Si nanoparticles adhering to a nitrogen-rich porous carbon framework and its application as a lithium-ion battery anode material

Abstract

In this work, a novel Si/nitrogen-rich porous C composite was prepared by the simple co-assembly of gelatin, nano-CaCO₃ particles and Si nanoparticles, followed by a pyrolysis process and a subsequent acid washing treatment to remove the template. The Si nanoparticles adhered to the nitrogen-rich porous carbon framework, which possesses good conductivity and adequate free space to accommodate the volume change of Si nanoparticles during cycling. In contrast with the bare Si nanoparticles and the conventional Si/C composite, the electrochemical performance of the as-prepared Si/nitrogen-rich porous C composite has been improved significantly. It delivers a reversible capacity of 1103 mA h g⁻¹ after 100 cycles at a current density of 100 mA g⁻¹ and 766 mA h g⁻¹ at 2 A g⁻¹, much higher than those of commercial graphite anodes. In addition, the synthesis method can be easily scaled up and widely applied to other high-capacity anode and cathode material systems that undergo large volume expansion.