Novel dehydrogenation properties derived from nanoscale LiBH4

Nanoscale, amorphous LiBH4 powder with sizes from 20 to 50 nm is synthesized via a solvent evaporation process without the aid of nanoscaffolds. The nanoscale LiBH4 starts to release H2 at ∼32 °C and forms Li2B12H12 at 265 °C or lower. The amount of H2 released in the solid state from 25 to 265 °C reaches 3.5 wt.%, which is substantially higher than 0.75 wt.% H2 released by bulk LiBH4. These novel dehydrogenation properties have been discussed based on the observed improvements in both the thermodynamic driving force and reaction kinetics. The nanoscale LiBH4 not only enhances the dehydrogenation kinetics, but also alters the rate-limiting step.

The nanoscale LiBH4: (a) exhibits the largest H2 release, whereas the bulk LiBH4, (c) has the smallest H2 release with the partially oxidized nanoscale LiBH4 and (b) showing the intermediate behavior.Figure optionsDownload high-quality image (71 K)Download as PowerPoint slide