Eu2+掺杂KCaCl3晶体的生长及发光性能

通过坩埚下降法生长出不同物质的量分数Eu²⁺掺杂的KCa_1-xEu_xCl₃(x=0.005、0.01、0.02、0.03、0.05)单晶,并对晶体进行了X射线粉末衍射、热重、透过率、光致发光光谱、衰减时间、X射线激发发射光谱等测定。通过相图及结构分析,判断出该晶体为一致熔融化合物,并得出其为正交结构,晶胞参数为a=0.75604 nm,b=1.04823 nm,c=0.72657 nm,空间群为Pnma(62)。在紫外光的激发下,晶体在434 nm左右有一个宽的发射峰,对应于Eu²⁺的4f⁶5d¹→4f⁷跃迁;光致衰减时间1.473μs,晶体在X射线激发下的发光强度随Eu²⁺离子浓度增加而增强。

Growth and Luminescence Properties of Eu2+ Doped KCaCl3 Crystal

Single crystals of KCa_1-xEu_xCl₃(x=0.005,0.01,0.02,0.03,0.05)doped with different Eu²⁺ion molar fractions have been grown successfully by Bridgman-Stockbarger technique.The crystals were characterized by powder X-ray diffraction,thermogravimetry,transmittance,photoluminescence spectrum,decay time and X-ray excitation emission spectrum.Through phase diagram and structure analysis,the crystal is regarded as a congruent compound and belongs to orthorhombic system.The unit cell parameters are determined as:a=0.75604 nm,b=1.04823 nm,c=0.72657 nm,space group:Pnma(62).Under the excitation of ultraviolet light,the crystal exhibited a broad emission around 434 nm,which can be attributed to the4f⁶5d¹→4f⁷transition of Eu²⁺.The result exhibited that the emission spectra with the maximum which position was shifted from 427 to 436 nm with the increase of Eu²⁺doped concentration.The photolumimnescence decay time was 1.473μs,moreover,the intensity of X-ray luminescence spectra continued to increase with the Eu²⁺ion concentration.