Intrinsic Defect Engineering in Eu(3+) Doped ZnWO(4) for Annealing Temperature Tunable Photoluminescence

Eu(3+) doped ZnWO(4) phosphors were synthesized via the co-precipitation technique followed by subsequent thermal annealing in the range of 400–1000 °C. The phase, morphology, elemental composition, chemical states, optical absorption, and photoluminescence (PL) of the phosphors were characterized by X-ray diffraction, scanning electron microscopy, dispersive X-ray spectroscopy, X-ray photoelectron spectrometry, diffuse UV–vis reflectance spectroscopy, PL spectrophotometry, and PL lifetime spectroscopy, respectively. It is found that the PL from Eu(3+) doped ZnWO(4) is tunable through the control of the annealing temperature. Density functional calculations and optical absorption confirm that thermal annealing created intrinsic defects in ZnWO(4) lattices play a pivotal role in the color tunable emissions of the Eu(3+) doped ZnWO(4) phosphors. These data have demonstrated that intrinsic defect engineering in ZnWO(4) lattice is an alternative and effective strategy for tuning the emission color of Eu(3+) doped ZnWO(4). This work shows how to harness the intrinsic defects in ZnWO(4) for the preparation of color tunable light-emitting phosphors.