In situ synthesis of hierarchical mesoporous Fe3O4@C nanowires derived from coordination polymers for high-performance lithium-ion batteries

Abstract

A facile two-step strategy is developed for in situ fabrication of hierarchical nanostructured Fe₃O₄@C mesoporous nanowires. Coordination polymers that served as a precursor and self-template are hydrothermally synthesized in the first step, and subsequently thermally treated in an inert atmosphere. Well-defined mesoporous nanowires that are assembled from a large number of core–shell structured Fe₃O₄@C spherical particles with an ultrasmall and uniform size (∼8 nm) are successfully obtained. As a proof-of-concept application, they are used as anode materials for lithium-ion batteries. These Fe₃O₄@C mesoporous nanowires exhibit excellent electrochemical performance with high reversible capacity, good cycling stability and rate capability. The remarkable electrochemical performance is due to the effective combination of ultrasmall and uniform Fe₃O₄ nanoparticles, mesoporous nanowire structures and carbon networks, which simultaneously supply a high contact area, mitigate the volume change during the lithiation/delithiation process, and enhance the electronic conductivity.