Reversible magnesium and aluminium ions insertion in cation-deficient anatase TiO2
Reversible magnesium and aluminium ions insertion in cation-deficient anatase TiO2
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DOI：
10.1038/nmat4976
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发表时间：
2017-11-01
期刊：
影响因子：
41.2
通讯作者：
Dambournet, Damien
中科院分区：
文献类型：
--
作者：
Koketsu, Toshinari;Ma, Jiwei;Dambournet, Damien
与单价的锂离子或钠离子相比，多价离子（如Mg²⁺和Al³⁺）在电极材料中的可逆嵌入仍然是一个难以实现的目标。在此，我们展示了一种在锐钛矿型TiO₂中实现Mg²⁺和Al³⁺可逆嵌入的新策略，该策略通过异价掺杂来实现，引入大量作为嵌入位点的钛空位。我们提供了广泛的实验和理论表征，结果表明多价离子优先嵌入钛空位，与纯TiO₂相比能够获得更高的容量。这一结果凸显了利用缺陷化学来释放已知材料的电化学活性的可能性，为实用多价电池的材料化学设计提供了一种新策略。
In contrast to monovalent lithium or sodium ions, the reversible insertion of multivalent ions such as Mg2+ and Al3+ into electrode materials remains an elusive goal. Here, we demonstrate a new strategy to achieve reversible Mg2+ and Al3+ insertion in anatase TiO2, achieved through aliovalent doping, to introduce a large number of titanium vacancies that act as intercalation sites. We present a broad range of experimental and theoretical characterizations that show a preferential insertion of multivalent ions into titanium vacancies, allowing a much greater capacity to be obtained compared to pure TiO2. This result highlights the possibility to use the chemistry of defects to unlock the electrochemical activity of known materials, providing a new strategy for the chemical design of materials for practical multivalent batteries.