Dehybridization effect in improved dehydrogenation of LiAlH4 by doping with two-dimensional Ti3C2

Lowering the thermodynamic and kinetic barriers for dehydrogenation of high-capacity hydrides has been a key challenge for the realization of practical hydrogen energy. One of the most efficient strategies is doping hydrides with catalysis while nanosizing the composites. Although numerous catalytic additives have been investigated, more efficient dopants are still under exploration, and the underling mechanism of catalysis is highly desirable. In this study, a two-dimensional (2D) layered metal carbide , Ti 3 C 2 , was doped to improve the dehydrogenation performance of LiAlH 4 . The results show that, by doping 5 wt% of Ti 3 C 2 , the initial desorption temperature of LiAlH 4 decreased significantly from 180.1 to 58.6 with 6.5 wt% of hydrogen release. Approximately 5.5 wt% of hydrogen was liberated from the LiAlH 4 +5 wt% Ti 3 C 2 sample at 200 °C within 35 min. Combining density functional theory calculations, we reveal that contact of 2D Ti 3 C 2 significantly decreases the desorption energy barrier of Al–H bonding in LiAlH 4 and accelerates the breakdown of Al–H bonding through the interfacial charge transfer and the dehybridization of the Al–H cluster.