纳米限域LiBH_4/Mg(AlH_4)_2复合体系的脱氢特性

Hydrogen Release from the Nanoconfined LiBH_4/Mg(AlH_4)_2Composites

配位氢化物LiBH4的低温脱氢是制约其实际应用的技术瓶颈之一。采用纳米限域来进一步改善LiBH4/Mg(AlH4)2失稳体系的热解脱氢性能,用X射线衍射(XRD)、扫描电镜(SEM)和能谱(EDX)分别对其晶体结构、微观形貌和元素面分布进行表征,并采用差热分析(DSC)及热重分析(TG)研究样品的脱氢过程。结果表明,纳米限域下LiBH4/Mg(AlH4)2复合体系的脱氢性能得到了显著改善,与纯LiBH4/Mg(AlH4)2体系相比,纳米限域作用不仅使复合体系的初始脱氢温度降低了70℃,而且还将脱氢反应动力学性能提高了近7倍。

One of the key scientific issues in the application of LiBI-L is to release hydrogen at low temperature. The nanoconfmement of LiBHdMg（AII-L）2 destabilized system was adopted to further improve its dehydriding properties. X-ray diffraction （XRD）, scanning electron microscopy （SEM） and energy-dispersive X-ray （EDX） were performed to characterize its microstructures, morphologies and elemental mapping. Differential scanning calorimetry （DSC） and thermogravimetric analysis （TG） was used to study its dehydriding progresses. The results show that nanoconfmement is an effective strategy for promoting the dehydrogenation of LiBH4/Mg（A1H4）2 system. Compared to pure LiBH4/ Mg（AIH）2 sample, the nanoconfined sample not only has a reduced onset temperature by 70℃, but also exhibits a kinetics with nearly seven times faster.