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.