State Key Laboratory of Silicon Materials, Key Laboratory of Novel Materials for Information Technology of Zhejiang Province and School of Materials Science & Engineering, Zhejiang University , Hangzhou, Zhejiang 310027, P. R. China.
Department of Materials Science & Engineering, Xiamen University , Xiamen 361005, P. R. China.
ACS Appl Mater Interfaces. 2017 Jul 12;9(27):22369-22377. doi: 10.1021/acsami.7b02385. Epub 2017 Jun 27.
Rechargeable sodium-ion batteries (SIBs) are receiving intense interest because the resource abundance of sodium and its lithium-like chemistry make them low cost alternatives to the prevailing lithium-ion batteries in large-scale energy storage devices. Two typical classes of materials including transition metal oxides and polyanion compounds have been under intensive investigation as cathodes for SIBs; however, they are still limited to poor stability or low capacity of the state-of-art. Herein, we report a low cost carbon-coated NaFeSiO with simultaneous high capacity and good stability, owing to the highly pure Na-rich triclinic phase and the carbon-incorporated three-dimensional network morphology. The present carbon-coated NaFeSiO demonstrates the highest reversible capacity of 181.0 mAh g to date with multielectron redox reaction that occurred among various polyanion-based SIBs cathodes, which achieves a close-to-100% initial Coulombic efficiency and a stable cycling with 88% capacity retention up to 100 cycles. In addition, such an electrode shows excellent stability either charged at a high voltage of 4.5 V or heated up to 800 °C. The present work might open up the possibility for developing high capacity, good safety and low cost polyanion-based cathodes for rechargeable SIBs.
可充电钠离子电池（SIBs）受到了广泛关注，因为钠的资源丰富及其类似锂离子的化学性质使得它们成为大规模储能设备中现有锂离子电池的低成本替代品。两种典型的材料类别，包括过渡金属氧化物和聚阴离子化合物，一直被作为 SIBs 的正极材料进行深入研究；然而，它们仍然受到较差的稳定性或低容量的限制。在此，我们报道了一种低成本的碳包覆 NaFeSiO，它具有高容量和良好的稳定性，这归因于高度纯净的富钠三方相和碳掺入的三维网络形态。目前的碳包覆 NaFeSiO 表现出迄今为止最高的可逆容量 181.0 mAh g，具有多种多阴离子基 SIBs 正极材料之间的多电子氧化还原反应，初始库仑效率接近 100%，在 100 次循环中具有 88%的稳定循环容量保持率。此外，该电极在充电至 4.5 V 的高电压或加热至 800°C 时都表现出优异的稳定性。本工作可能为开发高容量、良好安全性和低成本的多阴离子基可充电 SIBs 正极材料开辟了可能性。
