Core/shell Fe3O4@Fe encapsulated in N-doped three-dimensional carbon architecture as anode material for lithium-ion batteries

Core-shell Fe 3 O 4 @Fe nanoparticles embedded into porous N-doped carbon nanosheets was prepared by a facile method with NaCl as hard-template. The three-dimensional carbon architecture built by carbon nanosheets enhance the conductivity of the encapsulated Fe 3 O 4 @Fe nanoparticles and strengthen the structure stability suffering from volume expansion during extraction and insertion of lithium ions . Rich Pores enhance the surface between electrode and electrolyte, which short the transmission path of ions and electrons. The core-shell structure with Fe as core further improves charge transferring inside particles thus lead to high capacity. The as-prepared Fe 3 O 4 @Fe/NC composite displays an irreversible discharge capacity of 839 mAh g −1 at 1 A g −1 , long cycling life (722.2 mAh g −1 after 500th cycle at 2 A g −1 ) and excellent rate performance (1164.2 and 649.2 mAh g −1 at 1 and 20 A g −1 , respectively). The outstanding electrochemical performance of the Fe 3 O 4 @Fe/NC composite indicates its application potential as anode material for LIBs .