Hydrogen storage and structure variation in Mg/Pd multi-layer film

Reactions in a multilayered Si (substrate)/Ta/Mg/Fe/Ta/Pd thin-film structure during annealing and deuterium absorption

“…1B clearly shows that the Pd layer has decreased in thickness and there is a uniform rise in the SLD of the Mg layer, indicating the integration of higher SLD Pd atoms. There is a large body of experimental literature on the interaction of Mg and Pd thin films [41][42][43][44][45][46][47]. The general consensus is that these two elements readily form one or multiple stable intermetallics upon annealing or hydrogen sorption.…”

“…On the other hand, for Mg/Pd bilayer thin films, the formation of Mg 5 Pd 2 has even been reported at RT [42], resulting in the functional deterioration of the switchable mirrors based on bilayer Mg-X/ Pd thin-film geometry [51,52]. In a multilayered Mg/Pd thin-film system [46], Mg 6 Pd was formed after activation (at 473 K and 30 bar H 2 ), and after cycling there was a mixture of Mg 6 Pd, Mg 5 Pd 2 and MgPd. Tan et al [45] demonstrated that Mg films with Pd or Pd/Fe caps were not reversibly hydrogenated (at 250°C and 2.5 bar H 2 ), due to the extensive formation of Mg 6 Pd intermetallic phase.…”

Mg-Based Thin Films as Model Systems in the Search for Optimal Hydrogen Storage Materials

“…The Mg/Pd multilayered films activated at 474 K for 2 h under 30 bar of H2 pressure transformed completely into the Mg6Pd phase [47]. After three cycles the films consisted of a mixture of MgPd, Mg5Pd2, and Mg6Pd intermetallics phases.…”

A catalytic effect on hydrogen absorption kinetics in Pd/Ti/Mg/Ti multilayer thin films

“…Nevertheless, Mg based materials have critical drawbacks such as high dehydrogenation reaction temperature (>350°C), high thermodynamic stability (DH = À75 kJ/mol), and slow Mg H 2 reaction kinetics [1]. A number of approaches to improve the reaction kinetics of Mg through modification of hydrogenation temperatures have been studied, including bulk powder ball milling [2,3] and the use of additives [4,5], catalysts [6][7][8][9], and thin films [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. In particular, in Mg based thin films with transition metal catalysts have been demonstrated to be an effective way to enhance the performance of magnesium hydrides.…”

“…In particular, in Mg based thin films with transition metal catalysts have been demonstrated to be an effective way to enhance the performance of magnesium hydrides. For example, studies on Mg/Pd films showed that Pd not only prevents the oxidation of Mg but also acts as a catalyst [10][11][12][13][14][15][16]. However, poor hydrogenation kinetics was observed since binary intermetallic Mg Pd alloys were formed at 373 K [12,15].…”