MATERIALS CHEMISTRY AND PHYSICS
·
2023
·
IF 4.6
Darvaish Khan,Jianxin Zou,Saz Muhammad,Niaz Ali Khan,Shah Saud,Subrata Panda
In this study, a MgH 2 –Ru composite is prepared by mechanical ball milling of MgH 2 and Ru powders. The microstructural analysis revealed the uniform distribution of Ru nanoparticles in the MgH 2 matrix and the formation of intermetallic compounds (i.e. Mg 6.2 Ru and Mg 1.5 Ru) after dehydrogenation of the composite. The substantial improvements in the de/hydrogenation properties of MgH 2 are due to the adjustable catalytic role of Ru under low temperature and pressure conditions. MgH 2 –Ru composite started to release hydrogen at an onset temperature of 300 °C, much lower than the mechanically milled pure MgH 2 (350 °C). Hydrogen absorption of the MgH 2 –Ru composite is relatively fast at 350 °C and stored 6.1 wt% in 5 min. At the same temperature, the hydrogenated MgH 2 –Ru composite released all stored hydrogen in less than 5 min. Compared with the catalyst-free MgH 2 , the hydrogenation and dehydrogenation activation energies of the MgH 2 –Ru composite are reduced to 65.12 ± 2.4 kJ/mol H 2 , and 97.46 ± 4.15 kJ/mol H 2 , respectively. In addition, it further demonstrated how the reversible transformation of Mg–Ru intermetallic phases induces the thermodynamic destabilization of the MgH 2 system. The presence of Ru not only facilitated the breaking of the Mg–H bond but also provided very good catalytic interfaces for enhanced de/hydrogenation properties of MgH 2 .
研究领域:
材料科学
·
能源科学
✓ 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
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氢储存
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能源材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2023
·
IF 6
Hong-Jun Lu,Dong-Hao Yuan,Chang Gao,Bi-Cheng Li,Zi-Bin Huang,Jing-Yi Yang,Pei-Qing Yuan
The effect of the timing of adding 1 wt% decalin as a hydrogen donor on heavy oil visbreaking was studied. Experiments show that either premixing decalin with heavy oil or adding decalin during the reaction accelerates the formation of light distillates and improves the efficiency of viscosity reduction. Premixing with heavy oil is an appropriate way to add decalin. After 10 min of reaction at 400 ℃, the viscosity reduction rate of the product reaches 90% and the asphaltene content of the product is 1.8 wt% lower than that of the raw heavy oil. According to theoretical calculations, the active hydrogens of decalin preferentially saturate the aromatic C radicals that are critical for condensation . The equilibrium constant of the H-donation reaches the order of 10 5 , while the activation energy of the reaction is only about 26 kJ/mol. The thermal cracking of decalin itself releases active and small-sized radicals, which accelerate visbreaking by participating in the dealkylation network of heavy oil molecules.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Cong Peng,Yongtao Li,Qingan Zhang
Magnesium hydride is a promising hydrogen storage material and how to improve its sorption kinetics is one of challenges in practical applications. In this paper, a new approach is proposed to catalyze MgH 2 with highly dispersed Ni nanoparticles by in-situ hydrogenolysis of nickelocene (NiCp 2 ) in ball milling process. After ball milling under 4 MPa hydrogen atmosphere for 15 h, the MgH 2 –16.1 wt% NiCp 2 sample exhibits a homogeneous morphology where the in-situ formed Ni nanoparticles with size of ~8 nm are highly dispersed in MgH 2 matrix. During initial dehydrogenation , Ni would react with MgH 2 to form Mg 2 Ni which inherits the configuration of its high dispersion. In the subsequent hydrogen absorption and desorption cycles, the much fine and highly dispersed Ni-based catalytic phase contributes to the superior hydrogen desorption kinetics of MgH 2 with a high-capacity retention rate of ~96% after 50 cycles. This work demonstrates that the in-situ formation of highly dispersed catalytic species is beneficial for improving hydrogen storage properties of MgH 2 .
研究领域:
材料科学
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无机化学
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能源化学
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纳米催化
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氢储能
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhe Zhang,Yusan Turap,Yongkang Wang,Yidi Wang,Zhentong Wang,Wei Wang
Thermochemical hydrogen storage technology based on iron-based materials has received significant attention owing to its low cost, safety features, and high volumetric hydrogen storage density. However, no consensus has been established on the optimal temperature range for hydrogen storage. This study investigated the impact of hydrogen storage temperature on hydrogen consumption capacity, hydrogen release capacity, and hydrogen storage energy consumption. The hydrogen storage temperature was optimized with the objectives of low energy consumption and high hydrogen storage density. The experiments were conducted using thermogravimetric analyzer and gram-scale packed-bed reactor setups, accompanied by thermodynamic and kinetic calculations. The research indicated that at 550 °C, the optimal hydrogen storage temperature, the lowest relative energy demand was 32.30 %, with the hydrogen consumption capacity reaching the theoretical maximum value of 4.8 %, and the hydrogen release capacity reaching 4.04 %. Furthermore, achieving the theoretical maximum value of hydrogen consumption capacity became exceedingly difficult when the hydrogen storage temperature exceeded 570 °C. Microstructural characterization and kinetic calculations revealed that this phenomenon was attributed to the formation of a dense iron layer on the particle surface, which impeded the solid-state diffusion of oxygen atoms. The formation of the intermediate phase wüstite was identified as the cause of the formation of the dense iron layer. Overall, this study provided theoretical support for iron-based thermochemical hydrogen storage processes and offered a perspective into the reaction behavior of the reduction of magnetite with hydrogen.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CHINESE CHEMICAL LETTERS
·
2024
·
IF 9.4
Linxin Zheng,Shuai Li,Liuting Zhang,Tao Zhong,Xiuzhen Wang,Ting Bian,Petr Senin,Ying Wu
Magnesium hydride (MgH 2 ) demonstrates immense potential as a solid-state hydrogen storage material, while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics. Herein, a MOF derived multi-phase FeNi 3 -S catalyst was specially designed for efficient hydrogen storage in MgH 2 . Experiments confirmed that the incorporation of FeNi 3 -S into MgH 2 significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption. The initial dehydrogenation temperature of the MgH 2 + 10 wt% FeNi 3 -S composite was 202°C, which was 123°C lower than that of pure MgH 2 . At 325°C, the MgH 2 + 10 wt% FeNi 3 -S composite released 6.57 wt% H 2 (fully dehydrogenated) within 1000 s. Remarkably, MgH 2 + 10 wt% FeNi 3 -S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H 2 within 30 min at 100°C. Moreover, 6.3 wt% H 2 was still retained after 20 cycles at 300°C, demonstrating the superior cycling performance of the MgH 2 + 10 wt% FeNi 3 -S composite. The activation energy fitting calculations further evidenced the addition of FeNi 3 -S enhanced the de/resorption kinetics of MgH 2 ( E a = 98.6 kJ/mol and 43.3 kJ/mol respectively). Through phase and microstructural analysis, it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg 2 Ni + Fe/MgS and MgH 2 /Mg 2 NiH 4 + Fe/MgS hydrogen storage systems. Further mechanistic analysis revealed that Mg 2 Ni/Mg 2 NiH 4 served as “hydrogen pump” and Fe/MgS served as “hydrogen diffusion channel”, thus accelerating the dissociation and recombination of hydrogen molecules. In conclusion, this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH 2 , which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.
研究领域:
材料科学
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能源存储
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2024
·
IF 4.8
Zibo Cheng,Yeqin Guan,Hong Wen,Zhao Li,Kaixun Cui,Qijun Pei,Shangshang Wang,Claudio Pistidda,Jianping Guo,Hujun Cao,Ping Chen
Lithium hydride (LiH), a saline hydride with a hydrogen density of 12.6 wt %, is highly thermostable, which hinders its extensive application in hydrogen storage. In this study, we demonstrate a distinct photodecomposition of LiH under ambient conditions. Ultraviolet–visible (UV–vis) illumination induces hydrogen release and creates surface hydrogen vacancies on LiH. The subsequent H– migration enables hydrogen desorption and the accumulation of vacancies at the subsurface, resulting in the generation of metallic Li clusters. Rehydrogenation, on the contrary, can be charged under UV–vis illumination in 1 bar H2. Such phenomena show that the thermodynamic and kinetic limits in the re/dehydrogenation of LiH can be broken under illumination, which allows hydrogen storage over the LiH surface at temperatures ∼600 K lower than those of the corresponding thermal process. This work provides new insights into the interaction of semiconducting hydrides and photons and opens an avenue for the development and optimization of materials for hydrogen storage and related photodriven reactions.
研究领域:
储氢
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材料科学
·
表面化学
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光化学
·
半导体氢化物
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Xiaohui Lu,Xinglin Yang,Jie Kong,Jianye Su,Quanhui Hou
One of the most important technologies for the sustainable development of energy in the future is solid-state hydrogen storage. This study employed etching methods to fabricate two-dimensional layered catalyst Mo 2 Ti 2 C 3 MXene, which was compared with unetched MAX phases Mo 2 Ti 2 AlC 3 and Ti 3 C 2 , as well as Mo 2 C. Through mechanical ball milling, these materials were mixed with MgH 2 to prepare composite materials, including MgH 2 + Ti 2 C 3 , MgH 2 + Mo 2 C, MgH 2 + Mo 2 Ti 2 AlC 3 , and MgH 2 + Mo 2 Ti 2 C 3 . According to the study, Mo 2 Ti 2 C 3 demonstrates the synergistic catalytic actions of Ti and Mo in contrast to Ti 2 C 3 and Mo 2 C. The composite material MgH 2 + Mo 2 Ti 2 C 3 lowers the initial dehydrogenation temperature of MgH 2 to 180 °C, which is 165 °C lower than pure MgH 2 . After 30 min at 250 °C, the dehydrogenation amount is approximately 5.85 wt%. Hydrogen absorption begins at 40 °C and reaches approximately 5.75 wt% at 150 °C. Additionally, it maintains a reversible hydrogen storage capacity of up to 96 % even after 20th cycles at 300 °C. This is because Mo 2 Ti 2 C 3 has one less layer of Al than Mo 2 Ti 2 AlC 3 , which results in a wider interlayer spacing, more active sites for MgH 2 , and facilitates hydrogen molecule dissociation and recombination.
研究领域:
材料科学
·
能源存储
·
催化
✓ 已验证
DOI
高影响因子
Journal of Magnesium and Alloys
·
2025
·
IF 13.8
Houqun Xiao,Luocai Yi,Huxu Lei,Yu Xu,Xiaoxuan Zhang,Huazhou Hu,Ruizhu Tang,Qian Li,Qingjun Chen
Magnesium hydride (MgH 2 ) has garnered significant attention as a promising material for high-capacity hydrogen storage. However, its commercial application remains challenging due to the high operating temperature and slow reaction kinetics. In this study, melt-spun Ti 45 Cr 40 Nb 15 (with a BCC phase) hydride (designated as TiCrNbH x− MS) was synthesized and used to form a nano-multiphase composite to improve the de-/rehydrogenation properties of MgH 2 through ball milling. The incorporation of TiCrNbH x− MS was shown to significantly enhance the hydrogen de-/rehydrogenation properties of MgH 2 . The MgH 2 + 20 wt% TiCrNbH x− MS composite exhibits an appealing initial dehydrogenation temperature of 163 °C and can absorb hydrogen at room temperature. Notably, it releases 5.8 wt% hydrogen in 700 s at 230 °C and recharges 4.3 wt% hydrogen in just 2 mins at 150 °C. Even after 100 cycles, it retains a reversible hydrogen capacity of 4.98 wt%. Kinetic analysis revealed that the dehydrogenation rate follows the Chou surface penetration model. Microstructural analysis showed that the FCC phase of the melt-spun TiCrNbH x− MS hydride reversibly transformed into the BCC phase during the de-/rehydrogenation process in the composite. Numerous phase interfaces were generated and uniformly dispersed on the MgH 2 surface, providing additional hydrogen diffusion pathways and heterogeneous nucleation sites for Mg/MgH 2 , thereby further improving the hydrogen de-/rehydrogenation kinetics of the system. This study offers valuable insights into the use of multiphase composites to enhance MgH 2 performance.
研究领域:
材料科学
·
储能
·
纳米技术
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催化
·
氢能
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 2
·3129-3141
·
IF 3.741
Xuelian Zhang,Ke Wang,Xin Zhang,Jianjiang Hu,Mingxia Gao,Hongge Pan,Yongfeng Liu
Summary High operation temperatures and slow reaction kinetics are major obstacles to use MgH 2 as a solid hydrogen store. We report here the synthesis of Nb 2 O 5 hollow spheres (o-Nb 2 O 5 ) with wall thickness of approximately 50 nm and mossy surfaces using a facile hydrothermal and calcination process, which showed high activity in catalysis of MgH 2 for hydrogen storage. The dehydrogenation onset temperature of MgH 2 was decreased to 195°C with 7 wt% of o-Nb 2 O 5 . More than 5.5 wt% H 2 can be desorbed at 300°C within 5 minutes. Hydrogen re-absorption starts even at 25°C and reaches 5.6 wt% within 5 minutes at 200°C. Practical hydrogen capacity stabilizes at 5.8 wt% after 10 cycles of hydrogen uptake/release. The o-Nb 2 O 5 was found to be reduced in situ by MgH 2 to low-valence Nb species during the initial dehydrogenation process, which functions as an active catalyst and leads to the enhanced dehydrogenation kinetics.
研究领域:
材料科学
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催化
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2013
·
IF 2.39
Pei Pei Yuan,Bin Hong Liu,He Peng Zhu,Wei Yuan Pan,Zhou Peng Li
In this work, the composites of LiBH 4 and AlF 3 were prepared and their hydrogen storage properties were investigated. The AlF 3 addition to LiBH 4 resulted in significant decreases in dehydrogenation temperature. All the x LiBH 4 + AlF 3 ( x = 1, 2, 3, 5) composites started to release hydrogen from about 100 °C. The dehydrogenation of the composites was accomplished through several steps, depending on the molar ratio of LiBH 4 to AlF 3 . A new phase Li 3 AlF 6 was formed during the first dehydrogenation step, which further reacted with LiBH 4 . AlB 2 was formed only at temperatures higher than 300 °C. Li 2 B 12 H 12 was detected as an intermediate. The dehydrogenation reactions have significantly reduced and thus favorable enthalpy changes. However, the reversibility of the composites needs to be improved.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Haiqiang Bai,Biao Liu,Ling Kang,Yanhong Wang,Jing Bai,Santosh Kumar Verma,Yunhua Xu
The ability of magnesium-based hydrogen storage materials to store and release hydrogen is hampered by their relatively slow rates. To address this, Mg-x% Co (x = 5, 10, 15) magnesium-rich hydrogen storage alloys were fabricated using reactive ball milling. The resulting alloys were multiphase, composed of Mg, Co, MgCo₂, and Mg₂CoH₅, which provided nucleation sites and improved hydrogen uptake. The reduced particle size and surface microcracks and pores enhanced hydrogen diffusion. The Mg-15 %Co alloy had the ability to take in 4.72 wt% hydrogen in 1 min when the temperature was set at 350°C. Hydrogenation resulted in the formation of a biphasic structure composed of Mg₂CoH₅ and Mg₆Co₂H₁₁. This structure destabilized the Mg-H bond and improved the kinetics of hydrogen release. The hydrogen release capacity first increased and then decreased with Co content, with Mg-10 %Co showing the best performance. Due to the combined action of ball milling and Co catalysis, the Mg-10 %Co alloy had an activation energy for hydrogen release of 113.65 kJ/mol, making it the alloy with the lowest such activation energy in the set. Differential scanning calorimetry (DSC) analysis confirms that cobalt addition reduces the hydrogen release peak temperature of Mg by 16.58–29.67 °C, with the Mg-10 % Co alloy exhibiting peak temperatures of 410.72–425.53 °C, attributed to synergistic decomposition of MgH₂ with intermediate hydrides like Mg₂CoH₅ and Mg₆Co₂H₁₁. The findings of this study indicate that alloying Mg-based alloys with transition elements while performing ball milling is a practical method for enhancing their hydrogen storage and release kinetics.
研究领域:
材料科学
·
能源存储
·
纳米技术
·
合金工程
✓ 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）