Microwave-assisted synthesis of CaMoO4 nano-powders by a citrate complex method and its photoluminescence property

Nano-sized CaMoO4 powders, which have scheelite type structure, were successfully synthesized at low temperatures by a modified citrate complex method using microwave irradiation. The citrate complex precursors were heat-treated at temperatures from 300 to 700 °C for 3 h. Crystallizations of the CaMoO4 nano-sized powders were detected at 400 °C, and entirely completed at a temperature of 500 °C. Almost nano-powders of CaMoO4 heat-treated between 400 and 600 °C showed primarily spherical and homogeneous morphology. The average crystalline sizes of CaMoO4 were 12-27 nm at temperatures of 400-700 °C, showing an ordinary tendency to increase with the temperatures. The CaMoO4 powders prepared at 600 °C showed the strongest photoluminescence intensity.