Reversible hydrogen storage from 6LiBH4-MCl3 (M= Ce, Gd) composites by in-situ formation of MgH2.

F. C. GENNARI; L. FERNÁNDEZ ALBANESI; J. A. PUSZKIEL; P. ARNEODO LAROCHETTE

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2011 vol. 36 p. 563 - 570

0360-3199

The hydrogen sorption properties of as-milled 6LiBH4-MCl3 composites (M=Ce, Gd) have been investigated. The chemical interaction between metal halides and LiBH4 decreases the dehydrogenation temperature in comparison with as–milled LiBH4. Hydrogen desorption starts at 220 °C with the decomposition of M(BH4)3 formed during milling and proceeds through destabilization of LiBH4 by in–situ formed MH2. It is also demonstrated that LiBH4-MH2 composite can be rehydrogenated under 6.0 MPa of hydrogen at 400 ºC for 2 h, even when desorption was performed under vacuum conditions. Hydrogen back pressure promotes the Gd and Ce borides formation, with beneficial effect on the reversibility of LiBH4-CeCl3 composite. A new 6LiBH4-CeCl3-3LiH composite shows promissory hydrogen storage properties after milling via the formation of destabilized 6LiBH4-CeH2+x system by the interaction between CeCl3 and LiH.