Electrospun Bi-doped TiO2/C nanofibers as active materials for high-capacity and long-life-stability sodium-ion anodes.

[Display omitted] • A novel Bi doped TiO 2 /C nanofibers (TiO 2 -Bi/CNFs) nanofibers are prepared. • The electrode exhibits the excellent stability of TiO 2 and the high capacity of Bi. Novel Bi-doped TiO 2 /C nanofibers (TiO 2 -Bi/CNFs) were fabricated using electrospinning combined with a consequent thermal treatment. When used as an active anode material for sodium-ion batteries (NIBs), interaction of Bi nanoparticles with TiO 2 incorporated into the carbon nanofibers stabilize the electrochemical performance of the material. Additionally, TiO 2 -Bi/CNF-based composite demonstrated high capacity and enhanced Na+ diffusion. As a result, NIB with TiO 2 -Bi/CNF-based anode displayed reversible capacity equal to 276 and 145.9 mAh g-1 after 200 and 3000 cycles at 100 and 1000 mA g−1 current densities, respectively. Even at 2000 mA g−1 current density, the battery with a TiO 2 -Bi/CNF-based anode delivered 84.5 mAh g-1 capacity retention after 10,000 cycles. Such excellent performance makes TiO 2 -Bi/CNFs a very promising active anode material for NIBs to advance large-scale energy storage applications. [ABSTRACT FROM AUTHOR]