Core-Shell NiFe_2O_4@TiO_2 Nanorods: An Anode Material with Enhanced Electrochemical Performance for Lithium-Ion Batteries

摘要

Hierarchical porous core-shell NiFe_2O_4@TiO_2 nanorods have been fabricated with the help of hydrothermal synthesis, chemical bath deposition, and a subsequent calcinating process. The nanorods with an average diameter of 48 nm and length of about 300-600 nm turn out have a highly uniform morphology and are composed of nanosized primary particles. Owing to the synergistic effect of individual constituents as well as the hierarchical porous structure, the novel core-shell NiFe_2O_4@TiO_2 nanorods exhibit superior electrochemical performance when evaluated as anode materials for lithium-ion batteries. At the current density of 100 mAg~(-1), the composite exhibits a reversible specific capacity of 1034 mAhg~(-1) up to 100 charge-discharge cycles, which is much higher than the uncoated NiFe_2O_4 nanorods. Even when cycled at 2000 mAg~(-1), the discharge capacity could still be maintained at 358 mAhg~(-1).