Improved dehydrogenation performance of LiBH4 by confinement into porous TiO2 micro-tubes

摘要

Porous TiO2 micro-tubes were fabricated by a solvothermal method, and the effect of TiO2 micro-tubes on the hydrogen desorption properties of LiBH4 was systematically investigated. It was confirmed that LiBH4 nanoparticles were successfully incorporated into these TiO2 scaffolds via a chemical impregnation method. It was revealed by results of TPD, PCT and DSC that both the lowered desorption temperature and improved kinetics of the desorption rate were due to the synergistic effects of nanoconfinement and destabilization of TiO2. The LiBH4@2TiO2 mixture (the preparation mass ratio is 1: 2) started to release hydrogen at 180 °C, and the apparent activation energy (E_a) had been reduced from 146 kJ mol~(-1) (pure LiBH4) to 121.9 kJ mol~(-1). Moreover, it is interesting that the onset desorption temperature of LiBH4@3TiO2 composite was below 100 °C, reduced by about 300 °C compared to that of pure LiBH4, which was lower than that in most of the current studies about LiBH4.