Alumino Borosilicate Research Articles

Effect of Gd2O3 substitution for La2O3 on structure, physicochemical and electrical properties in aluminoborosilicate glasses for advanced microelectronics packaging

Currently, to develop new glass materials with lower dielectric constant (εr) and dielectric loss (tanδ), low coefficient of thermal expansion (CTE), excellent thermal stability and chemical stability for advanced microelectronics packaging has been significant pursuits of many researchers. In this work, novel 58SiO2-20B2O3-8Al2O3-10CaO-1Na2O-(3-x) La2O3-x Gd2O3 (x=0, 0.5, 1, 1.5, 2, 2.5 and 3 mol%) were successfully fabricated by the conventional melt annealing method. The results revealed that single addition of Gd2O3 or La2O3 (x=0, 3 mol%) strengthened glass network structure, which in turn improved performances of the glass. It was interestingly found that similar to the mixed-base effect, double-doped Gd2O3 and La2O3 played a greater role in improving glass structure and properties. The glass with x=1.5 mol% Gd2O3 exhibited the lowest dielectric permittivity, dielectric loss and low coefficient of thermal expansion (εr = 4.72, tanδ = 0.0004 (@1 MHz), CTE = 3.78 ppm/°C) and good chemical stability, which is optimal for the comprehensive performance compared with other aluminoborosilicate (Al-B-Si) glasses reported so far. These findings highlight that this glass is expected to be used in the microelectronics packaging field.

Efficient sorption and secure immobilization of strontium ions onto nanoporous alumino-borosilicate as a new matrix

The objective behind developing the nanoporous alumino-borosilicate (AlBS) was to remove strontium ion (Sr2+) from liquid waste and subsequently stabilize it. The sorption capacity of the nanoporous AlBS was assessed in relation to various experimental factors, including contact time, temperature, initial pH solution, and initial concentration of Sr ions. According to the obtained results, nanoporous AlBS shows a maximum Sr2+ sorption capacity of 163.08 mg/g. In order to achieve stable immobilization of the sorbed Sr ions, heat treatments at different temperatures were applied to the Sr-containing nanoporous AlBS. Various eluents were used in the leach tests to examine the Sr ions leaching from heat-treated materials. Only 3.43% of the Sr ions initially adsorbed in the nanoporous AlBS matrix was washed out with 1 M sodium chloride eluent, showing that heating the sample to around 1100 °C successfully trapped Sr ions in the nanoporous AlBS matrix.

Fracture toughness of Ca‐, Sr‐, and Ba‐aluminoborosilicate glasses

AbstractThe field strength effect on fracture toughness was tested for three alkaline earth (AE) aluminoborosilicate (ABS) glasses. This work explores the impact of modifier field strength (FS) on macro‐mechanical properties in line with previous works which examined the FS effect on structure, hardness, crack resistance, and elastoplastic properties of alkali and AE‐ABS glasses. Fracture toughness (KIcVNB) was found to increase as modifier FS increased; and the elastoplastic ratio (HV/E) correlated well with plasticity, hardness, and fracture toughness. The purpose of this work is to examine the mechanical response of AE‐ABS glasses at a larger length scale in order to determine whether the field strength effect is active as was observed at lower length scales in previous works. The observed increase and decrease of the KIcVNB and HV/E, respectively, with increasing modifier FS, suggest a strong correlation between increasing fracture toughness and crack resistance with increasing plasticity for the AE‐ABS glasses studied.

The role of ZrO2 as glass-network former on radiation transmission properties of aluminoborosilicate (ABS) glasses: A glass type for nuclear waste immobilization

We report the gamma-ray shielding properties, transmission factors and, effective removal cross section values of several aluminoborosilicate glasses that have been synthesized through various glass-forming materials such as Al2O3, B2O3, SiO2, and ZrO2. The study utilized the elemental compositions and densities of eight different glass samples as input variables in theoretical calculations and Monte Carlo simulations. According to the results obtained, it was seen that the network-forming type used in aluminoborosilicate glasses had a direct effect on the radiation absorption properties of the glasses. The utilization of ZrO2 and Cs2O at the highest concentration as the network former and glass network modifier in the NCBZ-6 sample yielded the most advantageous results in relation to its gamma-ray absorption capabilities. The benefit is intrinsically related to the heightened density of glass and the incorporation of compounds with increased atomic numbers, both of which are fundamental characteristics desired in materials designed for the purpose of gamma-ray absorption. However, the enhanced capability of ZrO2 to absorb gamma-rays excludes the absorption of high-energy neutrons. The absence of boron trioxide (B2O3) in the NCBZ-6 sample can be ascribed to its restricted availability against fast neutrons. The continued existence of ZrO2 as a network forming in the investigated ABS glasses is likely to result in improved material homogeneity and progressive enhancement of gamma-ray absorption characteristics. It can be concluded that the incorporation of ZrO2 as a network-former component may be an appropriate strategy to enhance the gamma-ray shielding capabilities of aluminoborosilicate glasses.

Field strength effect on elastoplastic behavior of aluminoborosilicate glass: I. Elastic moduli and indentation size effect

AbstractThe modifier field strength (FS) is believed to play an important role in determining the elastic–plastic responses of aluminoborosilicate (ABS) glasses, but its effect is not well understood. Three novel alkali and three alkaline earth (AE) ABS compositions were created for this study which is the first part of two studies that explored the elastoplastic responses of these glasses. Six compositions were designed using different network modifiers (NWMs) to cover a range of cation FS. The glasses were also designed such that the concentrations of NWM and Al2O3 were similar, which maximized the three‐coordinated boron fraction in the network. It is well known that modifier FS can affect the coordination number (CN) of Al and B in an ABS glass structure, for example, a higher FS modifier can promote B3 → B4 and higher [Al5,6], but the degree of this depends on network former (NWF) ratios. Previous work used solid‐state NMR spectroscopic analysis on the current glasses to find that there was variation between [B4] and [Al4] between the two glass series (alkali vs. AE) but that was attributed to synthesis factors and no trend with FS was associated with the varying NWF CN. Further, 29Si ssNMR showed no evidence of NBOs which made sense based on composition. The conclusion, therefore, was that there was a far greater correlation with modifier FS for the increased mechanical and physical properties rather than the CN of Al and B. Part I of the current work focused on the elastic moduli, Poisson's ratio, the indentation size effect (ISE), and the bow‐in parameter. This part laid out the foundation to investigate the intersection of these elastoplastic properties with hardness and crack resistance as a function of NWM FS. Results showed that: (i) the Young's, bulk, and shear moduli increased with modifier FS, whereas Poisson's ratio did not trend with FS; (ii) the alkali glasses had a significantly higher magnitudes of ISE compared to the AE glasses; and (iii) the bow‐in parameter was load dependent and decreased with modifier FS at the highest indentation load.

Thermally stable Sm3+ -doped alkali zinc alumino borosilicate (AZABS) glass for warm white light generation and w-LED applications.

Samarium ion (Sm3+ )-doped alkali zinc alumino borosilicate (AZABS) glass was synthesized via quick melt quench technique. Various spectroscopic studies like optical absorption, photoluminescence (PL) emission, PL excitation, temperature-dependent PL and PL decay kinetics were performed on the as prepared glass system. Under 402 nm excitation, three sharp bands at wavelengths 563, 599 and 645 nm corresponding to transitions 4 G5/2 → 6 H5/2 , 6 H7/2 and 6 H9/2 , respectively, can be seen in the PL emission spectra. The 0.25 mol% Sm3+ glass has the highest intensity for these emissions. The lanthanide interaction in the glass matrix is dipole-dipole in nature as was proven from Dexter's analysis. The direct bandgap of 0.25 mol% Sm3+ -doped AZABS glass was calculated to be 2.88 eV. The lifetimes of the as prepared glass range from 1.93 ms for the lowest concentration of Sm3+ to 0.75 ms for the highest. From temperature dependent PL studies, the activation energy for 0.25 mol% Sm3+ -doped AZABS glass was found to be 0.19 eV which shows high thermal stability of this glass. We propose to utilize these Sm3+ -doped AZABS glasses for white-light emitting diodes (w-LEDs) and solid-state lighting (SSL) applications.

Photoluminescence and energy transfer studies on Tm3+/Dy3+/Eu3+doped borosilicate glasses for color tunability and warm white light generation

Potassium Zinc Alumino Borosilicate (KZABS) glasses doped with Dy3+, Tm3+ and Eu3+ have been prepared by a quench melting technique. The glasses show characteristic blue (1D2 → 3F4) and yellow (4F9/2 → 6H13/2) emission bands under 362 nm excitation. To produce warm white light, a red component was required in luminescence for which Eu3+ ions were added to the KZABS glass. A red emission (5D0 → 7F2) was seen under 362 nm excitation along with the blue and yellow bands. Photoluminescence (PL) studies show energy transfer from Tm3+ and Dy3+ ions to Eu3+ ions. The average lifetimes of the tri-doped glasses for all emission wavelengths decrease with increasing concentration of Eu3+ions. CIE chromaticity study also proves that tri-doped KZABS glasses can generate warm white light. Thus, we propose to use KZABS: Tm3+/Dy3+/Eu3+ glasses for warm white light generation in solid-state lighting (SSL) and white light emitting diode (w-LED) applications.

Field strength effect on structure, hardness, and crack resistance in single modifier aluminoborosilicate glasses

AbstractAlthough the interactions among glass formers and modifiers, for example, connectivity and charge distribution, have been studied extensively in oxide glasses, the impact of a particular modifier species on the mechanical performance of aluminoborosilicate (ABS) glasses is not well understood. This work compares the indentation properties of six ABS glasses, each of which contains a different network modifier (NWM) with varying field strength (FS). Three alkali and three alkaline earth ABS glasses were designed with low NWM content and [NWM] ≈ [Al2O3], to test the modifier FS effect at low concentrations and to maximize three‐coordinated boron. It has been found that both hardness and crack resistance increase with increasing FS in these ABS systems, which is surprising in the context of historical reports. Using 11B, 27Al, and 29Si solid‐state nuclear magnetic resonance, this work provides evidence of how charge distributions differ as a function of NWM species, and how this relates to the observed indentation behaviors.

Tunable photoluminescence studies of KZABS: RE3+ (RE3+ = Tm3+, Tb3+ and Sm3+) glasses for w-LEDs based on energy transfer

Here singly and tri-doped (Tm3+, Tb3+, and Sm3+) borosilicate glasses in potassium Zinc alumino borosilicate (KZABS) glasses were prepared by using the melt quenching technique. The tri-doped as-prepared KZABS glasses were characterized through photoluminescence (PL) emission and PL decay to demonstrate red (Sm3+), green (Tb3+) and blue (Tm3+) colors simultaneously and white light realization by varying the Sm3+ ion concentration under 356 nm excitation. The energy transfer mechanism from Tm3+ to Tb3+ (1G4 to 5D4), Tm3+ to Sm3+ (1G4 to 4G7/2), and Tb3+ to Sm3+ (5D4 to 4G7/2) are confirmed by the lifetime values. The I–H model fitted with non-exponential decay curves reveals the dipole-dipole interaction. The temperature-dependent PL (TDPL) measurement and corresponding CIE points demonstrate the thermal stability of the as-prepared glasses. CIE coordinates and CCT values were observed near the standard white light (0.333, 0.333, and 5500 K). The results obtained reveal that Tm3+/Tb3+/Sm3+ tri-doped KZABS glasses could be a potential candidate for the fabrication of visible RGB luminescent materials, display devices and w-LEDs.

Enhancement of dysprosium oxide doped zinc alumino borosilicate glasses in thermal, optical and luminescence domain for solid state lighting application

Zinc alumino borosilicate (ZABS) glasses incorporated with Dy3+ ions are prepared through melt-quenching technique. Non-crystallinity behaviour of the glasses are confirmed through XRD studies. The presence of functional and vibrational groups in the glass network are witnessed through FTIR studies. From the differential thermal analysis (DTA), the thermal stability of the glasses are found to be greater than 90 °C. UV–Visible–NIR spectra of glasses showed strong absorptions of Dy3+ ions in the NIR region (∼1267 nm). The highest bandgap value is obtained for ZABSDy0.5 (4.27 eV) glass that has the lowest amount of non-bridging oxygens. The ionic nature of dysprosium ions in the glass vicinity is thereby known through bonding parameter calculation. Judd-Ofelt (J-O) intensity parameters showed the trend Ω2 > Ω6 > Ω4, maintained same for all synthesized glasses. The luminescence spectra showed three emission peaks of Dy3+ ions at 482 (6H15/2), 575 (6H13/2) and 663 (6H11/2) nm. The hypersensitive transition observed at 4F9/2 → 6H13/2 exhibits a greater emission cross-section and radiative transition for all the glasses. Through the decay measurements, the lifetime of the Dy3+ ions are calculated. The estimated CIE coordinates for the glasses showed their location in white light region. The correlated colour temperature (CCT) values are obtained between 4200 and 4500 K suggesting the importance of glasses to use for white-LEDs application.

Reddish-orange emissions from Sm3+ doped zinc alumino borosilicate glasses: A correlative study on structural, thermal, and optical properties

The present study investigates the structural, thermal, and optical properties of Sm3+-doped Zinc Alumino Borosilicate (ZABS) glasses obtained through the melt-quenching method. The prepared glasses clearly exhibit an amorphous nature confirmed by XRD analysis. Through FTIR studies, the vibrations of metal cations, B2O3, SiO2, Al2O3 network groups and OH groups were analysed. This study helps to determine the bridging and non-bridging oxygen quantity in glass structures including Sm2O3. Through differential thermal studies, the thermal stability factor and its related calculations were carried out. Glasses showed a thermal stability (ΔT) value > 100 °C. Absorption spectra of the glasses showed thirteen peaks emerged from the lower ground state 6H5/2. The bonding parameter calculation showed that the glasses exhibit ionic bonding. The Judd-Ofelt (J-O) parameters followed the same trend Ω4 >Ω2> Ω6 for the synthesized glasses. The bandgap values of the glasses decrease with higher content of NBOs in the glass network, and the Urbach energy (EU) increases. The luminescence spectra of the glasses show four emission peaks such that the intense emission is seen at transition 4G5/2 → 6H7/2 at 599 nm. The radiative parameters calculation showed that Sm3+- 0.5 mol% glass has a higher emission cross section (σse) and transition probability (AR). Decay curves were recorded for all the glasses that show single exponential behavior with extended lifetimes (ms). Glasses produce reddish-orange emissions under 402 nm excitation and the values of correlated color temperature (CCT) lie in the range of 1500–1600 K. Overall, the prepared Sm3+-doped ZABS glasses act as a good candidate for luminescent display applications and laser materials.

Color tunable photoluminescence in KZABS: Tm3+ glasses under different sources of excitation for photonic applications

Potassium Zinc Alumino Borosilicate (KZABS) glasses doped with Tm3+ ions have been prepared by using a melt quenching process and further investigated through various spectroscopic tools such as optical absorption, photoluminescence (PL) excitation, PL emission, and PL decay measurements. The non-crystalline nature of the as-prepared glasses was confirmed by XRD measurements. PL spectral properties show blue and red colors under different excitation wavelengths. The absorption spectrum recorded in the UV-Vis-NIR range reveals the high bandgap energy. The Inokuti-Hirayama (I-H) model well fitted to non-exponential decay curves confirms the energy transfer between Tm3+-Tm3+ ions as dipole-dipole in nature. Under 359 and 466 nm excitation wavelength the titled glasses are showing CIE coordinates falling in deep blue and deep red color, respectively. A good color tunability can be seen from the blue to the red region under different excitation wavelengths. All the studies finally reveal the superiority of Tm3+ doped KZABS glasses for their usage in blue/red-emitting photonic devices needed to fabricate photonic devices such as w-LEDs.

Photoluminescence characteristics of Sm3+/Eu3+ co-doped LPZABS glasses for solar cell applications

A series of Sm3+/Eu3+ co-doped LPZABS (lithium lead zinc alumino borosilicate) transparent glasses were synthesized by the melt quench method. Fluorescent characteristics and energy transfer mechanisms were analyzed thoroughly. The amorphous nature of the glasses was confirmed from the observed X-ray diffraction patterns. An expansion in photoluminescence (PL) excitation of Eu3+ ions was observed on sensitizing it with Sm3+ ions in the title compounds. The PL emission spectra obtained for different excitations show bands due to Sm3+ and Eu3+ ions with increment in intensity on increasing Eu3+ ion concentration. On implementing the Dexter energy transfer formula & Reisfeld's approximation to PL emission spectra and the Inokuti-Hirayama (I–H) model to PL decay profiles, the dipole-dipole interaction among activator and sensitizer is revealed. Chromaticity coordinates (CIE) gradually relocate from the orange to the red region on increasing Eu3+ ion concentration in Sm3+/Eu3+ co-doped LPZABS glasses. The Sm3+/Eu3+ co-doped LPZABS glasses have the potential for downshifting of n-UV & blue exciting photons into visible red color photons which make it useful for copper phthalocyanine (CuPc) solar cell applications.

Energy transfer dynamics in thermally stable Sm3+/ Eu3+ co-doped AEAlBS glasses for near UV triggered photonic device applications

Transparent, Sm3+/Eu3+ co-doped alkaline earth alumino borosilicate (AEAlBS) glasses have been synthesized by employing melt quenching process and explored their down-shifting luminescent properties to understand their utility in visible red photonic devices applications. The amorphous (non-crystalline) nature of the as-prepared glasses was analyzed with help of an X-ray powder diffraction (XRD) pattern, containing a broad peak. Photoluminescence (PL) properties demonstrate that the glasses can be proficiently excited by near-UV with a dominant peak centered at 402 nm. The PL emission spectra exhibit four emission peaks with an intense peak placed at 599 nm under 402 nm excitation. The optimum emission intensity was obtained for 0.5 mol% Sm3+ ions doped in AEAlBS glasses. In the present work, Sm3+ ion is acting as an effective sensitizer for Eu3+ activator in AEAlBS glasses, and part of energy gets transferred from sensitizer (Sm3+) to activator (Eu3+) ions. The PL intensity of Eu3+ ions is increasing at the expense of a decrease in the intensity of Eu3+ ion peaks in the co-doping AEAlBS glasses at λex = 402 nm. The efficient ET from sensitizer to activator ions proved to be dipole-dipole in nature via employing Dexter's formula with Reisfeld's approximation. The experimental lifetime values calculated from the PL decay profiles are decreasing with the surge in Eu3+ ion concentration in the as-prepared glasses. Inokuti Hirayama (I-H) model applied to the PL decay profiles confirms the ET process responsible for a decrease in experimental lifetimes as dipole-dipole in nature. The outcome of the I-H model is in consonance with the result given by Dexter theory. The CIE coordinates for single Sm3+ doped glasses are falling in the orange region and gradually surge into the red region by co-doping with Eu3+ ions in AEAlBS glasses. The temperature-dependent emission analysis reveals that the PL intensity at 150 °C and 200 °C perseveres up to 94.34 and 91.30% of the PL intensity at ambient temperature, respectively. All the obtained results contemplate the superiority of the multifunctional Sm3+/Eu3+ co-doped AEAlBS glasses for near UV triggered photonic device applications.

Downshifting analysis of Sm3+/Eu3+ co-doped LiBiAlBSi glasses for red emission element of white LEDs

The Sm3+, Eu3+ single doped, and Sm3+/Eu3+ co-doped lithium bismuth alumino borosilicate (LiBiAlBSi) glasses were prepared by using the melt quenching method and studied photoluminescence (PL) excitation, PL emission, and PL decay to have a better insight into their utility as red emission element for white LEDs. Sm3+ doped LiBiAlBSiSm05 glasses exhibit admirable emission features in the reddish-orange region under n-UV excitation (402 nm). Sm3+/Eu3+ co-doped LiBiAlBSi glasses can be adeptly excited by the blue and n-UV region which is confirmed from the excitation spectrum. In the Sm3+/Eu3+ co-doped LiBiAlBSi glasses, the PL decay lifetime for the Sm3+ emitting level (4G5/2) declines and the energy transfer efficiency increases with an upsurge in Eu3+ ion content, which suggests the energy transfer (ET) process occurs from Sm3+ to Eu3+ ions. The ET process from Sm3+ to Eu3+ ions is also suggested by Dexter's ET method and Reisfeld's approximation by using emission spectra due to non-radiative dipole-dipole (d-d) interaction. The calculated values of CIE chromaticity coordinate for the as-prepared glasses under n-UV excitation shifted from reddish-orange to the red spectral part with the upsurge in Eu3+ concentration. The temperature-dependent PL studies of the optimized LiBiAlBSiSE10 glass revealed its superior thermal stability. All the results obtained finally suggest that, the Sm3+/Eu3+ co-doped LiBiAlBSi glass with 0.5 mol% of Sm3+ ions and 1.0 mol% of Eu3+ ions is a thermally stable candidate to produce intense red color needed to fabricate white LEDs under n-UV and blue excitation through the downshifting process.

Influence of Tb3+ ions concentration and temperature on lithium bismuth alumino borosilicate glasses for green photonic device applications

Lithium bismuth alumino borosilicate (LiBiAlBSi) glasses doped with various concentrations of trivalent terbium (Tb3+) ions were prepared to explore their physical, optical, and photoluminescence (PL) characteristics features. Diffraction pattern recorded for an undoped as well as doped (1.5 mol% of Tb3+) LiBiAlBSi glass ascertained the amorphous nature. Absorption spectra reveal several peaks in n-UV and blue regions. The indirect optical band gap for Tb3+ doped LiBiAlBSi glasses was found in the 3.16-3.46 eV range. PL measurements such as emission (under 378 nm excitation) and excitation (under 542 nm emission) were recorded to study the usage of the as-prepared glasses for green photonic device applications. PL emission spectra reveal four emission bands of Tb3+ ions originating from the excited level of 5D4 to 7FJ (=3,4,5,6) levels. The intensity of the emission peak observed in the green region at 542 nm (5D4→7F5) escalates up to 1.5 mol% of Tb3+ ion concentration and declines beyond due to concentration quenching. Dexter theory applied to the PL emission spectral features reveals dipole-dipole interaction among Tb3+ ions responsible for the transfer of energy and thereby concentration quenching. The CIE coordinates and CCT values calculated for the as-prepared glasses are closure to the values of intense green emission given by the European Broadcasting Union illuminant. The experimental lifetime values (τexp) measured for the intense green emission (5D4→7F5) are reducing with the upsurge in the content of Tb3+ ions in the titled glasses. Correlation of τexp values with the PL emission spectral data facilitate the estimation of radiative properties. Relatively high activation energy value estimated from the temperature-dependent PL show the thermal stability of the optimized glass. The PL (excitation, emission, decay, temperature-dependent) studies along with colorimetric studies confirm the aptness of the LBiAlBSiTb15 glass for photonic applications such as laser and tricolour w-LEDs as a green emitting component.

Effective energy transfer from Dy3+ to Tb3+ ions in thermally stable KZABS glasses for intense green emitting device applications

Potassium Zinc Alumino Borosilicate (KZABS) glasses co-doped with Dy3+/Tb3+ ions have been synthesized by employing a sudden melt quenching technique. To check the luminescence behavior, the as prepared glasses were characterized by employing spectroscopic tools like photoluminescence (PL) excitation and emission, temperature dependent PL and PL decay to see the energy transfer between Dy3+ and Tb3+ ions and optimum green emission suitable for photonic applications. The XRD spectra reveals the amorphous nature of the as prepared KZABS glasses. PL spectral features show optimum green emission and confirms energy transfer from Dy3+ to Tb3+ ions. With the help of temperature dependent PL, glasses were found to be thermally stable. The decay profiles recorded show bi-exponential nature and demonstrates the energy transfer that took place from Dy3+ to Tb3+ ions. The Inokuti- Hirayama (I–H) model confirms the interaction involved in energy transfer process as dipole-dipole in nature. The CIE coordinates are found to be shifting gradually towards intense green region with increase in activator concentration (Tb3+) under the optimized sensitizer (Dy3+) concentration. It is also observed that, the CIE coordinates shifting towards intense green region when the as prepared KZABS glasses are excited with suitable excitation wavelengths of both sensitizer and activator. All the studies finally reveal the superiority of Dy3+/Tb3+ co-doped KZABS glasses for their usage in green emitting photonic device applications such as w-LEDs and display devices.

Monte Carlo simulation on shielding properties of neutron-gamma from 252Cf source for Alumino-Boro-Silicate glasses

Neutron-gamma attenuation characteristics of the Alumino-Boro-Silicate (ABS) glasses were estimated based on MCNPX simulation and theoretical calculations. The watt fission distribution was used to extract the neutron spectrum and the obtained results were reported in the presence and absence of the glass sample. The other attenuation parameters such as effective removal cross section (ΣR), mass removal cross section (∑Rρ), Half Value Thickness (HVT), Tenth Value Thickness (TVT), and also mean free path (mfp) were also demonstrated. The received data depicts that glass coded ABS-0 is an appropriate material in terms of neutron attenuation purposes in comparison to the other selected shielding materials. Moreover, it can be figured out that the increment of the Bi2O3 rate decreases the neutron shielding ability of the Alumino-Boro-Silicate glass and has a negative effect on the fast neutron shielding proficiency. Besides, using Doppler Effect gamma spectrum for spontaneous fission 252Cf source were extracted in shielding materials, and data represented graphically. Linear attenuation coefficient(μ), HVT, mfp for a wide energy range of incident gamma rays were also estimated. The simulated results showed that the ABS-4 glass sample possesses the highest μ value (better gamma shielding efficiency) which varies in the range between 0.381763 and 0.954323 cm−1 while the lowest μ value is obtained for ABS-0 that varies in the range between 0.339447 and 0.511594 cm−1.

Concentration-dependent reddish-orange photoluminescence studies of Sm3+ ions in borosilicate glasses

Abstract This paper elucidates the concentration-dependent photoluminescence properties of samarium ions in Lithium bismuth alumino borosilicate (LiBiAlBSi) glasses using XRD, FT-IR, absorption, excitation, emission & decay to quantify the luminescence properties of the titled glasses. XRD and FT-IR spectral data ascertain the non-crystalline nature and vibrational energies in host glass respectively. The intense excitation band observed at 400 nm in near UV region (under λem = 600 nm) is employed to read the emission spectra. Under 400 nm intense excitation wavelength, the titled glasses show intense visible reddish-orange emission at 600 nm. From the emission spectra, it is observed that 0.5 mol% of Sm3+ ions concentration in LiBiAlBSi glass is optimum for reddish-orange emission. The CIE coordinates estimated for LiBiAlBSi glasses are in good proximity with the reddish-orange emission coordinates specified by Nichia Corporation. Branching ratios, emission cross-sections, quantum efficiency, and CIE coordinates estimated finally reveals the aptness of the LiBiAlBSi glasses for reddish-orange optoelectronic device applications.

White Light Generation in Dy3+-Doped Sodium Lead Alumino Borosilicate Glasses for W-LED Applications

Excitation and emission spectra of sodium lead alumino borosilicate glass doped with different concentrations of Dy3+ have been reported. The concentration of Dy3+ were varied from 0.5 to 1.5 mol%. As a result of 385 nm excitation wavelength, the luminescence spectra showed three characteristic bands at 482 nm and 575 nm and 665 nm. These absorption bands were attributed to 4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 transitions respectively of Dy3+ ions. 4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 transitions respectively of Dy3+ ions. The yellow to blue intensity ratio increases (1.063 to 1.093) with increase in Dy3+ ion concentration. The decay rates exhibit single exponential for lower concentrations and turns into non exponential for higher concentrations. The non-exponential nature of the decay rates is well-fitted to the Inokuti-Hirayama model for S = 6, which indicates that the nature of the energy transfer between donor and acceptor ions is of dipole-dipole type. The lifetime for the 4F9/2 level of Dy3+ ion decreases (0.634 to 0.580 ms). The chromaticity coordinates have been calculated from the emission spectra and analyzed with Commission International de I’Eclairage diagram. The chromaticity coordinates visible in the white light region for all concentrations of Dy3+ ions in the present glasses. The correlated color temperature value varies from 5107 to 5362 K (closer to the day light value of 5500 K). These results indicate that Dy3+-doped sodium lead alumino borosilicate glasses can be development of white light emitting diodes and suitability for solid state lasers applications.