Catalytic effect of ScCl3 on the dehydrogenation properties of LiAlH4

Abstract

The dehydrogenation properties and catalytic mechanism of ScCl3-doped LiAlH4 have been studied in detail. After milling for 10 min, hydrogen evolution from 5 mol% ScCl3-doped LiAlH4 starts at ∼90 °C, superior than that of raw LiAlH4 (∼144 °C) and as-milled LiAlH4 (∼124 °C). Moreover, this composite can release a hydrogen capacity of 3.6 wt% within 180 min at 150 °C, much higher than that of as-received LiAlH4 (1.8 wt% H2) and as-milled LiAlH4 (2.8 wt% H2) under the same condition. Results show that the catalytic effect of ScCl3 comes from the reaction product ScH2 between LiAlH4 and ScCl3, which can act as the catalyst for facilitating the dehydrogenation of LiAlH4.