Preparation of lanthanum cerate powders via a simple molten salt route

Lanthanum cerate (La2Ce2O7) powders were synthesized via a simple molten salt route using cerium oxide (CeO2) and lanthanum oxide (La2O3) as raw materials, and KCl-LiCl, Na2CO3-K2CO3 and NaCl-KCl-NaF to form the reaction media. The effects of different processing parameters such as reaction temperature, salt type and salt/reactant ratio on the La2Ce2O7 formation were investigated. Among the three combined salts, NaCl-KCl-NaF showed the best accelerating effect on the La2Ce2O7 formation. Phase pure La2Ce2O7 particles with sizes of 2-5 mu m were obtained after 3 h firing at 1100 degrees C in NaCl-KCl-NaF using the salt/reactant ratio of 3.0:1.0. Use of an appropriately higher amount of molten salt was beneficial to the formation of finer La2Ce2O7 particles. The "dissolution-precipitation" mechanism is believed to have played a key role in the synthesis process. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.