Experimental and theoretical Raman study on the structure and microstructure of Li0.30La0.57TiO3 electrolyte prepared by the sol-gel method in acetic medium
By Mariano Romero and Ricardo Faccio and Santiago V
Published in Ceramics International
2016
Abstract
In this report, we prepare \LLTO\ ceramics by the sol-gel method in acetic medium. Raman spectroscopy showed the formation of lanthanum and titanium acetates precursors, which after calcination, lead to formation of the \LLTO\ nanoparticles. Raman spectra were scanned directly over the \LLTO\ pellets and the disappearance of impurities was observed during the microstructure evolution with increasing sintering temperature. X-ray diffraction characterization, including full pattern profile fitting refinements, showed no drastic changes in the unit cell parameters of the \LLTO\ perovskite, but a large increase in the crystallite size domain was observed with increasing sintering temperature. Additionally, an interesting structural phase transition for the Li0.30La0.57TiO3 perovskite structure was observed, from tetragonal P4/mmm to distorted-cubic Pm-3m spacegroup, for the highest sintering temperature (Ts=1300