Wintersweet-Flower-Like CoFe2O4/MWCNTs Hybrid Material for High-Capacity Reversible Lithium Storage

Abstract

CoFe2O4/multiwalled carbon nanotubes (MWCNTs) hybrid materials were synthesized by a hydrothermal method. Field emission scanning electron microscopy and transmission electron microscopy analysis confirmed the morphology of the as-prepared hybrid material resembling wintersweet flower buds on branches, in which CoFe2O4 nanoclusters, consisting of nanocrystals with a size of 510 nm, are anchored along carbon nanotubes. When applied as an anode material in lithium ion batteries, the CoFe2O4/MWCNTs hybrid material exhibited a high performance for reversible lithium storage. In particular, the hybrid anode material delivered reversible lithium storage capacities of 809, 765, 539, and 359 mA?h?g-1 at current densities of 180, 450, 900, and 1800 mA?g-1, respectively. The superior performance of CoFe2O4/MWCNTs hybrid materials could be ascribed to the synergistic pinning effect of the wintersweet-flower-like nanoarchitecture. This strategy could also be applied to synthesize other metal oxide/CNTs hybrid materials as high-capacity anode materials for lithium ion batteries.