Promoted Hydride/Oxide Exchange in SrTiO3 by Introduction of Anion Vacancy via Aliovalent Cation Substitution
Promoted Hydride/Oxide Exchange in SrTiO3 by Introduction of Anion Vacancy via Aliovalent Cation Substitution
复制标题
通过异价阳离子取代引入阴离子空位促进 SrTiO3 中的氢化物/氧化物交换
DOI：
10.1021/acs.inorgchem.7b01845
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发表时间：
2017
影响因子：
4.6
通讯作者：
Kageyama Hiroshi
中科院分区：
文献类型：
--
作者：
Takeiri Fumitaka;Aidzu Kohei;Yajima Takeshi;Matsui Toshiaki;Yamamoto Takafumi;Kobayashi Yoji;Hester James;Kageyama Hiroshi
研究了钙钛矿结构Sr（Ti 1-yScy）O3-y/2□y/2（y≤ 0.1）中ScIII取代的SrTiIVO 3与CaH 2的拓扑化学阴离子交换反应。结果表明，少量阴离子空位（y/2）的引入对提高阴离子（H-/O2-）交换效率是至关重要的。例如，Sr（Ti0.95Sc0.05）O2.975的氢化物还原产生氢氧化物SrTi0.95Sc0.05O2.56H0.41，其中氢化物浓度相对于原始SrTiO 3增加了33%（导致SrTiO 2.76H0.24）。这一观察结果突出了阴离子空位对改善阴离子（H-/O2-）扩散的重要性，这是用于改善氧化物阴离子电导率的众所周知的策略，并且表明这种空位辅助的反应可以应用于其他阴离子交换反应（例如，F-/O2-和N3-/O2-）以扩展溶解度范围。
We investigated topochemical anion exchange reactions for a ScIII-substituted SrTiIVO3perovskite, Sr(Ti1–yScy)O3–y/2□y/2(y≤ 0.1), using CaH2. It was found that the initial introduction of a small amount of anion vacancies (y/2) is crucial to enhance the anion (H–/O2–) exchangeability. For example, hydride reduction of Sr(Ti0.95Sc0.05)O2.975yielded the oxyhydride SrTi0.95Sc0.05O2.56H0.41in which the hydride concentration is increased by 33% with respect to pristine SrTiO3(leading to SrTiO2.76H0.24). This observation highlights the importance of anion vacancies to improve anion (H–/O2–) diffusion, which is a well-known strategy for improving oxide anion conductivity, and suggests that such a vacancy-assisted reaction could be applied to other anion exchange reactions (e.g., F–/O2–and N3–/O2–) to extend the solubility range.