为了研究浓度效应对Sr1-xAl2O4∶xEu晶体粉末光谱和色度特性的影响,采用溶液-燃烧法制备了不同掺杂浓度的Sr1-xAl2O4∶xEu晶体粉末样品,通过X射线衍射(XRD)和X射线激发发光(XEL)手段,对粉末样品的晶体结构和光谱特性进行表征,研究浓度效应对样品光谱和CIE色度特性的影响。XRD检测表明,溶液-燃烧法制备的Sr1-xAl2O4∶xEu晶体粉末具有α单斜晶相结构。在X射线激发下,晶体粉末呈现Eu2+绿色荧光和Eu3+红色荧光发射。随着Eu掺杂浓度的增加,晶体粉末的527nm绿色荧光发射强度逐渐增强,在摩尔浓度为x=0.016时达到最大,而后开始淬灭衰减;而616nm的红色荧光强度逐渐增强,在x=0.300时仍未出现淬灭效应。采用CIE 1931标准色度理论,计算了不同掺杂浓度样品的(x,y)色度坐标,结果显示晶体粉末的色调从绿色区域经黄绿和黄橙色区域逐步过渡到橙红色区域。
To investigate the chromaticity properties and fluorescence spectroscopy of SrAl2O4∶Eu excited by X-ray,the Sr1-xAl2O4∶xEu crystal powders with various coping concentration were synthesized via a urea assisted solution-combustion method.The crystal powders were characterized by X-ray powder diffraction (XRD) and X-ray excited luminescence spectroscopy.The XRD showed that the synthesized samples exhibited a monoclinic α-SrAl2O4 phase.Under the X-ray excitation,the crystal powders exhibited Eu2+ green fluorescence and Eu3+ red fluorescence emission.The intensity of green fluorescence emission around 527nm increased with increasing europium concentration up to a maximum of x=0.016,then decreased due to concentration quenching effect,while the intensity of red fluorescence around 616 nm increased with increasing europium concentration even x=0.300.The (x,y) chromaticity coordinates of samples with different doping concentration were calculated.The CIE 1931 chromatogram shown that the fluorescence of the sample gradually transited from the blue-green region to the red region through the green region.
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