摘要
The phosphor BaB8O13：Eu^3＋ were synthesized by solid-state reaction, and their luminescent properties were studied under 254 and 147 nm excitation. The excitation spectrum showed two broad bands in the range of 100-300 nm： one was the host lattice absorption with the maxima at 160 nm and the other was Ba-O absorption overlapped with the CT band of Eu^3＋, which indicated that the energy of the host lattice absorption could be efficiently transferred to the Eu^3＋. The overlapped bands were tended to separate when monitored by different wavelength, which indicated that at least two Ba^2＋ sites were available in BaB8O13. The emissions of Eu^3＋ （612 nm） and Eu^2＋ （405 nm） were both observed in the emission spectra of BaB8O13：Eu^3＋ under the excitation of either 254 or 147 nm. With the doping concentration of Eu^3＋ increasing, the 612 nm emission was enhanced while 405 nm emission was decreased under 254 nm excitation, which was due to the persistent energy transfer from Eu^2＋ to Eu^3＋. While under 147 nm excitation, the 612 nm emission was quenched and the 405 nm emission was enhanced. It was concluded that the preferential excitation of Eu^2＋ under 147 nm excitation was one of the reasons for this facts.
The phosphor BaB8O13：Eu^3＋ were synthesized by solid-state reaction, and their luminescent properties were studied under 254 and 147 nm excitation. The excitation spectrum showed two broad bands in the range of 100-300 nm： one was the host lattice absorption with the maxima at 160 nm and the other was Ba-O absorption overlapped with the CT band of Eu^3＋, which indicated that the energy of the host lattice absorption could be efficiently transferred to the Eu^3＋. The overlapped bands were tended to separate when monitored by different wavelength, which indicated that at least two Ba^2＋ sites were available in BaB8O13. The emissions of Eu^3＋ （612 nm） and Eu^2＋ （405 nm） were both observed in the emission spectra of BaB8O13：Eu^3＋ under the excitation of either 254 or 147 nm. With the doping concentration of Eu^3＋ increasing, the 612 nm emission was enhanced while 405 nm emission was decreased under 254 nm excitation, which was due to the persistent energy transfer from Eu^2＋ to Eu^3＋. While under 147 nm excitation, the 612 nm emission was quenched and the 405 nm emission was enhanced. It was concluded that the preferential excitation of Eu^2＋ under 147 nm excitation was one of the reasons for this facts.
基金
supported by the Specialized Research Fund for the Doctoral Program of Lanzhou University of Technology (SB01200801)
