Improvement of the LiBH4 hydrogen desorption by confinement in modified carbon nanotubes

• The desorption kinetics for LiBH4 greatly promoted using melt infiltration method.
• The LiBH4 confined in modified MWCNTs shows the best desorption kinetics.
• The crystal structure of MWCNTs and SWCNTs is unchanged after ball milling.
• Ball milling introduces a great amount of structural defects in the CNTs.
• Nano-confinement is dominant on improving the hydrogen desorption of LiBH4.

The dehydrogenation kinetics of LiBH4 incorporated within various carbon nanotubes has been studied. It is demonstrated that the desorption kinetics of LiBH4 could be greatly promoted using a simple melt infiltration method and LiBH4 confined in modified multi-walled carbon nanotubes (MWCNTs) shows the best desorption kinetics. The structural properties of carbon nanotubes and confined samples are demonstrated by means of transmission electron microscopy, powder X-ray diffraction and Raman spectroscopy. The crystal structure of MWCNTs and single-walled carbon nanotubes (SWCNTs) are almost unchanged after ball milling. But high energy ball milling leads to a decrease in the average nanotube length and introduces a great amount of local disorder and structural defects in the CNTs, which may provide a considerable kinetic improvement.