Facile solution-free preparation of a carbon coated Fe3O4 nanoparticles/expanded graphite composite with outstanding Li-storage performances

A novel carbon coated Fe3O4 nanoparticles (NPs)/expanded graphite (EG) composite has been prepared by in-situ pyrolysis of ferrecene on the nanosheets (NSs) of EG in an isolated atmosphere. Results indicated that the restack behavior of the NSs of EG which is easy to be induced by solvent removal was effectively avoided by this solution-free route. Well-crystallized Fe3O4-NPs with a dimension of <5 nm were observed to be homogeneously anchored on these NSs. The composite as anode material of Li-ion batteries (LIBs) exhibited prominently enhanced reversible capacity and rate capability, meanwhile inherited the superior cycling performance of EG. After 100 cycles at 100 mA g−1, the charge capacity still reached 728 mA h g−1, which was 283% higher than that of pure EG. The greatly improved electrochemical performances are ascribed to the favorable synergistic effect between carbon coated Fe3O4-NPs and EG, suggesting that the special Fe3O4-NPs/EG composite is promising anode material for high-performance LIBs.