Wydział Chemii

Małgorzata Puchalska

Paulina Bolek

Katarzyna Kot

Eugeniusz Zych

2020

Optical Materials

107

109999/1-109999/7

10.1016/j.optmat.2020.109999

Naukowa

Angielski

Artykuł

Bismuth-doped SrAl₄O₇ powders were synthesized via modified Pechini process and their photoluminescence, radioluminescence and thermoluminescence properties were studied and discussed. Obtained results showed that in studied materials bismuth is present in two valence states, Bi³⁺ and Bi²⁺. Upon UV excitation SrAl₄O₇:Bi powders yield broad multicomponent luminescence in the 350–670 nm range, associated with the ³P_0,1 → ¹S₀ transition of Bi³⁺ ions, and the most intense component located in green (λ_max = 515 nm) part of spectrum. It was found that the emission spectral distribution is excitation wavelength-dependent. By changing the excitation wavelength in the 270–340 nm range the emission colour can be modulated from blue, through bluish-cyan to green. The studied phosphors also showed broad-band ²P_3/2 → ²P_1/2 Bi²⁺ emission in deep red region centered at around 710 nm. This luminescence was found predominant in radioluminescence and thermoluminescence spectra, which is deemed unique for bismuth-doped materials. The Bi²⁺ 630–830 nm emission might be attractive for bioimaging as it appears in the I^st biological window and may be utilized for deep red scintillation.

SrAl4O7, Bismuth, Luminescence, Radioluminescence, Thermoluminescence, Decay kinetics

http://dx.doi.org/10.1016/j.optmat.2020.109999

http://www.elsevier.com