In the present work, the catalytic effect of TiF3 on the dehydrogenation properties of LiAlH4 has been investigated. Decomposition of LiAlH4 occurs during ball milling in the presence of 4 mol% TiF3. Different ball milling times have been used, from 0.5 h to 18 h. With ball milling time increasing, the crystallite sizes of LiAlH4 get smaller (from 69 nm to 43 nm) and the dehydrogenation temperature becomes lower (from 80 degrees C to 60 degrees C). Half an hour ball milling makes the initial dehydrogenation temperature of doped LiAlH4 reduce to 80 degrees C, which is 70 degrees C lower than as-received LiAlH4. About 5.0 wt.% H-2 can be released from TiF3-doped LiAlH4 after 18 h ball milling in the range of 60 degrees C-145 degrees C (heating rate 2 degrees C min(-1)). TiF3 probably reacts with LiAlH4 to form the catalyst, TiAl3. The mechanochemical and thermochemical reactions have been clarified. However, the rehydrogenation of LiAlH4/Li3AlH6 can not be realized under 95 bar H-2 in the presence of TiF3 because of their thermodynamic properties. (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.