C/TiO2 Double-Coated Porous Fe3O4 as a High Mechanical Stress Anode Material for Lithium-Ion Batteries

In the course of charge and discharge cycles, the anode based on Fe₃O₄ tends to undergo volume expansion, leading to significant degradation in battery performance. To overcome this issue, a strategy involving pore formation and co-coating with carbonaceous materials and TiO₂ was employed. Initially, a hard template method was used to synthesize multilevel porous Fe₃O₄, utilizing glucose and urea as pore-forming agents. Subsequently, carbon coating was applied to the multilevel porous Fe₃O₄ using an aldehyde resin. Finally, the carbon-coated porous Fe₃O₄ was further coated with TiO₂, and the TiO₂ coating was hydrogenated to enhance its conductivity. The results demonstrated that the presence of multilevel pores, along with the dual coating of carbon and TiO₂, significantly reduced the volumetric expansion of the H-TiO₂-C-Fe₃O₄ electrode material during the charge and discharge cycles. At a current density of 0.2 A g⁻¹, the H-TiO₂-C-Fe₃O₄ electrode showed a discharge capacity of 599.61 mA h g⁻¹ after 500 cycles. Furthermore, at a current density of 1 A g⁻¹, the discharge capacity was 542.64 mA h g⁻¹ after 700 cycles. The excellent rate performance of the H-TiO₂-C-Fe₃O₄ electrode highlights its potential for application in high-current batteries.