Synthesis and characterization of uniform hollow TiO₂ nanofibers using electrospun fibrous cellulosic templates for lithium-ion battery electrodes

Owing to its low structural strain and non-toxicity, TiO₂ has gained immense attention as a safe electrode material for lithium-ion batteries (LIBs). In this study, we fabricated nanoscale fibrous cellulosic templates via electrospinning. These templates were then used to fabricate one-dimensional hollow TiO₂ electrodes by the sol-gel method and subsequent calcination at various temperatures. The TiO₂ hollow nanofibers (HNFs) were composed of tiny (5 nm) anatase TiO₂ nanoparticles. The nanofibers maintained this particle size and the anatase phase at the calcination temperature up to 400 °C. The optimized TiO₂ HNFs, when used as the LIB anodes, exhibited a high reversible specific capacity of 152 mA h g⁻¹ at a current density of 185 mA g⁻¹ and 81% cyclic retention at the 100th cycle. These excellent electrochemical properties of the nanofibers can be attributed to their optimized phase and unique hollow nanostructure with large surface area, which provided them an efficient electrode/electrolyte contact area and faster ion/electron diffusion.