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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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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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Eu2O3 doped silicoborate glasses for scintillation material application: Luminescence ability and X-ray imaging
(2023-12-01)
Intachai, N.
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Kothan, S.
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Wantana, N.
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Kaewjaeng, S.
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Pakawanit, P.
The glass samples were prepared by melt quenching method and changing Eu<inf>2</inf>O<inf>3</inf> concentrations following component of xEu<inf>2</inf>O<inf>3</inf> - 40Na<inf>2</inf>O - 7.5Gd<inf>2</inf>O<inf>3</inf> - 5SiO<inf>2</inf> - (47.5-x)B<inf>2</inf>O<inf>3</inf> (x = 0, 1, 2, 3 mol %). Density and molar volume tend to increase with increasing Eu<inf>2</inf>O<inf>3</inf> concentrations, corresponding to the larger non-bridging oxygen. Fourier transform infrared spectra (FTIR) results point out that the majority BO<inf>3</inf> borate group. The absorption spectra were represented in the length of UV-Vis and NIR region. The phonon energy of 3Eu:7.5Gd was 1280.54 cm−1, related to the borate glass host. The photoluminescence and X-ray-induced luminescence spectra of 3Eu:7.5Gd glass showed similar highest intensity at 613 nm (5D<inf>0</inf>→7F<inf>2</inf>). The photoluminescence quantum yield (PLQY) of 3Eu:7.5Gd glass shows the highest value at 85.70 %. The scintillation efficiency of 3Eu:7.5Gd glass was 17.51 % of bismuth germanate (BGO) crystal. The decay time owing to Eu3+ emission is 2.054 ms for 2Eu:7.5Gd glass. The highest energy transfer efficiency was 2 mol % of Eu<inf>2</inf>O<inf>3</inf> concentrations (η<inf>ET</inf> = 70 %). The CIE chromaticity coordinates of the glasses are placed in the reddish-orange area (0.65, 0.35). The spatial resolution of X-ray imaging study was 10 lp/mm. These results suggest that 3 mol % of Eu<inf>2</inf>O<inf>3</inf> doped silicoborate glass is capable of being a scintillator applied in the X-ray imaging system.
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Fabrication luminescence and radiation shielding properties of Gd2O3–La2O3–ZnO–B2O3–Sm2O3 glasses
(2023-01-01)
Kaewjaeng, S.
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Kothan, S.
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Wantana, N.
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Kim, H. J.
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Rajaramakrishna, R.
The purpose of developing high transparency radiation shielding materials and luminescence materials with stoichiometric ratio of xGd<inf>2</inf>O<inf>3</inf>:10La<inf>2</inf>O<inf>3</inf>:10ZnO:(79-x) B<inf>2</inf>O<inf>3</inf>: 1Sm<inf>2</inf>O<inf>3</inf> where x = 0, 5, 10, 15, and 20 mol% using melt quenching technique. The physio-optical properties such as molar volume, density, concentration of rare-earth ions, polaron radius, inter-ionic radius, optical basicity, average distance between rare-earth ions, and optical packing density of the present glasses has been evaluated. The glass samples obtained show high density which is vital factor for radiation shielding. The absorption spectra show significant of bands Sm3+ ions. The FTIR results of Gd-La-Zn-B-Sm (Gd-1Sm) glass samples show signature borate BO<inf>3</inf> and BO<inf>4</inf> vibrational units in Gd-1Sm glass samples. The μ, μ<inf>m</inf>, HVL, TVL, and MFP were evaluated and showed that the values decrease with increasing X-ray energy whereas increase with an increase in Gd<inf>2</inf>O<inf>3</inf> content suggesting their potential use in X-ray diagnosis regions. The HVL value was compared with commercial windows, concrete, Serpentine and X-ray windows and found that the glasses doped with 10 mol%, 15mol%, and 20 mol% Gd<inf>2</inf>O<inf>3</inf> content showed better results than X-Ray windows at 10 kVp. The emission and excitation spectra of glass samples were studied and emission spectra show orange emission bands. The experimental lifetime analysis shows that the glass samples show decreasing trend from 1.161 to 1.128 ms with an increase in Gd3+ ions exhibiting single exponential nature.
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Radio and photo luminescence properties of Dy3+ ion doped bismuth barium gadolinium borate glass
(2023-01-01)
Ruamnikhom, R.
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Yasaka, P.
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Boonin, K.
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Limsuwan, P.
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Kaewkhao, J.
Investigations on physical, optical and photo – radio luminescence properties of dysprosium doped bismuth barium gadolinium borate glass (BiBaGdBDy) have been prepared for the melt at 1200 °C and rapidly cooling in the casting process. The glasses were doped by Dy<inf>2</inf>O<inf>3</inf> with six concentrations which varied from 0.00 to 1.50 mol%. The cut and polished glass samples were measured density and refractive index at room temperature. The absorption spectra show at the wavelength 802, 891, 1083, 1265 and 1679 nm that that are matched with the transition of Dy3+ from 6H<inf>15/2</inf> (ground state) to various excited state 6F<inf>5/2</inf>, 6F<inf>7/2</inf>, 6F<inf>9/2</inf>, 6F<inf>11/2</inf> and 6H<inf>11/2</inf> respectively. The 387 nm flash lamp was used to excite the sample lead to display the five emission bands at 481, 576, 661 and 753 nm which matched with the emission transitions 4F<inf>9/2</inf>→6H<inf>J</inf> (J = 15/2, 13/2, 11/2 and 9/2) respectively. The prominent blue light from 4F<inf>9/2</inf>→6H<inf>15/2</inf> and yellow light from 4F<inf>9/2</inf>→6H<inf>13/2</inf> emissions was combined and produces white light emission, which is confirmed by the CIE chromaticity diagram. The certain Lifetime of important laser-level is 4F<inf>3/2</inf>, which shows a decreasing trend with the increase of Dy<inf>2</inf>O<inf>3</inf> concentration. The Judd-Ofelt (J-O) intensity parameters found the trend Ω<inf>2</inf> > Ω<inf>4</inf> > Ω<inf>6</inf>. The branching ratios (β<inf>R</inf>) transition probabilities (A<inf>R</inf>) and stimulated emission cross-sections (σ<inf>e</inf>) were estimated for 4F<inf>9/2</inf>→6H<inf>13/2</inf> transition they are the radiative properties that were used to figure out the potential benefit of these glasses for laser action in the visible region along these lines suggests that the present Dy3+ doped bismuth barium gadolinium borate glasses are suitable for white light applications and scintillator material.
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A critical review and future prospects of Dy3+-doped glasses for white light emission applications
(2022-09-01)
Chandrappa, V.
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Basavapoornima, Ch
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Venkatramu, V.
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Depuru, Shobha Rani
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Kaewkhao, J.
Rare-earth (RE)-doped glassy systems gained much interest because of its wide variety of applications in numerous potential fields that include optical fibers, solid state lasers, optical amplifiers, optical thermometry sensors, waveguides, infrared detectors, spectral converters, display devices, and so on. Within RE ions, the trivalent dysprosium (Dy3+) ion is the most unique and characteristic ion to examine emission properties for white light and visible display emitting devices. Because, Dy3+ ion emits two intense emissions in the blue (~480 nm) and yellow (~575 nm) regions that are assigned to the 4F<inf>9/2</inf>→6H<inf>15/2</inf> and 4F<inf>9/2</inf>→6H<inf>13/2</inf> transition energies, respectively. Under the excitation of blue laser, Dy3+ ions exhibit attractive yellowish white fluorescence emission with higher quantum efficiency. In view of the importance of identifying efficient luminescent emitting materials for the development of optical devices, the present work is to investigate white light emission in new glass composition of B<inf>2</inf>O<inf>3</inf> +TeO<inf>2</inf> +SrCO<inf>3</inf> +ZnO+ZnF<inf>2</inf> +Dy<inf>2</inf>O<inf>3</inf> glass and in turn to compare and discuss these results with reported Dy3+:glasses. The tabulated reported data bank for 68 Dy3+:glasses at one place should prove valuable information for future work on rationalization of theoretical and practical point of view to enrich white light emission quantification, simulation and systemization.

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