Microwave-assisted and gram-scale synthesis of ultrathin SnO2 nanosheets with enhanced lithium storage properties.
Microwave-assisted and gram-scale synthesis of ultrathin SnO2 nanosheets with enhanced lithium storage properties.
复制标题
DOI：
10.1021/am507826d
复制
发表时间：
2015-01
影响因子：
9.5
通讯作者：
Youqi Zhu;Huizi Guo;H. Zhai;C. Cao
中科院分区：
文献类型：
--
作者：
Youqi Zhu;Huizi Guo;H. Zhai;C. Cao
合理的SnO2基负极材料的设计和制备可以有效地缓解其体积变化大的问题，为电化学储锂提供良好的反应动力学保证。在这里，我们提出了一种超快速、低成本、简单的克级微波辅助合成超薄SnO2纳米片的方法。二维各向异性生长依赖于微波介质辐照和表面活性剂结构方向的耦合，是在低温大气条件下进行的。超薄的2D纳米结构具有很高的表面锡原子百分比和高活性，可以促进高度依赖于表面的电化学反应过程。与一维SnO2纳米棒相比，超薄SnO2纳米棒具有显著的电化学储锂性能，在200mAg(-1)的电流密度下循环40次，其可逆容量高达757.6 mAHg(-1)，并具有优异的倍率性能和循环稳定性。具体地说，超薄的2D纳米片可以显著减少离子扩散路径，从而允许更快的相变，而充足的外部表面间隙和内部多孔结构可以成功地适应巨大的体积变化。更重要的是，我们开发了一种有希望的策略来生产超薄的SnO2纳米片，以解决其商业应用的内在问题。
The rational design and fabrication of SnO2-based anode materials could offer a powerful way of effectively alleviating their large volume variation and guaranteeing excellent reaction kinetics for electrochemical lithium storage. Herein, we present an ultrarapid, low-cost, and simple microwave-assisted synthesis of ultrathin SnO2 nanosheets at the gram-scale. The two-dimensional (2D) anisotropic growth depends on microwave dielectric irradiation coupled with surfactant structural direction, and is conducted under low-temperature atmospheric conditions. The ultrathin 2D nanostructure holds a great surface tin atom percentage with high activity, where the electrochemical reaction processes could be facilitated that highly dependent on the surface. Compared with 1D SnO2 nanorods, the ultrathin SnO2 nanosheets exhibit remarkably improved electrochemical lithium storage properties with a high reversible capacity of 757.6 mAh g(-1) at a current density of 200 mA g(-1) up to 40 cycles as well as excellent rate capability and cycling stability. Specifically, the ultrathin 2D nanosheet could significantly reduce ion diffusion paths, thus allowing faster phase transitions, while the sufficient external surface interspace and interior porous configuration could successfully accommodate the huge volume changes. Even more importantly, we develop a promising strategy to produce ultrathin SnO2 nanosheets to tackle their intrinsic problems for commercial applications.