Surfactant-assistant solvothermal synthesis of CaWO4:Eu3+ phosphors and luminescence

• The successful co-doping of Eu3+ ions in CaWO4.
• The morphology control of CaWO4:Eu3+ by adding different surfactants.
• The highest emission intensity of microspheres with smooth surface.

CaWO4:Eu3+ phosphors with different morphologies were synthesized by the surfactant-assistant solvothermal process. The structure and luminescent properties were characterized by XRD, SEM, TEM, IR, XPS, and spectrophotometer. The XRD and IR results show that the samples have the scheelite phase. The XPS result shows that Eu3+ ions have doped into CaWO4 hosts successfully. PEG-400, En, and EDTA play the key roles in the formation of microspheres with smooth surface, microspheres with rough surface, and microoctahedrons, respectively. All samples show emission bands originating from the 5D0 → 7Fj (j = 1, 2, 3, 4) transitions of Eu3+ ions. The morphology has obvious influence on the emission intensity. The microspheres with smooth surface have the highest emission intensity, and the microoctahedrons have the lowest emission intensity.