Electrochemical performance of porous CaFe₂O₄ as a promising anode material for lithium-ion batteries

The performance of existing lithium-ion batteries (LIBs) is greatly hindered by the low specific capacity of graphite-based anodes (372 mAh g⁻¹). Therefore, development of suitable anode materials that exhibit higher and stable capacity is necessary to improve performance. Transition metal oxides have attracted tremendous attention as next-generation anode materials for LIBs due to their high theoretical capacity. Herein, we report the synthesis of a porous CaFe₂O₄ by a facile and time efficient solution combustion synthesis technique for use in an anode for LIBs. The as-prepared material exhibited improved electrochemical performance with specific discharge capacities of 441 mAh g⁻¹, 518 mAh g⁻¹, and 516 mAh g⁻¹ for the initial three cycles. It achieved stability with a deliverable specific discharge capacity of 551 mAh g⁻¹ after 150 cycles at a current density of 200 mA g⁻¹. The porous CaFe₂O₄ exhibits improved cyclic performance and rate capability. These improvements are attributed to the porous nature of active material and, more importantly, the presence of CaO, which effectively alleviates the volume changes by acting as a buffer matrix.