An Overview on Preparation and TL Characterization of Lithium Borates for Dosimetric Use

Abstract

Boron that appears in borate form in nature is an essential additive to a variety of industrial products. Recently, certain boron compounds have attracted attention in high technology utilization areas owing to their special crystal and optical characteristics. Thermoluminescent (TL) dosimetry that is used to record amount of radiation exposure is one of such areas. Two borates searched for candidacy in TL dosimetry are lithium tetraborate and lithium triborate. These materials are synthesized and metal doped by numerous researchers to be tested for thermoluminescence response. Lithium tetraborate has aroused interest of scientists since 1960s by the courtesy of the thermoluminescence (TL) property. However, lithium triborate is rather new in this area. This study compromises a broad overview including synthesis methods employed for the production of these two materials. Furthermore, the TL properties that have significant effect on the TL dosimetry potential of a compound are noted along with the detailed information on TL measurement procedure specifications.Keywords: Thermoluminescence, dosimetry, lithium borates, synthesis, doping, characterization. BORATESThere are several natural and synthetic borates used in different branches of industry. Natural borates are generally cleaned from their impurities in processing plants and are further treated to more qualified end products (like boric acid, anhydrous boric acid, anhydrous borax, borax pentahydrate,borax decahydrate and sodium perborate) in recrystallizer units. Besides, the variability of borate crystal chemistry [1] allows researchers synthesize numerous borate structures usable in high technology areas. Thermoluminescent (TL) dosimetry used to measure radiation exposure is an important high technology utilization area for these synthetic borates. General Uses of Borates in High TechnologyIt is certain that the interesting crystal structure of borates play an important role for its utilization in high technology. Although the utilization variety of borates is strongly related to its structural variety, in this communication we will concentrate on results of these characteristics rather than chemical background. Indeed, there is extensive number of studies devoted to the crystal structures of borates [1][2][3] which may be refered for detailed information.Owing to the varied crystallinity borates possess large electronic band gaps, attractive nonlinear optical (NLO) properties, chemical and environmental stability, and mechanical strength [3]. Hence, they found wide use in *Address correspondence to this author at the Middle East Technical University, Mining Engineering, Ankara, Turkey; Tel: +903122102664; Fax: +903122105822; E-mails: epekpak@metu.edu.tr, ayseny@metu.edu.tr nonlinear optical technologies as well as in thermoluminescence dosimetry.Borates have high UV transmittance at wavelengths down to 155 nm [4]. Therefore, they are appropriate for the use in plasma displays and in laser technology. Furthermore they are strong phosphors which ...

Thermoluminescence Properties of Aluminium Oxide doped Strontium, Lithium and Germanium prepared by Combustion Synthesis method

“…This may be due beyond 3 mol% concentration, quenching is bound to occur hence the optimum concentration for Ge only suite for this concentration. Highest TL intensity at 3 mol% Ge is attributed to the recombination of the excited electrons from the valences band with defects produced via irradiation [29]. As a conclusion, it is found that the optimum concentration value of Ge dopants is at 3 mol% with very low standard error.…”

“…Recently, interest of Ge as dopants for dosimetric purpose has increased. Based on previous study, Ge doped optical fibre as a thermoluminescence dosimeter in radiotherapy is a promising material because it gives good response an fullfill the criteria of thermoluminescence properties [24]. Due to limitation study of CS technique especially for Al2O3 doped with Li, Sr and Ge dopants, for this present investigation, we report preliminary studies on the possibility of growing Al2O3 with different dopants and characterizing them for thermoluminescnet studies.…”

Novos Materiais Dosimétricos para Aplicações em Física Médica

“…Os TLD-600/TLD-700 são comumente utilizados para dosimetria de nêutrons albedo. Os TLD-600 são sensíveis a nêutrons térmicos e à radiação gama, enquanto que os TLD-700 servem para discriminar a contribuição da radiação gama na resposta dos TLD-600 24 11,26,[38][39][40][41][42][43] . Cristais dopados com Cu e Ag apresentaram alta intensidade TL e baixo limite de detecção para doses de radiação 44 .…”

Thermoluminescence characterization of Ag‐doped Li2B4O7 single crystal materials

“…Each product gains distinctive TL characteristics on addition of a variety of activators during the production process. One of the fundamental techniques of crystal growth used to obtain LTB as a single crystal is the Czochralski method named after Jan Czochralski …”

“…One of the fundamental techniques of crystal growth used to obtain LTB as a single crystal is the Czochralski method named after Jan Czochralski. [1] Borate-based compounds can be produced relatively easy because of their good heat stability and low melting point. [2] Various forms of Li 2 B 4 O 7 , namely Cu-, Mn-and Eu-doped single crystals, polycrystalline and glassy samples have been prepared for dosimetric applications.…”