Electrospinning preparation of oxygen-deficient nano TiO2-x/carbon fibre membrane as a self-standing high performance anode for Li-ion batteries

摘要

Improving the specific capacity and electronic conductivity of TiO₂ can boost its practical application as a promising anode material for lithium ion batteries. In this work, a three-dimensional networking oxygen-deficient nano TiO_2-x/carbon fibre membrane was achieved by combining the electrospinning process with a hot-press sintering method and directly used as a self-standing anode. With the synergistic effects of three-dimensional conductive networks, surface oxygen deficiency, high specific surface area and high porosity, binder-free and self-standing structure, etc., the nano TiO_2-x/carbon fibre membrane electrode displays a high electrochemical reaction kinetics and a high specific capacity. The reversible capacity could be jointly generated from porous carbon, full-lithiation of TiO₂ and interfacial lithium storage. At a current density of 100?mA?g?1, the reversible discharge capacity can reach 464?mA?h?g?1. Even at 500?mA?g?1, the discharge capacity still remains at 312?mA?h?g?1. Compared with pure carbon fibre and TiO₂ powder, the TiO_2-x/C fibre membrane electrode also exhibits an excellent cycle performance with a discharge capacity of 209?mA?h?g?1 after 700 cycles at the current density of?300?mA?g?1, and the coulombic efficiency always remains at approximately 100%.