A series of Dy3+and Er3+co-doped NaY(WO4)2phosphors were synthesized by hydrothermal reactions. X-ray diffraction and scanning electron microscope were used to characterize their crystal structure and morphology. The upconversion luminescent properties and the fluorescence lifetime of 4F9/2→6H13/2transition of the Dy3+ion were also investigated. Moreover, the energy transfer from Dy3+to Er3+ions in NaY(WO4)2: Dy3+, Er3+was ana-lyzed in detail. The results indicated that all the samples had pure tetragonal crystal structure. Furthermore, the micrometer-sized needle spheres and excellent dispersion of the particles were obtained by adding polyethylene glycol (PEG-2000) as surfactant. Under near infrared light excitation at 780 nm, the NaY(WO4)2: Dy3+, Er3+samples exhib-ited blue emission at 480 nm (4F9/2→6H15/2transition of Dy3+), yellow emission at 576 nm (4F9/2→6H13/2transition of Dy3+) and green emission at 531 and 554 nm (2H11/2→4I15/2and 4S3/2→4I15/2transition of Er3+, respectively). The en-ergy transfer process from Dy3+to Er3+is a resonant transfer, in which electric dipole-dipole interaction plays a leading role. By adjusting the doping concentration of Er3+in NaY(WO4)2: 1.0mol% Dy3+, xmol% Er3+phosphors, conversion from quasi white light to blue light can be realized.%采用水热法合成出Dy3+, Er3+共掺杂NaY(WO4)2荧光粉.利用XRD和SEM对样品的晶体结构及形貌进行表征.研究了上转换发光性能和Dy3+的4F9/2→6H13/2跃迁的荧光衰减曲线, 并讨论了Dy3+→Er3+的能量传递过程.结果表明: 所有合成的样品均具有 NaY(WO4)2四方相结构; 加入聚乙二醇(PEG-2000)作为表面活性剂, 可得到分散性良好的微米针状球; 在780 nm近红外光激发下, 观察到了480 nm蓝光、576 nm黄光、531 nm及554 nm绿光发射峰, 其中蓝光和黄光分别来自 Dy3+的4F9/2→6H15/2与4F9/2→6H13/2跃迁, 绿光发射由 Er3+的2H11/2→4I15/2和4S3/2→4I15/2跃迁产生.通过研究荧光光谱和荧光衰减曲线, 证实了 Dy3+→Er3+的能量传递过程, 且该能量传递的机制为电偶极–电偶极相互作用.通过调节NaY(WO4)2: 1.0mol% Dy3+, xmol% Er3+荧光粉中Er3+的浓度, 可实现由准白光到蓝光的转变.
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