[The VUV luminescence properties and the Ce3+-->Tb3+ energy transfer in the (Sr, Ba)Al12O19].

The (Sr, Ba)Al12O19 : RE3+ (RE = Ce, Tb) compounds have been synthesized by the solid state reaction technology. The single-phase magnetoplumbite-type crystal structure has been identified by the X-ray diffraction analysis. The 302 nm peak and approximately 340 nm not-clear shoulder are correspondence to the 5d-->2 F5/2 and 5d-->2 F7/2 transitions in the emission spectrum, respectively. The 158 nm peak and 260 nm peak are separately contributed to the host absorption and 4f-5d transition of Ce3+ in the excitation spectrum. The characteristic emission of 5 D3-->7 Fj (j = 2, 3, 4, 5) and 5 D4-->7 Fj (j = 4, 5, 6) transitions in the range of 400-600 nm are assigned in the emission spectrum of (Sr, Ba)Al12O19 : Tb0.05(3+). The approximately 160 nm peaks arises from the overlap of the Tb3+ -O2- charge transfer band and the host absorption The 193 nm and 233 nm peaks are attributed by the spin-allowed 4f-5d transition and the spin-forbidden transition, respectively. The overlap between the emission of Ce3+ and the f-f transition absorption of Tb3+ exists in the (Sr, Ba)Al12O19 : Tb3+, Ce3+ compounds. The luminescence intensity of Tb3+ increases with the increase of the Ce3+ ion concentration When the Ce3+ ion concentration reaches about 0.03 mole, the luminescence intensity of Tb3+ ion is nearly two times comparing with the non-codoping Ce3+ ion compounds. When the emission wavelength is 543 nm, the excitation spectra exhibit the 4f-5d absorption of Ce3+ besides the host absorption and 4f-5d transitions of Tb3+ in the (Sr, Ba)Al12O19 : Tb3+, Ce3+ compounds. According to the excitation spectrum, the part of the emission of Tb3+ comes from the absorption of Ce3+ ion Therefore, it is illustrated that the Ce3+-->Tb3+ energy transfer has been existed in the (Sr, Ba)Al12O19 : RE3+ (RE = Ce, Tb) compounds.