MOF derived ZnFe2O4 nanoparticles scattered in hollow octahedra carbon skeleton for advanced lithium-ion batteries

Nanostructure design strategies are highly desired in lithium ion batteries due to the attractive properties of nanosizing. Herein, the hollow octahedra ZnFe2O4@C nanocomposites are synthesized through Zn-Fe MOFs as precursor and used as anode materials for lithium ion batteries. Notably, ZnFe2O4@C nanocomposites possess unique structure, where ZnFe2O4 nanoparticles (similar to 20 nm) well scatters in each surface of the hollow octahedra carbon skeleton (similar to 600 nm) and are also confined by coating carbon. This structure efficiently avoids particle agglomeration, buffers volume expansion, facilitates electron transfer and shortens diffusion lengths. Benefiting from above advantages, ZnFe2O4@C exhibits excellent electrochemical performance, including high specific capacity (1780 mAh g(-1) at 1A g(-1) after 400 cycles), superb rate capability (557 mAh g(-1) at 15 A g(-1)) and ultralong cycling stability (918 mAh g(-1) at 3 A g(-1) after 800 cycles). As much, this work may develop an effective nanostructure aiding in designing a variety of metal oxide/carbon composites of interest for energy storage applications.