Carbon composite spun fibers with in situ formed multicomponent nanoparticles for a lithium-ion battery anode with enhanced performance.

Carbon composite fibers with Fe₃O₄, Fe₃C, and TiO₂ nanoparticles (Fe₃O₄/Fe₃C/TiO₂/C) were successfully fabricated using a facile dry-spinning approach, followed by annealing under argon flux. When used as the anode material of a lithium-ion battery, the Fe₃O₄/Fe₃C/TiO₂/C composite fibers achieved a reversible capacity of 702.1 mA h g⁻¹ after 400 cycles at a current density of 100 mA g⁻¹ and ca. 200 mA h g⁻¹ at a current density of 1000 mA g⁻¹ in 350 cycles. The superior cycling performance and high rate capability were attributed to the high theoretical specific capacity of Fe₃O₄, the catalytic activity of Fe₃C, the structural stability of TiO₂, and the buffer function of carbon fiber. Compared with the corresponding Fe₃O₄/Fe₃C/C and TiO₂/C composite fibers, the Fe₃O₄/Fe₃C/TiO₂/C product exhibited higher cycling and rate performances due to the synergetic effect among the Fe₃O₄, Fe₃C, TiO₂ and carbon components. [ABSTRACT FROM AUTHOR]