Microstructural and electrochemical study of La0.5Li0.5TiO3

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Processo FAPESP: 05/58446-8

The La0.50Li0.50TiO3 powder was synthesized by the polymeric precursor method. The thermal evolution of the precursor powder heated from 350 degrees C to 700 degrees C was followed by means of Raman spectroscopy. The crystallization process of the powder was analyzed by X-ray powder diffraction (XRD). Rietveld analysis identified a highly crystalline perovskite phase during crystallization. However, a secondary phase, LiTi2O4, was also detected. The morphology of the powder was observed by field emission gun scanning electron microscopy (FEG-SEM), which revealed a microstructure of spherical and homogeneous grains. As for the electrochemical measurements, the chronopotentiometry technique was employed for construction of the charge discharge curves, whereas the reduction/oxidation processes were evaluated by cyclic voltammetry. The results gave evidence of two different steps, which indicates the presence of two different kinetic processes. (C) 2011 Published by Elsevier B.V.