Wang Fei, Sun Lin, Zi Wenwen, Zhao Baoxun, Du Hongbin
State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China.
School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng, 224051, P. R. China.
Chemistry. 2019 Jul 5;25(38):9071-9077. doi: 10.1002/chem.201901238. Epub 2019 Jun 11.
Nanostructured silicon-based materials with porous structures have recently been found to be impressive anode materials with high capacity and cycling performance for lithium-ion batteries. However, the current methods of preparing porous silicon have generally been confronted with the requirement for multiple steps and complex synthesis. In the present study, porous silicon with high surface area was prepared by using a high yielding and simple reaction in which commercial magnesium powder readily reacts with HSiCl with the help of an amine catalyst under mild conditions. The obtained porous silicon was coated with a nitrogen-doped carbon layer and used as the anode for lithium-ion batteries. The porous Si-carbon nanocomposites exhibited excellent cycling performance with a retained discharge capacity of 1300 mA h g after 200 cycles at 1 A g and a discharge capacity of 750 mA h g at a current density of 2 A g after 250 cycles. Remarkably, the Coulombic efficiency was maintained at nearly 100 % throughout the measurements.
最近发现，具有多孔结构的纳米结构硅基材料是用于锂离子电池的具有高容量和循环性能的令人印象深刻的负极材料。然而，目前制备多孔硅的方法通常面临多步骤和复杂合成的要求。在本研究中，通过使用高产率且简单的反应制备了具有高表面积的多孔硅，在温和条件下，商业镁粉在胺催化剂的帮助下容易与HSiCl反应。将所得的多孔硅涂覆有氮掺杂碳层并用作锂离子电池的负极。多孔硅-碳纳米复合材料表现出优异的循环性能，在1 A g下循环200次后保留的放电容量为1300 mA h g，在250次循环后在2 A g的电流密度下放电容量为750 mA h g。值得注意的是，在整个测量过程中库仑效率保持在近100％。
