Constructing a mesoporous carbon incorporated FeF3 nanocomposite cathode by one-step impregnation route for Li-ion battery applications

Abstract

The development of cathode materials for lithium-ion batteries (LIBs) has become extremely important and has received much attention in recent years. Iron trifluorides (FeF₃) are of great interest as cathode materials because of their low cost, low toxicity, earth-abundance, eco-friendly nature, and high theoretical capacity. In the present study, we report that mesoporous carbon incorporated FeF₃ nanocomposite has been successfully synthesized by a simple sol–gel method followed by heat treatment. The phase structures, surface area, and surface morphologies of the mesoporous carbon incorporated FeF₃ nanocomposite were investigated and confirmed through various characterization techniques. The morphological characterization reveals the formation of a rectangular-shaped morphology with mesoporous pores with an average size of ∼10 nm. Furthermore, the mesoporous carbon incorporated FeF₃ nanocomposite material was used as a cathode material for LIBs, with enhanced electrochemical performance which delivered initial discharge capacities of 325 mA h g⁻¹ in the voltage range of 1.5–4.5 V and 180 mA h g⁻¹ in the range of 2.0–4.5 V, compared the discharge capacity of 140 mA h g⁻¹ for bare FeF₃ at a rate of 0.1C. Moreover, it displayed stable capacity retention, cycle life, and rate capability. Furthermore, the improved electrochemical performance can be attributed to the good electrical conductivity, mesoporous structure, and high surface area, which significantly facilitate fast Li-ion diffusion and Li insertion/extraction kinetics.