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

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.