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• 作者：Wen Li ; Ralph H. Scheicher ; C. Moyss Arajo ; Guotao Wu ; Andreas Blomqvist ; Chenzhang Wu ; Rajeev Ahuja ; Yuan Ping Feng ; Ping Chen
• 刊名：Journal of Physical Chemistry C
• 出版年：2010
• 出版时间：November 11, 2010
• 年：2010
• 卷：114
• 期：44
• 页码：19089-19095
• 全文大小：390K
• 年卷期：v.114,no.44(November 11, 2010)
• ISSN：1932-7455

文摘

Lithium amidoborane−ammonia borane (LiNH₂BH₃·NH₃BH₃, LiAB·AB for short) was synthesized recently. Compared with lithium amidoborane (LiNH₂BH₃, LiAB for short) and ammonia borane (NH₃BH₃, AB for short), this new ammonia borane derivative has better dehydrogenation kinetics and releases 14.8 wt % hydrogen with peak temperatures at ca. 80 and 140 °C, respectively. In this report, first-principles calculations were employed to reveal the differences in dehydrogenation properties of AB, LiAB, and LiAB·AB. Furthermore, we attempted to correlate the crystal structure and electronic properties with dehydrogenation performance. The results show that Li⁺ cations play similar roles in LiAB·AB as in LiAB in destabilizing the B−H and N−H bonds, and the mechanism of the first-step dehydrogenation of LiAB·AB is likely via the dissociation and combination of hydridic H^δ−(B) from LiAB molecule and protonic H^δ+(N) from the adjacent AB molecule, rather than from the [LiAB] or [AB] layer alone, resulting in the desorption of H₂ at lower temperatures.