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Development of BaO-containing radiation-shielding glass using natural dolomite as a raw-material component
(2027-01-01)
Cheewasukhanont, W.
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Kothan, S.
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Tungjai, M.
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Intachai, N.
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Ruangtaweep, Y.
This study investigates the incorporation of dolomite (CaMg(CO<inf>3</inf>)<inf>2</inf>) as a natural substitute for synthetic CaO in the fabrication of radiation shielding glass (RSG). Dolomite samples from Kanchanaburi, Thailand, were characterized using X-ray fluorescence (XRF) to determine their chemical composition, revealing CaO (76.59-79.84 wt%) and MgO (19.13-21.54 wt%) as the primary components. These dolomites were used to synthesize borosilicate-based host glasses, where density remained stable (∼2.5 g/cm3), ensuring structural integrity. Optical transmittance measurements showed an average 80% transparency in the visible range. To enhance radiation attenuation, BaO was incorporated into the glass matrix at varying concentrations (5-35 mol%). Increasing BaO content increased the density of the glass samples, which contributed to improved radiation attenuation performance. The radiation-shielding properties, predicted using WinXCom over a wide photon energy range and experimentally evaluated at 0.662 MeV, improved with increasing BaO content. The HVL, Pb-equivalent thickness, and EABF results further supported the enhanced attenuation performance of the developed glasses, indicating that higher BaO content reduced the contribution of scattered photons to absorbed energy buildup in the intermediate-energy region. In addition, preliminary glass-forming tests of the B4 composition demonstrated the feasibility of preparing a larger glass sheet under similar melting and annealing conditions, although further optimization is still required. These findings suggest that natural dolomite can serve as a useful raw-material component for developing BaO-containing radiation-shielding glass with balanced optical transparency, density, and attenuation performance.
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Radioluminescence properties of silicate-phosphate glass system based on “Huta Ginjang” quartz sand co-doped with Gd3+/Tb3+ ions for scintillation applications
(2026-11-01)
Rajagukguk, J.
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Hutahaean, Juniar
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Situmorang, Howard
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Sarumaha, C. S.
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Simanullang, E.
A series of mixed silicate-phosphate glasses co-doped with Gd3+/Tb3+ ions at varying Tb concentrations were successfully synthesized using the melt-quenching technique. Their physical, optical and luminescence properties were analyzed, with an emphasis on the role of Tb3+ concentration. The photoluminescence (PL) spectra exhibit characteristic emission bands corresponding to Gd3+ and Tb3+ ions. A gradual decrease in the Gd3+ emission intensity at 311 nm is observed, accompanied by the suppression of Tb3+ emissions originating from the 5D<inf>3</inf> level. In contrast, a significant enhancement of the green emission associated with the Tb3+5D<inf>4</inf> → 7F<inf>j</inf> transitions is clearly evident. Under X-ray excitation, the radioluminescence (RL) spectra of the glasses displayed multiple sharp emission peaks corresponding to Tb3+ transitions, in contrast to the broad 478 nm emission band of the BGO crystal. Integral RL intensity ratios were demonstrated; all glasses exhibit significant radioluminescence intensity under X-Ray excitation compared to BGO, with QSPCaBaGd<inf>5</inf>Tb<inf>2.0</inf> showing the highest performance reaches up to 52.09% in the 350-800 nm range. These results, together with X-ray imaging capability, demonstrate that the developed glasses are promising candidates for cost-effective scintillation applications.
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Enhanced luminescence and scintillation performance of Ce-doped silico- and germanophosphate glasses for ultra-high resolution synchrotron X-ray imaging applications
(2026-06-15)
Sarumaha, C. S.
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Kaewnuam, E.
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Kantuptim, P.
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Nishikawa, A.
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Kato, T.
Ce-doped phosphate, silicophosphate and germanophosphate glasses with the composition 25Li<inf>2</inf>O+ 10ZnO+ 5Gd<inf>2</inf>O<inf>3</inf>+xR+ (59.5-x)P<inf>2</inf>O<inf>5</inf>+ 0.5CeF<inf>3</inf> (x = 0, 10 mol%; R = SiO<inf>2</inf> and GeO<inf>2</inf>) were prepared by the conventional melt quenching. This study highlights the novel role of network modification (SiO<inf>2</inf> and GeO<inf>2</inf> substitution) in enhancing the scintillation and imaging performance of Ce3 + -activated phosphate-based glasses; this topic remains inadequately researched. Structural analyses (FTIR, Raman) demonstrated that network modifications influence density and optical properties, with germanophosphate showing the highest density (3.07 g/cm3) and high transparency of around 80%. Notably, silicophosphate glass exhibits ∼12 times higher photoluminescence intensity than phosphate glass, with an experimental quantum yield of 24.8%. Under X-ray excitation, strong emission bands were observed from Gd3+ (310 nm) and Ce3+ (∼337 nm). The integrated ratio of radioluminescence (RL) emission was calculated and followed the order silicophosphate > phosphate > germanophosphate, indicating optimal luminescence enhancement via Si incorporation. The superior scintillation response of the silicophosphate glass is further validated by pulse height measurements under 241Am α-ray excitation. Silicophosphate glass was selected for its superior scintillation response, further confirmed by 2D/3D imaging and line-pair (MTF and contrast) analyses, demonstrating its suitability for ultra-high-resolution synchrotron X-ray imaging applications.
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Optical and emission Spectroscopy and radiation shielding properties of Sm3+-Doped P2O5 + BaO + La2O3 glasses
(2026-01-01)
Kesavulu, C. R.
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Masthanaiah, E.
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Basavapoornima, Ch
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Depuru, Shobha Rani
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Pecharapa, Wisanu
Within lanthanide series, Sm3+(4f5) ion is relatively very complex electronic structure and similar to Dy3+(4f9) ion but both ions exhibit visible and infrared emissions. As such, characteristics (structural, thermal, optical, luminescence, etc.) of Sm3+ ion doped crystals, glass-ceramics, phosphors and glasses have been widely investigated for development of visible photonic devices, scintillators and magnetic components. In this paper, studies carried out so far on physical, structural, luminescence and optical characteristics of Sm3+-embedded glasses have been collected, tabulated and re-analysed in a systematic procedure besides our own work on P<inf>2</inf>O<inf>5</inf> + BaO + La<inf>2</inf>O<inf>3</inf> + Sm<inf>2</inf>O<inf>3</inf> (PBaLaSm) glasses. All the quantified properties have also been reviewed besides the labeling of glass compositions in a meaningful way. The properties that are reviewed include, optical energy gap, Judd-Ofelt (JO), radiative, etc. The obtained JO parameters ( × 10−20 cm2) for the present glasses are Ω<inf>2</inf> = 5.57, Ω<inf>4</inf> = 5.22 and Ω<inf>6</inf> = 3.37. In the case of Sm3+ ion, it has been noticed that the JO analysis found to be not only sensitive to the co-ordination geometry of the surrounded glass composition but also on the number of absorption levels that are used for the JO analysis. Theoretical radiation shielding results for the studied glass found to be better than the RS-253-G18, RS-360, lead and ordinary concrete at 30 and 40 KeV. The decay rates for 4G<inf>5/2</inf> level of Sm3+ ions in the PBaLaSm glasses have been measured and are found to exhibit single exponential nature at lower concentration and turns into non-exponential at higher concentrations (≥1.0 mol % Sm<inf>2</inf>O<inf>3</inf>-doped glasses). The experimental lifetimes for 4G<inf>5/2</inf> level of Sm3+ ions are found to decrease from 2413, 2383, 2129, 2039, 1299 and 259 μs when concentration increases from 0.01, 0.05, 0.1,0.5, 1.0 and 2.0 mol % due to cross-relaxation energy transfer. The non-exponential decay rates are well-fitted to Inokuti-Hirayama model for S = 6, indicates that the energy transfer is of dipole-dipole type. However, the overall observations outlined in this study for 48 Sm3+:glasses may be quite useful for those who are interested in this thrust area to plan and carryout systematic study to get constructive conclusion besides predictive nature.
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Enhancement of gamma and X-ray shielding behaviors in ZnO-B2O3 glasses via La2O3 addition: Experimental and theoretical investigations
(2025-12-01)
Yabsantia, S.
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Wantana, N.
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Chusin, T.
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Kaewjaeng, S.
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Ornketphon, O.
Radiation shielding materials are crucial for reducing radiation exposure. Traditional materials such as lead, and concrete pose challenges related to toxicity and lack of transparency. This study aimed to assess the effects of lanthanum oxide (La<inf>2</inf>O<inf>3</inf>) addition on physical, optical, and radiation shielding properties of ZnO–B<inf>2</inf>O<inf>3</inf> glass systems. Glass samples of (80-x)B<inf>2</inf>O<inf>3</inf>–20ZnO-xLa<inf>2</inf>O<inf>3</inf> (x = 5–20 mol%) were prepared using the melt-quenching technique and characterized for density, molar volume, refractive index, transmittance and X-ray diffraction (XRD). Gamma-ray shielding performance was evaluated using the Compton scattering method with a Cs-137 source and NaI(Tl) detector, alongside theoretical data from WinXCOM. X-ray shielding capabilities were determined through experimental transmission measurements and Monte Carlo simulations (PHITS) across effective energies ranging from 30.40 to 44.21 keV. Increasing La<inf>2</inf>O<inf>3</inf> content (5–20 mol%) resulted in higher density (2.89–3.63 g/cm3), slightly increased molar volume (29.37–33.98 cm3/mol), and higher refractive index (1.58–1.65). All La<inf>2</inf>O<inf>3</inf>-added glasses exhibited ∼75 % transmittance in the visible region. XRD analysis indicated amorphous characteristics for all samples. For gamma rays, both experimental and theoretical results agreed well, showing improved shielding with higher La<inf>2</inf>O<inf>3</inf> levels. For lowest gamma-ray energy, the 20 mol% sample had the highest mass attenuation coefficient (μ<inf>m</inf>) of 0.21 cm2/g, lowest half value layer (HVL) of 0.89 cm, and shortest mean free path (MFP) of 1.29 cm. For X-rays, PHITS simulations and experiments also aligned, with μ<inf>m</inf> up to 4.21 cm2/g (at 30.40 keV), HVL of 0.05 cm, and MFP of 0.07 cm. These findings suggest that La<inf>2</inf>O<inf>3</inf> addition enhances both gamma and X-ray shielding effectiveness. In conclusion, the study highlights the potential of La<inf>2</inf>O<inf>3</inf>-added ZnO–B<inf>2</inf>O<inf>3</inf> glass as an alternative shielding material, with future research aimed at further improving its shielding performance.
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Ca co-doped CsI(Tl) crystal scintillator for γ- and X-ray detecting applications
(2025-01-01)
Tariwong, Y.
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Kim, H. J.
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Quang, Nguyen Duy
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Khan, Arshad
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Daniel, D. Joseph
The vertical Bridgman method is used for the growth of single-doped CsI(Tl) and CsI(Tl:Ca) crystals, which has been evaluated for feasible applications in X-ray imaging and radiation detection. The powder XRD technique study reveals a single-crystalline phase of the grown crystal. The emission spectra show a broad emission band with a maximum of 540 nm under X-ray excitation, along with the characteristic emissions that arose from the Tl+ intra-center transition. The scintillation qualities of the grown crystal were studied via the pulse height spectra, scintillation light yield, energy resolution, and scintillation decay time. Pulse shape discrimination (PSD) was investigated under γ-rays and α-particles excitation sources. Moreover, the X-ray imaging application was investigated by an X-ray synchrotron at the Synchrotron Light Research Institute to study the performance of the grown crystal. These preliminary investigations suggest that the grown CsI(Tl:Ca) crystal can be one of the promising crystals for γ- and X-ray detecting applications.
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A novel material for radiation detection application of zinc bismuth lithium borotellurite glass doped with Dy2O3
(2024-12-01)
Sommat, V.
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Ornketphon, O.
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Kaewjaeng, S.
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Kothan, S.
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Limsuwan, P.
Radiation detection glass with the following chemical composition B<inf>2</inf>O<inf>3</inf>–TeO<inf>2</inf>–Li<inf>2</inf>O<inf>3</inf>–Bi<inf>2</inf>O<inf>3</inf>–ZnO doped with Dy<inf>2</inf>O<inf>3</inf> where x = 0.00, 0.10, 0.50, 1.00, 1.50 and 2.00 mol%, was developed for the characterization of physical properties such as density, molar volume (V<inf>m</inf>), and refractive index, optical absorption, luminescence, CIE's diagram, and radiation detection properties. The density and refractive index of glass samples increase with the increase of Dy<inf>2</inf>O<inf>3</inf> composition. The optical property of glass shows eight strongest peaks from 6H<inf>15/2</inf> centering at 263 nm (4I<inf>13/2</inf> + 4F<inf>7/2</inf>), 298 nm (4G<inf>11/2</inf>), 357 nm (4I<inf>15/2</inf>), 803 nm (6F<inf>5/2</inf>), 897 nm (6F<inf>7/2</inf>), 1090 nm (6H<inf>7/2</inf> + 6F<inf>9/2</inf>), 1272 nm (6F<inf>11/2</inf> + 6H<inf>9/2</inf>) and 1671 nm (6H<inf>11/2</inf>), respectively. The emission peaks are r (4F<inf>9/2</inf>), 481 nm (6H<inf>15/2</inf>), 575 nm (6H<inf>13/2</inf>), 664 nm (6H<inf>11/2</inf>), and 751 nm (6H<inf>9/2</inf>) under excited at 453 nm (4F<inf>9/2</inf>), respectively. The excitation peaks under emission at 575 nm from 6H<inf>15/2</inf> centering at 350 nm (6P<inf>7/2</inf>), 365 nm (4P<inf>3/2</inf>), 388 nm (4K<inf>17/2</inf>), 425 nm (4G<inf>11/2</inf>), 453 nm (4I<inf>15/2</inf>), and 471 nm (4F<inf>9/2</inf>) respectively. The study of luminescence characteristics, which includes emission, excitation, and CIE diagrams, reveals white emission bands that coincide with the CIE diagram. Furthermore, measuring the parameters of the thermoluminescence dosimeter (TLD) recorded with a heating rate of 5 °C/s in the temperature up to a maximum of 400 °C yields good results in low dose radiation detection. Based on all the results, it was determined that this glass can be a candidate for radiation detection materials in the future.
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Structural, optical, luminescence spectroscopy and radiation shielding properties of Eu3+:borophosphotellurite glasses
(2024-10-01)
Masthanaiah, E.
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Basavapoornima, Ch
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Lokanadham, R.
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Pecharapa, Wisanu
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Kaewkhao, J.
Recently much effort is being paid to study the rare earth ions in multi component glass formers as they exhibit high enhancement in the efficiency of luminescence properties. In this direction, the present study focuses on the preparation and analysis of novel glass batches with composition of (in mol %) BPTCZEu: 40B<inf>2</inf>O<inf>3</inf>+20P<inf>2</inf>O<inf>5</inf>+15TeO<inf>2</inf>+ 10CaO+(15−x)ZnO + xEu<inf>2</inf>O<inf>3</inf>, x = 0.1, 0.5, 1.0, 1.5, 2.0 and 2.5. The important spectroscopic techniques such as optical absorption, luminescence, excitation and decay curves are taken to analyse the BPTCZEu glasses. Luminescence spectrum of BPTCZEu comprise of emission from excited (5D<inf>0</inf>) to the lower multiplets (7F<inf>J</inf> (J = 0−4)), among these, 5D<inf>0</inf> → 7F<inf>2</inf> (red luminescence) at 612 nm found to be very intense. Judd−Ofelt characteristics, Ω<inf>2</inf>, Ω<inf>4</inf> and Ω<inf>6</inf>, were derived from different constraints. To know the site symmetry around Eu3+, the fluorescence intensity ratio of 5D<inf>0</inf> → 7F<inf>2</inf> vs. 5D<inf>0</inf> → 7F<inf>1</inf> were analysed. Exciting 7F<inf>0</inf> → 5L<inf>6</inf> and monitoring 5D<inf>0</inf> → 7F<inf>2</inf>, the lifetime of 5D<inf>0</inf> level is determined to be 2 ms which is independent of Eu3+ content. The colour coordinates for all the Eu3+ concentrations are estimated to fall in the reddish−orange region. Theoretical radiation shielding results showed that substituting Eu<inf>2</inf>O<inf>3</inf> for ZnO in the glasses lowers photon number that can pass via the material, enhancing the glass system's trend to shield high energy radiation. These stimulated results are compared with experimental measurements of mass attenuation coefficient with respect to energy up to 662 KeV using Cs−137 source. All these findings obtained from title glasses are compared and discussed with respect to reported Eu3+:glasses and no systematic variation has been noticed either with single, bi− or multi−component glass formers and therefore needs further systematic work to relate Eu−radiation−ligand interaction.
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Novel Tb3+ doped borophosphate glass scintillator for X-ray imaging
(2024-10-01)
Khrongchaiyaphum, F.
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Wantana, N.
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Kaewnuam, E.
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Pakawanit, P.
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Phoovasawat, C.
In this study, we introduce an efficient green-emitting material made from Tb3+ doped borophosphate scintillating glass for X-ray imaging. An influence of Tb<inf>2</inf>O<inf>3</inf> concentration on the physical, optical, luminescent, and scintillation properties of glasses were investigated. The glass density and refractive index increase, while the molar volume and Tb3+ inter-ionic distance decreases with Tb<inf>2</inf>O<inf>3</inf> addition. These glasses absorb the photons in range of UV, Vis, and NIR. The excitations by UV and X-ray on glasses causes the strong green emission centered around 545 nm by the 5D<inf>4</inf> → 7F<inf>5</inf> transition of Tb3+. The energy transfer from Gd3+ to Tb3+ was occurred in this emission. The glass doped with 4 mol% of Tb<inf>2</inf>O<inf>3</inf> demonstrates the highest emission intensity at 545 nm due to the concentration quenching. The decay time of glasses are in few milliseconds. The integral X-ray scintillation efficiency of 4 mol% doped glass is 52% compared to that of BGO crystal. Additionally, this glass was proceeded in the X-ray imaging and yielded the image with satisfied resolution, characteristics and MTF values, compared to that obtained from YAG:Ce crystal. The developed glass has a potential for X-ray imaging applications, especially in the medical imaging, flaw detection, and security inspection.
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Spectroscopic investigation and local structure of Eu3+ ions in lead phosphate glasses for optical device applications
(2024-04-01)
Basavapoornima, Ch
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Masthanaiah, E.
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Vijaya, N.
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Depuru, Shobha Rani
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Kaewkhao, J.
Phosphate-based glasses are promising materials which are being employed for broad range of applications whereas Eu3+ is an efficient activator due to its predominant 5D<inf>0</inf> →7F<inf>2</inf> emission (red region). In this direction, an attempt has been made to investigate the effect of Eu3+ ions doped lead phosphate glasses (PPbKANEu: P<inf>2</inf>O<inf>5</inf>+PbO+K<inf>2</inf>O+Al<inf>2</inf>O<inf>3</inf>+Na<inf>2</inf>O+Eu<inf>2</inf>O<inf>3</inf>) to explore possible photonic device applications. Optical absorption, excitation, photoluminescence and decay rates are used to characterize the PPbKANEu glasses. The photoluminescence spectrum of Eu3+:PPbKAN glasses exhibit emission channels from the first excited (5D<inf>0</inf>) to the ground (7F<inf>J</inf> (J =0–4)) multiplets. To determine the local site symmetry of surrounding Eu3+ ions, the relative fluorescence intensity ratio of 5D<inf>0</inf>→7F<inf>1</inf> versus 5D<inf>0</inf>→7F<inf>2</inf> emission channels has been analyzed. The emission spectrum of PPbKANEu glasses exhibits a comprehensive lifting of degeneracy of 5D<inf>0</inf>→7F<inf>2</inf> and 5D<inf>0</inf>→7F<inf>1</inf> emission channels. By considering C<inf>2v</inf> symmetry for Eu3+ ions, the second (B<inf>0</inf>2= −406 and B<inf>2</inf>2=−158) and fourth (B<inf>0</inf>4=980, B<inf>2</inf>4=297 and B<inf>4</inf>4=926 cm–1) rank crystal–field (CF) characteristics were estimated along with CF strength factor (S= 402 cm–1). The lifetime of 5D<inf>0</inf> state is estimated to be 2.09, 2.23, 2.21 and 2.21 ms for 0.1, 0.5, 1.0 and 2.0 mol% of Eu3+ ions, respectively. The analysis of the decay times reveals that the lifetime of 5D<inf>0</inf> state is less affected by the concentration of the Eu3+ ion. The results are compared and discussed with reported values and confirm the potentiality of the PPbKANEu glasses for optical device applications in visible regions.

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