Facile synthesized TiO2 with excellent electrochemical performances for lithium-oxygen batteries

Abstract

Benefited from the super-high theoretical energy storage density, the rechargeable lithium–oxygen batteries (LOBs) are perceived as a shiniest energy conversion and storage devices with the highest potential. To gain the stable and long-life cycle performance and high-efficiency energy storage device, developing of non-toxic, environmental protection and price moderate cathode catalyst is a vital component to the application of the LOBs. Here, TiO2 nanomaterials, as low cost, environmentally friendly and effective cathode catalyst had been synthesized with a facile hydrothermal method and followed calcination processes. The structure, surface morphology and the growth mechanism of the as synthesized TiO2 nanotubes, TiO2 nanofibers were studied in detail. When they were applied as cathode materials for LOBs, TiO2 nanotubes exhibits better electrochemical performance and good cycling stability for over 132 cycles accompanied by a fixed capacity of 600 mAh g−1 at a current density of 200 mA g−1, which is better than the TiO2 nanofibers. The good performances could be originated from the high specific surface area and the large amounts of oxygen vacancy in the TiO2 nanotubes samples.