Microwave-assisted synthesis of barium molybdate by a citrate complex method and oriented aggregation

BaMoO₄ powders, which have scheelite type structure, were successfully synthesized at low temperatures by a modified citrate complex method assisted by microwave irradiation. The citrate complex precursors were heat-treated at temperatures from 300 to 500 °C for 3 h. Crystallization of the BaMoO₄ powders were detected at 350 °C, and completed at a temperature of 400 °C. TEM image of the BaMoO₄ product obtained above 400 °C revealed spindle-rods-like or flake-like morphology. The anisotropic growth habit of BaMoO₄ leads to the oriented aggregation, which is attributed to the high chemical potentials of the intrinsic structure of BaMoO₄. The BaMoO₄ powder prepared at 500 °C showed the strongest photoluminescent intensity.