Engineering honeycomb-like carbon nanosheets encapsulated iron chalcogenides: Superior cyclability and rate capability for sodium ion half/full batteries

Abstract

Metal chalcogenide-based anodes have attracted extraordinary attention for rechargeable sodium-ion batteries (SIBs) due to their cost-effectiveness and relatively high theoretical capacities. However, they usually exhibit poor electrochemical performance due to large volume change and low ionic/electronic conductivity. Herein, an effective strategy is developed to fabricate nitrogen doping 3D honeycomb-like carbon nanosheets-wrapped FeS nanoparticles for SIB anodes with outstanding sodium storage performance. As a result, FeS@NC anode exhibits high sodium ion storage capacity of 666.0 mAh g−1 at a current density of 0.1 A g−1, excellent rate capability of 617.3 mAh g−1 at 2 A g−1 and superior cycling stability. Moreover, the FeS@NC anode in a full-cell configuration shows high cyclic stability (no capacity attenuation over 200 cycles with 99.9% coulombic efficiency). Accordingly, this work provides a new avenue to construct high-performance anode materials for SIBs.