Active Fe2O3 nanoparticles encapsulated in porous g-C3N4/graphene sandwich-type nanosheets as a superior anode for high-performance lithium-ion batteries

Abstract

Designing sandwich-like hybrid nanosheets with a porous structure effectively improves the electrochemical performance of graphene-based materials in lithium-ion batteries (LIBs) owing to the mitigated restack of graphene and decreased diffusion distance of Li⁺ ions for electron storage. Herein, a novel composite of active Fe₂O₃ nanoparticles encapsulated in g-C₃N₄/graphene hybrid nanosheets (Fe₂O₃/CN–G) has been developed, in which the 2D sandwich-type hybrid nanosheets constructed using porous g-C₃N₄ and highly conductive graphene offer readily accessible channels and sufficient conductive pathways for ionic diffusion and charge transport. This unique architecture greatly inhibits the restacking or aggregation of graphene and ensures the stability of electro-active Fe₂O₃ nanoparticles. Benefiting from these intriguing features, the as-prepared Fe₂O₃/CN–G as an anode for LIBs shows excellent electrochemical behaviors, including considerably large reversible capacity (1023 mA h g⁻¹), great coulombic efficiency (97.6%), strong durability and comparable rate performance. Therefore, the work described here can provide a new insight for designing high-performance electrode materials with a porous and sandwich-type hybrid structure for application in LIBs.