Dehydriding of Sn/MgH2Sn/MgH2 nanocomposite formed by ball milling of MgH2MgH2 with Sn

Preparation and Properties of Ball-Milled MgH₂/Al Nanocomposites for Hydrogen Storage

“…However, as shown in Fig. 2, XRD after the evacuation of the samples (I) and (II) at 573 K showed the existence of unreacted MgH 2 and/or Al in addition to the formation of Mg 17 Al 12 . Unlike the nanocomposites (III) and (IV), the samples (I) and (II) were not fully dehydrogenated at 573 K. This is consistent with the results of TDS (Fig.…”

“…As shown in Fig. 4(a), when the temperature of the sample (I) was raised to 673 K, two endothermic DSC peaks were observed at around 600 and 650 K, namely owing to the dehydrogenation of MgH 2 /Al and MgH 2 to Mg 17 Al 12 and Mg, respectively. The hydrogen desorption peak for unreacted MgH 2 remaining in the nanocomposite (I) appeared at around 650 K in DSC.…”

“…12). In the preparation of samples, MgH 2 of 3.5 g was always used, and Al (or AlH 3 ) corresponding to Al/Mg ratio = 0.706 and TEA (48 mL) as an additive were added.…”

Electronic Principles of Hydrogen Incorporation and Dynamics in Metal Hydrides

“…The most improvements have come from the catalytic approaches, in which the size of the MgH 2 particles have been reduced down to the nanometer dimensions (increasing the surface/volume ratio), their surface made more active and (or) the bulk less ordered by introduction of defects of various kinds, and by adding various elements to the system, molecules and compounds [3,4,[6][7][8]41,44,[53][54][55][56][57][58][59][60][61][62][63][64]93,94]. All above mentioned approaches could be understood and its particular relation to H-behavior resolved and established from the electronic structure point of view.…”

“…For instance, ball milling [3][4][5][6][7][8]42,43] causes mechanical deformation, surface modification, and metastable phase formation, and generally promotes the solidgas reaction: defect zones may accelerate the diffusion of hydrogen, and defect clusters may lower the barrier for nucleation of MgH 2 . Addition of metals [53,54], transition metals [3,4,[6][7][8]41,44,[55][56][57][58][59][60][61][62], metal oxides [61][62][63], or intermetallic compounds [62,64] as catalysts to mechanically milled MgH 2 , usually decreases its thermal stability and decomposition temperature and enhances sorption kinetics. Since nanosized powders are specific systems with properties controlled by their dimensions, they have been recognized as a possible solution for the problem of hydrogen sorption kinetics [7,10].…”