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采用高温固相法制备了KNaCa 2 (PO 4 ) 2 :Eu 2+ 蓝色荧光粉, 并研究了材料的发光特性. 在400 nm近紫外光激发下, 材料呈非对称的单峰发射, 主峰位于470 nm. 监测470 nm发射峰, 对应的激发光谱覆盖200~450 nm, 主峰位于400 nm, 说明材料能够很好的吸收紫外-近紫外光, 发射蓝色光. 利用van Uitert公式计算了Eu 2+ 取代KNaCa 2 (PO 4 ) 2 中Ca 2+ 时所占晶体学格位, 得出461和502 nm发射分别归属于八配位和六配位的Eu 2+ 发射. 研究了Eu 2+ 掺杂浓度对KNaCa 2 (PO 4 ) 2 :Eu 2+ 材料发射强度的影响, 结果显示Eu 2+ 的最佳掺杂浓度为1mol%, 利用Dexter理论得出其浓度猝灭机理为电偶极-电偶极相互作用.

A method for the determination of Eu in Long-aferglow of the SrAl2O4:Eu2+, Dy3+ phospher samples by laser microemission spectral analysis was developed. And the accuracy of this method was studied. Analyses of Eu in Long-aferglow of the SrA1204: Eu2+, Dy3+ phospher samples, using the Eu (11) line at 412.973 nm, show that RSD of relative intensity of spectral lines is 4.3%, RSD of quantitative analysis is 7.4%, the average of quantitative analysis is 2.13%. Compared with the content before samples synthesized, it can be concluded that the content of Eu in the SrAl2O4:Eu2+, Dy3+ phospher samples synthesized by high temperature solid phase reaction has an obvious increase.

In this paper, the quality improvement of Laser Microprobe Emission Spectral Analysis (LMESA) lines in argon atmosphere at reduced pressure was experimentally investigated. The experimental setup consists of a YGJ-II laser micro-spectral analyzer and a photo-electro detection system. The temporal behavior and the intensity distribution of Cu I 324.7 nm and Cu I 327.4 nm lines of the copper alloy standard samples were studied. The results show that LMESA spectrum strongly depends on the environment gas, its pressure and the auxiliary excitation parameters. When the diameter at the end of graphite auxiliary electrodes is 1.5 mm, the distance between the electrodes is 4 mm, the center of the electrodes is 3 mm above the sample surface, the voltage of the auxiliary excitation is 1,300 V and the argon pressure is 33.2 Kpa, the emission time of Cu I 324.7 nm and Cu I 327.4 nm is about 500 microseconds longer than that in the air. The emission intensity of Cu I 324.7 nm and Cu I 327.4 nm is about 4 times higher than that in the air at the same pressure and is about 2 times higher than that in the air at normal pressure. The full width at half maximum of the spectral lines is obviously narrowed.

A series of SrIn2O4:Eu3+ phosphors are synthesized by a high temperature solid-state method, and their luminescent properties are investigated. They can be excited by 395-nm radiation, and produce red emission (619 nm); however, they have a low absorption of near-ultraviolet light with the wavelength of 400 nm?405 nm. When co-doped with A+ (A = Li, Na, K), the emission intensity of SrIn2O4:Eu3+ is significantly enhanced, but its emission and excitation spectral profile is unchanged. With co-doping Sm3+, not only is the emission intensity of SrIn2O4:Eu3+ enhanced, but also the absorption is broadened and strengthened in the range of 400 nm?405 nm. The effect of Sm3+-doped content on the emission intensity of SrIn2O4:Eu3+, Sm3+ is investigated, and the optimal Sm3+ content is 0.02 mol.