Seeding Iron Trifluoride Nanoparticles on Reduced Graphite Oxide for Lithium-Ion Batteries with Enhanced Loading and Stability

Abstract

Development of electric vehicles and portable electronic devices during the past decade calls for lithium-ion batteries (LIBs) with enhanced energy density and higher stability. Integration of FeF₃ phases and carbon structures leads to promising cathode materials for LIBs with high voltage, capacity, and power. In this study, FeF₃·0.33H₂O nanoparticles were synthesized on reduced graphite oxide (rGO) nanosheets using an in situ approach. By chemically tuning the interfacial bonding between FeF₃·0.33H₂O and rGO, we successfully achieved high particle loading and enhanced cycling stability. Specifically, a discharge capacity of ∼208.3 mAh g^-1 was observed at a current density of 0.5 C. The FeF₃·0.33H₂O/rGO nanocomposites also demonstrate great cycle capability with a reversible discharge capacity of 133.1 mAh g^-1 after 100 cycles at 100 mA g^-1; the capacity retention is about 97%. This study provides an alternative strategy to further improve the stability and performance of iron fluoride/carbon nanocomposite materials for LIB applications.