One-pot in-situ synthesis of nano-Fe₃C decorated N, S co-doped carbon nanotubes as anode material for high performance lithium-ion batteries

Iron carbide (Fe₃C) has become a significant type of anode material for lithium-ion batteries (LIBs) due to its intrinsic catalytic ability for the reversion of solid electrolyte interface (SEI) film. However, the low electrical conductivity and structural instability still hinder its practical application. The combination of Fe₃C with highly conductive matrix is effective at addressing this issue. In this work, nano-Fe₃C decorated N, S co-doped carbon nanotubes (Fe₃C-NSC) was synthesized through a facile one-pot in-situ growth method. Benefiting from the synergetic effects between nano-Fe₃C and N, S co-doped carbon nanotubes, Fe₃C-NSC demonstrated an ultrahigh reversible capacity of 926 mAh g⁻¹ at 100 mA g⁻¹ after 100 cycles, and maintained a reversible capacity of 510.9 mAh g-1 at 500 mA g⁻¹ after 900 cycles. Even when operated at −20 °C, Fe₃C-NSC still delivered 373.4 mAh g⁻¹ at 100 mA g⁻¹ after 100 cycles. The strategy in this work should provide new insight into Fe₃C-based anode of LIBs.