X.Yao
,
C.Z.Wu
,
H.Wang
,
H.M.Cheng
,
G.Q.Max Lu
材料科学技术（英文）
Hydrogen storage in traditional metallic hydrides can deliver about 1.5 to 2.0 wt pct hydrogen but magnesium hydrides can achieve more than 7 wt pct. However, these systems suffer from high temperature release drawback and chemical instability problems. Recently, big improvements of reducing temperature and increasing kinetics of hydrogenation have been made in nanostructured Mg-based composites. This paper aims to provide an overview of the science and engineering of Mg materials and their nanosized composites with nanostructured carbon for hydrogen storage. The needs in research including preparation of the materials, processing and characterisation and basic mechanisms will be explored. The preliminary experimental results indicated a promising future for chemically stable hydrogen storage using carbon nanotubes modified metal hydrides under lower temperatures.
关键词:
Hydrogen storage
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null
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null
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null
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null
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null
Zhili ZHU
金属学报(英文版)
A systematic ab initio study on magnetism of the 3d transition metals (TM) from atom to monoatomic wire within density functional theory with generalized gradient approximation (GGA) was performed. The results show that the spin coupling has strong intraatomic exchange strengths about 1 eV for isolated 3d TM atoms. The magnetic moments are distinctly lower than those of free atoms for all dimers except Mn2. All the 3d TM elements exhibit magnetic ground states in the linear wire structure.
关键词:
Ab initio study
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Magnetism
,
Transition metal
