Synthesis, luminescent and dosimetric properties of Li2B4O7:Cu,Ag,Tm

• Published in: Journal of materials science. Materials in electronics Vol. 31; no. 15; pp. 12191 - 12205
• Main Authors: González, P. R., Ávila, O., Mendoza-Anaya, D., Escobar-Alarcón, L., González-Romero, A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2020; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper; Crystallography; Dosimeters; Dosimetry; Energy value; Gamma rays; Heating rate; Lithium borates; Lithium fluoride; Materials Science; Morphology; Optical and Electronic Materials; Photoluminescence; Radiation dosage; Raman spectroscopy; Silver; Thulium
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-03765-1

This work reports the preparation of a new thermoluminescent (TL) material obtained by doping the host salt of lithium borate with copper, silver and thulium ions (Li 2 B 4 O 7 :Cu, Ag, Tm). With the obtained material, sintered dosimeters in form of discs were made and exposed to gamma radiation from a 60 Co source. It was found that these dosimeters show a sensitivity of approximately 40% of that shown by the commercial dosimeter TLD-100 (LiF:Mg,Ti). The thermally stimulated luminescence of the prepared material showed a linear response with dose for gamma radiation in the dose range from 0.001 to 50 Gy. Its luminescent signal remains constant during 24 h after irradiation, exhibiting a better behaviour than the commercial dosimeter TLD-800 (Li 2 B 4 O 7 :Mn) which decreases up to 60% of its original signal in the same period. The lower detection limit was determined to be equal to 0.1 mGy and TL measurements showed repeatability within 2.5%. The kinetic parameters were determined using several methods. The variable heating rate method showed the lowest energy value E of the main peak (peak 1). Initial rise and peak shape methods showed intermediate values whereas the deconvolution method showed the highest energy value E , using heating rates of 1, 2, 6 and 10 K/s. Results obtained from the morphology, crystallography, Raman spectroscopy and photoluminescence are also reported. These results suggest that this new thermoluminescent detector could be a promising material to use in clinical dosimetry applications.