Article
Environmental Sciences
Kanhaiya Chawla, Deepak Kumar Yadav, Abhinav Bajpai, Sushant Kumar, Chhagan Lal
Summary: This study investigates the improvement of hydrogen storage properties of MgH2 by using activated carbon as a catalyst in MgH2-AC nanocomposites. The results show that the presence of activated carbon helps reduce oxygen in MgO phase, leading to significantly enhanced absorption capacity and kinetics in the MgH2-AC nanocomposites. The nanocomposites also exhibit high hydrogenation properties with the presence of beta- and gamma-phases of MgH2, as supported by XRD data.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Chemistry, Physical
Jingxi Zhang, Huang Liu, Pei Sun, Chengshang Zhou, Xueyi Guo, Zhigang Zak Fang
Summary: In this study, MgO doping and air exposure methods were used to add oxygen to MgH2-TiH2 materials, and the hydrogen storage properties of these materials were systematically investigated. The results showed that MgO doping accelerated the absorption kinetics at ambient temperature, hindered the growth of Mg crystalline, and reduced the desorption temperature. On the contrary, air exposure significantly deteriorated the kinetics of MgH2-TiH2 under both ambient and high temperature. The hydrogenation kinetics of the air-exposed sample can be recovered under cycling. Our results indicated that the effect of MgO is highly dependent on the means to introduce MgO and the location of MgO in the matrix structure. Air exposure is the main factor for the degradation of hydrogen storage properties, but MgO doping positively affects the performance of Mg-based hydride.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Myong-Bom Pang, Song-Il Hong, Su-Il Ri, Jong-Chol Kim
Summary: This study investigated the properties of magnesium hydrides substituted with titanium using first principles calculation. The Mg14Ti4H36 system showed the best performance as a hydrogen storage material, with both substitution concentration and configuration playing vital roles in material properties.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Vasyl Berezovets, Andriy Kytsya, Ihor Zavaliy, Volodymyr A. Yartys
Summary: In this study, the hydrolysis of magnesium hydride in MgCl2 aqueous solutions was systematically studied, showing linear dependencies of hydrolysis rate, pH, and yield on the logarithm of MgCl2 concentration. The precipitates formed do not contain chlorine ions and consist solely of Mg(OH)2, with crystallite size increasing with MgCl2 content. A pseudo-homogeneous model best described the hydrolysis kinetics, and the presence of Mg(OH)2 was found to partially suspend the reaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Multidisciplinary
Bin Wang, Yihang Li, Jia Hao Pang, Kohei Watanabe, Ryo Takita, Shunsuke Chiba
Summary: A protocol for regio-controlled hydromagnesiation of 1,3-enynes was developed using magnesium hydride generated in situ by solvothermal treatment of sodium hydride and magnesium iodide in THF. The resulting allenylmagnesium species could be converted into tri- and tetra-substituted allenes by subsequent treatment with various carbon- and silicon-based electrophiles with the aid of CuCN as a catalyst.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Prutthipong Tsuppayakorn-aek, Rajeev Ahuja, Thiti Bovornratanaraks, Wei Luo
Summary: Based on density functional theory calculations, this study reveals that Al0.5Zr0.5H3 exhibits relatively high superconducting transition temperature under high pressure, suggesting the possibility of observing superconductivity experimentally.
Article
Metallurgy & Metallurgical Engineering
Haiguang Gao, Rui Shi, Yana Liu, Yunfeng Zhu, Jiguang Zhang, Liquan Li, Xiaohui Hu
Summary: The catalytic effects of two-dimensional Ti3C2Tx MXenes with different exposed facets on MgH2 were systematically investigated through experimental and theoretical approaches. The exposed facets were found to be the dominant factor for the catalytic activity of Ti3C2Tx towards MgH2. Ti3C2Tx with more exposed edge facets exhibited higher catalytic activity than that with more exposed basal facets and resulted in different rate-controlling steps during the de/hydrogenation process of MgH2.
JOURNAL OF MAGNESIUM AND ALLOYS
(2023)
Article
Chemistry, Physical
F. J. Antiqueira, D. R. Leiva, G. Zepon, W. J. Botta
Summary: In recent studies, it was found that high energy ball milling of Mg/MgH2 mixed with additives can reduce the temperature for H-2 absorption/desorption without altering thermodynamic properties. This research aimed to identify efficient hydrogen absorption/desorption catalysts at low temperatures, particularly at room temperature (RT). Among the additives tested in this study, MgH2-TiFe mixture showed the best performance, attributed to the strong catalytic action of TiFe and the high energy interfaces attracting hydrogen gas.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Multidisciplinary
Yihang Li, Jiahua Chen, Jaslyn Jing Wen Ng, Shunsuke Chiba
Summary: A protocol was developed to generate allylmagnesium reagents from 2-aryl-1,3-dienes using in situ generated magnesium hydride (MgH2) through solvothermal treatment of sodium hydride (NaH) and magnesium iodide (MgI2) in tetrahydrofuran (THF). Downstream functionalization of the resulting allylmagnesium reagents with carbonyl compounds or alkyl (pseudo)halides led to branched products with an allylic quaternary carbon center, while reaction with chlorosilanes resulted in regio and stereoselective formation of linear allylsilanes. Further derivatizations of the homoallylic alcohols and allylsilanes were also demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Soufiane Bahou, Hicham Labrim, Marwan Lakhal, Mohamed Bhihi, Bouchaib Hartiti, Hamid Ez-Zahraouy
Summary: By studying the effect of magnesium vacancies and hydrogen doping on magnesium hydride, it is found that they contribute to enhancing the hydrogen storage properties of the hydride by reducing desorption temperature and stability. It is noteworthy that controlling the concentrations of magnesium vacancies and hydrogen dopant atoms can regulate the desorption temperature, optimizing the practical application of the hydride in fuel cell vehicles.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Physics, Multidisciplinary
Erik Piatti, Giacomo Prando, Martina Meinero, Cesare Tresca, Marina Putti, Stefano Roddaro, Gianrico Lamura, Toni Shiroka, Pietro Carretta, Gianni Profeta, Dario Daghero, Renato S. Gonnelli
Summary: In this study, the authors demonstrate a unique superconducting phase induced by ionic liquid gating-driven hydrogen intercalation in the layered compound TiSe2. The findings suggest that hydrogen doping could produce similar effects on the electronic and phononic spectra of materials at ambient pressure as it does in near-to-room temperature superconductivity of hydrides at megabar pressures. The non-volatile control of the electronic ground state of TiSe2 via gate-controlled protonation provides a promising approach for engineering the ground state of transition metal dichalcogenides and other layered materials.
COMMUNICATIONS PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Xiaohan Liu, Xiaowei Huang, Peng Song, Chongze Wang, Liying Zhang, Peng Lv, Liangliang Liu, Weifeng Zhang, Jun-Hyung Cho, Yu Jia
Summary: A recent experiment has shown that alpha-MoB2, with a MgB2-type structure, exhibits superconductivity at -32 K under a pressure of 90 GPa, which is the highest transition temperature (Tc) among transition metal diborides. Researchers have used first-principles calculations to investigate the electronic properties of MoB2 and found that B atoms contribute significantly to electronic states near the Fermi level (EF), while the Mo dz2 orbital dominates in MoB2 and gives rise to double Van Hove singularities (VHS) in the density of states. The analysis suggests that these electronic states strongly interact with vibrational modes of Mo, leading to a large single gap and a Tc up to -37 K. Furthermore, by doping electrons into MoB2, the alignment of VHS with EF can be adjusted, resulting in an increased Tc of -43 K. These findings not only explain the high Tc observed in MoB2, but also highlight its potential as a platform for studying emergent strong electron-phonon coupling superconductivity associated with VHS.
Article
Physics, Condensed Matter
Soufiane Bahou, Hicham Labrim, Hamid Ez-Zahraouy
Summary: An ab initio study examines the impact of transition metals and vacancies on the thermodynamic properties of magnesium hydride (MgH2), focusing on decomposition temperature and gravimetric density. The results show that magnesium vacancies promote hydrogen diffusion within MgH2, while transition metals weaken the hydrogen-magnesium bond, both improving the decomposition temperature. Vacancies are more favorable than transition metal doping, with a practical concentration range of 3.3% to 4.6%. Additionally, vacancies increase the gravimetric density from 7.658 to 8.269 wt%, while transition metals reduce the density to 7.064 wt% for Mg1-xCrxH2 and 7.006 wt% for Mg1-xMnxH2.
SOLID STATE COMMUNICATIONS
(2023)
Article
Engineering, Environmental
Yongyang Zhu, Shaoyang Shen, Liuzhang Ouyang, Jiangwen Liu, Hui Wang, Zhenguo Huang, Min Zhu
Summary: This study reports an economical method to synthesize Mg(BH4)(2) by converting B-O bonds in widely available borates or boric acid to B-H. This method avoids expensive boron sources and high pressure and temperature conditions, significantly reducing costs, and could be an alternative to the current synthesis processes of Mg(BH4)(2).
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Soufiane Bahou, Hicham Labrim, Hamid Ez-Zahraouy
Summary: By using the Korringa-Kohn-Rostoker method, the researchers investigate the effects of doping with transition metals and creating magnesium vacancies on the thermodynamic properties of MgH2. The results show that the heat of formation increases with higher concentrations of magnesium vacancies and transition metals, while the decomposition temperature and stability decrease. The weak hybridization between the doped elements and hydrogen atoms, as well as the faster movement of hydrogen atoms in the structure, contribute to the improvement of the thermodynamic properties. The optimal concentrations for practical use are determined to be 6.1% for Mg1-x-yMnxH2, 6.4% for Mg1-x-yCrxH2, and 7.1% for Mg1-x-yVxH2.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)