Self-assembled 3D flower-like Fe₃O₄/C architecture with superior lithium ion storage performance

Fe₃O₄ with a high theoretical specific capacity is a promising anode material for lithium ion batteries (LIBs), but its severe volume variation during the electrochemical process and poor electrical conductivity limit its further applications. To solve these problems, in this work, a self-assembled flower-like Fe₃O₄/C architecture was successfully synthesized via a simple two-step method including a solvo-hydrothermal self-assembly process and a high temperature in situ carbonization process. Field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the morphology, structure and electrochemical performances of the samples, respectively. The flower-like Fe₃O₄/C showed a high discharge capacity of 1165.4 mA h g⁻¹ after 300 cycles at a current density of 277.2 mA g⁻¹ with excellent rate performances. The superior electrochemical performances were triggered primarily due to the incorporation of carbon into the Fe₃O₄ moiety comprising a hollow structure which can offer a high specific surface area and excellent charge transfer ability. The designed flower-like Fe₃O₄/C is a promising anode material for high-performance LIBs.