A three-dimensional silicon/nitrogen-doped graphitized carbon composite as high-performance anode material for lithium ion batteries

The three-dimensional conductive skeleton plays an important role for silicon-based anode materials to achieve good electrochemical performance in lithium ion batteries with high energy density. Here, we prepared a three-dimensional silicon/N-doped graphitized carbon composite (3D Si/NGC) from ZIF-67 precursor by magnesiothermic reduction reaction. The N-doped and graphitized conductive carbon acts as a robust three-dimensional configuration for the silicon nanoparticles, not only improving the conductivity of electrode, but also buffering the volume expansion of silicon nanoparticles. The 3D Si/NGC electrode exhibits good long-term cycle stability and impressive rate performance, delivering reversible capacity of 900 mA h g⁻¹ at 0.2 A g⁻¹ after 300 cycles with a capacity retention of 85.5% and a high discharge capacity of 880 mA h g⁻¹ at 1 A g⁻¹. The 3D Si/NGC with good electrochemical performance shows great potential as the next generation anode material for lithium ion batteries.