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Masahiro Tatsumisago - One of the best experts on this subject based on the ideXlab platform.
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formation of li2s p2s5 solid electrolyte from n methylformamide solution
ChemInform, 2014Co-Authors: Shingo Teragawa, Keigo Aso, Kiyoharu Tadanaga, Akitoshi Hayashi, Masahiro TatsumisagoAbstract:The title solid electrolyte is prepared by drying N-methylformamide solutions of 80Li2S·20P2S5 powders (obtained by Mechanical Milling) at 150 °C for 3 h under vacuum.
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formation of li2s p2s5 solid electrolyte from n methylformamide solution
Chemistry Letters, 2013Co-Authors: Shingo Teragawa, Keigo Aso, Kiyoharu Tadanaga, Akitoshi Hayashi, Masahiro TatsumisagoAbstract:Li2S–P2S5 solid electrolyte (SE) powders were successfully reprecipitated from a liquid phase. Powders of 80Li2S·20P2S5 (mol %) SE originally prepared by Mechanical Milling were dissolved in N-meth...
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electrochemical performance of all solid state li s batteries with sulfur based composite electrodes prepared by Mechanical Milling at high temperature
Energy technology, 2013Co-Authors: Motohiro Nagao, Akitoshi Hayashi, Masahiro TatsumisagoAbstract:Sulfur–nanocarbon composites were prepared by Mechanical Milling at high temperature (155 °C), and the electrochemical performance of all-solid-state Li/S batteries was investigated with Li2S–P2S5 solid electrolytes . We aimed to increase the sulfur content in the sulfur-based composite electrodes to enhance the energy density in the Li/S batteries. The composites included 50 wt % sulfur, which is twice as high as that in the all-solid-state Li/S batteries that use sulfide-based solid electrolytes reported to date, and high-temperature Mechanical Milling resulted in a small sulfur particle size with a large contact area between the particles. The improved composites are mainly responsible for the excellent cyclability (1050 mAh g−1 for 50 cycles), high gravimetric energy density (1007 Wh kg−1), and good rate capability of the assembled batteries. These composites are promising positive-electrode materials for rechargeable Li/S batteries with high energy density. This approach of Mechanical Milling at high temperature is widely applicable and can be extended to a variety of materials in versatile energy devices as well as rechargeable lithium batteries.
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preparation of li2s p2s5 amorphous solid electrolytes by Mechanical Milling
Journal of the American Ceramic Society, 2004Co-Authors: Akitoshi Hayashi, Masahiro Tatsumisago, Shigenori Hama, Hideyuki Morimoto, Tsutomu MinamiAbstract:Amorphous solid electrolytes in the Li2S–P2S5 system were prepared successfully from a mixture of crystalline Li2S and P2S5, using a Mechanical Milling technique. The amorphous-forming region was extended to higher Li2S compositions by Mechanical Milling, compared with melt quenching. The pelletized samples of the 75Li2S·25P2S5 (on a mole-percent basis) amorphous powders obtained by Mechanical Milling for 20 h exhibited high conductivity (2 × 10−4 S/cm at room temperature) and an activation energy for conduction of 34 kJ/mol. The lithium-ion transport number of the amorphous powders was almost unity.
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characterization of li2s sis2 lixmoy m si p ge amorphous solid electrolytes prepared by melt quenching and Mechanical Milling
Solid State Ionics, 2002Co-Authors: Akitoshi Hayashi, Masahiro Tatsumisago, Hideki Yamashita, Tsutomu MinamiAbstract:Abstract The oxysulfide amorphous materials in the systems 95(0.6Li 2 S·0.4SiS 2 )·5Li x MO y (M=Si, P, and Ge) were prepared by melt-quenching and Mechanical Milling techniques. These amorphous materials exhibited high conductivity over 10 −4 S cm −1 at room temperature, a lithium transport number of unity, and a wide potential window of 10 V. The solid-state cells with the oxysulfide amorphous materials as solid electrolytes worked as lithium secondary batteries and exhibited excellent cycling performance over 100 times. The local structure of the Mechanically milled amorphous materials containing Li 4 SiO 4 was similar to that of the corresponding melt-quenched glasses, in which the SiS 4 and SiOS 3 tetrahedral units were mainly present. The SiO n S 4− n ( n =1, 2, 3) tetrahedral units were formed in the case of the addition of Li 4 SiO 4 and Li 4 GeO 4 to the base sulfide system, while these units were not present in the addition of Li 3 PO 4 . We have concluded that the reactivity of Li x MO y derived from its basicity affected the structure and formation process of the oxysulfide materials prepared by Mechanical Milling.
Akitoshi Hayashi - One of the best experts on this subject based on the ideXlab platform.
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formation of li2s p2s5 solid electrolyte from n methylformamide solution
ChemInform, 2014Co-Authors: Shingo Teragawa, Keigo Aso, Kiyoharu Tadanaga, Akitoshi Hayashi, Masahiro TatsumisagoAbstract:The title solid electrolyte is prepared by drying N-methylformamide solutions of 80Li2S·20P2S5 powders (obtained by Mechanical Milling) at 150 °C for 3 h under vacuum.
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formation of li2s p2s5 solid electrolyte from n methylformamide solution
Chemistry Letters, 2013Co-Authors: Shingo Teragawa, Keigo Aso, Kiyoharu Tadanaga, Akitoshi Hayashi, Masahiro TatsumisagoAbstract:Li2S–P2S5 solid electrolyte (SE) powders were successfully reprecipitated from a liquid phase. Powders of 80Li2S·20P2S5 (mol %) SE originally prepared by Mechanical Milling were dissolved in N-meth...
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electrochemical performance of all solid state li s batteries with sulfur based composite electrodes prepared by Mechanical Milling at high temperature
Energy technology, 2013Co-Authors: Motohiro Nagao, Akitoshi Hayashi, Masahiro TatsumisagoAbstract:Sulfur–nanocarbon composites were prepared by Mechanical Milling at high temperature (155 °C), and the electrochemical performance of all-solid-state Li/S batteries was investigated with Li2S–P2S5 solid electrolytes . We aimed to increase the sulfur content in the sulfur-based composite electrodes to enhance the energy density in the Li/S batteries. The composites included 50 wt % sulfur, which is twice as high as that in the all-solid-state Li/S batteries that use sulfide-based solid electrolytes reported to date, and high-temperature Mechanical Milling resulted in a small sulfur particle size with a large contact area between the particles. The improved composites are mainly responsible for the excellent cyclability (1050 mAh g−1 for 50 cycles), high gravimetric energy density (1007 Wh kg−1), and good rate capability of the assembled batteries. These composites are promising positive-electrode materials for rechargeable Li/S batteries with high energy density. This approach of Mechanical Milling at high temperature is widely applicable and can be extended to a variety of materials in versatile energy devices as well as rechargeable lithium batteries.
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preparation of li2s p2s5 amorphous solid electrolytes by Mechanical Milling
Journal of the American Ceramic Society, 2004Co-Authors: Akitoshi Hayashi, Masahiro Tatsumisago, Shigenori Hama, Hideyuki Morimoto, Tsutomu MinamiAbstract:Amorphous solid electrolytes in the Li2S–P2S5 system were prepared successfully from a mixture of crystalline Li2S and P2S5, using a Mechanical Milling technique. The amorphous-forming region was extended to higher Li2S compositions by Mechanical Milling, compared with melt quenching. The pelletized samples of the 75Li2S·25P2S5 (on a mole-percent basis) amorphous powders obtained by Mechanical Milling for 20 h exhibited high conductivity (2 × 10−4 S/cm at room temperature) and an activation energy for conduction of 34 kJ/mol. The lithium-ion transport number of the amorphous powders was almost unity.
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characterization of li2s sis2 lixmoy m si p ge amorphous solid electrolytes prepared by melt quenching and Mechanical Milling
Solid State Ionics, 2002Co-Authors: Akitoshi Hayashi, Masahiro Tatsumisago, Hideki Yamashita, Tsutomu MinamiAbstract:Abstract The oxysulfide amorphous materials in the systems 95(0.6Li 2 S·0.4SiS 2 )·5Li x MO y (M=Si, P, and Ge) were prepared by melt-quenching and Mechanical Milling techniques. These amorphous materials exhibited high conductivity over 10 −4 S cm −1 at room temperature, a lithium transport number of unity, and a wide potential window of 10 V. The solid-state cells with the oxysulfide amorphous materials as solid electrolytes worked as lithium secondary batteries and exhibited excellent cycling performance over 100 times. The local structure of the Mechanically milled amorphous materials containing Li 4 SiO 4 was similar to that of the corresponding melt-quenched glasses, in which the SiS 4 and SiOS 3 tetrahedral units were mainly present. The SiO n S 4− n ( n =1, 2, 3) tetrahedral units were formed in the case of the addition of Li 4 SiO 4 and Li 4 GeO 4 to the base sulfide system, while these units were not present in the addition of Li 3 PO 4 . We have concluded that the reactivity of Li x MO y derived from its basicity affected the structure and formation process of the oxysulfide materials prepared by Mechanical Milling.
Deliang Zhang - One of the best experts on this subject based on the ideXlab platform.
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a nanograins attached and ultrathin cu flake powder fabricated by high energy Mechanical Milling and dealloying
Materials Letters, 2020Co-Authors: M Zhang, Deliang Zhang, Mianmian Ruan, Jun Wang, Jiamiao LiangAbstract:Abstract Metal powders with hierarchical nanostructures are generally designed and fabricated by dealloying with or without assistance of other processes. However, they are mainly nanoporous metal powders and their derivatives which have limited applications, so metal powders with novel nanostructures should be explored further for various applications. Herein, high energy Mechanical Milling and dealloying were combined for fabricating metal powders with controllable nanostructures. As an example, a nanograins-attached and ultrathin Cu flake powder was fabricated by partial Mechanical alloying of a Cu-42 wt%Al powder mixture and subsequent dealloying. The dealloyed Cu powder particles had ultrathin flaky shapes with numerous Cu nanograins being attached to their surfaces, and the microstructure of the as-milled Cu-42 wt%Al powder particles and the dealloyed Cu particles were studied to elucidate the formation mechanism of the unique morphology of the dealloyed Cu powder.
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factors controlling the tensile properties of ultrafine structured cu 5vol al2o3 nanocomposite prepared by high energy Mechanical Milling and powder compact extrusion
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2013Co-Authors: Dengshan Zhou, Deliang Zhang, Charlie Kong, Paul MunroeAbstract:Abstract The microstructures and tensile properties of two ultrafine structured Cu–5vol%Al2O3 nanocomposite samples made by a combination of high energy Mechanical Milling of a mixture of Cu powder and gamma Al2O3 nanopowder and powder compact extrusion were studied. The sample extruded at 750 °C exhibited a microstructure consisting of Cu grains with sizes in the range of 100–500 nm and a dispersion of Al2O3 nanoparticles with sizes in the range of 20–345 nm. With the extrusion temperature increasing to 900 °C, the Cu grain sizes remained almost unchanged, but a large fraction of the Al2O3 nanoparticles were dissolved, leading to possible formation of nanometer sized Al3+/O2− clusters. This microstructural difference of the two samples causes an interesting difference in tensile properties, with the sample extruded at 900 °C showing approximately 150 MPa higher yield strength and ultimate tensile strength and also better ductility than the sample extruded at 750 °C. It appears that this significant beneficial effect of dissolution of Al2O3 nanoparticles is mainly caused by the significant strengthening effect of the nanometer sized Al3+/O2− clusters through Orowan mechanism.
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Microstructural evolution during Mechanical Milling of Ti/Al powder mixture and production of intermetallic TiAl cathode target
Journal of Materials Science, 2012Co-Authors: Brian Gabbitas, Stella Raynova, Deliang ZhangAbstract:Titanium aluminides are of great technological interest because of their attractive Mechanical properties. Mechanical Milling/alloying is a promising powder metallurgical technique, which can achieve ultrafine, uniform and manipulable microstructures. In this study, we employed a recently revisited discus mill to produce a composite Ti–(50–57) at.%Al powder feedstock, which is suitable for hot consolidation to produce bulk cathode targets for physical vapour deposition (PVD) coatings. The effects of Milling time, quantity of process control agent (PCA) and discus-to-powder weight ratio (DPR) on the microstructure evolution of the attendant Ti/Al composite powder were investigated in detail. It was found that to produce Ti/Al composite powders with a fine particle size and a uniform microstructure, the practicable processing parameters should be 2 or 3% isopropanol addition as PCA, 12 h of Milling time and at least 13:1 DPR weight ratio. Cathode targets were produced by hot isostatic pressing (HIPing) the as-milled powders. The targets were then used to produce a PVD TiAlN coating which had an average microhardness of 2400 HV.
Tsutomu Minami - One of the best experts on this subject based on the ideXlab platform.
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preparation of li2s p2s5 amorphous solid electrolytes by Mechanical Milling
Journal of the American Ceramic Society, 2004Co-Authors: Akitoshi Hayashi, Masahiro Tatsumisago, Shigenori Hama, Hideyuki Morimoto, Tsutomu MinamiAbstract:Amorphous solid electrolytes in the Li2S–P2S5 system were prepared successfully from a mixture of crystalline Li2S and P2S5, using a Mechanical Milling technique. The amorphous-forming region was extended to higher Li2S compositions by Mechanical Milling, compared with melt quenching. The pelletized samples of the 75Li2S·25P2S5 (on a mole-percent basis) amorphous powders obtained by Mechanical Milling for 20 h exhibited high conductivity (2 × 10−4 S/cm at room temperature) and an activation energy for conduction of 34 kJ/mol. The lithium-ion transport number of the amorphous powders was almost unity.
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characterization of li2s sis2 lixmoy m si p ge amorphous solid electrolytes prepared by melt quenching and Mechanical Milling
Solid State Ionics, 2002Co-Authors: Akitoshi Hayashi, Masahiro Tatsumisago, Hideki Yamashita, Tsutomu MinamiAbstract:Abstract The oxysulfide amorphous materials in the systems 95(0.6Li 2 S·0.4SiS 2 )·5Li x MO y (M=Si, P, and Ge) were prepared by melt-quenching and Mechanical Milling techniques. These amorphous materials exhibited high conductivity over 10 −4 S cm −1 at room temperature, a lithium transport number of unity, and a wide potential window of 10 V. The solid-state cells with the oxysulfide amorphous materials as solid electrolytes worked as lithium secondary batteries and exhibited excellent cycling performance over 100 times. The local structure of the Mechanically milled amorphous materials containing Li 4 SiO 4 was similar to that of the corresponding melt-quenched glasses, in which the SiS 4 and SiOS 3 tetrahedral units were mainly present. The SiO n S 4− n ( n =1, 2, 3) tetrahedral units were formed in the case of the addition of Li 4 SiO 4 and Li 4 GeO 4 to the base sulfide system, while these units were not present in the addition of Li 3 PO 4 . We have concluded that the reactivity of Li x MO y derived from its basicity affected the structure and formation process of the oxysulfide materials prepared by Mechanical Milling.
Yunfeng Zhu - One of the best experts on this subject based on the ideXlab platform.
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improved dehydriding property of polyvinylpyrrolidone coated mg ni hydrogen storage nano composite prepared by hydriding combustion synthesis and wet Mechanical Milling
Progress in Natural Science: Materials International, 2018Co-Authors: Linglong Yao, Huihui Han, Yana Liu, Yunfeng Zhu, Yao ZhangAbstract:Abstract In this work, polyvinylpyrrolidone (PVP) coated Mg95Ni5 nano-composites were prepared by hydriding combustion synthesis (HCS) plus wet Mechanical Milling (WM) with tetrahydrofuran (THF) and donated as WM-x wt% PVP (x = 1, 3, 5 and 7) respectively. The phase compositions, microstructures and dehydriding property, as well as the co-effect of PVP and THF were investigated in detail. XRD results showed that the average crystal size of MgH2 in the milled Mg95Ni5 decreased from 23 nm without PVP to 18 nm with 1 wt% PVP. The peak temperature of dehydrogenation of MgH2 in the milled Mg95Ni5 decreased from 293.0 °C without THF to 250.4 °C with THF. The apparent activation energy for decomposition of MgH2 in WM-7 wt% PVP was estimated to be 66.94 kJ/mol, which is 37.70 kJ/mol lower than that of milled Mg95Ni5 without THF and PVP. PVP and THF can facilitate the refinement of particle size during Mechanical Milling process. Attributed to small particle sizes and synergistic effect of PVP and THF, the composites exhibit markedly improved dehydriding properties.
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catalytic mechanism of nb2o5 and nbf5 on the dehydriding property of mg95ni5 prepared by hydriding combustion synthesis and Mechanical Milling
International Journal of Hydrogen Energy, 2009Co-Authors: Yunfeng ZhuAbstract:Abstract The catalytic mechanism of Nb 2 O 5 and NbF 5 on the dehydriding property of Mg 95 Ni 5 prepared by hydriding combustion synthesis and Mechanical Milling (HCS + MM) was studied. It was shown that NbF 5 was more efficient than Nb 2 O 5 in improving the dehydriding property. In particular, the dehydriding temperature onset decreases from 460 K for Mg 95 Ni 5 to 450 K for Mg 95 Ni 5 with 2.0 at.% Nb 2 O 5 , whereas it decreases to 410 K for that with 2.0 at.% NbF 5 . By means of X-ray diffraction and X-ray photoelectron spectroscopy, it was confirmed that the interaction between the Nb ions and the H atoms and that between the anions (O 2− or F − ) and Mg 2+ existed in Mg 95 Ni 5 doped with Nb 2 O 5 or NbF 5. Further, the pressure–concentration-isotherms analysis clarified that these interactions destabilized the Mg–H bonding, and that NbF 5 had a better effect on the destabilization of the Mg–H bonding than Nb 2 O 5 contributing to the better dehydriding property of (Mg 95 Ni 5 )2.0−NbF 5 .
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hydriding characteristics of mg2ni prepared by Mechanical Milling of the product of hydriding combustion synthesis
International Journal of Hydrogen Energy, 2007Co-Authors: Xiaofeng Liu, Yunfeng ZhuAbstract:Abstract Hydriding combustion synthesis (HCS) and Mechanical Milling (MM) are both well-known methods for production of magnesium-based hydrogen storage alloys. The former can produce high active hydride by a simple process, and the latter can synthesis various metastable hydrogen storage materials such as nanocrystalline, amorphous and extended solid solutions phases with excellent hydrogen sorption properties. In the present study, HCS and MM were combined, aiming to decrease sorption temperature for Mg 2 Ni . The high active Mg 2 NiH 4 , synthesized by HCS, was Mechanically milled for 0.5, 6, 40 and 80 h with 5 wt% of graphite under argon atmosphere. The effect of the Milling process on the morphology and crystal structural of Mg 2 NiH 4 were investigated by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The hydrogen storage properties were examined by a Sieverts type apparatus. The nanocrystalline Mg 2 NiH 4 milled for 40 h has the best sorption kinetics, which can absorb 2.4 wt% hydrogen at 303 K within 100 s in the first cycle. Several reasons are considered to explain the improvement in hydriding kinetics.