Synthesis of Lu2Ti2O7 powders by molten salt method

Lu2Ti2O7 ceramic powder with pyrochlore structure was synthesized in molten salt with NaCl as salt flux, under different salt-to-oxide mole ratios of 1:1, 3:1 and 5:1 in the temperatures range of 800-1100 degrees C. It was found that the synthesizing temperature and salt-to-oxide ratios had significant effects on the morphology of Lu2Ti2O7 powder. The microstructure observation revealed that the crystal morphology of Lu2Ti2O7 powder changed from spheroid to octahedron, and then became irregular after further increasing temperature. When the temperature was increased beyond 1000 degrees C, a duplex microstructure could be formed. Further investigations revealed that the ratio of salt to oxide affected the crystalline of Lu2Ti2O7 from the molten salt flux although the grain size of the synthesized powder was not found to increase greatly by an increment of the molten salt content. (C) 2011 Elsevier B.V. All rights reserved.