Photoluminescence and thermoluminescence of Ce3+ ions doped in LiAl5O8 and NaAl11O17 aluminate systems

The aluminate phosphors LiAl5O8:Ce; NaAl11O17:Ce were synthesized by combustion synthesis. Photoluminescence (PL) and thermoluminescence (TL) characteristics of the phosphors have been reported in this paper. The Photoluminescence (PL) emission spectra of the LiAl5O8:Ce phosphors show strong Ce3+ emission at around 310 nm for the excitation at wavelength of 254 nm and in NaAl11O17:Ce emission is at 350 nm for the excitation at 254 nm wavelength of light due to the 5d→4f transition. The TL glow curves of the LiAl5O8:Ce and NaAl11O17:Ce materials show a single peak at 245 °C and 255 °C respectively, indicating single type of trapping sites due to γ-irradiated effect. The relative intensities of the peaks are found to increase with different (from 0.1 Gy to 50 Gy) γ-ray exposure. The maximum TL sensitivity for 50 Gy dose of the LiAl5O8:Ce phosphor is nearly 1.38 times whereas NaAl11O17:Ce phosphor 5.69 times higher than commercially available standard CaSO4:Dy phosphor. These phosphors may be useful for TLD materials.