Sorbonne Université, CNRS, Physico-chimie des électrolytes et nano-systèmes interfaciaux, PHENIX, Paris F-75005, France.
Chem Commun (Camb). 2018 Sep 6;54(72):10080-10083. doi: 10.1039/c8cc04136a.
In anatase TiO2, substituting oxide anions with singly charged (F,OH) anions allows the controlled formation of cation vacancies, which act as reversible intercalation sites for Mg2+. We show that ion-transport (diffusion coefficients) and intercalation (reversible capacity) properties are controlled by two critical parameters: the vacancy concentration and the local anionic environment. Our results emphasise the complexity of this behaviour, and highlight the potential benefits of chemically controlling cationic-defects in electrode materials for rechargeable multivalent-ion batteries.
在锐钛矿 TiO2 中，用单价（F、OH）阴离子取代氧化物阴离子可以控制阳离子空位的形成，阳离子空位可作为 Mg2+的可逆嵌入位点。我们表明，离子输运（扩散系数）和嵌入（可逆容量）性能由两个关键参数控制：空位浓度和局部阴离子环境。我们的研究结果强调了这种行为的复杂性，并突出了在可充电多价离子电池中通过化学控制电极材料中阳离子缺陷的潜在优势。
