X-ray diffraction studies of titanium and zirconium doped NaAlH4: elucidation of doping induced structural changes and their relationship to enhanced hydrogen storage properties
X-ray diffraction studies of titanium and zirconium doped NaAlH4: elucidation of doping induced structural changes and their relationship to enhanced hydrogen storage properties
复制标题
DOI：
10.1016/s0925-8388(01)01955-7
复制
发表时间：
2002-05
影响因子：
6.2
通讯作者：
Dalin Sun;T. Kiyobayashi;H. Takeshita;N. Kuriyama;C. Jensen
中科院分区：
文献类型：
--
作者：
Dalin Sun;T. Kiyobayashi;H. Takeshita;N. Kuriyama;C. Jensen
NaAlH4掺杂至10摩尔%的X射线衍射图钛或锆中的任何一种都不包含块体金属或其铝合金的布拉格峰。相反，氢化物晶格参数a和c在2摩尔%时经历显著收缩。掺杂，然后随着掺杂水平从2摩尔%增加到5摩尔%而扩大。这些结果解释了一个模型，需要取代钠阳离子的变价过渡金属阳离子和创建的Na+空位在散装氢化物晶格。
X-ray diffraction patterns of NaAlH4doped with up to 10 mol.% of either titanium or zirconium do not contain Bragg peaks for the bulk metals or their aluminum alloys. Instead the hydride lattice parameters a and c undergo significant contraction upon 2 mol.% doping and then expand as the doping level increases from 2 to 5 mol.%. These results are explained by a model that entails substitution of sodium cations by variable valence transition metal cations and the creation of Na+vacancies in the bulk hydride lattice.