School of Materials Science & Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, P.R. China.
Collaborative Innovation Center of Electric Vehicles in Beijing , Beijing 100081, P.R. China.
ACS Appl Mater Interfaces. 2016 Jun 29;8(25):16078-86. doi: 10.1021/acsami.6b04151. Epub 2016 Jun 14.
Traditional Prussian blue (Fe4[Fe(CN)6]3) synthesized by simple rapid precipitation shows poor electrochemical performance because of the presence of vacancies occupied by coordinated water. When the precipitation rate is reduced and polyvinylpyrrolidone K-30 is added as a surface active agent, the as-prepared Prussian blue has fewer vacancies in the crystal structure than in that of traditional Prussian blue. It has a well-defined face-centered-cubic structure, which can provide large channels for Na(+) insertion/extraction. The material, synthesized by slow precipitation, has an initial discharge capacity of 113 mA h g(-1) and maintains 93 mA h g(-1) under a current density of 50 mA g(-1) after 150 charge-discharge cycles. After further optimization by a chemical etching method, the complex nanoporous structure of Prussian blue has a high Brunauer-Emmett-Teller surface area and a stable structure to achieve high specific capacity and long cycle life. Surprisingly, the electrode shows an initial discharge capacity of 115 mA h g(-1) and a Coulombic efficiency of approximately 100% with capacity retention of 96% after 150 cycles. Experimental results show that Prussian blue can also be used as a cathode for Na-ion batteries.
传统普鲁士蓝（Fe4[Fe(CN)6]3）通过简单快速沉淀合成，由于存在被配位水占据的空位，因此电化学性能较差。当沉淀速率降低并添加聚乙烯吡咯烷酮 K-30 作为表面活性剂时，所制备的普鲁士蓝在晶体结构中具有比传统普鲁士蓝更少的空位。它具有明确的面心立方结构，可以为 Na(+) 的插入/提取提供大通道。该材料通过缓慢沉淀合成，在 50 mA g(-1)的电流密度下经过 150 次充放电循环后，初始放电容量为 113 mA h g(-1)，并保持 93 mA h g(-1)。通过化学刻蚀方法进一步优化后，普鲁士蓝的复杂纳米多孔结构具有高 Brunauer-Emmett-Teller 比表面积和稳定的结构，可实现高比容量和长循环寿命。令人惊讶的是，该电极在 150 次循环后具有 115 mA h g(-1)的初始放电容量和接近 100%的库仑效率，容量保持率为 96%。实验结果表明，普鲁士蓝也可用作钠离子电池的阴极。
