Single Step Solid-State Synthesis of Lanthanum Molybdate

Abstract

Abstract In this study, LaxMoyOz powders were synthesized by a cost-effective solid-state synthesis method. Four different heating cycles were designed to investigate the effects of synthesis temperature and holding time on lanthanum molybdate (LMO) formation, phase assemblies, particle size and morphology. X-Ray Diffraction (XRD) and scanning electron microscopy (SEM) studies were performed to observe crystal structure and particle morphology of synthesized powders. The results showed that nearly ninety percent β - La2Mo2O9 (43,3 nm crystal size) phase was obtained at 1000 °C for 6 h holding time. Longer holding times at 1000 °C favor more oxygen-rich compounds which cause recrystallization of various new crystalline phases. The grain size of the synthesized powder was increased from 0,2 µm to 1,5 µm with increasing holding time. In summary, it is possible to manufacture LMO powders rich in β - La2Mo2O9 by one - step solid - state synthesis method. The phase assembles and particle size of LMO powders could also be tailored by optimization of heat treatment cycle.