Freestanding hybrid electrospun membranes consisting of TiO2 nanotube-core nanocarbon as high-performance and long-lifespan anodes for lithium-ion batteries

To develop an efficient anode for lithium ion batteries (LIBs), we prepare an ultralong oxygen-deficient titanium dioxide nanotubes (TNTs)-based hybrid electrospun carbon nanofibers (CNFs) membrane (TNT@CNFs). As an anode, this membrane possesses several advantages, including fast ion/electron trans-port path due to the TNTs' novel structure, protection from direct contact between TNTs and electrolyte owing to the carbon skeleton, improved electrical conductivity on account of the internal structural con-sistency of TNTs, and enhanced ion transport because of oxygen vacancies. As a result, the anode with a relatively low content of TNT (33TNT@CNFs) exhibits an ultra-high reversible specific capacity of 350 mAh/g after 200 cycles at a relatively low current density (0.2 A/g), while the anode with a high content of TNT (50TNT@CNFs) exhibits an ultra-high rate performance of 187 mAh/g at 10 A/g after 10,000 cycles, in-dicating its superior electrochemical kinetics at high-rate and long cyclic lifespan. This can find proof from the dynamic analysis that both the surface capacitance process and the diffusion-controlled insertion have a great contribution. The strategy employed in this work can facilitate access to a variety of one-dimensional (1D) nanostructured composites and can promote new research on electrodes for ultrafast rechargeable LIBs.& COPY; 2023 Elsevier B.V. All rights reserved.