Luminescence characteristics of Li₂CO₃-K₂CO₃-H₃BO₃ glasses co-doped with TiO₂/MgO

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• 作者：Yasser Saleh Mustafa Alajerami ; Suhairul Hashim ; Sib Krishna Ghoshal ; Ahmad Termizi Ramli ; Muneer Aziz Saleh ; Zuhairi Ibrahim ; Taiman Kadni ; David Andrew Bradley
• 关键词：Thermoluminescence dosimetry ; Photoluminescence ; Lithium potassium borate glass ; Doping
• 刊名：Applied Radiation and Isotopes
• 出版年：December, 2013
• 年：2013
• 卷：82
• 期：Complete
• 页码：12-19
• 全文大小：1762 K

文摘

Understanding the influence of co-dopants in the luminescence enhancement of carbonate glasses is the key issue in dosimetry. A series of borate glasses modified by lithium and potassium carbonate were synthesized by the melt-quenching method. The glass mixture activated with various concentrations of TiO₂ and MgO was subjected to various doses of gamma-rays (⁶⁰Co). The amorphous nature of the samples was confirmed by x-ray diffraction (XRD) spectra. The simple glowing curve of the glass doped with TiO₂ features a peak at 230 掳C, whose intensity is maximal at 0.5 mol% of the dopant. The intensity of the glowing curve increases with the concentration of MgO added as a co-dopant up to 0.25 mol%, where it is two times higher than for the material without MgO thermoluminescence properties, including dose response, reproducibility, and fading were studied. The effective atomic number of the material was also determined. Kinetic parameters, such as kinetics order, activation energy, and frequency factor are estimated. The photoluminescence spectra of the titanium-doped glass consist of a prominent peaks at 480 nm when laser excitation at 650 nm is used. A three-fold photoluminescence enhancement and a blue shift of the peak were observed when 0.1% MgO was introduced. In addition, various physical parameters, such as ion concentration, polaron radius and internuclear distances were calculated. The mechanism for the thermoluminescence and photoluminescence enhancements are discussed.