Zang Lei, Liu Song, Guo Huinan, Chang Xiaoya, Xu Xiangqian, Jiao Lifang, Yuan Huatang, Wang Yijing
Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin, 300071, P.R. China.
Global Energy Interconnection Research Institute, Beijing, 102211, P.R. China.
Chem Asian J. 2018 Feb 2;13(3):350-357. doi: 10.1002/asia.201701649. Epub 2018 Jan 15.
Lithium alanate (LiAlH ) is of particular interest as one of the most promising candidates for solid-state hydrogen storage. Unfortunately, high dehydrogenation temperatures and relatively slow kinetics limit its practical applications. Herein, 3D flower-like nanocrystalline Ni/C, composed of highly dispersed Ni nanoparticles and interlaced carbon flakes, was synthesized in situ. The as-synthesized nanocrystalline Ni/C significantly decreased the dehydrogenation temperature and dramatically improved the dehydrogenation kinetics of LiAlH . It was found that the LiAlH sample with 10 wt % Ni/C (LiAlH -10 wt %Ni/C) began hydrogen desorption at approximately 48 °C, which is very close to ambient temperature. Approximately 6.3 wt % H was released from LiAlH -10 wt %Ni/C within 60 min at 140 °C, whereas pristine LiAlH only released 0.52 wt % H under identical conditions. More importantly, the dehydrogenated products can partially rehydrogenate at 300 °C under 4 MPa H . The synergetic effect of the flower-like carbon substrate and Ni active species contributes to the significantly reduced dehydrogenation temperatures and improved kinetics.
铝酸锂（LiAlH ）作为固态储氢最有前景的候选材料之一，备受关注。不幸的是，其较高的脱氢温度和相对较慢的动力学限制了它的实际应用。在此，原位合成了由高度分散的镍纳米颗粒和交错的碳片组成的三维花状纳米晶Ni/C。所合成的纳米晶Ni/C显著降低了铝酸锂的脱氢温度，并极大地改善了其脱氢动力学。研究发现，含有10 wt % Ni/C的铝酸锂样品（LiAlH -10 wt %Ni/C）在约48 °C开始氢解吸，这非常接近环境温度。在140 °C下，LiAlH -10 wt %Ni/C在60 min内释放出约6.3 wt %的氢，而原始的铝酸锂在相同条件下仅释放0.52 wt %的氢。更重要的是，脱氢产物在300 °C、4 MPa氢气压力下可部分再氢化。花状碳基底和镍活性物种的协同作用导致脱氢温度显著降低和动力学得到改善。
