Theoretical study of C60 as catalyst for dehydrogenation in LiBH4
Theoretical study of C60 as catalyst for dehydrogenation in LiBH4
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DOI：
10.1088/0957-4484/22/33/335401
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发表时间：
2011-02
期刊：
影响因子：
3.5
通讯作者：
R. Scheicher;Saying Li;C. M. Araujo;A. Blomqvist;R. Ahuja;R. Ahuja;P. Jena
中科院分区：
文献类型：
--
作者：
R. Scheicher;Saying Li;C. M. Araujo;A. Blomqvist;R. Ahuja;R. Ahuja;P. Jena
复合轻金属氧化物具有许多特性，这使得它们作为氢的储存介质是有吸引力的，但通常需要催化剂来降低氢解吸温度并促进可逆反应形式的氢吸收。在寻找催化剂的压倒性的重点一直是含钛化合物，但他们的行动的确切机制仍然有些模糊。最近的一项实验表明，富勒烯（C60）也可以作为硼氢化锂（LiBH 4）中氢吸收和释放的催化剂。为了理解所涉及的机制，我们采用密度泛函理论对这种复杂的金属氢化物和碳纳米材料之间的相互作用进行了详细的研究。考虑到逐步减少的氢含量在LiBH 4中，我们发现，C60的存在下，可以导致所涉及的H-去除能量的大幅减少。这种效应被解释为BHx −复合物和C60实体之间相互作用的结果。
Complex light metal hydrides possess many properties which make them attractive as a storage medium for hydrogen, but typically catalysts are required to lower the hydrogen desorption temperature and to facilitate hydrogen uptake in the form of a reversible reaction. The overwhelming focus in the search for catalysing agents has been on compounds containing titanium, but the precise mechanism of their actions remains somewhat obscure. A recent experiment has now shown that fullerenes (C60) can also act as catalysts for both hydrogen uptake and release in lithium borohydride (LiBH4). In an effort to understand the involved mechanism, we have employed density functional theory to carry out a detailed study of the interaction between this complex metal hydride and the carbon nanomaterial. Considering a stepwise reduction of the hydrogen content in LiBH4, we find that the presence of C60 can lead to a substantial reduction of the involved H-removal energies. This effect is explained as a consequence of the interaction between the BHx − complex and the C60 entity.