Nature of Ti species in the Li-Mg-N-H system for hydrogen storage / Qiang Wang in Industrial & engineering chemistry research, Vol. 48 N° 11 (Juin 2009)  

Nature of Ti species in the Li-Mg-N-H system for hydrogen storage : a theoretical and experimental investigation [texte imprimé] / Qiang Wang, Auteur ; Yungui Chen, Auteur ; Gao Niu, Auteur . - 2009 . - pp. 5250–5254.
Chemical engineering
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5250–5254

Mots-clés :	Li−  Mg−  N−  H system Ti species Li2MgN2H2 Crystal structure
Résumé :	With the properties of the Li−Mg−N−H system improved by the doped Ti species, the activation energies of these systems were estimated by an Arrhenius plot, and this elucidated a slightly decreased value with doped TiF3. To explore the nature of Ti species in the Li−Mg−N−H system, the crystal structure of Li2MgN2H2 with doped Ti was calculated and determined as Li7TiMg4(N2H2)4 by a first principle approach. As a result, the Li−N and N−H bonds in Li7TiMg4(N2H2)4 were markedly weakened, which were evaluated by the energies of Li/H vacancy formation. Moreover, the weakened Li−N bonds indicated a considerable improvement in hydrogen absorption of Li2MgN2H2 with doped Ti, which was close to the experimental results. Otherwise, the weakened N−H bonds indicated a theoretical possibility that Li2MgN2H2 could be destabilized for further hydrogen desorption at an elevated temperature.
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie900070a