采用水热法合成了不同Tb³⁺浓度掺杂的单分散球形BaWO₄绿色荧光粉。通过粉末X射线衍射(XRD)和扫描电子显微镜(SEM),能量色散光谱仪(EDS)来表征荧光粉的晶体结构、颗粒大小、形貌及成分;激发光谱和发射光谱以及荧光衰减曲线来表征荧光粉的荧光性能。XRD分析确认不同Tb³⁺浓度掺杂的BaWO₄具有白钨矿结构;SEM图像显示不同 Tb³⁺浓度掺杂BaWO₄为单分散的球形荧光粉以及颗粒大小为2-4 μm。研究Tb³⁺离子掺杂浓度对发光强度的影响,结果表明,荧光粉中Tb³⁺离子的最佳掺杂原子数分数为12%。发射光谱表明在254 nm的UV光激发下12% BaWO₄:罷b荧光粉样品与商用绿色荧光粉LaPO4:罜e,Tb发光强度相当。由于Tb掺杂的BaWO₄绿色荧光粉具有优良的发光性能和容易制备的特点,有望成为新一代的绿色荧光粉。

Monodispersed spheres for Tb³⁺-doped BaWO₄ phosphors are synthesized by a hydrothermal method. X-ray diffraction (XRD),and field-emission scanning electron microscopy (SEM),energy dispersive spectrometer (EDS) are used to characterize the resulting samples of crystal phase structure,particle size and morphology and composition. Photoluminescence excitation and emission spectra and decay curve are used to characterize the fluorescence properties of phosphors. XRD analysis confirms the formation of BaWO₄ with scheelite structure. SEM study shows that the obtained BaWO₄:Tb phosphors of different Tb³⁺ concentrations appear to be dispersed spheres and their particle sizes range from 2 to 4 μm. Analysis of the photoluminescence spectra with different Tb³⁺ concentration reveals that the optimum dopant concentration is about 12% of Tb³⁺ions in BaWO₄:罷b phosphors. Photoluminescence spectra indicate the phosphors emit strong green light centered at 545 nm under 254 nm UV light excitation in comparison with the commercial green fluorescent lamp phosphor (LaPO4:罜e,Tb). The results shows that the intensity of BaWO₄:罷b phosphors is comparable to that of LaPO4:罜e,Tb.The excellent luminescence properties make it a new promising green phosphor for fluorescent lamps application.