[VUV excited luminescence of LnZr(BO3)2 : Eu3+ (Ln = Ba, Sr)]

Powder samples of Ba(1-x) Sr(x)Zr(BO3)2 : Eu3+ (0 < or = x < or = 1) were prepared by the conventional solid state reaction method. The excitation spectrum shows a strong absorption in the VUV region with the broad absorption band edge at 130-170 nm due to the host and the f --> d transition of Eu3+, and another absorption band of charge-transfer state (CTS) of Eu3+ in the region of 230 nm. The absorption of the charge-transfer band of Eu3+ can be increased by incorporating Al3+ ion into Zr4+ ion lattice. The luminescence of Ba(1-x) Sr(x)Zr(BO3)2 : Eu3+ is also increased by incorporating Al3+ into the lattices. In Ba(1-x) Sr(x)Zr (BO3)2 : Eu3+, the intensity of the absorption band (130-170 nm) decreases, and the band shifts about 30 nm toward lower energy with x increasing. The emission spectra revealed an intense and sharp (616 nm) red color emission from Eu3+ (5 Do --> F2) transition under 147 nm VUV excitation.