MOF-derived hollow NiCo2O4 nanowires as stable Li-ion battery anodes
Though binary metals oxides with high theoretical specific capacities and power densities are wildly investigated as promising anode materials for lithium-ion batteries (LIBs), the poor cycling stability and huge volume expansion largely limit their extensive application in practical electrode materials. Herein, we report a facile strategy to synthesize hollow NiCo2O4 nanowires through direct calcination of binary metal-organic frameworks (MOFs) in air. When evaluated as an anode material for LIBs, NiCo2O4 nanowires delivers a reversible capacity of 1310 mAh g-1 at a current density of 100 mA g-1 after 100 cycles. Even at a high current density of 1 A g-1, NiCo2O4 nanowires exhibit long-term cycling stability with capacity of 720 mAh g-1 after 1000 cycles. The outstanding lithium-storage performance can be attributed to the unique structures with 1D porous channels, which is beneficial for the fast transfer for Li+ and electrolyte, and alleviate the strain caused by the volume expansion during cycling processes.