Résumé

The lithium-intercalated fulleride Li12C60 was investigated in view of a lightweight hydrogen storage material due to the low molecular weight of its constituents. Deuterium (D2) absorption in Li12C60 shows an uptake of up to 9.5 mass % D2 (equivalent to ∼5 mass % H2 for the same stoichiometry). Under a pressure of 190 bar the onset of absorption was observed at a temperature below 100 C, which is 200 C lower than that for pure C60. Deuterium desorption was investigated by in-situ neutron powder diffraction, and at a pressure of 1 bar desorption was observed above 300 C. The ab/desorption is accompanied by a partial de/reintercalation of lithium, observed by the appearance and disappearance of LiD reflections after absorption and during desorption, respectively. A minor part of deuterium is present in ionic form in LiD, and the major part is covalently bound in a Li-depleted compound Li 12-xC60D36+y. © 2013 American Chemical Society.

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