Synthesis of nitrogen-doped porous carbon nanofibers as an anode material for high performance sodium-ion batteries

Abstract

Novel nitrogen-doped porous carbon nanofibers (NP-CNFs) were prepared by carbonization of the CNFs@polydopamine composite. The NP-CNFs were served as the anode material for sodium-ion batteries, showing a superior reversible discharge capacity of 174 mAh g−1 after 300 cycles at the current density of 50 mA g−1. Even at a high current density of 2 A g−1, a high reversible discharge capacity of 103 mAh g−1 can also be attained. Besides, even in the case of 500 mA g−1, this work also observes the prominent cycling stability in the long term (>1200 cycles). These results suggest that the NP-CNFs electrode shows prominent electrochemical performance. Such prominent electrochemical performance of NP-CNFs electrode may be attributed to the synergetic effect between the nitrogen-doping and the porous structure. The capacity can be greatly increased by the nitrogen-doping, and the porous structured NP-CNFs can be sufficiently contacted with the electrolyte and promote the sodium ion/electrons transportation.