One-pot Synthesis of Nano-NiFe₂O₄ Pinning on the Surface of the Graphite Composite as Superior Anodes for Li-ion Batteries

Nickel ferrite and related materials have recently received considerable attention as potential anode in lithium-ion batteries for their high theoretical specific capacities. To overcome low intrinsic electronic conductivity and large volume expansion during the Li insertion/extraction process, in this work, nano-NiFe₂O₄ pinning on the surface of the graphite composite was prepared by a hydrothermal method. As the superior anode material, the as-obtained nano-NiFe₂O₄/graphite composite demonstrates high capacity and excellent cycle stability. An initial specific discharge capacity of approximate 1478 mAh·g^-1 and a reversible specific capacity of approximate 1109 mAh·g^-1 after 50 cycles at a current density of 100 mA·g^-1 are reached. When the charging current is increased to 1000 mA·g^-1, it also delivers a charge capacity of 750 mAh·g^-1. The excellent performances are attributed to the special structure of NiFe₂O₄ nanoparticles pinning on the surface of the graphite, especially the enhanced electronic conductivity and area specific capacitance during the cycling process.