Different concentrations of Pr
6
O
11
doped Sodium lead borophosphate (SLBP) glasses were synthesized and characterized using XRD (X-ray diffraction), DTA (differential thermal analysis), FTIR ...(Fourier transform infrared), absorption, emission and decay profiles. The thermal behaviour of the Pr
3+
ions doped sodium lead borophosphate glasses were explored DTA thermo-grams. FT-IR spectrum indicate the properties of BO
3
and PO
4
structural information. Based on the observed peak positions of the absorption spectra, the bonding parameter (δ) has been computed. From the absorption spectra various spectroscopic and lasing parameters were evaluated for various excited states of Pr
3+
ions. Various energy interaction parameters have been evaluated using this absorption data. The emission spectra of Pr
3+
ion in SLBPPr glasses exhibit four emission bands at 484, 526, 600 and 640 nm corresponding to the transitions
3
P
0
→
3
H
4
,
3
P
1
→
3
H
4,
1
D
2
→
3
H
4
and
3
P
0
→
3
F
2
, respectively. The SLBPPr glasses decay curves were measured using a 443 nm excitation and an emission peak at 602 nm as a monitoring tool. The decay cures indicate a non-exponential trend, with lifetimes shortening as praseodymium (III) ions concentration rises. The CIE (Commission International de I’Eclairage) chromaticity colour coordinates were also calculated to see if these glasses were suitable for visible red luminescence devices.
Spectroscopic properties of Sm3+ ions in phosphate based glasses (P2O5+K2O+Al2O3+CaF2) were investigated through SEM with EDS, X-ray diffraction (XRD), differential thermal analysis (DTA), Fourier ...transform infrared (FTIR), Raman, absorption, emission and decay measurements. Judd–Ofelt (JO) intensity parameters were obtained from the absorption spectrum which are inturn used to calculate the emission properties such as radiative transition probabilities (AR), radiative lifetime (τR), branching ratios (βR) and stimulated emission cross-sections (σe(λP)) for the 4G5/2→→6HJ (J=5/2,7/2,9/2 and 11/2) transitions of Sm3+ ions. The effective fluorescence bandwidth (Δλeff) and the experimental branching ratios (βexp) were determined from the emission spectrum. The decay profiles of 4G5/2 level exhibited non- exponential nature with the increase of Sm3+ ions concentration. The non-exponential behavior of decay curves has been explained by using the Inokuti–Hirayama (IH) model for S=6, which indicates that the energy transfer mechanism is dipole–dipole between the Sm3+ ions.
The lanthanide doped lead lithium calcium zinc fluoroborate glasses (LLCZFB:Ln) of composition 20PbF2+10Li2O+5Cao+5ZnO+59B2O3+1Ln2O3 (where Ln=Sm, Eu and Dy in mol%) were prepared by conventional ...melt quench technique. The amorphous nature of these glasses was confirmed by X-ray diffraction studies. The glass transition temperatures (Tg) were studied by DSC analysis. The glass structure and spectroscopic properties were investigated using optical absorption, vibrational and fluorescence spectra. The FT-IR spectra and Raman spectra reveal the presence of BO3, BO4 and non-bridging oxygen׳s. The Judd–Ofelt intensity parameters Ωλ (λ=2, 4, 6) were determined from the spectral intensities of absorption bands. These parameters were used to calculate the radiative parameters such as radiative transition probability (AR), radiative life time (τR) and branching ratio (βr) for various excited luminescent states of rare earth ions. The visible emission spectra for different rare earth ions were recorded by exciting the samples at different wavelengths and the decay rates for the different rare earth ions were measured. Using the emission spectra, full width half maxima (FWFM), stimulated emission cross section (σEp) were evaluated. The nature of decay profiles of 4F9/2, 4G5/2 and 5D0 states of Dy, Sm and Eu ions respectively are analyzed. Comparison of luminescence features of these glasses and also with those reported for different glass hosts indicates that the LLCZFB:Dy glass has strong luminescence in the visible region.
•LLCZFB:Ln glasses are prepared with Ln: Sm, Eu and Dy.•Glasses are characterized by XRD, FTIR, Raman, absorption and emission spectra.•J–O theory is used to calculate different radiative properties.•Green, yellow and red emissions are observed.•Glasses are useful for the development of visible luminescent devices.
In the present work, different concentrations of Sm3+ ions doped lithium zinc borate glasses (LBZnFSm: Li2CO3+H3BO3+ZnF2+Sm2O3) were prepared by melt quench technique. Thermal stability, amorphous ...nature and vibrational modes of lithium zinc borate glasses have been studied by using differential scanning calorimetry, X-ray diffraction and Fourier transform infrared spectroscopy, respectively. Spectroscopic characterization of Sm3+-doped lithium zinc borate glasses through absorption, excitation, emission and decay spectra has been carried out. Using absorption spectra nephelauxetic ratios, bonding parameters and energy band gap of the glass were evaluated. Judd–Ofelt (JO) intensity analysis had been performed and JO parameters were estimated for 1.0mol.% Sm2O3 doped lithium zinc borate glass. Radiative properties such as transition probabilities, branching ratios and radiative lifetime were estimated by using JO parameters. Stimulated emission cross-sections and effective bandwidths of each transition were obtained from the luminescence spectra. The decay curves of Sm3+-doped lithium zinc borate glasses exhibit single exponential nature for lower concentrations and gradually changes to non-exponential for higher Sm3+ concentrations. The experimental life time, quantum efficiency and donor acceptor interaction parameters were also estimated using decay curves of 4G5/2 level of Sm3+ ions in the present glasses. The non-exponential nature of the decay curves has been analyzed by Inokuti–Hirayama model indicating that ion interaction is of dipole–quadrupole nature. Dielectric studies of 0.1, 1.0 and 2.0mol.% Sm2O3-doped glasses were undertaken and dielectric constants, Cole–Cole parameters and power-law parameters were also determined.
•Sm3+ ions successfully incorporated in lithium zinc borate glass.•JO parameters of Sm3+:lithium zinc borate glass are tabulated.•Lifetimes are measured from decay curves.•Dielectric studies are discussed.
Neodymium doped phosphate based glasses with composition of (P2O5+K2O+Al2O3+CaF2) were prepared. The samples were analysed through differential thermal analysis (DTA), Fourier transform infrared ...(FTIR), absorption, emission and decay measurements. Judd-Ofelt parameters (Ωλ) have been determined from the spectral intensities of absorption bands in order to calculate the radiative parameters like radiative transition probabilities (AR), radiative lifetime (τR) and branching ratios (βR) for the 4F3/2→4I11/2 laser transition of Nd3+ ion. The effective emission bandwidths (Δλeff), experimental branching ratios (βexp) and stimulated emission cross-sections (σe) have been determined from the emission spectrum. The decay curves of the 4F3/2 level exhibited almost single exponential nature for all the Nd3+ ion concentrations.
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•Nd3+-doped phosphate based glasses were prepared by melt quenching method.•DTA-TGA analyses were carried out to know the thermal properties.•PL spectra and PL lifetime were recorded for all the samples at 1.06μm.•Nd3+-doped P2O5+K2O+Al2O3+CaF2 glasses with low OH content were prepared.•The obtained results are most favorable for 1.06μm laser application.
We report the fluorescence properties of samarium (III) ions in fluoro-borate glasses (Sm
3+
:BCNF) which were examined through X-ray diffraction, Fourier transform infrared, and UV–Vis–NIR ...spectroscopy. From the absorption spectra, Judd–Ofelt intensity parameters were determined, which are in turn used to evaluate several radiative properties for the various excited states of samarium (III) ions. The emission spectrum was used to calculate the effective bandwidth (Δ
λ
eff
) and empirical branching ratios (
β
exp
). With increasing concentrations of samarium (III) ions, the luminescence decay patterns of the
4
G
5/2
transition became double exponential. The Inokuti–Hirayama model for
S
= 6 has been used to explain the double-exponential behavior of decay time profiles, revealing that the energy transmission mechanism between the samarium (III) ions are dipole–dipole.
•Sm3+ ions successfully incorporated in zinc potassium fluorophosphate glass.•Physical properties are investigated.•JO parameters of Sm3+: zinc potassium fluorophosphate glass are ...tabulated.•Radiative properties are evaluated.•Lifetimes are measured from decay curves.
In the present work, different concentrations of Sm3+ ions doped zinc potassium fluorophosphate glasses (PKAMZFSm: P2O5+K2O+MgO+Al2O3+ZnF2+Sm2O3) were synthesized via melt quench technique. Physical properties and refractive indices of the present glasses were evaluated. Optical characterization of Sm3+: PKAMZF glasses through absorption, excitation, emission and decay spectra had been carried out. Nephelauxetic ratios, bonding parameter and energy band gap of the 1.0mol% Sm3+-doped PKAMZF glass were evaluated using absorption spectra. Judd–Ofelt (JO) intensity analysis had been presented and JO parameters were evaluated for 1.0mol% Sm3+-doped zinc potassium fluorophosphate glass. Radiative properties such as transition probabilities, branching ratios and radiative lifetime were estimated by using JO parameters. Stimulated emission cross-sections and effective bandwidths of each transition were obtained from the luminescence spectra. The experimental lifetime, quantum efficiency and donor–acceptor interaction parameters were also estimated using decay curves of 4G5/2 level of Sm3+ ions in the present glasses. The influence of Sm3+ ion concentrations on the luminescence intensity, lifetime and energy transfer parameters for PKAMZFSm glasses was investigated. The results obtained have been compared with the other Sm3+-doped glasses.
Phosphate glasses with compositions of 44P2O5 + 17K2O + 9Al2O3 + (30 − x)CaF2 + xDy2O3 (x = 0.05, 0.1, 0.5, 1.0, 2.0, 3.0 and 4.0 mol %) were prepared and characterized by X-ray diffraction (XRD), ...differential thermal analysis (DTA), Fourier transform infrared (FTIR), optical absorption, emission and decay measurements. The observed absorption bands were analyzed by using the free-ion Hamiltonian (HFI) model. The Judd–Ofelt (JO) analysis has been performed and the intensity parameters (Ωλ, λ = 2, 4, 6) were evaluated in order to predict the radiative properties of the excited states. From the emission spectra, the effective band widths (Δλeff), stimulated emission cross-sections (σ(λp)), yellow to blue (Y/B) intensity ratios and chromaticity color coordinates (x, y) have been determined. The fluorescence decays from the 4F9/2 level of Dy3+ ions were measured by monitoring the intense 4F9/2 → 6H15/2 transition (486 nm). The experimental lifetimes (τexp) are found to decrease with the increase of Dy3+ ions concentration due to the quenching process. The decay curves are perfectly single exponential at lower concentrations and gradually changes to non-exponential for higher concentrations. The non-exponential decay curves are well fitted to the Inokuti–Hirayama (IH) model for S = 6, which indicates that the energy transfer between the donor and acceptor is of dipole–dipole type. The systematic analysis of revealed that the energy transfer mechanism strongly depends on Dy3+ ions concentration and the host glass composition.
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•Dy3+-doped phosphate glasses were prepared by melt quenching method.•XRD, DTA analysis were carried out to know glassy nature and thermal properties.•Stimulated emission cross-section is higher for 4F9/2 → 6H13/2 transition of Dy3+ ion.•PKAlCaFDy glasses are useful to development of solid state lasers and w-LEDs.
A facile synthesis of novel α-aminophosphonates 5a-j was accomplished by condensation of imines (3a-j) with diethyl phosphite (4) in ethanol at 50-60°C using easily recoverable and reusable catalyst, ...tetramethyl guanidine (TMG) via pudovik reaction in high yields. All the title compounds were characterized by spectral and elemental analysis. They were further screened for their abilities towards in vitro antibacterial, antifungal and antioxidant activities. The compounds 5g, 5d, 5f exhibited good antibacterial and antifungal activities compared to the standard bactericide, Penicillin and fungicide, Griseofulvin, respectively. The compounds 5h, 5i, 5g, and 5c exhibited good antioxidant activity compared to the standard ascorbic acid.
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•Er3+:Li–Zn fluoroborate glass was fabricated for laser applications.•Judd–Ofelt and radiative parameters were investigated.•Broadband optical communications due to 1.5μm ...emission.•McCumber theory analysis for 1.5μm region.
Er3+-doped Li–Zn fluoroborate glass was synthesized via melt quenching technique. Optical properties of the glass were investigated by UV–Vis-NIR absorption and emission spectra. To evaluate the nature of Er3+-ligand bond in the glass network, nephelauxetic ratios and bonding parameter were calculated. Judd–Ofelt analysis and hence the radiative properties of the present glass system were evaluated for ascertaining the suitability of the glass for laser applications and compared those with the emission spectra. Absorption cross-sections have been calculated from the absorption spectrum and stimulated emission cross-sections were estimated using McCumber theory for 4I13/2↔4I15/2 transitions. The results of the present glass were compared with those obtained for some other Er3+-doped glass systems.
