Solution Synthesis of Porous Silicon Particles as an Anode Material for Lithium Ion Batteries

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 HSiCl₃ 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⁻¹ after 200 cycles at 1 A g⁻¹ and a discharge capacity of 750 mA h g⁻¹ at a current density of 2 A g⁻¹ after 250 cycles. Remarkably, the Coulombic efficiency was maintained at nearly 100 % throughout the measurements.