Influence of Dy3+ in physical and optical behavior of calcium sulfate ultra-phosphate glasses

To examine the influence of trivalent dysprosium ion (Dy3+) on physical and optical properties prepared by melt quenching method. The samples composition of 20CaSO4 (80 - x) P2O5 - xDy2O3, where x = 0.1, 0.2, 0.3, 0.4 and 0.5mol% were prepared and analyzed. Materials were characterized by X-ray diffraction, UV visible and photoluminescence spectroscopy, amorphous nature of the samples was confirmed by X-ray diffraction technique, UV-Vis for optical measurement and luminescence for excited state dynamics. The UV absorption spectra of the glass sample correspond to 6H11/2 (1673 nm), 6H9/2 (1262 nm), 6F9/2(1087 nm), 6H5/2 (899 nm), 6F5/2 (796 nm), 6F3/2 (753 nm), 6G11/2 (422), 4I13/2 (384) and 6P7/2 (347).The physical properties comprise of glass density, molar average molar volume, ion concentration, dielectric constant and molar refractive index was determined. The band gap (Eopt), Urbach energies (ΔE) and refractive index lie in range and decreases with increase in Dy3+ concentration. Therefore, Dy3+ compositional changes were examined and indicate that dysprosium phosphor could serves as a potential candidate for optical application as laser is included

Physical, optical and radiative properties of CaSO4–B2O3–P2O5 glasses doped with Sm3+ions

Trivalent rare earth ions doped borosulfophosphate glasses are in high demand owing to their several unique attributes that are advantageous for applications in diverse photonic devices. Thus, Sm3+ ion doped calcium sulfoborophosphate glasses with composition of 25CaSO4–30B2O3–(45−x)P2O5–xSm2O3 (where x = 0.1, 0.3, 0.5, 0.7 and 1.0 mol%) were synthesized using melt-quenching technique. X-ray diffraction confirmed the amorphous nature of the prepared glass samples. Differential thermal analyses show transition peaks for melting temperature, glass transition and crystallization temperature. The glass stability is found in the range 91 °C to 116 °C which shows increased stability with addition of Sm2O3 concentration. The Fourier transform infrared spectral measurements carried out showed the presence of vibration bands due to P–O linkage, BO3, BO4, PO4, P–O–P, O–P–O, S–O–B, and B–O–B unit. Glass density showed increase in value from 2.179 to 2.251 g cm−3 with increase in Sm2O3 concentration. The direct, indirect band gap and Urbach energy calculated were found to be within 4.368–4.184 eV, 3.641–3.488 eV and 0.323–0.282 eV energy ranges, respectively. The absorption spectra revealed ten prominent peaks centered at 365, 400, 471, 941, 1075, 1228, 1375, 1477, 1528 and 1597 nm corresponding to 4D3/2,6H5/2→4I11/2,6P3/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6F1/2 transitions respectively. Photoluminescence spectra monitored at the excitation of 398 nm exhibits four emission bands positioned at 559, 596,643 and 709 nm corresponding to 4G5/2→6H5/2, 6H7/2, 6H9/2 and 6H11/2 transitions respectively. The nephelauxetic parameters calculated showed good influence on the local environment within the samarium ions site and the state of the Sm–O bond. The Judd–Ofelt intensity parameters calculated for all glass samples revealed that Ω6> Ω4> Ω2. The emission cross-section and the branching ratios values obtained for 4G5/2→6H7/2 transition indicate its suitability for LEDs and solid-state laser application

Samarium doped calcium sulfate ultra-phosphate glasses: Structural, physical and luminescence investigations

Luminescence mechanism of RE doped glasses is significant in optical devices, the glasses of compositions (80-x) P2O5-20CaSO4-(x) Sm2O3 with 0.3 ≤ x ≤ 1.5 mol% have been prepared by melt-quench method. The result of XRD patterns affirmed the amorphous nature of the samples. The structure was investigated successfully using FTIR, NMR and Raman in order to examine the molecular vibrational modes and to verify the de-polymerization process. Absorption and photoluminescence spectra of Sm2O3 doped calcium ultra-phosphate glasses have been reported. Three emission band of Sm3+ centered at 4G5/2→6H9/2 (642 nm), 4G5/2→6H7/2 (597 nm) and 4G5/2→6H5/2 (559 nm) have been observed at λexc = 402 nm. The spectroscopic research reveals the de-polymerization pattern in P2O5 glass structure by conversion of Q3→Q2→Q1 and to Qo units. Physical and optical properties were investigated, doped ions were successfully position at interstice spaces in CSP, the physical properties such as, density, Polarizability, Molar refractivity, and refractive index etc, have been estimated. The absorption spectra in the wavelength range 900–1700 nm were determined, the spectra consist of seven absorption peaks corresponds to transitions from 6H5/2 ground state to excited state. From the absorption edge spectra, the band gap (direct and indirect) and the Urbach energy (ΔE) values were evaluated. The conventional JO (Judd-Ofelt) intensity parameters (Ω2, Ω4 and Ω6) and root mean square (δrms) deviation have been evaluated and discussed with respect to Sm3+ concentration. Obtained result goes along with the Sm3+ doped magnesium zinc sulfo-phosphate glasses for advancement of many functional glasses

Impact of Eu3+ on the luminescent, physical and optical properties of BaSO4 – B2O3 – P2O5 glasses

The investigations of the impact on the luminescent, physical and optical properties of Alkaline earth metal borophosphate glasses doped with rare earth (RE) ions became demanding owing to their several distinct features that are advantageous for applications in diverse photonic devices. A new series of BaSO4 – B2O3 – P2O5 glasses doped Eu3+ with different compositions of 25BaSO4 – 30B2O3 – (45-x) P2O5 – xEu2O3 (where x = 0.1, 0.3, 0.5, 0.7, 1.0, 2.0 and 2.1 mol%) were prepared by melt – quenching technique. X-ray diffraction and scanning electron microscope examined the amorphous state of the prepared glasses. Differential thermal analyser was used to determine the transition peaks. Some of their physical properties have been calculated. The direct band gap, indirect band gap and urbach energy were found to be within (4.654–4.199 eV), (3.902–3.656 eV) and (0.576–0.428 eV). The absorption spectra in the UV–vis and near infrared region revealed seven prominent peaks centred at 379, 393, 414, 463, 532, 2091 and 2206 nm corresponding to 7F0 → 5G2, 5L6, 5D3, 5D2, 5D1, 7F0 → 7F6 and 7F1 → 7F6 transitions respectively. Photoluminescence spectra monitoring at the excitation of 391 nm exhibits four emissions band positioned at 591, 613, 655 and 701 nm corresponding to 5D0 → 7F1, 7F2, 7F3 and 7F4 transition of Eu3+ ions. Judd-ofelt parameters have been calculated. The decay time of 5D0 level decreases from 2.02 to 1.52 ms. The excellent features demonstrated by the current glasses affirm their suitability for solid state lasers and red LEDs applications

Spectroscopic behaviour of Dy3+ and Sm3+ impurity-doped strontium magnesium borate glasses: A comparative evaluation

Two new series of strontium magnesium borate glasses with Dy3+ and Sm3+ activation (both in the concentration range of 0.1–1.0 mol%) were prepared using the standard melt-quenching and characterized. The optical and physical properties of these singly impurity-doped glass series were compared. The optical and physical properties of these glasses were determined in terms of the density, molar volume, optical band gap, absorption and emission intensities, oscillator strength, refractive index and molar polarizability. The XRD analyses confirmed the amorphous nature of the as-quenched samples. The EDX spectra revealed the actual elemental compositions and FESEM images showed the samples homogeneity without cracks. The UV–vis-NIR absorption spectra of the Dy3+- and Sm3+-doped glasses showed nine and ten characteristics bands respectively. The PL spectra of the Dy3+- and Sm3+-doped glasses displayed three ((at 481 nm, blue; 570 nm, yellow; and 661 nm, red) four (559, 596, 643 and 709 nm) significant peaks, respectively. The lasing potentials of the Dy3+- and Sm3+-doped glasses were compared via Judd-Ofelt evaluation. The values of branching ratio and stimulated emission cross-section for the 4F9/2 ? 6H13/2 transition in Dy3+ and 4G5/2 ? 6H7/2 transitions in Sm3+ was maximum, indicating their effectiveness towards photonic devices assembly. The studied glasses have demonstrated high viability for the cutting-edge innovations in the solid?state lighting and high gain optical fibre construction

The role of dysprosium ions on the physical and optical properties of lithium-borosulfophosphate glasses

Achieving outstanding physical and optical properties of borosulfophosphate glasses via controlled doping of rare earth ions is the key issue in the fabrication of new and highly-efficient glass material for diverse optical applications. Thus, the effect of replacing P2O5 by Dy2O3 on the physical and optical properties of Dy3+-doped lithium-borosulfophosphate glasses with chemical composition of 15Li2O-30B2O3-15SO3-(40 - x)P2O5-xDy2O3 (where 0.0 mol.% ≤ x ≪ 1.0 mol.%) has been investigated. The glass samples were synthesized from high-purity raw materials via convectional melt-quenching technique and characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectrometry (EDX), density and UV-vis-NIR absorption measurements. The amorphous nature of the prepared glass samples was confirmed by XRD patterns whereas the EDX spectrum depicts elemental traces of O, C, B, S, P and Dy. The physical parameters such as density, refractive index, molar volume, polaron radius and field strength were found to vary nonlinearly with increasing Dy2O3 concentration. UV-vis-NIR absorption spectra revealed seven absorption bands with most dominant peak at 1269 nm (6H15/2 →6F11/2 +6H9/2). From the optical absorption spectra, the optical bandgap and Urbach's energy have been determined and are related with the structural changes occurring in these glasses with increase in Dy2O3 content. Meanwhile, the bonding parameters (δ) evaluated from the optical absorption spectra were found to be ionic in nature. The superior features exhibited by the current glasses nominate them as potential candidate for nonlinear optical applications

Correlation of mechanical properties and crystal field parameters of europium-doped magnesium-zinc-sulfophosphate glasses

Europium-doped magnesium–zinc–sulfophosphate glasses of molar composition (65 − x) P2O5–20MgO–15ZnSO4–xEu2O3 (x = 0.0, 0.5, 1.0, 1.5 and 2.0) were prepared via melt-quenching method. The synthesized glasses were characterized at room temperature to determine the relationship between Racah and mechanical properties. The FTIR spectra of glasses in the range of 4000–400 cm−1 revealed the presence of characteristic functional groups. The Young’s, shear and bulk moduli of glasses were observed to enhance with the increase in Eu3+ contents. The ratio increased from 0.710 to 0.747 which confirms the increase in the degree of centrality of the glasses. Racah parameters evaluated from first three major absorption bands were reduced from 72.3906 to 60.1111 cm−1 with the increase in Europium contents, thus signifying the weakening in f–f electrons repulsion. Crystal field parameters decrease from 42.2445 to 35.2397 cm−1 denoting strong covalent character of ligand bond of the synthesized glass system. The synthesized glasses have potential for the development of hard surface engineering

Luminescence behavior of Dy3+ ions in calcium sulfo borophosphate glass for white leds

Objectives: To Determine the optical properties of glass by means of ultraviolet, visible and luminescence spectroscopy. Methods/Analysis: Different concentrations of dysprosiumdopedcalcium sulfoborophosphate (CSBP) glasses were produced by the melt quenching method and characterized through absorption, excitation and luminescence spectroscopy and its glassy form was ascertain by XRD. Findings: The emission spectrum of calcium sulfo borophosphate doped Dy3+ glasses displays bands at 482 nm (blue) and 572 nm (yellow) underneath excitation 350 nm, which agree to the transitions of 4F9/2→6H15/2 and 4F9/2→6H13/2 of Dy3+ respectively. The spectrum of the excitation for 572 nm emission takes numerous bands at 321 nm, 347 nm, 386 nm, 422 nm, 449 nm and 470 nm, which is in correspondence with the ultraviolet light emitting diode (320–410 nm) and blue light emitting (450–470 nm). Application: The findings show that calcium sulfo borophosphate doped with Dy3+ glasses could be certainly used as white LEDs

Europium-doped boro-telluro-dolomite glasses for red laser applications: basic insight into spectroscopic traits

Naturally abundant minerals and lanthanide-doped synthetic boro-tellurite networks have become prospective efficient laser hosts because of the synergy between them. Driven by this idea, Eu3+-doped boro-telluro-dolomite (BTD) glasses were prepared via the melt-quenching method. The spectroscopic traits of as-quenched samples were analyzed though experimental and theoretical studies. The result from the derivation of absorption spectral fitting (DASF) model demonstrated the direct allowed transition in the glasses. Moreover, the photoluminescence spectra of the sample containing 1.0 mol% of Eu3+ (BTD1.0Eu glass) revealed a prominent red peak at 611 nm (assigned to 5D0 → 7F2 transition in Eu3+ ion) with a large stimulated emission cross section (7.15×10−22cm2) and a high luminescence branching ratio (61.5%). Furthermore, the attained CIE color coordinates (0.637, 0.363), which lie near the standard red hue (0.67, 0.33), together with high quantum efficiency (92.7%) affirmed the effectiveness of BTD1.0Eu glass as a potential red laser host