Ultrahigh level nitrogen/sulfur co-doped carbon as high performance anode materials for lithium-ion batteries

Abstract

Ultrahigh level nitrogen and sulfur co-doped disordered porous carbon (NSDPC) was facilely synthesized and applied as anode materials for lithium-ion batteries (LIBs). Benefiting from high nitrogen (14.0 wt%) and sulfur (21.1 wt%) doping, electrode fabricated from NS1/3 showed a high reversible capacity of 1188 mA h g−1 at 0.1 A g−1 in the first cycle with a high initial columbic efficiency (>75%). In addition, prolonged life over 500 cycles and excellent rate capability of 463 mA h g−1 at 5 A g−1 have been realized. The preeminent electrochemical performance is attributed to three effects: (1) the high level of sulfur and nitrogen; (2) the synergic effect of dual-doping heteroatoms in cooperation with each other; (3) the large quantity of edge defects and abundant micropores and mesopores that can provide extra Li storage regions. These unique features of NSDPC electrodes suggest that they can serve as a practical substitute for graphite as a high performance anode material in LIBs.