CN-121976108-A - Easy-to-activate TiFe-based hydrogen storage alloy and preparation method thereof

Abstract

The invention belongs to the technical field of solid hydrogen storage, and in particular relates to an easy-to-activate TiFe-based hydrogen storage alloy and a preparation method thereof, wherein the hydrogen storage alloy comprises the following specific components X is any one of 1 and 1.05, and y is any one of 0, 0.05 and 0.1. According to the invention, the alloy components are optimized through a strategy of nonstoichiometric ratio regulation and multi-element alloying, excessive Ti, transition group elements Mn, cr, zr and rare earth elements Ce are added into an AB type TiFe alloy matrix, and a plurality of second phases such as a Zr-rich TiFe phase, a Ce phase and Ti are successfully introduced, so that the activation performance of the TiFe-based alloy is remarkably improved. The hydrogen storage alloy is stable in storage under the conventional environment, does not need vacuum packaging and low-temperature storage, greatly reduces storage and transportation cost and use threshold, and has excellent industrial application prospect.

Inventors

• LIU XINYE
• XU JUNRUI
• LIU JINBO
• DING YUAN
• ZHAO ZHIHONG
• DOU ZHIWEI

Assignees

• 内蒙古工业大学

Dates

Publication Date

20260505

Application Date

20260409

Claims (10)

1. 1. An easy-to-activate TiFe-based hydrogen storage alloy is characterized in that the specific composition of the hydrogen storage alloy is that X is any one of 1 and 1.05, and y is any one of 0, 0.05 and 0.1.
2. 2. The readily activatable TiFe-based hydrogen storage alloy according to claim 1, wherein the hydrogen storage alloy comprises a multi-phase structure comprising a primary phase of TiFe and a secondary phase comprising a Ce phase, a Ti phase, a Zr-rich TiFe phase.
3. 3. The activatable TiFe-based hydrogen occluding alloy as recited in claim 2, wherein the second phase comprises 5 to 10% by volume.
4. 4. The easy-to-activate TiFe-based hydrogen storage alloy according to claim 1, wherein Ce element of the hydrogen storage alloy is not solid-dissolved in a matrix and shows a remarkable segregation behavior, zr element and Ti element have remarkable segregation effects, and Fe, cr, mn elements are uniformly distributed.
5. 5. A method for preparing the easy-to-activate TiFe-based hydrogen storage alloy according to any one of claims 1 to 4, comprising the following steps: S1, calculating the proportioning quantity of each element according to the chemical formula composition of the hydrogen storage alloy, and presetting the burning loss quantity of each element according to the smelting burning loss characteristics of Ti, fe, mn, ce, zr, cr; s2, placing the weighed raw materials into a water-cooled copper crucible, vacuumizing, filling inert gas for gas washing, repeating the gas washing for a plurality of times, smelting after gas washing, starting electromagnetic stirring after the raw materials are completely melted, cooling until the materials are solidified after the stirring is completed, turning over the materials to be melted again after solidification, and repeating for a plurality of times to obtain alloy cast ingots; s3, polishing the alloy ingot, mechanically crushing and sieving the polished alloy ingot to obtain hydrogen storage alloy powder.
6. 6. The method for preparing an easily activated TiFe-based hydrogen storage alloy according to claim 5, wherein in the step S1, the burning loss amount of Ti and Fe is 1-2% of the added mass of each element, and the burning loss amount of Mn, ce, zr, cr is 5-10% of the added mass of each element.
7. 7. The method for preparing an easily activated TiFe-based hydrogen storage alloy according to claim 5, wherein in the step S2, the raw material is divided into a bottom layer, a middle layer and a top layer after being placed in a water-cooled copper crucible, wherein the bottom layer comprises Fe blocks and Cr blocks, the middle layer comprises Ti particles and Zr particles, and the top layer comprises Mn sheets and Ce blocks.
8. 8. The method for preparing the easy-to-activate TiFe-based hydrogen storage alloy according to claim 7, wherein the top Mn sheets and Ce blocks are placed at the edge of the top layer to be in a hollow state.
9. 9. The method for producing an easily activatable TiFe-based hydrogen occluding alloy as recited in claim 5, wherein in step S2, the absolute pressure of the vacuum is The inert gas is filled to the gauge pressure of-0.05 MPa, and the inert gas is filled to the gauge pressure of 0.04-0.05 MPa in the last gas washing.
10. 10. The method for preparing an easily activated TiFe-based hydrogen storage alloy according to claim 5, wherein in the step S2, the smelting current is 160-180A, the electromagnetic stirring time is 30-60S, and the remelting times are 4 times.

Description

Easy-to-activate TiFe-based hydrogen storage alloy and preparation method thereof Technical Field The invention belongs to the technical field of solid hydrogen storage, and particularly relates to an easy-to-activate TiFe-based hydrogen storage alloy and a preparation method thereof. Background The hydrogen energy is strategic secondary energy for realizing the 'double carbon' target and guaranteeing the national energy safety, and has high cost in storage and transportation links and high safety management and control difficulty, and becomes a core bottleneck for restricting the commercialization of the hydrogen energy full-industry chain. The TiFe-based hydrogen storage alloy is taken as a typical AB-type hydrogen storage alloy, and is one of solid hydrogen storage materials with the most industrialization prospect in the field of fixed hydrogen storage systems by virtue of the core advantages of low raw material cost, high volume hydrogen storage density and capability of realizing reversible hydrogen absorption and desorption at room temperature. The pure TiFe alloy has two inherent defects that are difficult to break through, and the large-scale popularization and application of the pure TiFe alloy are directly restricted. The method has the advantages that firstly, the activation condition is extremely harsh, a compact passivation layer is extremely easy to form on the surface of the alloy, the compact passivation layer is difficult to effectively react with hydrogen in a conventional environment, the activation can be completed only through repeated hydrogen absorption and desorption cycles in a high-temperature and high-pressure hydrogen environment with the temperature of more than 400 ℃, the core requirements of low cost and easy operation in commercial application cannot be met, secondly, the impurity poisoning resistance is extremely poor, and trace hydrogen is prevented、Impurities such as CO and the like are highly sensitive, and the solid hydrogen storage material is extremely easy to generate, attenuate and even completely deactivate in a low-purity hydrogen environment, so that the threshold and the use cost of the solid hydrogen storage material are greatly improved. In the existing modification means of TiFe-based hydrogen storage alloy, elements replace short plates with high cost and poor mass production performance due to avoiding processes such as mechanical alloying, surface modification and the like, and become the modification technical scheme with the most industrialized feasibility in the industry. At present, although the transition element and the rare earth element are cooperated to replace the modified TiFe alloy to realize the rapid activation at room temperature and even no pretreatment for absorbing hydrogen, the existing modified alloy can only maintain the activation performance under the severe conditions of fresh preparation, whole vacuum or inert atmosphere protection, and the surface oxidation deactivation can rapidly occur in the processes of storage, transportation, filling and service of the alloy finished product in the normal-pressure air environment, so that the room temperature activation and reversible hydrogen absorption and release capacity are lost, and the core requirements of large-scale industrial production and engineering application cannot be met all the time. Disclosure of Invention The invention aims to solve the technical problem of providing an easy-to-activate TiFe-based hydrogen storage alloy and a preparation method thereof, the invention optimizes alloy components through a strategy of nonstoichiometric ratio regulation and multi-element alloying, excessive Ti, transition group elements Mn, cr, zr and rare earth element Ce are added into the AB type TiFe alloy matrix, and various second phases such as a Zr-rich TiFe phase, a Ce phase and Ti are successfully introduced, so that the activation performance of the TiFe-based alloy is remarkably improved. The hydrogen storage alloy is stable in storage under the conventional environment, does not need vacuum packaging and low-temperature storage, greatly reduces storage and transportation cost and use threshold, and has excellent industrial application prospect. The technical scheme adopted by the invention for solving the problems is as follows: an easy-to-activate TiFe-based hydrogen storage alloy comprises the following specific components X is any one of 1 and 1.05, and y is any one of 0, 0.05 and 0.1. According to the technical scheme, the atomic metering ratio of each element is determined according to the following steps that a hydrogen storage core of the TiFe-based hydrogen storage alloy is a TiFe intermetallic compound with a CsCl type structure, and the TiFe-based hydrogen storage alloy belongs to a typical AB-type hydrogen storage alloy. Cr and Mn are Fe (B) synergistic substitution elements, the functions of the Cr and Mn are highly complementary, and the directional and accurate regu