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Z. Naturforsch. 2014,
69b, 804 – 810
doi:10.5560/ZNB.2014-4072
Carbon-modified MgH2: Experimental and ab-initio Investigations
1 Institut de Chimie de la Matière Condensée de Bordeaux-CNRS, UPR 9048, F-33600 Pessac, France
2 Université Bordeaux 1, Institut de Chimie de Université de Bordeaux, UPR 9048, F33600 Pessac, France
3 Lebanese University, LCPM, Fanar, Beirut, Lebanon
Reprint requests to Samir F. Matar. E-mail:
matar@icmcb-bordeaux.cnrs.fr
Received March 19, 2014 / published online July 8, 2014
The results of experimental and theoretical investigations of carbon-modified MgH2 for improving its sorption performances in hydrogen storage devices are reported. Large changes on its absorption/desorption capacities have been found. The following aspects are considered: size effects where finer particles obtained by energetic ball milling enable easier penetration, catalytic effects of carbon at the surface, and entrance of small quantities of C interstitially into the MgH2 structure. The energies and charge densities as studied by DFT suggest the activation of MgH2 through a decrease of the cohesive energy of the pristine hydride and a reduced ionic charge on hydrogen.
Key words: Magnesium Hydride, Ball Milling, Carbon Doping, DFT, ELF