Structure and properties of complex hydride perovskite materials
Structure and properties of complex hydride perovskite materials
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DOI：
10.1038/ncomms6706
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发表时间：
2014-12
影响因子：
16.6
通讯作者：
P. Schouwink;M. Ley;A. Tissot;H. Hagemann;T. Jensen;L. Smrc̆ok;R. Černý
中科院分区：
文献类型：
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作者：
P. Schouwink;M. Ley;A. Tissot;H. Hagemann;T. Jensen;L. Smrc̆ok;R. Černý
Percent材料拥有令人难以置信的各种功能。虽然最轻的元素氢很少出现在氧化物钙钛矿晶格中，但最近观察到氢阴离子H−取代了BaTiO 3中的氧化物阴离子。在这里，我们提出了一系列30种新的复合氢化物钙钛矿型材料，基于非球形四氢硼酸根阴离子BH 4 −和涉及稀土元素的新合成方案。光物理，电子和储氢性能进行了讨论，沿着与违反直觉的趋势，在结构行为。电子结构的理论研究与密度泛函理论的固态计算。BH 4-特异性阴离子动力学被引入钙钛矿，介导机制冻结晶格不稳定性并产生高达16 × AB（BH 4）3晶胞体积的超晶胞。在这种观点中，同极双氢接触出现作为一个潜在的工具，与定制晶体的对称性，从而合并的概念，分子化学与陶瓷样的主机晶格。此外，阴离子混合BH 4 − <$X−（X−=Cl−、Br−、I−）提供了已知ABX 3卤化物的链接。
Perovskite materials host an incredible variety of functionalities. Although the lightest element, hydrogen, is rarely encountered in oxide perovskite lattices, it was recently observed as the hydride anion H−, substituting for the oxide anion in BaTiO3. Here we present a series of 30 new complex hydride perovskite-type materials, based on the non-spherical tetrahydroborate anion BH4−and new synthesis protocols involving rare-earth elements. Photophysical, electronic and hydrogen storage properties are discussed, along with counterintuitive trends in structural behaviour. The electronic structure is investigated theoretically with density functional theory solid-state calculations. BH4-specific anion dynamics are introduced to perovskites, mediating mechanisms that freeze lattice instabilities and generate supercells of up to 16 × the unit cell volume inAB(BH4)3. In this view, homopolar hydridic di-hydrogen contacts arise as a potential tool with which to tailor crystal symmetries, thus merging concepts of molecular chemistry with ceramic-like host lattices. Furthermore, anion mixing BH4−←X−(X−=Cl−, Br−, I−) provides a link to the knownABX3halides.