Thermoluminescence characteristics of Mn doped SrAl₂O₄ phosphor

Abstract The structure and thermoluminescence (TL) characteristics of beta-irradiated Mn (1%)-doped SrAl 2 O 4 have been investigated. The sample was synthesized by the solution combustion method. Rietveld refined x-ray diffraction pattern of SrAl 2 O 4 :Mn reveals that the sample is predominantly in monoclinic phase with space group P 2 1 . The average crystallite size is 27 nm, estimated from the size-strain plot (SSP) method. Electron paramagnetic resonance showed that valence state of Mn ions in SrAl 2 O 4 is 2+. TL glow curve of beta irradiated (50 Gy) SrAl 2 O 4 :Mn shows two prominent peaks reproducible at 120 ± 1 °C and 350 ± 2 °C. The peaks overlapped in the TL glow curve is assessed using T m -T stop method. Here, kinetic parameters of the prominent peak (120 °C) were estimated from the whole glow peak, variable heating rate (VHR) and glow curve deconvolution methods. The activation energy of the peak at 120 °C is 0.89 eV calculated using the VHR method. The activation energy of thermal quenching of the peak at 120 °C is found to be 1.12 ± 0.05 eV. This report educates the TL properties of SrAl 2 O 4 :Mn and its kinetic analysis.