Ce3+激活NaSr4(BO3)3荧光粉的格位占据和发光性质研究

采用高温固相法制备了一系列可被紫外光有效激发的Na_1+xSr_4-2x(BO₃)₃∶xCe³⁺荧光粉,并通过X射线衍射、扫描电镜、荧光光谱等测试方法对样品的物相结构、形貌和发光特性进行了表征及分析。X 射线衍射结果显示,Ce³⁺成功掺入到基质NaSr₄(BO₃)₃中;利用高斯峰拟合、多光谱对比等手段,分析并验证了发光中心Ce³⁺占据了NaSr₄(BO₃)₃中Sr²⁺(1)和Sr²⁺(2)两个格位;研究了不同浓度Ce³⁺的掺杂对发光位置和发光强度的影响,随着Ce³⁺掺杂浓度的提高,发射光谱出现红移,发光强度出现增强→减弱→再增强的趋势;将荧光粉的发射光谱与植物光合色素吸收光谱进行对比,发现它不仅可以吸收300~350 nm的紫外光,发射光谱还很好地覆盖了植物光合色素所需的蓝光区吸收波段,证明其在农业生产的转光剂方面有潜在应用价值。

Site Occupation and Luminescence Properties of Ce3+ Activated NaSr4(BO3)3 Phosphors

A series of Na_1+xSr_4-2x(BO₃)₃∶xCe³⁺ phosphors which can be excited by ultraviolet light were prepared by high temperature solid phase method. The phase structure, morphology and luminescence characteristics of the samples were characterized and analyzed by X-ray diffraction, scanning electron microscopy and fluorescence spectrum. X-ray diffraction results show that Ce³⁺ is successfully doped into NaSr₄(BO₃)₃. It is found that luminescence center of Ce³⁺ occupied Sr²⁺(1) and Sr²⁺(2) in NaSr₄(BO₃)₃ by means of Gaussian peak fitting and contrastive analysis of multiple spectra. The effects of Ce³⁺ doping concentration on the luminescence location and luminescence intensity were studied. With the increase of Ce³⁺ doping concentration, the emission spectra show a red shift and the luminescence intensity shows a trend of enhancing→weakening→re-enhancing. By comparing the emission spectra of phosphors with the absorption spectra of plant photosynthetic pigments, it is found that the phosphors can not only absorb 300~350 nm UV light, but also well cover the absorption band of blue light region required by plant photosynthetic pigments. This results show that the phosphor has potential value in agricultural production as a light conversion agent.