Effect of synthesis methods, doping methods, metals and metal contents on the dosimetric properties of lithium tetraborate

Abstract

Thermoluminescent dosimeter (TLD) needs to have some features such as; a simple glow curve structure, a high gamma ray sensitivity, low fading of TL signal, linear dose-response relationship, simple annealing procedure for reuse, chemical stability and inertness to extreme climatic variations, insensitive to daylight, suitable effective atomic number (Zeff), close to that of soft tissue which is 7.42. The effective atomic number of lithium tetraborate is (7.42), which is almost the same as that of the biological tissue. Due to that reason, in this research, Lithium tetraborate: Li2B4O7, has been synthesized by different methods, such as, high temperature solid state synthesis and solution assisted synthesis methods. After preparing the host material, Cu and Mn were doped with different concentrations. TL glow curves of Mn and Cu doped LTB samples produced by using different synthesis and doping methods and Ag, P and Mg co-doped samples were investigated for comparison. All samples prepared displayed TL response and the best TL signal was obtained from the sample produced by solid state synthesis and doped by solution assisted method with 0.1% Cu and 0.004% Ag. High temperature solid-state synthesis of LTB and high temperature solid-state doping of Mn gave better glow curves with 1 wt% Mn content than other products with different synthesis and doping methods and than other percentages of Mn in LTB with two separable glow peak at 77 °C and 280 °C with high intensity. The addition of Ag as co-dopant shifted the main glow peak to 200 °C. P increased the intensity of glow peak at 280 °C. Mg increased the glow curve complexity. © 2012 RAD Conference Proceedings. All rights reserved.