Spray pyrolysis-deposited TiO2 thin films as high-performance lithium ion battery anodes

Abstract

Focusing on additive-free electrodes, thin films are of typical interest as electrodes for lithium ion battery application. Herein, we report the fabrication of TiO2 thin films by spray pyrolysis deposition technique. X-ray diffraction and transmission electron microscopic analysis confirms the formation of anatase TiO2. Electrochemical evaluation of these sub-micron TiO2 thin films exhibits high-rate performance and long cycling stability. At 1C rate (1C = 335 mA/g), the electrode delivered discharge capacity of 247 mAh/g allowing about 0.74 lithium into the structure. The electrodes also delivered specific capacities of 122 and 72 mAh/g at 10 and 30C rates, respectively. Without conductive additives, this excellent performance can be attributed to the nanosize effect of TiO2 particles combined with the uniform porous architecture of the electrode. Upon cycling at high rates (10 and 30C), the electrode exhibited excellent cycling stability and retention, specifically only < 0.6% capacity loss per cycle over 2500 cycles.