Nanosheet assembled hollow ZnFe2O4 microsphere as anode for lithium-ion batteries

Nanosheet assembled hollow ZnFe2O4 microspheres have been successfully prepared using a general hydrothermal method together with post-annealed process. As the anode electrode of a lithium-ion battery, the high discharge capacity of 1200 mAh g−1 can be obtained after 120 cycles at a current density of 100 mA g−1. It is noted that the cell capacity still remains at 533 mAh g−1 after 250 cycles at a high current density of 500 mA g−1. The prominent electrochemical performance is related to the unique mesoporous hollow structure, which increases the contact areas of the electrolyte and active material resulting in well electrolyte permeation as well as providing abundant void space to suppress the volume expansion during the lithium-ion insertion and extraction process.