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

Fe2O3 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 Fe2O3 against the volume change. To investigate the morphology effect, herein, graphene oxide (GO) encapsulated Fe2O3 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-Fe2O3 alleviates the inherent wrinkle morphology of GO sheets, which construct a stable three-dimensional composite structure. Therefore, the GO-encapsulated rod-shaped Fe2O3 (Fe/GO-r) exhibits excellent reversible capacity of 1168.3 mA h g(-1) over 100 cycles at 200 mA g(-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 well-performing anode materials for LIBs by investigating the effect of material morphologies.

Automated summary

This study investigates the effect of morphology on the electrochemical performance of Fe2O3 by synthesizing graphene oxide (GO) encapsulated Fe2O3 nanoparticles with three different microstructures. The rod-shaped Fe2O3 exhibits excellent reversible capacity and surface induced capacitance contribution rate, providing insights for the design of high-performance LIB anode materials.