NanoFormulation2012, Barcelona, İspanya, 28 Mayıs - 01 Haziran 2012
A
facile method for the preparation of nearly monodisperse Ru nanoparticles (NPs)
and their record catalytic activity in the hydrolytic dehydrogenation of
ammonia borane (AB) for chemical hydrogen storage are reported herein. Ru NPs
were prepared by a novel protocol comprising the thermal decomposition and
concomitant reduction of ruthenium(III) acetylacetonate (Ru(acac)3)
in the presence of oleylamine (OAm) and benzylether (BE). In the protocol, OAm
served as both a stabilizer and reducing agent and BE used as a solvent. Ru NPs
were supported on aluminum oxide nanopowder (Ru@Al2O3)
via a simple liquid impregnation method before their use as catalyst for the
dehydrogenation of AB in water. Without any special treatment to remove the
surfactants, Ru@Al2O3 showed high catalytic activity in
the hydrolytic dehydrogenation of AB providing an initial turnover frequency
(TOF) of 39.6 mol H2.(mol
Ru.min)-1. Their catalytic performance was further enhanced
dramatically by the acetic acid treatment and the initial TOF value is increased to 83.3 mol H2.(mol
Ru.min)-1 that is the highest among the Ru catalysts and even higher
than Pt-based catalysts tested in the hydrolysis of AB. Additionally, the work reported here includes a
wealthy collection of kinetic data to determine the rate law and apparent
activation parameters for the catalytic dehydrogenation of AB in water.