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, Ti₃C₂, was doped to improve the dehydrogenation performance of LiAlH₄. The results show that, by doping 5 wt% of Ti₃C₂, the initial desorption temperature of LiAlH₄ 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 LiAlH₄+5 wt% Ti₃C₂ sample at 200 °C within 35 min. Combining density functional theory calculations, we reveal that contact of 2D Ti₃C₂ significantly decreases the desorption energy barrier of Al–H bonding in LiAlH₄ and accelerates the breakdown of Al–H bonding through the interfacial charge transfer and the dehybridization of the Al–H cluster.

降低高容量氢化物脱氢的热力学和动力学障碍一直是实现实际氢能的关键挑战。最有效的策略之一是在复合材料的纳米化过程中通过催化对氢化物进行掺杂。尽管已经研究了许多催化添加剂，但是仍在探索更有效的掺杂剂，并且非常需要催化的下层机理。在这项研究中，二维（2D）层状金属碳化物Ti ₃ C ₂被掺杂以改善LiAlH ₄的脱氢性能。结果表明，通过掺杂5 wt％的Ti ₃ C ₂，LiAlH ₄的初始解吸温度氢气释放量为6.5 wt％时从180.1显着降低到58.6。LiAlH ₄ +5 wt％Ti ₃ C ₂样品在200°C下35分钟内释放出约5.5 wt％的氢。结合密度泛函理论计算，我们发现2D Ti ₃ C _2的接触显着降低了LiAlH ₄中Al–H键的解吸能垒，并通过界面电荷转移和Al的去杂化作用加速了Al–H键的破坏。 -H群集。