MATERIALS CHARACTERIZATION
·
2023
·
IF 4.7
Jiwei Yao,Hui Yong,Yang Zhao,Chengyan Sun,Xianliu Xu,Baosheng Liu,Dongliang Zhao,Jifan Hu,Yanghuan Zhang
The Mg 90 Ce 5 Y 5 + x wt% ZnF 2 ( x = 3, 6, 10, 15) composites were prepared by mechanical ball-milling. The effects of ZnF 2 contents on the hydrogen absorption and desorption properties of Mg 90 Ce 5 Y 5 alloy were investigated by XRD , ICP-OES, TEM, PCT and DSC . The excellent hydriding-dehydriding characteristics of the samples after activation were attributed to the catalytic effect of the MgF 2 and MgZn 2 phases introduced in situ by the addition of ZnF 2 . The Mg 90 Ce 5 Y 5 + 6 wt% ZnF 2 composites exhibit the fastest hydrogen adsorption/desorption kinetics and lower decomposition temperatures. At 360 °C, 4.12 wt% H 2 can be absorbed within 180 s, and completely dehydrogenated within 740 s. In addition, the activation energy of dehydrogenation is reduced to 89.5 kJ/ mol, the optimal dehydrogenation temperature is reduced to 318 °C. It is due to the generation of in situ catalysts that weaken the Mg H bond energy, refine the grain sizes , expand specific surface area and increase hydrogen diffusion paths. However, the improvement of the thermodynamics of the composites is limited, the enthalpy is 75.9 kJ/mol H 2 .
研究领域:
材料科学
·
能源储存
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Han Yu,Ying Cheng,Yaokun Fu,Lu Zhang,Sanyang Guo,Yuan Li,Wei Zhang,Shumin Han
Carbon-based materials have been proposed as an ideal medium to reduce the reaction energy barriers and improve the (de)hydrogenation kinetics of magnesium-based hydrogen storage material (MgH 2 ) in term of their excellent dispersion. However, tedious preparation process and uneven distribution of carbon restrict the application. Therefore, in this paper, we cover MgH 2 by in-situ formed amorphous carbon via a facile approach of co-sintering Mg with fluorene followed by hydriding combustion and ball milling processes, named as MgH 2 -carbonization product of fluorene (MgH 2 -CPF). As a result, the MgH 2 -CPF composite prepared at 823 K initially dehydrogenates at 557 K, 94 K lower than the as-milled MgH 2 (651 K). Meanwhile, the composite can release 5.67 wt% H 2 within 1000 s at 623 K. Even at a lower temperature of 423 K, the MgH 2 -CPF composite still reabsorbs 5.62 wt% H 2 within 3600 s, while the as-milled Mg can hardly absorb hydrogen under a same condition. Furthermore, by addition of CPF, the apparent activation energy of the system is decreased from 161.2 kJ/mol to 87.2 kJ/mol. Our finding suggests that the carbon layer can keep the MgH 2 from aggregation, promote hydrogen transport and improve the efficiency of hydrogen absorption and desorption.
研究领域:
材料科学
·
氢储存
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2024
·
IF 5.8
Lei Sun,Rong Sun,Jianjun Liu,Mengzhou Zhu,Xiaoqin Zhang,Dongliang Guo,Kangyong Yin,Zhiyun Zhuang,Xueqiong Zhu,Peng Xiao
MgH2 used in solid-state hydrogen storage still suffers from high thermal stability and slow hydrogen absorption–desorption kinetics. Here, we report a hybrid of MgH2–Ti3C2/graphene prepared through a facile wet chemical method followed by a ball-milling method. It was confirmed that the coupling of Ti3C2 and graphene possesses a synergistic effect on the hydrogen desorption and absorption reactions of MgH2/Mg. The initial temperature of MgH2–Ti3C2/graphene to desorb hydrogen was reduced to 169 °C significantly and it could desorb 6.8 wt% H2 within 6 min at a constant temperature of 300 °C. Moreover, the desorbed sample could start to absorb hydrogen at room temperature and achieve a capacity of 6.0 wt% when the temperature was gradually increased to 350 °C. These results are far superior to pristine MgH2, disclosing that the addition of two-dimensional Ti3C2/graphene is an efficient strategy to boost the hydrogen storage performance of MgH2.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Magnesium and Alloys
·
2021
·
IF 10.088
Bogu Liu,Bao Zhang,Haixiang Huang,Xiaohong Chen,Yujie Lv,Zhongyu Li,Jianguang Yuan,Ying Wu
Ni and carbon materials exhibit remarkable catalysis for the hydriding reaction of Mg. But the underlying mechanism of Ni/C hybrid catalysis is still unclear. In this work, density functional theory (DFT) calculation is applied to investigate the effect of Ni/C co-incorporation on the hydriding reaction of Mg crystal. The morphology and crystal structure of the Ni/C co-incorporated Mg sample show that the co-incorporated structure is credible. The transition state searching calculation suggests that both the incorporations of Ni and C are beneficial for the H 2 dissociation. But Ni atom has a dramatic improvement for H 2 dissociation and makes the H diffusion become limiting step of the hyriding reaction. The Ni d z 2 orbit and H s orbit accept the electrons and combine together compactly, while the Ni d xy orbit is half-occupied. The catalytic effect of Ni on H 2 dissociation can be ascribed to the bridging effect of Ni d xy orbit. The incorporation of C can weaken the over-strong interaction between Ni and H which hindered the H diffusion on Mg(0001). The Ni/C co-incorporated Mg(0001) shows the best performance during hyriding reaction compared with the clean and single incorporated Mg(0001).
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Chenjie Dong,Guansheng Li,Jiajing Zhu,Jie Cui,Liangjun Huang,Hui Wang
MgH 2 is a high-density hydrogen storage material but requires an efficient catalyst to improve its poor kinetics and reduce high operating temperature. TiO 2 is a widely used photocatalyst for water splitting and hydrogen production, and has also demonstrated catalytic ability in the gas-solid reaction of MgH 2 . In this study, we synthesize the Ni-doped TiO 2 nanoparticles, which significantly reduce the hydrogen absorption temperature down to subzero temperatures. The milled composite of MgH 2 with 10 wt% Ti(5Ni)O 2 can absorb 5.25 wt% H 2 within 30 s at 25 °C, 4.30 wt% H 2 within 50 s at 0 °C, and 3.94 wt% H 2 within 50 s even at a low temperature of −30 °C. This composite can release 6.04 wt% of hydrogen in 3 min at 250 °C, and the dehydrogenation activation energy is reduced to 74.57±1.36 kJ/mol, a notable reduction in comparison to that observed in pure MgH 2 . This study demonstrates the potential of the modified TiO 2 as an important kind of catalyst for solid-state hydrogen storage materials.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2023
·
IF 9.4
Hui Yong,Yiwan Chen,Yanquan Ji,Shuai Wang,Jiangwei Ma,Baosheng Liu,Jifan Hu,Yanghuan Zhang
Solid-state magnesium-based hydrogen storage encounters challenges associated with sluggish hydrogen absorption and desorption kinetics. The incorporation of catalysts is considered a promising means to improve the hydrogen absorption and desorption kinetics of these alloys. In this experiment, we prepared the Mg 80 Ni 15 Y 5 alloy via vacuum melting and incorporated TiF 3 in varying weight percentages of 1, 3, 5, and 7 wt% through ball milling . The phase composition and microstructure of the samples were analyzed and measured using X-ray diffraction meter (XRD), Transmission Electron Microscope (TEM), Selected Area Electron Diffraction (SAED), and Scanning Electron Microscope (SEM) techniques. The results revealed that the TiF 3 introduced two catalytically phases, MgF and TiF 2 . And TiF 2 transforms into TiH 2 after hydrogen absorption, which covers the surface of MgH 2 and prolongs the nucleation time of MgH 2 .Furthermore, the addition of TiF 3 made the surface of alloy markedly coarser and more irregular and few cracks, providing channels for hydrogen diffusion. This behavior optimized the kinetic performance of the alloy. It was observed that the samples containing 7 wt%TiF 3 achieved 99.2 % hydrogen saturation even in low-temperature. It's worth mentioning that the addition of 7 wt% TiF 3 to the Mg 80 Ni 15 Y 5 alloy significantly reduced the dehydrogenation activation energy to 58.5 kJ/mol, as opposed to pure magnesium with an activation energy of 158.2 kJ/mol. This substantial reduction has effectively accelerated the hydrogen absorption and desorption rates of the alloy. However, it had only a negligible impact on the thermodynamic properties of the sample with 7 wt%TiF 3 .
研究领域:
材料科学
·
能源储存
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2017
·
IF 3.359
Guangfei Qu,Qian Zhao,Ronglong Jian,Junya Wang,Dianxin Liu,Ping Ning
Beginning with the formation of the ionic liquid/water two-liquid phase catalytic system for absorption of PH 3 , we designed and synthesized Cu + -[Bmim]PF 6 , which has a hydrophobic property, and later formed a two-liquid phase system with Cu + -[Bmim]PF 6 and water, which has high PH 3 absorption efficiency, and an effective separation of the product and the catalyst was achieved. The effects of temperature and O 2 concentration on phosphine absorption, and the distribution of catalytic components and products in the ionic liquid/aqueous two-phase system were studied. Moreover, the mechanism of Cu + -ILs/water two-liquid phase catalytic oxidation of phosphine was discussed based on results from the analysis of FT-IR and ion chromatography . The results demonstrated that the optimum oxygen content in the reaction was 3%, and the optimum reaction temperature was 45 °C. Cu + -ILs/water two-liquid phase system has a high absorption efficiency for PH 3 , the absorption process is liquid phase catalytic oxidation and the product is H 3 PO 4 . The two-liquid phase system is semi-intelligent. The system can achieve high performance liquid phase catalytic oxidation of PH 3 , as well as automatic separation of H 3 PO 4 .
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Hui Liang,Jing Li,Xinhui Shen,Benliang Cao,Junxiang Zhu,Baozhang Geng,Sihang Zhu,Wenjiang Li
Amorphous catalysts have a large number of catalytic active sites. Here, we report a magnesium composite trace lanthanum catalyst (La@Mg), in which La and Mg layers form amorphous Mg–La compound on the surface of layered Mg. The test shows this La@Mg has hydrogen storage capacity of about 7.6 wt% and hydrogen desorption of 7.2 wt%, higher than that of crystalline La@Mg and sole Mg, rapid absorption/desorption kinetic and stable reversible absorption/desorption cycles. La@Mg exhibits an optimistic hydrogen storage performance than Mg-based materials previously reported in the literature. Combined with theoretical calculations, it is shown that the amorphous Mg–La has an catalysis on hydrogen storage performance of La@Mg system, which contributing to the dispersion of Mg and providing channels for hydrogen diffusion, facilitating hydrogenation by accelerating H atoms diffuse between the subsurface and the surface. This work provides experiment and mechanism guidance for the development of efficient hydrogen storage materials.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
SN Applied Sciences
·
2018
·Vol. 1
·期 1
·1-9
·
IF 0
Zhang Liuting,Ji Liang,Yao Zhendong,Cai Zeliang,Sun Ze,Yan Nianhua,Zhu Xinqiao
The hydrogen storage properties of MgH 2 – x wt%TiCN ( x = 5, 10, 15) composites were systematically investigated and the results show that the addition of TiCN can effectively improve the de/rehydrogenation kinetics of MgH 2 . Taken the onset dehydrogenation temperature and isothermal de/rehydrogenation kinetics into consideration, the MgH 2 –10 wt% TiCN composite was shown to have the best performance. It was found that the MgH 2 –10 wt% TiCN composite could release 4 wt% H 2 in 17.3 min at 300 °C while the as-synthesized MgH 2 could not release any hydrogen under the same condition. Besides, the MgH 2 –10 wt% TiCN composite could absorb 4.63 wt% H 2 under 3.2 MPa hydrogen pressure at 300 °C within 20 s. Compared with as-synthesized MgH 2 , the activation energy of the MgH 2 –10 wt% TiCN composite was significantly decreased from 183.76 ± 10 to 106.82 ± 5 kJ/mol. X-ray diffraction analysis revealed that the TiCN remained stable during the ball milling and the following de/rehydrogenation cycle. The catalytic mechanism was also proposed that the TiCN particles absorbed on MgH 2 not only served as charge transfer centers and accelerated the hydrogen incorporation and dissociation rate but also provided more diffusion channels for hydrogen, which contributed to the good de/rehydrogenation properties of MgH 2 .
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
RSC Advances
·
2014
·Vol. 4
·期 81
·42764-42771
·
IF 3.708
Yana Liu,Jinxin Zou,Xiaoqin Zeng,Wenjiang Ding
A Mg–Ti nano-composite has been co-precipitated from a tetrahydrofuran (THF) solution containing anhydrous magnesium chloride (MgCl2), titanium tetrachloride (TiCl4) and lithium naphthalide (LiNp) as the reducing agent. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), and pressure-composition-temperature (PCT) techniques are used to characterize phase components, microstructure and hydrogen sorption properties of the composite. The co-precipitated Mg–Ti nano-composite contains nearly 1.0 wt% of Ti distributed homogeneously on the surface or inside Mg particles having an average particle size of about 50 nm. Orthorhombic γ-MgH2 phases and tetragonal γ-TiH2 phases are obtained when the Mg–Ti nano-composite is hydrogenated at 75 °C. PCT measurements reveal the superior hydrogen absorption property of the Mg–Ti nano-composite: its maximum hydrogen capacity can reach up to 6.2 wt% within 2 h at room temperature under a hydrogen pressure of 3 MPa. The activation energy for hydrogen absorption is determined to be 50.2 kJ mol−1 H2. The hydrogenation and dehydrogenation enthalpies of the nano-composite are calculated to be −73.0 ± 1.8 and 75.8 ± 4.7 kJ mol−1 H2, close to the standard values for Mg (−74.1 ± 2.9 kJ mol−1 H2). The catalytic effects from the co-precipitated Ti and the tetragonal γ-TiH2 formed during the hydrogenation process lead to extremely fast absorption kinetics at room temperature.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2023
·Vol. 69
·期 7
·e18087
·
IF 3.7
Bo Wang,Xuhao Xie,Lurui Wan,Wenbo Zhao,Yuan Chen
In the present work, a series of deep eutectic solvents (DESs) based on organic amine as hydrogen bond acceptors (HBAs), and ethylene glycol (EG) as hydrogen bond donor (HBD) were prepared for the H 2 S absorption. Thermal decomposition temperature, HBA mass ratios, alkalinity and structure effect on absorption behavior were systematically investigated. The reaction mechanism was demonstrated by FT-IR and 1 H NMR spectroscopy. The reaction equilibrium constants, Henry constant, enthalpy and entropy change were calculated based on the thermodynamic model to reveal the interactions between DESs and H 2 S. It was found that H 2 S absorption capacities of the most of DESs with HBA/HBD mass ratio of 1:4 was close to 1 mol/mol at 303.15 K and 0.2 bar. The absorption capacity of DESs depends on the alkalinity and structure of HBAs; Additionally, a good linear correlation between the alkalinity of HBA and the absorption equilibrium constant (ln K ) of DESs to H 2 S was found.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Inorganics
·
2025
·Vol. 13
·期 3
·74
·
IF 3
Yan Chu,Shiwei Fang,Yingjue Chen,Xiaoqi Zhang,Jie Zheng,Zhenglong Li,Wubin Du,Wengang Cui,Jian Miao,Yaxiong Yang,Yongfeng Liu,Mingxia Gao,Hongge Pan
LiAlH4, characterized by high hydrogen capacity and metastable properties, is regarded as a promising hydrogen source under mild conditions. However, its reversible regeneration from dehydrogenated production is hindered thermodynamically and kinetically. Herein, we demonstrate an active Li–Al–Ti nanocrystalline alloy prepared by melt spinning and cryomilling to enable directly synthesizing nano-LiAlH4. Due to the non-equilibrium preparation methods, the grain/particle size of the alloy was reduced, stress defects were introduced, and the dispersion of the Ti catalyst was promoted. The refined Li–Al–Ti nanocrystalline alloy with abundant defects and uniform catalytic sites demonstrated a high reactivity of the particle surface, thereby enhancing hydrogen absorption and desorption kinetics. Nano-LiAlH4was directly obtained by ball milling a 5% Ti containing Li–Al–Ti nanocrystalline alloy with a grain size of 17.4 nm and Al3Ti catalytic phase distributed under 20 bar hydrogen pressure for 16 h. The obtained LiAlH4exhibited room temperature dehydrogenation performance and good reversibility. This finding provides a potential strategy for the non-solvent synthesis and direct hydrogenation of metastable LiAlH4hydrogen storage materials.
研究领域:
材料科学
·
氢能技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）