MATERIALS CHEMISTRY AND PHYSICS
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2024
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IF 4.3
Hai-Wen Li,Xi Wang,Liqing He,Jing Huang,Yongtao Li,Wanggang Fang,Tengfei Cheng,Xiao Li,Xinghai Ren,Xiaoliang Liu,Defu Nie,Huai-Jun Lin
TiMn-based AB 2 -type hydrogen storage alloy with low cost, relatively suitable platform pressure, and high hydrogen storage capacity, stands out as one of the most promising candidates for practical applications in hydrogen storage. However, the TiMn-based alloy gradually losses activity, especially during prolonged exposure to air, posing challenges for activation and greatly increasing the operation cost in large-scale application. The LaNi 5 alloy exhibits excellent initial activation performance, making it an ideal additive to enhance the initial reaction kinetics of TiMn-based AB 2 -type alloy. Nevertheless, the introduction of LaNi 5 tends to reduce the hydrogen storage capacity of the mother alloy. Vanadium (V) possesses a relatively high hydrogen storage capacity (3.8 wt.%), and its addition can enhance the hydrogen storage capacity of the mother alloy. In this study, we employ a co-doping strategy, using 5 wt.% of LaNi 5 and 5 wt.% of V, to activate an inactive TiMn-based AB 2 -type alloy (placed for 1 year in air). This approach not only enhances the initial reactivity of the TiMn-based mother alloy but also restores its high-capacity performance. At 303 K and 6 MPa H 2 pressure, the co-doping alloy (90 wt.% TiMn-based alloy - 5 wt.% LaNi 5 - 5 wt.% V) demonstrates a substantial increase in initial hydrogen absorption rate, achieving a hydrogen absorption capacity of 1.61 wt.% in 6 min. The maximum hydrogen absorption capacity reaches 2.00 wt.% in 90 min. After 5 and 20 cycles, it maintains a reversible capacity of 1.55 and 1.45 wt.%, respectively. The outstanding hydrogen storage performance is attributed to the formation of multiphase alloys, as evidenced by X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) measurements. The reaction enthalpy (Δ H ) of the co-doping alloy is calculated as 34.1 kJ/(mol H 2 ), a value suitable for operation at room temperature. This work supplies an efficient strategy for the activation of long-time placed inactive hydrogen storage alloys and the enhancement of their hydrogen storage performance, and avoids the waste of raw materials due to inactivation in air. The achievements shed lights on the regeneration of inactive alloys and the cost control in the case of large-scale application of solid hydrogen storage alloys.
研究领域:
材料科学
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能源存储
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DOI
高影响因子
CATALYSIS TODAY
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2017
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IF 4.636
Tianxin Li,Qian Li,Hongyu Long,Kuo-Chih Chou,Qun Luo
A modified Chou model with parameters of temperature ( T ), initial hydrogen pressure ( P 0 ), enthalpy change (Δ H ) and entropy change (Δ S ) is proposed in consideration of thermodynamic driving force. The meaningful activation energy E v can be calculated for the negative temperature dependence of hydriding reaction in hydrogen storage materials. This model is verified by the hydriding/dehydriding experimental data of (LaNi 5 ) 1− x Mg x ( x = 0, 0.018, 0.041, 0.063). The calculated results indicate that the hydriding kinetics of (LaNi 5 ) 1− x Mg x alloys are controlled by diffusion of hydrogen atom in hydride. The addition of small amount of magnesium improves the kinetic performance of LaNi 5 slightly. Furthermore, the modified Chou model was compared with the previous model that successfully explain the negative temperature depending hydrogenation reaction of Mg-based alloys. The fitting results show that the modified Chou model can describe the hydrogen absorption kinetic mechanism of negative temperature dependent materials more accurately.
研究领域:
材料科学
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能源化学
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物理化学
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合金设计
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储氢技术
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DOI
高影响因子
RARE METALS
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2025
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IF 11
Zheng Hao-Yuan,Jin Chen,Che Hang,Lee Chia-Tse,Liu Guang,Wang Li,Zhao Yu-Yuan,Liu Hai-Zhen,Wang Xin-Hua,Yu Yi-Feng,Yan Mi
The Li–Mg–N–H (Mg(NH 2 ) 2 –2LiH) system, as a high-capacity Mg-based metal hydrogen storage material (5.6 wt%), has broad prospects for in vehicle hydrogen storage applications, but it still has high hydrogen ab/desorption barriers. To improve its hydrogen storage performance, a nanohydrogen storage alloy was innovatively combined with Mg(NH 2 ) 2 –2LiH, AB5 type nanohydrogen storage alloy LaNi 5 was prepared by co-precipitation method. Nano LaNi 5 and single-walled carbon nanotubes (SWCNTs) were co-doped into the Mg(NH 2 ) 2 –2LiH system at a ratio of 10 wt% and 2 wt%, significantly enhancing the hydrogen storage performance of Mg(NH 2 ) 2 –2LiH. The initial hydrogen ab/desorption temperatures of the co-doped system decreased from 110/130 °C to 45/85 °C. The release of by-product ammonia is significantly inhibited. 4.73 wt% H 2 can be ab/desorption in 150 min at 180/170 °C. Cycle tests show that the co-doped system can still maintain a hydrogen storage capacity of 4.75 wt% after ten hydrogen release cycles. Mechanism and density functional theory study have shown that during the hydrogen release process, partially hydrogenated LaNi 5 weakens the chemical bonding in Mg(NH 2 ) 2 , promoted the dissociation of hydrogen from the Mg(NH 2 ) 2 –2LiH system, while playing a dual role of "hydrogen overflow" and "hydrogen pump". SWCNTs act as auxiliary agents, helping to refine particle size and increase thermal conductivity. The synergistic effect of the two optimizes the comprehensive hydrogen storage performance of Mg(NH 2 ) 2 –2LiH. This study provides a new research method for improving the comprehensive hydrogen storage performance of Mg-based metal hydrogen storage materials using rare earth element catalysts. Graphical abstract
研究领域:
材料科学
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物理化学
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纳米催化
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能源存储
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计算材料学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Hao Shang,Hang Shi,Haoliang Yu,Xiaohong Hu,Yan Xia
To develop high-performance non-precious metal hydrogen evolution reaction HER catalysts for anion exchange membrane water electrolysis (AEMWE) and address the issue of the rate of Volmer step in HER being limited by H 2 O dissociation in alkaline media, we propose a strategy where LaNi 5 alloy is used as a co-catalyst for the adsorption and activation of H*, thereby accelerating the rate of the HER. We find that LaNi 5 has a significant HER synergistic effect with MoS 2 . The overpotential at 10 mA·cm −1 for HER catalyzed by the LaNi 5 -MoS 2 composite catalyst is only 143 mV in 1.0 M KOH solution, and the AEMWE using LaNi 5 -MoS 2 as cathode catalyst reaches 1.966 V at 1.0 A·cm⁻² and shows a low degradation. Mechanism studies suggest that LaNi 5 plays the role of adsorbing and activating H*, and the enriched H* from LaNi 5 overflows to MoS 2 , which has good H 2 desorption sites, resulting in improved HER kinetics of LaNi 5 -MoS 2 .
研究领域:
材料科学
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电化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2026
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IF 8.3
Jing Pan,Yongde Yan,Yanghai Zheng,Shengrong Guo,Xuepeng Wang,Sihao Wang,Zhiguang Du,Kaijie Wang,Yun Xue,Kai Zhu
A method for the preparation of LaNi 5 alloy by molten salt co-reduction is reported. The electrochemical co-reduction process of La(III) and Ni(II) as well as the reaction process of intermetallic compounds formation were investigated. It was confirmed that the diffusion coefficient of La(III) in LiF–CaF 2 molten salt is 4.684–8.098 × 10 −5 cm 2 s −1 at temperatures of 1113–1183 K. And the reaction activation energy was obtained to be 78.86 kJ mol −1 . And, the exchange current densities of La(III)/La(0) were determined by the Tafel (0.149–0.251 A cm −2 ) and linear polarization (0.143–0.204 A cm −2 ) methods. Furthermore, five different La–Ni intermetallic compounds were detected by studying the co-reduction reaction of La(III) and Ni(II) ions. Meanwhile, the formation potentials of La–Ni intermetallic compounds were defined by various electrochemical tests. In addition, the LaNi 5 alloy was obtained via potentiostatic electrolysis according to the electrochemical results. This study provides new insights into the electrochemistry of the LiF–CaF 2 –LaF 3 –NiF 2 molten salt and enhances the understanding of the molten salt electrolytic preparation of La–Ni alloys from co-reduction.
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）