Graphene‐Oxide‐Encapsulated Fe₂O₃ Nanoparticles with Different Dimensions as Lithium‐Ion Battery Anodes: The Morphology Effect of Fe₂O₃

Abstract

Fe 2 O 3 is expected to be a favorable candidate to replace commercial graphite as anode for lithium-ion batteries (LIBs), however, it is impeded by dramatic volume expansion during charge/discharge process. Morphology control strategies have been widely conducted to develop the tolerance of Fe 2 O 3 against the volume change. To investigate the morphology effect, herein, graphene oxide (GO) encapsulated Fe 2 O 3 nanoparticles with three microstructures of nano-rods, nano-sheets, nano-polyhedrons were synthesized. The structure-dependent electrochemical performance has been demonstrated. The 1D rod-like nano-Fe 2 O 3 alleviates the inherent wrinkle morphology of GO sheets, which construct a stable three-dimensional composite structure. Therefore, the GO-encapsulated rodshaped Fe 2 O 3 (Fe/GO-r) exhibits excellent reversible capacity of 1168.3 mA h g À 1 over 100 cycles at 200 mA g À 1 . The investigation of lithium-ion migration kinetics indicates that Fe/GO-r presents the highest contribution rate of surface induced capacitance. This study contributes towards the design of wellperforming anode materials for LIBs by investigating the effect of material morphologies.