Na2Ti3O7纳米片原位制备与钠离子电池负极材料应用

报道了Na₂Ti₃O₇纳米片的原位生长和钠离子电池负极材料的应用。通过简单的腐蚀市售的钛片制备出相互连接的微纳结构的Na₂Ti₃O₇纳米片。此外，腐蚀后的钛片在不用添加导电剂或粘结剂的情况下，可以直接作为电极材料使用。这种电极材料表现出优越的电化学性能，在50 mA·g^–1的电流密度下具有175 mAh·g^–1的可逆容量，在2000 mA·g^–1的电流密度下循环3000周后，其容量仍保持120 mAh·g^–1，容量保持率为96.5%。Na₂Ti₃O₇纳米片电极的优越电化学性能归因于二维结构具有较短的离子/电子扩散路径以及无粘结剂结构能有效的增加电极的电子传导能力。结果表明，这种微纳结构能够有效地克服Na₂Ti₃O₇作为电极材料离子/电子导电性差的缺点。因此，这种无粘结剂结构的Na₂Ti₃O₇纳米片负极材料是一种很有潜力的钠离子负极材料。

In-situ Preparation of Na2Ti3O7 Nanosheets as High-Performance Anodes for Sodium Ion Batteries

We report on the in-situ preparation of Na₂Ti₃O₇ nanosheets and their application as high-performance anode material for sodium ion batteries. Nanosheets with interconnected micro-nano architectures are prepared by simply engraving commercial titanium foils. Furthermore, the foils can be used directly as electrodes without redundant conductive additives or binders. The electrode material exhibits excellent electrochemical performance with reversible capacity of 175 mAh·g^–1 at 50 mA·g^–1 and 120 mAh·g^–1 at 2000 mA·g^–1 after 3000 cycles (capacity retention of 96.5%). The superior electrochemical performance of Na₂Ti₃O₇ nanosheets results from the short ion/electron diffusion pathway of the two-dimensional architecture and the good conductive capability of the binder-free structure. The anode of the binder-free Na₂Ti₃O₇ nanosheets effectively overcomes poor ion/electron conductivity, the main drawback of Na₂Ti₃O₇ electrodes, and is promising for rechargeable sodium ion batteries.