Facile and scalable synthesis of α -Fe ₂ O ₃ / γ -Fe ₂ O ₃ /Fe/C nanocomposite as advanced anode materials for lithium/sodium ion batteries

Abstract

Abstract To develop low-cost advanced anode materials for lithium/sodium ion batteries, the chemical reaction equilibrium of Fe(NO 3 ) 3 and glucose in hot aqueous solution is creatively used to fabricate a new α -Fe 2 O 3 / γ -Fe 2 O 3 /Fe/C nanocomposite with the primary particle sizes concentrated at 25–80 nm. As anodes for lithium ion batteries, it exhibits a discharge capacity of ∼878 mAh g −1 after 200 cycles at a current density of 200 mA g −1 . Moreover, even after 1000 cycles at a current density of 3200 mA g −1 , the discharge capacity is as high as ∼532 mAh g −1 , with a capacity retention of over than 100% against that of the second cycle. As anodes for sodium ion batteries, the nanocomposite displays a stable discharge capacity of ∼400 mAh g −1 at a current density of 100 mA g −1 and no obvious capacity degradation happens after 200 cycles. During cycling, the α -Fe 2 O 3 / γ -Fe 2 O 3 /Fe/C nanocomposite electrodes shows high structural stability and relatively faster reaction kinetics, which should be responsible for its excellent electrochemical performance. This work provides a facile and scalable route to synthesize high-performance and low-cost Fe 2 O 3 -based nanocomposite for the secondary batteries.