Carbon modified porous γ-Fe₂O₃ as anode for high performance Li-ion batteries

Carbon modified porous γ-Fe₂O₃ particles (PFe₂O₃–C) are synthesized by a high temperature calcination method using sodium chloride as a template. During the nucleation and carbonation process, the Fe(NO₃)₃–C₁₀H₁₅N₅ complex uniformly dispersed on the surface of NaCl particles which can limit its longitudinal growth, thus forming independent and homogeneous nanoparticles with a diameter of about 30 nm. Because of this special structure, the γ-Fe₂O₃ particles have a sufficient interspace between them, which can not only provide a large number of active sites for storing lithium ions, but also shorten diffusion length for lithium ion transport. The introduction of carbon can offer additional lithium ion storage and improve overall electrical conductivity. This PFe₂O₃–C electrode exhibits excellent rate performance (1139, 1067, and 972 mAh g⁻¹ at 2, 5, and 10 C, respectively, 1 C = 924 mAh g⁻¹) and cycle performance (up to 2100 mAh g⁻¹ after 200 cycles at 0.3 C).