Abstract: Gd₂O₂S:Dy³⁺  phosphors were synthesized by a homogeneous precipitation method from Gd₂O₃, Dy₂O₃, H₂SO₄ and Urea starting materials. The characterizations of Gd₂O₂S:Dy³⁺  phosphors were investigated by means of XRD, FE-SEM and PL spectra. XRD analysis shows that the precursor can be transformed into pure Gd₂O₂S powder by calcining at 900 ℃ for 1 h in hydrogen. FE-SEM observation shows that the Gd₂O₂S powder particles are quasi-spherical in shape, with a mean particle size of about 300~500 nm. Photoluminescence (PL) spectroscopy reveals that the main and second emission peaks are located at 579 nm and 488 nm under 270 nm UV light excitation, which corresponds to the ⁴ F_9/2→⁶H_13/2 and the ⁴F_9/2→⁶H_15/2 transitions of Dy³⁺ ions, and both transitions of Dy³⁺ ions have a single exponential decay behavior. The quenching concentration of Dy³⁺ ions is 1 %. The CIE coordinate and the color temperature of (Gd_0.99,Dy_0.01)₂ O₂S phosphor are (0.308, 0.379, 0.313）and 6 464 K respectively.

Key words: Gadolinium oxysulfide , Phosphor , Homogeneous precipitation , Photoluminescence

摘要：    采用Gd₂O₃, Dy₂O₃, H₂SO₄ 和尿素为实验原料，通过均相沉淀法合成了Gd₂O₂S:Dy³⁺ 荧光粉。利用Ｘ射线衍射（ＸＲＤ）、场发射扫描电子显微镜（ＦＥ－ＳＥＭ）和光致发光（ＰＬ）光谱对合成的粉体进行了表征。ＸＲＤ分析表明：前驱体在氢气气氛下９００℃煅烧２ｈ能转化成单相的Ｇｄ_２Ｏ_２Ｓ粉体。ＦＥ－ＳＥＭ 观察显示：Gd₂O₂S粉体形貌为近球形，平均粒度大小为３００～５００ｎｍ。ＰＬ光谱分析表明：在２７０ｎｍ紫外光激发下，Gd₂O₂S:Dy³⁺ 荧光粉的主次发射峰分别位于５７９和４８８ｎｍ，分别归属于Dy³⁺的^{4 F_9/2→6H_13/2}和 ^{4F_9/2→6H_15/2}  跃迁，这两个跃迁均具有ｅ单指数衰减行为。Dy³⁺ 的猝灭摩尔分数是１％，（Ｇｄ０．９９，Ｄｙ０．０１）２Ｏ２Ｓ荧光粉的色坐标和色温分别为（０．３０８，０．３７９，０．３１３）和６　４６４Ｋ。

关键词: Ｇｄ_２Ｏ_２Ｓ , 　荧光粉 , 　均相沉淀法 , 　光致发光