Preparation and photoluminescence properties of YAl3(BO3)4:Tb3+, Bi3+ phosphor under VUV/UV excitation

The huntite structured YAl3(BO3)4:Tb3+, Bi3+ phosphor was prepared by a solid state reaction method. The emission lines due to the 5D4–7FJ (J = 0, 1, 2, 3, 4, 5, 6) and 5D3–7FJ (J = 4, 5, 6) transitions of Tb3+ ions were observed, and the main emission wavelength was about 545 nm due to 5D4–7F5 transition. Without Bi3+ ions, the main emission intensity of the Y1−xTbxAl3(BO3)4 sample with x = 0.3 was the highest. However, the PL intensity of 5D3–7F5 emission was decreased due to the cross-relaxation from 5D3 to 5D4 with increase of the Tb3+ concentration. Although the host absorption band below 165 nm was decreased by addition of Bi3+ ions, the 1S0 → 1P1 and 1S0 → 3P1 transitions of Bi3+ ions enhanced the luminescence of Tb3+ ions under excitation ranging from 165 nm to 205 nm and from 250 nm to 290 nm, respectively.