Статті в журналах з теми "Borate Glass Matrices"

Theoretical calculations of mass attenuation coefficients, partial interactions, atomic cross-section, and effective atomic numbers of PbO-based silicate, borate, and phosphate glass systems have been investigated at 662 keV. PbO-based silicate glass has been found with the highest total mass attenuation coefficient and then phosphate and borate glasses, respectively. Compton scattering has been the dominate interaction contributed to the different total attenuation coefficients in each of the glass matrices. The silicate and phosphate glass systems are more appropriate choices as lead-based radiation shielding glass than the borate glass system. Moreover, comparison of results has shown that the glasses possess better shielding properties than standard shielding concretes, suggesting a smaller size requirement in addition to transparency in the visible region.

Glass samples with 3 B 2 O 3· Bi 2 O 3 and B 2 O 3· Bi 2 O 3 matrices containing up to 30 mol% Y 2 O 3 were prepared by melt fast quenching method. The effect of yttrium addition on the local order in glasses was investigated by infrared spectroscopic analysis. The results indicate that the local structure is more ordered in the glass system with higher bismuth content and the progressive addition of yttrium increases the local disorder in both bismuth-borate glass matrices.

The results presented in this communication concern visible and near-IR emission of Pr3+ ions in selected inorganic glasses, i.e., borate-based glass with Ga2O3 and BaO, lead-phosphate glass with Ga2O3, gallo-germanate glass modified by BaO/BaF2, and multicomponent fluoride glass based on InF3. Glasses present several emission bands at blue, reddish orange, and near-infrared spectral ranges, which correspond to 4f–4f electronic transitions of Pr3+. The profiles of emission bands and their relative intensity ratios depend strongly on glass-host. Visible emission of Pr3+ ions is tuned from red/orange for borate-based glass to nearly white light for multicomponent fluoride glass based on InF3. The positions and spectral linewidths for near-infrared luminescence bands at the optical telecommunication window corresponding to the 1G4 → 3H5, 1D2 → 1G4, and 3H4 → 3F3,3F4 transitions of Pr3+ are dependent on glass-host matrices and excitation wavelengths. Low-phonon fluoride glasses based on InF3 and gallo-germanate glasses with BaO/BaF2 are excellent candidates for broadband near-infrared optical amplifiers. Spectroscopic properties of Pr3+-doped glasses are compared and discussed in relation to potential optical applications.

Some bismuth-borate oxide glass' samples were prepared by the fast quenching method, where B2O3 was replaced with equal concentrations of ZnO and CaO. X-ray diffraction (XRD) was used to examine the internal structure and Fourier transform infrared (FTIR) to identify building units and bonds throughout the studied structural matrices. XRD showed that all samples have short range order structural nature, while FTIR demonstrated some of Zn2+ acted as glass network formers and all Bi3+ acted as glass. UV-visible measurements and calculations showed a decreasing in the energy band gap from 3.83 eV to 1.73 eV with decreasing B2O3 content. Also with decreasing B2O3 content, both real refractive index and metallization factor decreased from 3.1 to 1.9 and from 0.56 to 0.71, respectively. For the studied glass' samples, density and molar volume showed inverted behaviors, where the density decreased while the molar volume increases with decreasing B2O3.

Two completely different glass-host matrices containing lead, i.e. borate and germanate glasses doped with erbium were studied. Replacement of glass-former B2O3 by GeO2 in amorphous host was evidenced by optical methods. The luminescence decay from the 4I13/2 upper laser state of Er3+ ions is relatively short, whereas up-converted emission signal is reduced definitely in borate glass containing lead due to its high B-O stretching vibrations. The results indicate that germanate glasses containing lead are promising for near-infrared luminescence and up-conversion applications. Full Text: PDF ReferencesR. Balda, A. Oleaga, J. Fernandez, J.M. Fdez-Navarro, "Spectroscopy and frequency upconversion of Er3+ ions in lead niobium germanate glasses", Opt. Mater. 24, 83 (2003). CrossRef H. Yamauchi, Y. Ohishi, "Spectroscopic properties of Er3+-doped PbO?Ga2O3?GeO2 glass for optical amplifiers", Opt. Mater. 27, 679 (2005). CrossRef W.A. Pisarski, Ł. Grobelny, J. Pisarska, R. Lisiecki, W. Ryba-Romanowski, "Spectroscopic properties of Yb3+ and Er3+ ions in heavy metal glasses", J. Alloys Compd. 509, 8088 (2011). CrossRef M.B. Saisudha, J. Ramakrishna, "Effect of host glass on the optical absorption properties of Nd3+, Sm3+, and Dy3+ in lead borate glasses", Phys. Rev. B 53, 6186 (1996). CrossRef C.K. Jayasankar, V. Venkatramu, S. Surendra Babu, P. Babu, "Luminescence properties of Dy3+ ions in a variety of borate and fluoroborate glasses containing lithium, zinc, and lead", J. Alloys Compd. 374, 22 (2004). CrossRef W.A. Pisarski et al. "Luminescence spectroscopy of rare earth-doped oxychloride lead borate glasses", J. Lumin. 131, 649 (2011). CrossRef M. Kochanowicz, W. Mazerski, J. Żmojda, K. Czajkowski, D. Dorosz, "Green upconversion emission in tellurite optical fibre codoped with Yb3+/Er3+", Phot. Lett. Poland 5, 35 (2013). CrossRef J. Dorosz, "Novel constructions of optical fibers doped with rare ? earth ions", Ceramics 86 (2005). CrossRef J. Żmojda, D. Dorosz, M. Kochanowicz, J. Dorosz, "Spectroscopic properties of Yb3+/Er3+ - doped antimony-phosphate glasses for fiber amplifiers", Phot. Lett. Poland 2, 76 (2010). CrossRef J. Dorosz, R. S. Romaniuk, "Development of Optical Fiber Technology in Poland", INTL J. Electron. Telecom. 57, 191 (2011). CrossRef Q.Y. Zhang et al. "Effects of PbF2 doping on structure and spectroscopic properties of Ga2O3?GeO2?Bi2O3?PbO glasses doped with rare earths", J. Appl. Phys. 99, 033510 (2006) CrossRef W.A. Pisarski, G. Dominiak-Dzik, W. Ryba-Romanowski, J. Pisarska, "Role of PbO substitution by PbF2 on structural behavior and luminescence of rare earth-doped lead borate glass", J. Alloys Compd. 451, 220 (2008). CrossRef M. Sołtys, J. Pisarska, L. Żur, T. Goryczka, W.A. Pisarski, "Influence of M2O3 (M = Al, Ga) glass modifiers on structure, thermal and spectroscopic properties of rare earth ions in lead phosphate based systems", Proc. SPIE 9228, 92280A (2014). CrossRef J. Janek, J. Pisarska, W.A. Pisarski, "Rare earth doped lead-free germanate glasses for modern photonics", Phot. Lett. Poland 6, 71 (2014). CrossRef W.A. Pisarski et al. "Infrared-to-visible conversion luminescence of Er3+ ions in lead borate transparent glass-ceramics", Opt. Mater. 31, 1781 (2009). CrossRef J. Pisarska, L. Żur, W.A. Pisarski, "Optical spectroscopy of Dy3+ ions in heavy metal lead-based glasses and glass?ceramics", J. Mol. Struct. 993, 160 (2011). CrossRef L. Żur, M. Sołtys, J. Pisarska, W.A. Pisarski, "Absorption and luminescence properties of terbium ions in heavy metal glasses", J. Alloys Compd. 578, 512 (2013). CrossRef W.A. Pisarski, L. Żur, M. Kowal, J. Pisarska, "Enhancement and quenching photoluminescence effects for rare earth ? Doped lead bismuth gallate glasses", J. Alloys Compd. 651, 565 (2015). CrossRef M. Shojiya, Y. Kawamoto, K. Kadono, "Judd?Ofelt parameters and multiphonon relaxation of Ho3+ ions in ZnCl2-based glass", J. Appl. Phys. 89, 4944 (2001). CrossRef

Experimental EPR results of 99.5%[x B2O3 (1-x) Bi2O3]0.5%MO glass samples (MO = MnO, Fe2O3 and 0.07 ≤ x ≤ 0.8) systems are presented. The resonance absorptions are centered at g ≈ 4.3 and g ≈ 2.0. For manganese-doped samples both lines show hyperfine structure for certain values of Bi/B ratio. In addition to these lines a well defined shoulder at g ≈ 9.8 is recorded from the samples doped with iron. The changes in matrix composition, corresponding to different values of x, induce changes in the surroundings of the resonance centers. Structural data obtained from the EPR measurements indicate various sites for Mn2+ and Fe3+ ions in environments characterized by different crystalline field intensities. The EPR data also provides evidence that the redox effect of bismuth–borate matrices on the doped paramagnetic ions is a function of Bi/B ratio.

This paper presents the results of research on the luminescent properties of antimony-borate glass rods doped with europium and silver ions. The reduction of silver ions to the form of nanoparticles was carried out and the occurrence of localized plasmon resonance was demonstrated, which caused changes in the Eu3+ luminescence signal at a wavelength of 613 nm. The effect of the concentration of silver ions dopant at a constant content of europium ions on the luminescence and absorption characteristics of the produced samples was investigated. In the examined doping range, no large dependencies of spectral changes as a function of the concentration of silver ions were found. A clear quenching of the luminescence was observed due to the heating time of the doped glass matrices for the energy transition (5D0 → 7F2). Full Text: PDF ReferencesS. Kuzman, J. Perisa, V. Dordevic, I. Zekovic, I. Vukoje, Z. Antic and M. D. Dramicanin, "Surface Plasmon Enhancement of Eu3+ Emission Intensity in LaPO4/Ag Nanoparticles", Materials 13, 3071 (2020). CrossRef V.P. Prakashan, M.S. Sajna, G. Gejo, M.S. Sanu, A.C. Saritha, P.R. Biju, J. Cyriac and N.V. Unnikrishan, "Surface Plasmon Assisted Luminescence Enhancement of Ag NP/NWs-Doped SiO2-TiO2-ZrO2:Eu3+ Ternary System", Plasmonics 14, 673 (2019). CrossRef O. Malta, P. Santa-Cruz, G. Sa and F. Auzel, "Fluorescence enhancement induced by the presence of small silver particles in Eu3+ doped materials", J. Lumin., 33, 261 (1985). CrossRef O. Malta, P. Santa-Cruz, G. Sa and F. Auzel, "Time evolution of the decay of the 5Do level of Eu3+ in glass materials doped with small silver particles", Chem. Phys. Lett, 116, 396 (1985). CrossRef J. Zmojda, M. Kochanowicz, P. Miluski et al., "The influence of Ag content and annealing time on structural and optical properties of SGS antimony-germanate glass doped with Er3+ ions", Journal of Molecular Structure 1160, 428 (2018). CrossRef Ki Young Kim, Plasmonics: Principles and Applications (Croatia, InTechOpen 2012) CrossRef M.R. Dousti, M.R. Sahar, S.K. Ghoshal et al., "Up-conversion enhancement in Er3 +-Ag co-doped zinc tellurite glass: Effect of heat treatment", Journal of Non-Crystalline Solids 358, 2939 (2012). CrossRef I. Soltani, S. Hraiech, K. Horchani-Naifer et al., "Effect of silver nanoparticles on spectroscopic properties of Er3+ doped phosphate glass", Optical Materials 46, 454 (2015). CrossRef R. Schneider, E.A. de Campos, J.B.S. Mendes, J.F. Felix, P.A. Santa-Cruz, "Lead–germanate glasses: an easy growth process for silver nanoparticles and their promising applications in photonics and catalysis", RSC Advances 7 (66), 41479 (2017). CrossRef

The samarium-doped lithium-gadolinium borate [60Li2O:10Gd2O3:(30-x) B2O3:xSm2O3] (LGBO:Sm3+) glasses have been melted and quenched in stainless plate under an air atmosphere. Some physical and optical properties within wavelength concerned and photoluminescence of the LGBO:Sm3+glasses were measured and discussed. The density of glasses dropped until 0.10 mol% and tends to increase after that point, while molar volume of the glasses tends to increase with concentration of Sm2O3.. In absorption spectra, there are 2 obvious peaks in UV-VIS range and 6 peaks in NIR range indicating the Sm3+in glass matrices. The sharpness of a peak, in the absorption spectra, also increases with concentration of the dopant. The 7 obvious peaks in excitation spectra represent the transitions from the ground state6H5/2to various excited states. Furthermore, The emission spectra were observed under 404 nm light from the Xenon compact arc lamps, and showed the concentration quenching effect (CQE) at 1.00 mol% of Sm3+. Additional, The lifetimes showed decreasing trend with concentration of Sm2O3.. As the result, The LGBO:Sm3+glass doped with 1.00 mol% of Sm3+gives the highest result for luminescence properties.

Melting and freezing of metallic nanoparticles embedded in glass matrices usually occur at temperatures lower than for the same metal in the bulk state.In situsmall-angle X-ray scattering (SAXS) measurements using a synchrotron beamline and a specially designed high-temperature chamber allowed the determination of the temperature dependence of the SAXS intensity produced by a dilute and nearly monodisperse set of spherical Pb nanoparticles, with an average radius 〈R〉 = 16.1 nm, embedded in a homogeneous lead–borate oxide glass. The temperature dependences of the nanoparticle volumeV(T) and nanoparticle radius of gyrationRg(T) derived from SAXS results exhibit clear discontinuities during the cooling and during the heating processes, thus allowing for precise determinations of the melting and freezing temperatures of the studied Pb nanoparticles. Additional features observed in bothV(T) andRg(T) curves showed that during the heating cycle the frozen Pb nanoparticles suffer a transition to a more compact phase at 433 K before melting at 580 K. The results of this work demonstrate that the melting and freezing temperatures of nanoparticles in a very diluted state – for which the X-ray diffraction technique is not sensitive enough – can be precisely determined by applying only the SAXS method.

In this work, total mass attenuation coefficients and effective atomic numbers of a series of three host glasses with different chemical composition, 65RmOn: 10CaO : 25Na2O mol% (where RmOnare B2O3, SiO2and P2O5, respectively) have been studied as a function of photon energy. The total mass attenuation coefficient values were taken from WinXCom program, were used to evaluate the effective atomic numbers in the energy range from 1 keV to 100 GeV. The obtained results for all samples are compared and discussed.

AbstractThe oxide glass–ceramics is a promising class of solid state materials because they are using thermally stable and chemically inert glass oxide matrices. Development of such efficient glass matrices suitable for creation of glass–ceramic materials for several purposes is an important practical task. The xLi2O–yV2O5–(100 − x − y)B2O3 undoped glass and 47Li2O–2V2O5–50B2O3–1La0.3Eu0.7VO4 glass samples with crystalline nanoinclusions were synthesized and investigated using XRD, IR and UV–Vis spectroscopy and UV band-to-band excitation of luminescence. The synthesized glass samples are characterized by wide band photoluminescence emission with maximum at 570 nm and intensity increased with increase of Li2O concentration. The excitation spectra consist of three bands with maxima located at 270, 320 and 365 nm. The observed concentration dependencies of spectral distributions in the absorption and excitation spectra are explained by influence of the lithium ions on a ratio between triborate and tetraborate groups in the glass networks. The assumption is made that the observed wide band photoluminescence emission of the glass matrix can appear as a result of recombination processes between the defects in borate networks and the broken vanadate groups. The crystalline component in the doped glass samples is found to not affect the luminescence properties of the glass matrix. Intensity of narrow band photoluminescence emission of the crystalline component is up to 10 times more intense than that of the glass matrix wide band emission. The synthesized type of the glass matrices has promising characteristics for the use of developed materials in lighting devices, as it allows improving the spectral distribution of light emission towards the white light.

AbstractBarium titanium borate glasses doped with ytterbium ions were fabricated via standard melt quenching technique. The building structure of the glass matrices doped with ascendant ratios of ytterbium ions were studied using Raman and FTIR spectroscopies. The UV–Vis–NIR optical absorption spectra were investigated and used to calculate optical bandgaps, Urbach energies, refractive indices, metallization criterion, optical basicity, and dispersion parameters. The absorption and emission cross-sections and gain spectra for 2F5/2 → 2F7/2 transition of ytterbium ions were investigated. The high values of the emission cross-sections of the studied glasses make them strong candidates for laser and amplifier applications.