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Nanophosphors of barium strontium sulfate complex (Ba 1-x Sr x SO 4 ) 99.8% :Eu 0.2% (0 ≤ x ≤ 1) were prepared through the chemical co-precipitation method at room temperature. Precipitated samples were characterized using X-ray diffraction (XRD), dynamic light scattering (DLS) and high resolution transmission electron microscope (HRTEM) techniques. The obtained XRD patterns from the prepared nanophosphate series (Ba 1-x Sr x SO 4 ) 99.8% :Eu 0.2% exhibit an orthorhombic structure with semispherical particle shape. The lattice parameters of (Ba 1-x Sr x SO 4 ) 99.8% :Eu 0.2% solid crystals change and the cell volume decreases with the increase of x value of strontium. The thermoluminescence (TL) glow curves induced by gamma rays of (Ba 1-x Sr x SO 4 ) 99.8% :Eu 0.2% series were recorded and compared. The substitution of Ba 2+ by Sr 2+ cations shift the trap centers in the host of (Ba 1-x Sr x SO 4 ) 99.8% :Eu 0.2% material to the higher temperature side. The TL glow curve (GC) of sample with x = 0.12, with grain size ranging between 13–31 nm, reveals that it has deep trap centers, and higher TL sensitivity. The different heating rates effect of the glow peaks of samples with x = 0, 0.12 and 1 showed that they follow the first-order kinetics. These samples have been studied and analyzed with the help of both T stop experimental method, and the computerized glow curve deconvolution (CGCD) program. T m – T stop experiment indicates that there are three trapping levels in both (BaSO 4 ) 99.8% :Eu 0.2% and (SrSO 4 ) 99.8% :Eu 0.2% sulfate samples at 452, 489, 543 K and 487, 513, 530 K respectively, while five peaks at 458, 486, 499, 544 and 556 K in the complex GC of (Ba 0.88 Sr 0.12 SO 4 ) 99.8% :Eu 0.2% . These values are used as input for CGCD. The figure of merit (FOM) during fitting procedures is determined. |
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