Investigation of the dehydrogenation behavior of the 2LiBH4:CaNi5 multicomponent hydride system
Investigation of the dehydrogenation behavior of the 2LiBH4:CaNi5 multicomponent hydride system
复制标题
DOI：
10.1016/j.ijhydene.2014.12.059
复制
发表时间：
2015-02
影响因子：
7.2
通讯作者：
M. Meggouh;D. Grant;Oliver Deavin;M. Brunelli;T. Hansen;G. Walker
中科院分区：
文献类型：
--
作者：
M. Meggouh;D. Grant;Oliver Deavin;M. Brunelli;T. Hansen;G. Walker
LiBH4作为一种潜在的储氢材料，由于其高达18.5wt%的储氢容量而备受关注。然而，LiBH4仅在高于600 °C的温度下释放其全部氢容量，并且需要至少350 bar的氢压力来还原最终产品。脱氢温度可以通过热力学调节来改变，通过添加反应剂导致较低的脱氢焓。大多数多组分氢化物体系显示出高于300 °C的脱氢温度，使得它们不太适合汽车应用。本文报道了2LiBH_4：CaNi_5体系中LiBH_4在低于270 °C熔融温度下的固态分解。原位中子衍射测量证实，分解在200 °C下以固态发生，形成LiD、CaD 2、Ni3B和Ni2B相作为最终产物。通过SEM和TEM测量进一步支持固态分解，显示纳米晶体颗粒的存在。
LiBH4has gained much attention as a potential hydrogen storage material due to its high hydrogen storage capacity of 18.5 wt%. However, LiBH4only releases its full hydrogen capacity at temperatures greater than 600 °C and requires hydrogen pressures of at least 350 bar to rehydrogenate the end products. The dehydrogenation temperature can be altered by thermodynamic tuning through the addition of a reactive agent resulting in a lower enthalpy of dehydrogenation. Most multicomponent hydride systems display dehydrogenation temperatures above 300 °C, making them less desirable for automotive applications. In this work we report the solid-state decomposition of LiBH4in the 2LiBH4:CaNi5system below the LiBH4melting temperature of 270 °C. In situ neutron diffraction measurements confirmed the decomposition took place in the solid state at 200 °C, forming LiD, CaD2, Ni3B and Ni2B phases as end products. The solid-state decomposition was further supported by SEM and TEM measurements showing the presence of nano-crystalline particles.