High Eu3 Research Articles

Optical temperature-sensitive properties of CaMoO4: Eu3+ phosphors

In this study, CaMoO4: Eu3+ phosphors with molar concentrations of 0.01 %, 0.03 %, and 0.1 % were synthesized via the hydrothermal process. The variable temperature PL spectra demonstrated a pronounced decline in the luminescence of MoO42− with the temperature rising, suggestive of typical thermal quenching behavior, whereas the luminescence of Eu3+ showcased an emerging trend characterized by an initial increase followed by a decline. This phenomenon was attributed to the intensified energy transfer effect from MoO42− to Eu3+ as the temperature increased. The thermal quenching trends between MoO42− and Eu3+ exhibited distinct differences, leading to the acquisition of high relative sensitivity when utilizing the FIR of MoO42− and Eu3+ for temperature sensing. It was found in the experiment that samples with higher Eu3+ doping concentrations exhibited higher Sr. In the CaMoO4: 0.1 % Eu3+ sample, the Sr-max reached 3.19 % K−1 at 303 K, which was an excellent value among inorganic materials. The findings of this paper indicate the potential application of CaMoO4: Eu3+ phosphors for optical thermometry.

Is 3% Eu3+ doping in ZnO unique? An investigative case study of photocatalytic descriptors using multiparameter approach

The study focused on synthesizing Europium (Eu3+) doped ZnO hybrid materials using a hydrothermal method, aiming to create Eu3+: ZnO nanocomposites, which were characterized by powder x-ray diffraction (PXRD), Scanning electron microscopy (SEM), & Tunneling electron microscopy (TEM) techniques. The XRD pattern obtained verifies the successful incorporation of Europium (Eu3+) into Zinc-Oxide (ZnO) host matrix. Scanning electron microscopy (SEM) revealed uniform distribution of ZnO, though agglomeration increased with higher Eu3+ concentrations. The photocatalytic efficiency of these nanocomposites was evaluated by degrading the antibiotic Rifampicin under UV–visible light, where the variant with 3 wt% Eu3+ showed the highest degradation rate (approximately 90% in 90 min). This suggests that the optimal doping concentration for enhanced photocatalytic activity is Eu3+: ZnO −3 wt%. Additional assessments using Electrochemical Impedance Spectroscopy (EIS), Photocurrent Measurements, and UV-visible spectroscopy supported this finding, highlighting the peak efficiency at this specific doping level.

Enhanced Red Emission of Na5Lu9F32: Eu3+ Single Crystal by Introducing of GdF3

AbstractThe bulk Na5Lu9F32 single crystals with high quality serial Eu3+/Gd3+ co‐doped were grown by an ameliorative Bridgman technique. The measurement of X‐ray diffraction (XRD) and analysis of Rietveld refinement were implemented to validate the crystal phase. The Eu3+ doped Na5Lu9F32 single crystal emits intense red emission at 611 nm excited by 394 nm light. The intensity of 1.8 mol % Gd3+ doped sample is boosted by 3.56 times compared with the un‐doped one. The doping of Gd3+ ions replace competitively Lu3+ lattice sites with Eu3+ ions. Thus, they cause the lattice distortion and reduction of symmetry, enabling Eu3+ ions to overcome their 4f forbidden transitions. The change of Eu3+ ion local environment induced by Gd3+ ion doping was explored by the Eu3+ emission spectra and the variations of ratios between red and orange emission intensities (R/O). The fluorescence lifetime indicates that the introduction of GdF3 decreases the probability of non‐radiative transitions and increases the fluorescence lifetime. These results demonstrated that the Na5Lu9F32: Eu3+ single crystal doped with an appropriate concentration of GdF3 is a type of promising red emission single crystal for related optical devices of detector and laser due to its strong red emission, high transparency and high physico‐chemical stability.

Structure and Luminescent Properties of Niobium-Modified ZnO-B2O3:Eu3+ Glass.

The effect of the addition of Nb2O5 (up to 5 mol%) on the structure and luminescent properties of ZnO-B2O3 glass doped with 0.5 mol% (1.32 × 1022) Eu2O3 was investigated by applying infrared (IR), Raman and photoluminescence (PL) spectroscopy. Through differential thermal analysis and density measurements, various physical properties such as molar volume, oxygen packing density and glass transition temperature were determined. IR and Raman spectra revealed that niobium ions enter into the base zinc borate glass structure as NbO4 tetrahedra and NbO6 octahedra. A strong red emission from the 5D0 level of Eu3+ ions was registered under near UV (392 nm) excitation using the 7F0 → 5L6 transition of Eu3+. The integrated fluorescence intensity ratio R (5D0 → 7F2/5D0 → 7F1) was calculated to estimate the degree of asymmetry around the active ion, suggesting a location of Eu3+ in non-centrosymmetric sites. The higher Eu3+ luminescence emission observed in zinc borate glasses containing 1-5 mol% Nb2O5 compared to the Nb2O5-free zinc borate glass evidences that Nb2O5 is an appropriate component for modifying the host glass structure and improving the emission intensity.

Sensitive Luminescence Thermometry through Excitation Intensity Ratio in Eu-Doped BaTiO3.

Optical ratiometric thermometry techniques have gained much attention in recent years due to their reliable and noncontact temperature sensing capability for industrial and biorelated applications. Herein, we exploited the temperature dependence of the absorption band of BaTiO3 (BTO) for novel excitation intensity ratio (EIR) thermometry. Photoluminescence and excitation properties of Eu3+-doped BTO powders were studied as a function of Eu3+ doping concentration. The excitation peak intensities at 397 and 468 nm, corresponding to the 7F0 → 5L6 and 5D2 transitions of Eu3+, were used as EIR parameters. The temperature dependence of the EIR can be explained by the competitive absorption between Eu3+ and the BTO host. The EIR properties were studied in relation to the doping concentration, registering a maximum relative sensitivity (Sr) of 4.89% K-1 in BTO:Eu3+ (0.5%) at 303 K. An amphoteric Eu3+ occupation mode at both Ba2+ and Ti4+ sites was found to interpret the doping concentration dependence of the Sr. The reduced Ba2+ site occupation ratio proved to be responsible for the low Sr values at high Eu3+ doping concentrations. Accordingly, an Eu3+/Ti3+ codoping method was further proposed to improve the Sr by increasing the Ba2+ site occupation ratio. Our result showed that BTO:Eu3+ (0.5%) demonstrated an enhancement of Sr from 4.89 to 6.42% K-1 at 303 K after 2% Ti3+ codoping.

Interrupting the long-range energy migration among Eu3+ by the introduction of unequivalent [NaO8] units to achieve both high quenching concentration and quantum yield in NaY2Ga2InGe2O12

In the pursuit of optimizing white light-emitting diodes (WLEDs), Eu3+-doped phosphors have emerged as a key component in strategies that combine ultraviolet (UV) LED chips with red, green, and blue (RGB) tricolor phosphors. However, their application has been notably constrained by concentration quenching and thermal quenching. To address this challenge, we have developed a series of novel red phosphors, NaY2-xGa2InGe2O12:xEu3+. The powder X-ray diffraction (XRD) indicates that the NaY2Ga2InGe2O12(NYGIG) belongs to the garnet family. The [NaO8] unit replaces one-third of the eight-coordinated sites of garnet and leaves the other two-thirds for the [YO8], which helps to prevent long-range energy migration among Eu3+ especially when the eight-coordinated sites were highly substituted. Such a structure feature allowed the NaY2-xGa2InGe2O12:xEu3+ phosphor to achieve an optimal quantum yield of 95.6% at an extremely high Eu3+ doping x value up to 1.2. Moreover, further studies on the temperature-dependent luminescence spectra confirm that an anomalous thermal quenching phenomenon will occur when the NaY2-xGa2InGe2O12:1.2Eu3+ phosphor is properly excited. In application, the combination of the red-emitting NaY2-xGa2InGe2O12:1.2Eu3+, blue-emitting BaMgAl10O17:Eu2+, and green-emitting Zn2SiO4:Mn2+ phosphors can realize high color rendering (CRI∼93) white light with the with CIE coordinates of (0.353,0.350), indicating that the NYGIG:Eu3+ phosphor own a promising potential for WLEDs.

High concentration Eu3+ doped yttria-stabilized zirconia ceramics

The series of yttria-stabilized zirconia (YSZ) ceramics doped with high Eu3+ ions concentration (up to 15 wt%) were successfully fabricated by Spark Plasma Sintering (SPS) technique for the first time. The effect of europium concentration and atmospheric annealing on the optical, structural, and luminescent properties has been studied in detail. The combination of XRD and EDS data allows to find two phases in tested YSZ:Eu ceramics such as ZrO2 and Zr2O. The highest transmission values were achieved about 63% at 600 nm for the 10 wt% of Eu2O3 doped YSZ ceramics without annealing. When the annealing temperature changes from 1300° to 1600°C the transmission values increase to 70%. An analysis of the photoexcitation and photoluminescence spectra showed that the main excitation bands are determined by the direct excitation of the 7F0 ground state to higher 4 f levels with following radiation transitions in Eu3+ ions. The optimal Eu3+- dopant concentration in YSZ ceramics was established and the process of emission quenching was discussed. The luminescence decay kinetics are approximated by the single or sum of two exponential functions in dependence of Eu3+ ions concentrations.

Luminescence properties and energy-transfer behavior of Y2-x-yBixEuyMgTiO6 phosphors

In recent years, double perovskite has become a research hotspot of luminescent matrix materials due to its flexible structure, easy doping and good thermal stability. By using a high temperature solid-state technique, Bi3+ and Eu3+ co-doped Y2-x-yBixEuyMgTiO6 (0 ≤ x ≤ 0.1, 0 ≤ y ≤ 0.5) phosphors were made. X-ray diffraction (XRD) analysis shows that the crystal structure of all samples is monoclinic system, P21/n; Bi3+ and Eu3+ can be doped into the position of Y3+ in the substitution system of Y2MgTiO6. Both photoluminescence spectroscopy (PL) and X-ray excitation luminescence spectroscopy (XEL) were used to investigate the link between Bi3+ and Eu3+ doping concentrations and luminescence intensity. PL shows that: When 375 nm is used as the excitation wavelength, by varying the doping concentration of Eu3+ in the Y1.995-yBi0.005EuyMgTiO6 phosphor, it is possible to create the color-tunable emission from blue to red; The introduction of an appropriate amount of Bi3+ will increase the typical Eu3+ emission; The way that the system's Bi3+ and Eu3+ exchange energy can be observed by combining the fluorescence decay curve and photoluminescence. Fitting by concentration quenching model shows that the resonant dipole-dipole transition is the mechanism of energy transfer between Bi3+→Eu3+; X-rays may successfully stimulate the phosphor, and the spectral distribution of XEL and PL is basically the same; The introduction of an appropriate amount of Bi3+ is also beneficial to improving the sensitivity of XEL; Changes in temperature affect the sample's emission intensity; In addition, the samples remain stable for an extended period while being continuously exposed to X-rays at various environmental temperatures. The a forementioned findings suggest that the phosphor has potential use value in the lighting industry, X-ray imaging and temperature sensor.

Synthesis and Photoluminescence characterization of Sr3La(AlO)3(BO3)4:Eu3+,Sm3+ Phosphor for W-LED

A Red emitting with high efficiency Eu3+ doped Sr3La(AlO)3(BO3)4 and Sm3+ doped Sr3La(AlO)3(BO3)4 phosphors has been synthesized by combustion method, meanwhile, the photoluminescence properties of samples are investigated in detail. Morphology by SEM and chromaticity by CIE was studied. The results show that the excitation extends from 340 nm to 420 nm, with the highest excitation (394 nm and 406 nm) being in the violet area for Eu3+ and Sm3+ doping, indicating that the phosphor can correlate well with LED chips. Under violet light excitation of 394nm the phosphor Eu3+ doped Sr3La(AlO)3(BO3)4 and of 406 nm the phosphor Sm3+ doped Sr3La(AlO)3(BO3)4 can emit strong red light showing main emission peaks located at 617 nm and 602 nm are observed respectively. The PL properties implies the excellent stability of the phosphor. These results imply that the importance red phosphors Sr3La(AlO)3(BO3)4:Eu3+ and Sr3La(AlO)3(BO3)4:Sm3+ in W-LEDs under NUV excitation.

High selectivity and fluorescence reversible Eu3+ sensor based on GSH-capped AgZnInS QDs.

Fluorescence sensors for trivalent europium ions (Eu3+) are seldom reported. We study the synthesis of water-soluble quaternary quantum dots (QDs) and investigate their fluorescence sensor application for detecting Eu3+ The as-synthesized glutathione (GSH)-capped AgZnInS (AZIS) QDs show great sensitivity and selectivity to Eu3+among 12 different metal cations. Detailed experimental results indicate that the fluorescence response of the AZIS QDs to increasing concentration of Eu3+ ([Eu3+]) include intensity quenching and peak wavelength blueshift. With the addition of OH-, the fluorescence response reverses. Electron transfer is considered to be the mechanism for the fluorescence quenching and peak wavelength blueshift of the GSH-capped AZIS QDs. Our work provides a new, to the best of our knowledge, method for the detection of Eu3+.

Microstructure and Photoluminescence of ZrTiO4:Eu3+ Phosphors: Host-Sensitized Energy Transfer and Optical Thermometry

Orthorhombic ZrTiO4 is an attractive dielectric material; its optical properties are, however, less known. In this paper, we reported on the microstructure and luminescence studies of pristine ZrTiO4 and Eu3+-doped ZrTiO4 phosphors. The results indicated that two types of TiO6 octahedra, the isolated/ localized and coupled/delocalized, coexisted in host matrix. Eu3+ doping could induce oxygen vacancy defect states located below the bottom of the conduction band. Pristine ZrTiO4 showed bright yellow luminescence via STEs recombination at defects sites at low temperatures, but significant thermal quenching occurred due to STEs migration to quenching centers at elevated temperatures. Effective host sensitized energy transfer to Eu3+ was observed in ZrTiO4:Eu3+ phosphors and yielded the red characteristic emissions of Eu3+. Anomalous STEs luminescence enhancement and spectral blue-shift in the excitation spectra with higher Eu3 + concentration appeared and were explained by considering three factors: competitive absorption between electron transitions from the top of the valence band to the defect states and host conduction band, Eu3+ doping driving the production of more isolated TiO6 octahedra, and energy back-transfer from Eu3+ activators to other titanate groups. On the basis of the dual-emitting combination strategy involving host STEs and Eu3+ luminescence, ZrTiO4:Eu3+ phosphors were demonstrated to be ratiometric self-referencing optical thermometric materials, with a working range of 153–313 K and a maxima of relative sensitivity to ~1.1% K−1 at 243 K.

Highly red luminescent stabilized tetragonal rare earth-doped HfO2 crystalline ceramics prepared by sol-gel

We report high incorporation of rare earth ions (RE3+) into hafnia nanoparticles prepared by the sol–gel method and investigate how these dopants affect hafnia structure and phase transformation. An ethanolic suspension containing 5-nm hafnia nanoparticles was obtained from HfOCl2.8H2O in ethanol. Pure and 0.1–7 mol% Eu3+-doped materials afforded HfO2 monoclinic phase, whereas hafnia nanoparticles added with 10 and 20 mol% Eu3+ were stabilized in the tetragonal phase. Structural evolution of the nanoparticles was analyzed by Eu3+ luminescence spectroscopy and excited level lifetimes. The emission spectra in the visible region showed an increase of the Eu3+ site symmetry due to hafnia phase transformation from monoclinic to tetragonal upon increasing Eu3+ concentration. Concentration quenching, followed by lifetime measurements, occurred at high Eu3+ concentration (20 mol %). The hafnia tetragonal phase was stabilized with non-optically active La3+ (a fixed concentration of 10 mol %), co-doped with a lower concentration of Eu3+ ions (from 0.1 to 3 mol %). This strategy ensured that Eu3+ luminescence in tetragonal hafnia was intense and prevented quenching by the high Eu3+ concentration. In this sense, the hafnia structure and emission properties can be tailored by the RE3+ concentration, so that an interesting material for applications in photonics and biophotonics can be achieved.

Synthesis and photoluminescence performance of single-component Ca3YAl3B4O15:Dy3+, Eu3+ white-emitting phosphor for white light-emitting diodes

A single-component Ca3YAl3B4O15 (CYAB):Dy3+, Eu3+ phosphor was synthesized by the traditional high temperature solid-phase method, Dy3+ and Eu3+ were codoped in the structure to obtain a warm white emission. The results of XRD and EDS revealed that all samples had the standard Ca3YAl3B4O15 structure, and no impurity phase appeared with codoping. The emission of Dy3+ in CYAB consisted of both main peaks at 476 nm and 570 nm, with which a white emission could be observed. Furthermore, a characteristic emission peak of Eu3+ appeared at 617 nm in Dy3+/Eu3+-codoped samples to supplement red component for the white emission of Dy3+, due to the energy transfer effect between Dy3+ and Eu3+. With the amount of Eu3+ raised, the correlated colour temperature of CYAB:Dy3+, Eu3+ phosphor obviously decreased, and a warm white light was successfully realized from the manufactured w-LEDs. Therefore, all results indicated that the single-component Dy3+/Eu3+ codoped CYAB white-emitting phosphor had a potential application in ultraviolet excited w-LEDs.

Optical properties of Sr3Gd(PO4)3: Eu3+ phosphors for white LED sources

The SGPEux phosphors of composition Sr3Gd(1–x)(PO4)3:xEu3+ were synthesized by modified citrate-gel combustion method for white LED sources. The optimum conditions of synthesis were obtained from thermogravimetric and differential scanning calorimetry. The synthesized phosphors were crystallized into BCC structure with JCPDS No. 29–1301. The presence of various bonds due to stretching and bending vibrations of different functional groups were studied through Fourier transform infrared spectroscopy. The morphology was examined using high-resolution scanning electron microscopy. The luminescence analysis was carried out through photoluminescence excitation and emission studies. The charge transfer band and f-f transitions of Gd3+ and Eu3+ ions cause a transfer of energy from Gd3+ to Eu3+. A suitable excitation wavelength for efficient luminescence was selected as 273 nm by studying the emission properties at different excitations. The quenching in luminescence noticed beyond 2.0 mol% was assigned to non-radiative transitions at higher Eu3+ concentrations. The analysis of colour perception and colour temperature of emitted luminescence was studied using chromaticity coordinates evaluated from the emission spectra. The observed results suggest that the 2.0 mol% of Eu3+ doped SGPEu phosphor has more proficiency to design new class of w-LED sources.

Enhanced luminescence performance in double perovskite Na4/5Gd16/15-xMgWO6: xEu3+ red-emitting phosphors for white LEDs through cation modification

Red-emitting phosphors with efficient emission and outstanding thermal stability play a vital role in enhancing the luminescence performance and lighting quality of the phosphor-converted white light-emitting diodes. However, eliminating the concentration quenching and thermal quenching of the red-emitting phosphors is still a significant challenge for the development of efficient light source. Here, a series of red-emitting Na4/5Gd16/15-xMgWO6: xEu3+ phosphors with enhanced luminescence performance were designed and prepared by sol-gel method. Crystal structure, luminescence properties, and decay results were investigated and discussed in detail. It is found that these red-emitting phosphors are monoclinic crystals with C2/m space group. Under near-ultraviolet and blue light excitation, Na4/5Gd16/15-xMgWO6: xEu3+ phosphors exhibit sharp red emission of Eu3+. A delayed concentration quenching of luminescence is demonstrated at a high Eu3+-doping concentration of x = 0.6, which result in alleviated nonradiative relaxation and thus increased decay time of Eu3+. Besides, the phosphor can achieve a superior thermal stability and maintain the luminescence intensity of 82.5% even up to 150 °C by changing the local environment based on cation vacancy engineering and cation disorder effect. The Na4/5Gd16/15-xMgWO6: xEu3+ phosphors are demonstrated to have great application prospects in the solid state lighting.

Polymorph controlled synthesis and photoluminescence properties of Eu3+ doped BiNbO4

Homogeneous doping of rare earth (RE) ions at atomic level is ideal for enhancing luminescence efficiency. Molten-salt synthesis facilitates crystal growth with improved phase-selectivity and dopant homogeneity. Herein, we present a facile and phase-selective synthesis of orthorhombic α-BiNbO4 and monoclinic β-BiNbO4 under Na2SO4-K2SO4 fluxes in the temperature range of 900 °C to 1050 °C. A series of Eu3+ doped BiNbO4 samples with different crystalline structures were obtained. The influences of Eu3+ doping on the crystal structure were systematicly investigated. α-BiNbO4 has a higher Eu3+-doping limit (>15 mol%) while β-BiNbO4 was unstable upon Eu3+ doping and gradually transformed into α-BiNbO4 with the increase of Eu3+ doping concentration. Moreover, all prepared Eu3+ doped BiNbO4 samples can be effectively excited by near-ultraviolet and blue light and exhibit intense red emissions due to the 5D0/7F2 transition of Eu3+ ions. In addition, the quenching concentration can reach above 10 mol% Eu3+ for both polymorphs. The temperature-dependent emission results revealed that α-BiNbO4 possesses a superior thermal stability with activation energy of 0.271 eV, larger than β-BiNbO4 with activation energy of 0.233 eV. The results reported here provide new insights into the understanding of polymorph-dependent property for photon down-conversion rare-earth luminescence of BiNbO4:Eu3+.

Color tunability imparted by multi-peak emissions of Eu3+ in fluoride-phosphate phosphors

Miscible-order NaGdF4 fluoride-phosphate phosphor has been synthesized based on tin-fluorophosphate glass with low-melting-point, retaining excellent luminescence property of fluoride nanoparticles. Multi-peak emissions from metastable 5DJ (J = 0, 1, 2 and 3) levels are released effectively in the Eu3+ doped fluoride nanoparticles, which lifetimes are at the order of millisecond and quantum efficiency at 5D0 level in high Eu3+ concentration still remains 88.9%. On the basis of multi-peak emissions from Eu3+ and wide-band blue framework from Sn2+, the color coordinates of the fluoride-phosphate phosphors are regulated to the white light region and the color rendering index reaches up to 88. Tunable color and high color rendering index make fluoride-phosphate phosphor become a potential candidate for high-quality white light source.

Systematic Analysis of the Crystal Chemistry and Eu3+ Spectroscopy along the Series of Double Perovskites Ca2LnSbO6 (Ln = La, Eu, Gd, Lu, and Y).

Eu3+ (1 mol %)-doped Ca2LnSbO6 (replacing Ln3+; Ln = Lu, Y, Gd, and La) and Ca2EuSbO6 were synthesized and structurally characterized by means of X-ray powder diffraction. The Eu3+ luminescence spectroscopy of the doped samples and of Ca2EuSbO6 has been carefully investigated upon collection of the excitation/emission spectra and luminescence decay curves of the main excited states. Surprisingly, apart from the dominant red emission from 5D0, all the doped samples show an uncommon blue and green emission contribution from 5DJ (J = 1, 2, and 3). This is made possible thanks to both multiphonon and cross-relaxation mechanism inefficiencies. However, the emission from 5D3 is more efficient and the decay kinetics of the 5DJ (J = 0, 1, and 2) levels is slower in the case of Y- and Lu-based doped samples. This evidence can find a possible explanation in the crystal chemistry of this family of double perovskites: our structural investigation suggests an uneven distribution of the Eu3+ dopant ions in Ca2YSbO6 and Ca2LuSbO6 hosts of the general A2BB′O6 formula. The luminescent center is mainly located in the A crystal site, and on average, the Eu–Eu distances are longer than in the case of the Gd- and La-based matrix. These longer distances can further reduce the efficiency of the cross-relaxation mechanism and, consequently, the radiative transitions are more efficient. The slower depopulation of Eu3+ 5D2 and 5D1 levels in Ca2YSbO6 and Ca2LuSbO6 hosts is reflected in the longer rise observed in the 5D1 and 5D0 decay curves, respectively. Finally, in Ca2EuSbO6, the high Eu3+ concentration gives rise to an efficient cross-relaxation within the subset of the lanthanide ions so that no emission from 5DJ (J = 1, 2, and 3) is possible and the 5D0 decay kinetics is faster than for the doped samples.

Synthesis of high luminescent Eu3+ doped nanoparticle and its application as highly sensitive and selective detection of Fe3+ in real water and human blood serum

The present work reports a highly efficient Ca doped Eu: Y2O3 i.e Ca0.05Eu0.01Y1.94O3 (CEY.) nanophosphor material synthesized through a facile combustion method, as a simple and selective turn-off fluorescence probe for the quantitative analysis of iron ions (Fe3+). The proposed sensor allows the quantification of iron in the range of 10 µM–90 µM with a limit of detection (LOD) ∼ 63.2 nM under the natural pH range. Moreover, CEY nanophosphor shows an excellent fluorescence phenomenon with a gradual increase in the Fe3+ ion concentration. It has been observed that the corresponding PL intensity gets completely quenched with 500 µM Fe3+ ion concentration. Furthermore, the applicability of the sensor as an efficient probe has been investigated with real water samples, iron tablets, and human blood serum (HBS). The selectivity of the probe has also been analyzed with various metal ions and biomolecules. Thus, in turn, the as-obtained sensing probe illustrates an excellent accuracy, sensitivity, and selectivity, and offers potential application in clinical diagnosis, biological and real water sample studies, with the detection of Fe3+ ion. Furthermore, it does not require any acidic medium for a level-free, and non-enzymic detection of a real sample with almost not affecting the sample quality and henceforth provides more reliable results.

Nonlinear optical, optical limiting and radiation shielding features of Eu3+ activated borate glasses

Effect of trivalent europium ions on optical nonlinear and limitng features of antimony sodium borate gasses was studied at 532 nm using Z-scan method with pumping under nanosecond laser pulses. The Z–scan profile of studied glasses in open aperture configuration showed two photon absorption which is because of reverse saturable absorption. As the Eu2O3 concentration is elevated in the composition, the two–photon absorption coefficients were increased while the opposite trend has been noticed in optical limiting threshold values. This endorse, the high Eu3+ doped antimony sodium borate glasses are potential materials for fabricating the optical limiters to work in visible region for the safeguard of delicated instruments and also human eyes from high energy laser radaitions persuaded damages. Further, the linear attenuation coefficient (LAC) revealed the incorporation of Eu2O3 enhances the LAC and thus an improvement on the shielding competence of the fabricated glasses occurs with the addition of Eu2O3. The effective atomic number (Zeff) results showed that the maximum interactions between the photons and the atoms of the glasses occurs at 0.122 MeV and the glass samples have a good blocking ability to the photons. The half value layer (HVL) found that to reduces as the Eu3+ content elevated to higher level in the composition. The radiation shielding factors showed that SNBEu2 glass with the 2 mol % of Eu2O3 is the superior shield out of the fabricated SNBEux samples.