Plate-like carbon-supported Fe₃C nanoparticles with superior electrochemical performance

Abstract: Iron-based anodes for lithium-ion batteries (LIBs) with higher theoretical capacity, natural abundance and cheapness have received considerable attention, but they still suffer from the fast capacity fading. To address this issue, we report a facile synthesis of plate-like carbon-supported Fe₃C nanoparticles through chemical blowing/carbonization under calcination. The ultrafine Fe₃C nanoparticles are prone to be oxidized when exposing in air; thus, Fe₃C/C with mild oxidization and the fully oxidized product of Fe₂O₃/C are successfully prepared by controlling the oxidization condition. When applied as an anode material in LIB, the Fe₃C/C electrode demonstrates excellent cycle stability (826 mAh·g⁻¹ after 120 cycles under 500 mA·g⁻¹) and rate performance (410.6 mAh·g⁻¹ under 2 A·g⁻¹), compared with the Fe₂O₃/C counterpart. The enhanced electrochemical performance can be ascribed to the synergetic effect of the Fe₃C with mild oxidation and the unique hierarchical structure of plate-like carbon decorated with Fe₃C catalyst. More importantly, this work may offer new approaches to synthesize other transition metal (e.g., Co, Ni)-based anode material by replacing the precursor ingredient. Graphic abstract: [Figure not available: see fulltext.]