Abstract
Lithium-oxygen (Li-O-2) batteries have received much attention due to the superior theoretical energy density. However, commercialization is still hindered by several challenges including the high charge overpotential and poor cycling stability. Herein, small particle-stacked TiO2 microspheres are successfully synthesized through a facile hydrolysis and hydrothermal method. Such unique architectures provide 3D framework with more catalytically active sites and rich porosity for the storage of discharge products and oxygen diffusion. Li-O-2 batteries utilizing the TiO2 microspheres electrode show a much higher specific capacity and a lower overpotential than those with pure carbon nanotube (CNT) electrodes. Moreover, they exhibit an enhanced cycling stability and TiO2 microspheres show great potential as a promising catalyst for Li-O-2 batteries.