EMPA, Swiss Federal Laboratories for Materials Science and Technology, Hydrogen & Energy, 8600 Dübendorf, Switzerland.
Phys Chem Chem Phys. 2012 May 14;14(18):6514-9. doi: 10.1039/c2cp40131b. Epub 2012 Mar 28.
The decomposition pathway is crucial for the applicability of LiBH(4) as a hydrogen storage material. We discuss and compare the different decomposition pathways of LiBH(4) according to the thermodynamic parameters and show the experimental ways to realize them. Two pathways, i.e. the direct decomposition into boron and the decomposition via Li(2)B(12)H(12), were realized under appropriate conditions, respectively. By applying a H(2) pressure of 50 bar at 873 K or 10 bar at 700 K, LiBH(4) is forced to decompose into Li(2)B(12)H(12). In a lower pressure range of 0.1 to 10 bar at 873 K and 800 K, the concurrence of both decomposition pathways is observed. Raman spectroscopy and (11)B MAS NMR measurements confirm the formation of an intermediate Li(2)B(12)H(12) phase (mostly Li(2)B(12)H(12) adducts, such as dimers or trimers) and amorphous boron.
LiBH4的分解途径对于其作为储氢材料的适用性至关重要。我们根据热力学参数讨论并比较了 LiBH4的不同分解途径，并展示了实现这些途径的实验方法。在适当的条件下，分别实现了两条途径，即硼的直接分解和通过 Li2B12H12的分解。在 873 K 时施加 50 巴的 H2压力或在 700 K 时施加 10 巴的 H2压力下，LiBH4被迫分解为 Li2B12H12。在 873 K 和 800 K 时 0.1 至 10 巴的较低压力范围内，观察到两条分解途径同时发生。拉曼光谱和11B MAS NMR 测量证实了中间相 Li2B12H12（主要是 Li2B12H12加合物，如二聚体或三聚体）和无定形硼的形成。
