Three-dimensional TiO2 nanotubes immobilized with Fe2O3 nanoparticles as an anode material for lithium-ion batteries

Abstract

Transition metal oxides utilized as electrode materials that applied in lithium-ion batteries (LIBs) have been attracting considerable attentions due to their good electro-activities and high theoretical specific capacities, while the serious drawbacks are the poor cycling stability and irreversible capacity degradation upon cycling of the electrodes. In this work, a bio-inspired nanotubular TiO2/Fe2O3 composite was fabricated by using a natural cellulose substance (laboratory filter paper) as the structural scaffold, which was obtained by growth of FeOOH nanocrystals on the surfaces of the TiO2 nanotubes that templated by the cellulose nanofibers and successive calcination treatment. The composite possess a relatively high specific surface area, and it is composed of porous Fe2O3 nanoparticles that uniformly immobilized on the titania nanotubes surfaces. As applied to be an anode material for LIBs, it delivered the initial discharge and charge capacities of 948 and 686 mAh g−1, respectively; and it exhibited a cycling capacity of 571 mAh g−1 after 150 cycles at a current rate of 100 mA g−1 as well as good rate performances. The enhanced electrochemical properties of the composite are due to the three-dimensional network structure of it, which effectively prevents the pulverization and aggregation of the immobilized Fe2O3 nanoparticles during the lithiation/delithiation processes. Moreover, the nanostructured porous Fe2O3 nanoparticles provide more active sites and facilitate the charge transfer during the charge/discharge processes. Due to the synergistic effect of the Fe2O3 nanoparticles and the TiO2 nanotubes, the nanocomposite showed good cycling stability as well as excellent rate capability. This work shows the prospective potentials of bio-inspired metal oxides as high-performance electrode materials for LIBs.