LiBH4 nanoparticles supported by disordered mesoporous carbon CMK-3, denoted as nano-LiBH4/C-mesoporous, were synthesized in the present work. Nano-LiBH4 in this sample was destabilized significantly, resulting in more favorable latent heat of dehydrogenation (40 kJ/mol H-2), large amount of dehydrogenation capacity (14wt%) below 600 degrees C and reversible capacity of 6.0wt% H-2 at 350 degrees C. It was revealed that such destabilization results from two kinds of mechanisms: nano-dispersion and reaction with mesoporous carbon. Both mechanisms exert synergistic effects on the dehydrogenation of nano-LiBH4 and reverse hydrogenation. (c) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.