Synthesis and Characteristic of CaMoO_4:Eu~(3+) Red Phosphor for W-LED by Co-precipitation

Using NH4HCO3-NH3·H2O as a mixed precipitator,CaMoO4:Eu3+ red phosphor was successfully synthesized by chemical co-precipitation method.The processes of thermal decomposition and phase formation for CaMoO4:Eu3+ precursor were analyzed by TG-DTA and XRD.Compared with solid-state method,both surface morphology and luminescence properties of CaMoO4:Eu3+ red phosphor using precipitators NH4HCO3,NH3·H2O and NH4HCO3-NH3·H2O are evaluated by means of SEM and PL respectively.After calcination at 700℃,the precursor is completely converted to a single scheelite structure of CaMoO4:Eu3+.Photoluminescence intensity of the phosphor reaches the maximum value at 900 ℃.The phosphor prepared by using mixed precipitator is uniform spherical particle,and has no aggregation with average size of 0.9μm.Compared with solid-state method,the Eu-O CTS of the red phosphor slightly shifts toward long wavelength.The strong electron absorbability of 7F0→5L6(394nm) and 7F0→5D2(465nm) effectively improves the performance of red phosphor.In addition,the photoluminescent intensity from the mixed precipitation is increased to 2 times of that of the red phosphors prepared by solid-state method.