Ultrasound assisted synthesis of nano-sized lithium cobalt oxide

Nano-sized HT-LiCoO 2 powders were prepared by sonochemical synthesis in an aqueous solution of lithium hydroxide containing cobalt hydroxide at ∼80 °C without any further heat treatment at high temperature. The effects of the LiOH concentration, oxidation conditions, ultrasound irradiation time and temperature on the formation of the nano-sized HT-LiCoO 2 phase were investigated. The formation of the HT-LiCoO 2 phase was confirmed by X-ray diffraction and Raman spectroscopy. The TEM images showed the presence of HT-LiCoO 2 aggregates with a mean particle diameter of ∼20 nm. The reaction mechanism of the ultrasound assisted synthesis of nano-sized LiCoO 2 was proposed on the basis of the XRD, X-ray absorption spectroscopy analysis and TEM observation of the reaction products taken during the course of the synthesis.