point metals being difficult to melt or local overheating.

[0034] (2) Perform at least three evacuation-charging cycles on the alloy to fully remove residual impurity gases in the smelting environment, and then charge with 0.03-0.07 MPa of high-purity argon to establish and maintain a near-inert, low-oxygen protective atmosphere to prevent the alloy from being oxidized during the smelting process.

[0035] (3) During the smelting process, the heating power is precisely controlled by combining gradient heating and segmented cooling to make the metal melting and cooling process as uniform as possible. The single smelting time is about 4 minutes, thereby reducing the component segregation caused by excessive temperature gradient.

[0036] (4) Each alloy ingot needs to be turned over and remelted three times after the initial melting and forming to promote the full mixing of each element in the melt, thereby achieving compositional homogenization at both the macroscopic and microscopic scales.

[0037] All prepared alloy samples were stored in an argon-protected glove box. Activation was required before testing. Approximately 2 g of alloy sample was removed from the argon-protected glove box and placed in the reactor. After sealing the reactor, it was connected to a Sieverts hydrogen storage performance tester of known volume. The reactor valve was kept open, and the evacuation valve was opened to evacuate the hydrogen chamber and reactor. The heating program was set to heat the reactor to 100°C. After evacuation for 30 minutes, the evacuation valve was closed, and the inlet valve was opened to introduce hydrogen gas at 7–8 MPa into the hydrogen chamber and reactor. The inlet valve was then closed. Once the alloy underwent hydrogen absorption and reached saturation, the vent valve was opened to release the high-pressure hydrogen gas from the reactor. When the gas pressure inside the chamber dropped to approximately 1 MPa, the vent valve was closed, the evacuation valve was opened, and the heating program was activated to evacuate the hydrogen chamber again. This process was repeated three times, and the pressure readings during the activation and hydrogen absorption process were recorded in detail until the alloy sample was fully activated. The XRD pattern, PCT curve, and room temperature hydrogen storage capacity of the fully activated sample were tested (the room temperature mentioned in this invention is 20°C).

[0038] Figure 1 For Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x XRD patterns of alloys with values ​​of 0, 0.05, 0.1, and 0.15. Figure 2 According to Figure 1 Ti obtained through fine-tuning 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x The bar chart shows the correlation between the alloy cell volume (0, 0.05, 0.1, 0.15) and the Zr content. It can be seen that the alloy cell volume increases with increasing Zr content. Figure 3 For Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x PCT curves of alloys with values ​​of 0, 0.05, 0.1, and 0.15. Figure 4 According to Figure 3 Ti obtained by van der Hoff fitting 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( xLine graphs showing the correlation between the hydrogen absorption / desorption plateau pressure of alloys with Zr content (=0, 0.05, 0.1, 0.15) at room temperature and Zr content. It can be seen that the hydrogen absorption / desorption plateau pressure of the alloys decreases with increasing Zr content. Figure 5 For Ti 0.99-x Zr 0.03+x Mn 1.25 Cr 0.5 (VFe) 0.25 ( x The bar chart shows the correlation between the room-temperature hydrogen storage capacity of alloys with Zr content (0, 0.05, 0.1, 0.15). It can be seen that the room-temperature hydrogen storage capacity of the alloy increases with increasing Zr content. This experimental phenomenon can be explained, in part, by the difference in atomic radii between Ti (176 pm) and Zr (206 pm). After Zr partially replaces Ti, the larger Zr atoms participate in the formation of the hydrogen storage interstitial space of the alloy, thereby increasing the cell volume and the size of the hydrogen storage interstitial space. This leads to improved thermodynamic stability of interstitial hydrogen atoms and a reduction in the hydrogen absorption / desorption plateau pressure, thus increasing the hydrogen storage capacity under the same pressure conditions. Furthermore, from the perspective of elemental hydrogen affinity, the hydrogen affinity of metal atoms can be described by electronegativity, which describes the ability of an atom to gain electrons. In metal hydrides, hydrogen atoms are usually the electron donors. The stronger the ability of metal atoms to lose electrons (i.e., the weaker the electronegativity), the easier it is for the metal to act as an electron donor, supplying electrons to hydrogen atoms, thereby forming metal-hydrogen bonds. Based on the difference in electronegativity between Ti (1.54) and Zr (1.33), the partial substitution of Ti by Zr will introduce stronger Zr-H bonds, enhancing the bonding strength between metal atoms and interstitial hydrogen atoms, thereby increasing hydrogen storage capacity.

[0039] Example 2: While partial substitution of Ti with Zr can significantly improve the room-temperature hydrogen storage capacity of titanium-based hydrogen storage alloys, the significantly reduced hydrogen adsorption / desorption plateau pressure is unsuitable for practical fuel cell applications. To further illustrate the significant impact of the choice of substitution element and the substitution amount on hydrogen storage capacity and hydrogen adsorption / desorption plateau pressure, Zr was used in the substitution of Ti... 0.94 Zr 0.08 Mn 1.25 Cr 0.5 (VFe) 0.25 Based on this, Ti was designed by changing the Cr / Mn ratio. 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y =0, 0.1, 0.2, 0.3) alloy.

[0040] The alloy preparation process is as follows: (1) Weigh each metal raw material precisely according to the designed stoichiometric ratio and place them into the water-cooled copper crucible in order of melting point from high to low in order to reduce the risk of high melting point metals being difficult to melt or local overheating.

[0041] (2) Perform at least three evacuation-charging cycles on the alloy to fully remove residual impurity gases in the smelting environment, and then charge with 0.03-0.07 MPa of high-purity argon to establish and maintain a near-inert, low-oxygen protective atmosphere to prevent the alloy from being oxidized during the smelting process.

[0042] (3) During the smelting process, the heating power is precisely controlled by combining gradient heating and segmented cooling to make the metal melting and cooling process as uniform as possible. The single smelting time is about 4 minutes, thereby reducing the component segregation caused by excessive temperature gradient.

[0043] (4) Each alloy ingot needs to be turned over and remelted three times after the initial melting and forming to promote the full mixing of each element in the melt, thereby achieving compositional homogenization at both the macroscopic and microscopic scales.

[0044] All prepared alloy samples were stored in an argon-protected glove box. Activation was required before testing. Approximately 2 g of alloy sample was removed from the argon-protected glove box and placed in the reactor. After sealing the reactor, it was connected to a Sieverts hydrogen storage performance tester of known volume. The reactor valve was kept open, and the evacuation valve was opened to evacuate the hydrogen chamber and reactor. The heating program was set to heat the reactor to 100°C. After evacuation for 30 minutes, the evacuation valve was closed, and the inlet valve was opened to introduce hydrogen gas at 7–8 MPa into the hydrogen chamber and reactor. The inlet valve was then closed. Once the alloy underwent hydrogen absorption and reached saturation, the vent valve was opened to release the high-pressure hydrogen gas from the reactor. When the gas pressure inside the chamber dropped to approximately 1 MPa, the vent valve was closed, the evacuation valve was opened, and the heating program was activated to evacuate the hydrogen chamber again. This process was repeated three times, and the pressure readings during the activation and hydrogen absorption process were recorded in detail until the alloy sample was fully activated. The XRD pattern, PCT curve, and room temperature hydrogen storage capacity of the fully activated sample were tested (the room temperature mentioned in this invention is 20°C).

[0045] Figure 6 For Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y XRD patterns of alloys with the following composition: 0, 0.1, 0.2, 0.3. Figure 7 According to Figure 6 Ti obtained through fine-tuning0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y The bar chart shows the correlation between the alloy cell volume (0, 0.1, 0.2, 0.3) and the Mn content. It can be seen that the alloy cell volume decreases with increasing Mn content. Figure 8 For Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y PCT curves of alloys (0, 0.1, 0.2, 0.3). Figure 9 According to Figure 8 Ti obtained by van der Hoff fitting 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( y Line graph showing the correlation between the hydrogen absorption / desorption plateau pressure of the alloy at room temperature (0, 0.1, 0.2, 0.3) and the Mn content. It can be seen that the hydrogen absorption plateau pressure increases with increasing Mn content, while the hydrogen desorption plateau pressure does not change significantly with increasing Mn content.

[0046] The above experimental phenomena can be explained, in part, by the difference in atomic radii between Mn (161 pm) and Cr (166 pm). As the Mn / Cr ratio increases, the positions previously occupied by Cr atoms are occupied by Mn atoms. The smaller-radius Mn atoms participate more in forming the hydrogen storage interstitial spaces of the alloy, thus reducing the unit cell volume and the size of the hydrogen storage interstitial spaces. This leads to a decrease in the thermodynamic stability of the interstitial hydrogen atoms and an increase in the hydrogen absorption plateau pressure. From this perspective, under the same pressure conditions, the hydrogen storage capacity should decrease. However… Figure 10 For Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ( yThe bar chart shows the correlation between the room-temperature hydrogen storage capacity of the alloy (0, 0.1, 0.2, 0.3) and the Mn content. It can be seen that within the Mn content range of 1.15–1.35%, the room-temperature hydrogen storage capacity of the alloy does not change significantly with increasing Mn content. However, when the Mn content exceeds 1.35%, an increase in Mn content leads to a significant decrease in the room-temperature hydrogen storage capacity. This phenomenon indicates that the change in hydrogen storage capacity cannot be explained solely by the interstitial size effect. Normally, a decrease in unit cell volume limits the number of interstitial spaces that hydrogen atoms can occupy, thus hindering the improvement of hydrogen storage capacity; however, in this system, the room-temperature hydrogen storage capacity remains essentially stable with increasing Mn content. The reason lies in the fact that Mn exhibits a stronger affinity for hydrogen than Cr. The hydrogen affinity of metal atoms can be described by electronegativity, which describes the ability of an atom to gain electrons. In metal hydrides, hydrogen atoms are usually the electron donors. The stronger the ability of metal atoms to lose electrons, i.e., the weaker the electronegativity, the easier it is for the metal to act as an electron donor, supplying electrons to hydrogen atoms, thereby forming metal-hydrogen bonds. Based on the difference in electronegativity between Mn (1.55) and Cr (1.66), as the Mn / Cr ratio increases, the positions of the original Cr atoms are occupied by Mn atoms, introducing stronger Mn-H bonds, enhancing the bonding strength between metal atoms and interstitial hydrogen atoms, partially compensating for the adverse effects of lattice shrinkage on hydrogen storage capacity, thus enabling the alloy to maintain a relatively stable saturated hydrogen storage capacity in the high Mn content range. Among them, the optimized Ti 0.94 Zr 0.08 Mn 1.35 Cr 0.4 (VFe) 0.25 The alloy can achieve a room temperature hydrogen storage capacity of over 2 wt.%, while the hydrogen absorption and desorption plateau pressures reach 3.2 MPa and 1.3 MPa, respectively.

[0047] As can be seen, in the process of alloy composition design, screening of substitution elements and optimization of substitution amount, this invention, in addition to considering the regulatory effect of substitution elements on the size of hydrogen storage gaps where hydrogen atoms are located, further incorporates the affinity between substitution elements and hydrogen atoms into the core evaluation index, selects elements that have both the effect of reducing gap size and the effect of enhancing the binding ability of hydrogen-metal atoms as substitution components, and finally achieves a synergistic improvement in hydrogen storage capacity and hydrogen absorption and desorption platform pressure.

[0048] Furthermore, it should be understood that after reading the above description of the present invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A method for regulating the hydrogen storage capacity and hydrogen absorption / desorption plateau pressure of titanium-based hydrogen storage materials, characterized in that, The target metal in the titanium-based hydrogen storage material is partially or completely replaced by a metal with a smaller atomic radius and higher electronegativity.

2. The control method according to claim 1, characterized in that, The titanium-based hydrogen storage material is an AB2 type hydrogen storage alloy.

3. The control method according to claim 2, characterized in that, The AB2 type hydrogen storage alloy is a C14 Laves phase or a C15 Laves phase.

4. The control method according to claim 2 or 3, characterized in that, The titanium-based hydrogen storage material is a TiCr2-based alloy or a TiMn2-based alloy.

5. The control method according to claim 4, characterized in that, The titanium-based hydrogen storage material is a TiCr2-based alloy, the target metal includes Cr, and the metal with smaller atomic radius and stronger electronegativity includes Mn.

6. A titanium-based hydrogen storage material, characterized in that, The compositional formula of the titanium-based hydrogen storage material, based on atomic ratio, is Ti 0.94 Zr 0.08 Mn 1.15+y Cr 0.6-y (VFe) 0.25 ,in y =0~0.

2.

7. The titanium-based hydrogen storage material according to claim 6, characterized in that, y =0.1。 8. The titanium-based hydrogen storage material according to claim 6 or 7 is used in fuel cells.

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