| Summary: | In this study, the structural, optical and thermoluminescence (TL) properties of lithium sodium borate (LNB) glass doped with Er3+ or Nd3+ ions were investigated. The glass dosimeters were prepared by using melt-quenching technique. The X – ray Diffraction (XRD) spectra had confirmed the amorphous nature of the glass samples. The absorption spectra of Er3+ ion doped LNB (LNB:Er) and Nd3+ ion doped LNB (LNB:Nd) glasses revealed hypersensitive transitions at (4I15/2?2H11/2) and (4I9/2 ? 4G5/2 + 2G7/2), respectively. Emission spectra of LNB glasses doped Er3+ ions had shown three violet bands centered at 369 nm (4G11/2?4I15/2), 396 nm (2P3/2?4I13/2) and 423 nm (2H9/2?4I15/2) and a blue band at 477 nm (2P3/2?4I11/2). Meanwhile, LNB glasses doped with Nd3+ ions had exhibited three prominent peaks of photoluminescence spectra which are green, orange and red bands centered at 538 nm (4G7/2 ? 4I9/2), 603 nm [4G7/2 ? 4I11/2, 4G5/2 ? 4I9/2] and 675 nm [4G7/2 ? 4I13/2, 4G5/2 ? 4I11/2], respectively. The introduction of rare earth ions into the glass system had led to the formation of glow curve with prominent peaks at 180 and 220 °C for LNB:Er and LNB:Nd, respectively. The optimum TL intensity of the prepared glasses was determined at 0.3 mol % of Er2O3 and 0.5 mol % of Nd2O3. A good linearity of the TL response against dose was achieved between 0.5 to 4.0 Gy. The sensitivity of 0.3 mol % of Er2O3 glass dosimeter was two times higher than the sensitivity of 0.5 mol % of Nd2O3. The calculated values of the effective atomic number (Zeff) for both compositions were 7.55 which is close to that of the human soft tissue (Zeff = 7.42). These promising features had demonstrated the potential of the studied glasses to be used as radiation.
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