Samarium Ions Research Articles

Structures and spectroscopic characteristics of barium-sulfur-telluro-borate glasses: Role of Sm3+ and Dy3+ Co-activation

This paper reports the preparation of some samarium ions (Sm3+) and dysprosium ions (Dy3+) co-doped barium-sulfur-telluro-borate glasses using the standard melt quenching. The influence of the co-doping on the structures and spectroscopic traits of these glasses was analyzed to determine the feasibility of achieving an intense lasing and white light-emitting action. The XRD pattern of the as-quenched samples confirmed their glassy nature. The FTIR and Raman spectra showed the existence of BO4, BO3, TeO4, and TeO3 functional groups. The EDX spectra and elemental maps confirmed the presence of right elements and their homogeneous distribution in the glass network. The absorption spectra revealed the characteristics peaks of the Dy3+ and Sm3+. The intense absorption transitions from 6H15/2 to 6P7/2, 4I15/2, 6Fk/2 and 6Hj/2 levels were matched to the Dy3+ and the weak transitions from the 6H5/2 to 6F5/2, 6F3/2, 6H15/2 and 6F1/2 levels were due to the Sm3+. The Judd-Ofelt intensity and radiative parameters were calculated to complement the experimental optical results. The luminescence spectra of the glasses revealed the characteristic emission bands of the co-activated ions which were ascribed to the energy transfer mechanisms from the Dy3+ to Sm3+. Raman and decay curve analyses revealed the low phonon energy (680 cm−1) and a decreasing trend in the lifetimes of the excited states, respectively. The achieved high value of the branching ratio of 85.8% for the 4F9/2 → 6H13/2 transition in BSTSmDy1.5 sample indicated its lasing potency. The CIE plot of the glasses exhibited their prospect for the white light generation.

Structural, Morphological and Magnetic Characterization of Sm-substituted Ni-Zn Ferrite

Background: Rare earth materials are known for its salient electrical insulation properties with high values of electrical resistivity. It is expected that the substitution of rare earth ions into spinel ferrites could significantly alter its magnetic properties. In this work, the effect of the addition of Samarium ions on the structural, morphological and magnetic properties of Ni0.5Zn0.5SmxFe2-xO4 (x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) synthesized using sol-gel auto combustion technique was investigated. Methods: A series of Samarium-substituted Ni-Zn ferrite nanoparticles (Ni0.5Zn0.5SmxFe2-xO4 where x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) were synthesized by sol-gel auto-combustion technique. Structural, morphological and magnetic properties of the samples were examined through X-Ray Diffraction (XRD), Field-Emission Scanning Electron Microscope (FESEM) and Vibrating Sample Magnetometer (VSM) measurements. Results: XRD patterns revealed single-phased samples with spinel cubic structure up to x= 0.04. The average crystallite size of the samples varied in the range of 41.8 – 85.6 nm. The prepared samples exhibited agglomerated particles with larger grain size observed in Sm-substituted Ni-Zn ferrite as compared to the unsubstituted sample. The prepared samples exhibited typical soft magnetic behavior as evidenced by the small coercivity field. The magnetic saturation, Ms values decreased as the Sm3+ concentration increases. Conclusion: The substituted Ni-Zn ferrites form agglomerated particles inching towards more uniform microstructure with each increase in Sm3+ substitution. The saturation magnetization of substituted samples decreases with the increase of samarium ion concentration. The decrease in saturation magnetization can be explained based on weak super exchange interaction between A and B sites. The difference in magnetic properties between the samples despite the slight difference in Sm3+ concentrations suggests that the properties of the NiZnFe2O4 can be ‘tuned’, depending on the present need, through the substitution of Fe3+ with rare earth ions.

Synthesis, characterization and photoluminescence studies of samarium doped zinc sulfide nanophosphors

Nanoparticles of zinc sulfide doped with samarium ions of different molar concentrations from 1 to 5 mol% were synthesized by co-precipitation method. Various metrological tools were used to characterize the as-synthesized nanoparticles for their structural, nanostructural, chemical, optical and photoluminescence characteristics. The results of powder x-ray diffraction pattern and high-resolution transmission electron microscopic images revealed the presence of samarium inside the zinc sulfide nanoparticles, with particle size between 3 and 7 nm. The purity of the ZnS:Sm nanoparticles were obtained from Fourier transform infrared spectral profiles. Large agglomeration of fine particles was shown by the scanning electron microscope images. The UV–Vis diffuse reflectance spectroscopy was used to study the optical absorption properties of the as-prepared ZnS:Sm sample. Photoluminescence studies of samarium doped zinc sulfide nanoparticles showed two major emission peaks when excited at 365 nm, one in the orange region (603 nm) and the other one in the red region (701 nm) due to f-f transitions of the Sm3+ in the 4f5configuration.

Study of trivalent samarium ion embedded lithium-based borate glass for high-density optical memory devices.

Sm3+ ions doped strontium lithium lead borate glasses (SLLB:Sm) were prepared using a conventional melt-quenching technique. The glasses were analyzed using X-ray diffractometry and Fourier transform infrared spectroscopy, optical absorption, fluorescence spectral analysis, and fluorescence lifetime decay. The Judd-Ofelt (J-O) parameters and radiative parameters of the SLLB:Sm10 glass (1.0 mol% Sm3+ ion-doped glass) were calculated using J-O theory. From the emission spectra, among all the synthesized glass, SLLB:Sm10 glass had the highest emission intensity for 4 G5/2 →6 H11/2 transition (610 nm). Emission parameters, such as stimulated emission cross-section and optical gain bandwidth, were calculated. For all concentrations of Sm3+ ions, the decay profile showed an exponential nature and decreased when the Sm3+ ion concentration was increased due to a concentration quenching effect. This result suggests that the synthesized SLLB:Sm10 glass could be used for application in high-density optical memory devices.

Influence of optimized concentration of samarium (III) ions on structural, optical and fluorescence properties of calcium-based lead borate glasses for reddish-orange device applications

The calcium-based lead borate glasses doped with 1 mol% Sm3+ ions were prepared using melt quenching technique. The prepared glass samples were analyzed through an X-ray diffractometer, FT-IR, Optical absorption, Emission, and fluorescence decay analysis. Physical properties have been calculated for the prepared glasses. The absorption spectrum has been recorded for 1.0 mol% Sm3+ ions doped calcium-based lead borate glasses. From the absorption spectrum, oscillatory strengths and JO intensity parameters have been calculated. The visible and near-infrared emission spectra were recorded with 402 nm excitation for 1.0 mol% Sm3+ ions. The prepared glass shows that the highest emission intensity for 4G5/2 → 6H11/2 transition centered at 610 nm. Emission properties for the prepared glass were calculated. Decay profile has been analyzed and lifetime value for 4G5/2 exited level of Sm3+ ion calculated for 1.0 mol% Sm3+ ions doped Ca-based lead borate glass: decay profile was well fitted for exponential decay 2, and the lifetime of 4G5/2 excited level is 1.041 ms. The obtained results suggested that the present 1.0 mol% Sm3+ ions doped calcium-based lead borate glass could be useful for the visible lasers and or photonic display devices applications.

Рассеяние фононов на парамагнитных ионах европия и самария в феррите висмута

The temperature dependence of the thermal diffusivity and thermal conductivity of the multiferroics BiFeO3, Bi0.90Sm0.10FeO3 and Bi0.90Еu0.10FeO3 is studied. It was found that the substitution of bismuth ions by the rare-earth europium and samarium ions in bismuth ferrite leads to a decrease in phonon thermal conductivity in a wide temperature range. It was established that the decrease in the thermal conductivity of bismuth ferrite is due to resonance scattering of phonons at paramagnetic levels of europium and samarium ions.

Formation of samarium(II) in synthetic sborgite prepared in air at low temperature

A mixture of boric acid combined with trivalent samarium doped sodium borate was fired in air at 450 °C. The addition of water to the hot residue resulted in the generation of a product in which the incorporated samarium has been reduced from the trivalent form to the divalent state as identified by emission spectroscopy. This product has been identified as a synthetic form of the mineral sborgite. The divalent samarium emission appears to result from the samarium ion occupying a boron site in the material.

Fabrication of metal-organic based complex film based on three-valent samarium ions-[bis (phosphonomethyl) amino] methylphosphonic acid (ATMP) for effective corrosion inhibition of mild steel in simulated seawater

In the present research, samarium (Sm (III)) nitrate and [bis (phosphonomethyl) amino] methylphosphonic acid (ATMP) were mixed to fabricate a novel corrosion protective film on the mild steel (MS) surface against corrosion in saline solution. EIS results proved that the inhibition performance becomes maximized (98%) for the mixture of 200:600 ppm ATMP: Sm(III) during 120 h MS exposure to the saline media. Potentiodynamic polarization curves ensured that by dominant anodic reaction inhibition the corrosion phenomenon was excellently lowered on the steel substance. SEM and AFM micrographs clarified the deposition of a barrier protective film on the steel surface subjected to the 200:600 ppm ATMP:Sm (III) containing saline solution. Besides, the steel wettability was investigated via contact angle measurements and the outcomes depicted the high hydrophobicity of the metal surface exposed to 3.5% NaCl media containing 200:600 ppm ATMP:Sm (III). EDS, FT-IR and GIXRD analyses results proved the uniform deposition of the protective film comprising of ATMP-Sm3+ and ATMP-Fe2+ complexes as well as samarium oxides/hydroxides on the steel surface.

Investigation of alkali metals (A+ = K, Na, Li) co-doped with samarium ions in the eulytite-type phosphate based phosphors for the enhancement of luminescence properties

Orange-red emitting Ba3Bi2(PO4)4:Sm3+ (here after abbreviated as BaBiPO:Sm) phosphors were synthesized, and their structural, morphological, diffuse reflectance spectra (DRS) and photoluminescence properties were investigated. From the excitation spectrum for the 595 nm emission (4G5/2 → 6H7/2) of the Sm3+ ions, the 403 nm excitation band was found to have maximum intensity. Under the 403 nm excitation, the emission spectrum exhibited bands at 564, 595, 641 and 703 nm. The Rc value was calculated to be ~24.07 Å for the quenching concentration, x = 5% mole of sm3+ ions. The luminescence decay time measurement of samarium doped phosphors was carried out. In addition, the alkali metal ions K+, Na+, and Li+ were co-doped with BaBiPO:5% mole Sm3+ phosphor, and their luminescence properties were discussed. The CIE color coordinates were calculated, and the emission color of the BaBiPO:5% mole Sm3+, and the alkali co-doped phosphors were found to be placed in the orange-red region.

Growth and Study of Scintillation Properties of BaBrI Crystals Activated by Samarium Ions

Growth and Study of Scintillation Properties of BaBrI Crystals Activated by Samarium Ions

Development of ZnO–BaO–B2O3–TeO2 glass doped with Sm3+ for orange emitting material

Zinc barium borotellurite glass samples were synthesized with the chemical composition of 10ZnO–30BaO–30B2O3-(30-x)TeO2-xSm2O3 (where 0.05 ≤ x ≤ 1.50 in mol%). Several techniques for XRD, FTIR, absorption, luminescence and decay time measurements were used to investigate the structural and spectroscopic properties. It was found that the XRD patterns revealed amorphous nature of the glass samples. The structural modification of (TeO4) trigonal bipyramid structural units was observed using FTIR spectroscopy. The UV–VIS–NIR absorption spectra displayed seven absorption peaks corresponding to the energy transitions from the ground level 6H5/2 to 6F11/2 (947 nm), 6F9/2 (1085 nm), 6F7/2(1238 nm), 6F5/2 (1385 nm), 6F3/2 (1492 nm), 6H15/2 (1550 nm), and 6F1/2 (1589 nm) excited levels of Sm3+ ion. For the emission spectra, four peaks revealed the transitions 4G5/2 → 6H5/2 (563 nm), 6H7/2 (601 nm), 6H9/2 (644 nm) and 6H11/2 (705 nm). The phenomenological intensity parameters Ωλ (λ = 2, 4, 6) according to Judd–Ofelt theory were calculated. The J-O parameters have been used to forecast several radiative properties such as transition probability (AR), branching ratio (βR) and stimulated emission-cross-sections (σp) in 4G5/2 excitation level of samarium ion. The decay patterns of the 4G5/2 level were fitted using non exponential as well as Inokuti–Hirayama (IH) model. The luminescence spectra of Sm3+ ion of the glasses was analyzed with The CIE chromaticity color coordinates. According to the CIE coordinates, it was located in the boundary of orange light in the CIE diagram. All of the results indicated that these glass compositions could be used for preparing a material which will be a potential candidate for laser applications.

Switchable Piezoresistive SmS Thin Films on Large Area

Samarium monosulfide (SmS) is a switchable material, showing a pressure-induced semiconductor to metal transition. As such, it can be used in different applications such as piezoresistive sensors and memory devices. In this work, we present how e-beam sublimation of samarium metal in a reactive atmosphere can be used for the deposition of semiconducting SmS thin films on 150 mm diameter silicon wafers. The deposition parameters influencing the composition and properties of the thin films are evaluated, such as the deposition rate of Sm metal, the substrate temperature and the H2S partial pressure. We then present the changes in the optical, structural and electrical properties of this compound after the pressure-induced switching to the metallic state. The back-switching and stability of SmS thin films are studied as a function of temperature and atmosphere via in-situ X-ray diffraction. The thermally induced back switching initiates at 250 °C, while above 500 °C, Sm2O2S is formed. Lastly, we explore the possibility to determine the valence state of the samarium ions by means of X-ray photoelectron spectroscopy.

Study of influence of Sm3+ ions concentration on fluorescence and FT-IR studies of lead barium lithium borate glasses for red color display device applications

The varied trivalent Samarium ions activated lead borate glass with composition 40B2O3+35PbO+15Ba2CO3+(10-x)Li2CO3+ xSm2O3 (where x = 0.0, 0.1, 0.5, 1.0, 1.1, 1.5, 2.0 mol %) have been prepared by adopting melt-quenching method. For investigated glass matrices physical properties like thickness, density and refractive indices, polaron radius etc. were measured/calculated. The investigated glasses are characterized through the X-ray diffractometer (XRD), Fourier Transform Infra-Red (FT-IR), Absorption, Emission and fluorescence lifetime analysis. The radiative properties for the optimized BPbBaLiSm10 glass have been calculated using J-O spectral intensity parameters. The luminescence spectra consist of four bands at 573, 610, 657 and 718 nm, which were assigned to 4G5/2 → 6H5/2, 6H7/2, 6H9/2 and 6H11/2 transitions of trivalent Sm3+ ions respectively. In the present investigated glasses, BPbBaLiSm10 glass has highest emission peak intensity for the transition 4G5/2 → 6H5/2 at 610 nm. The high values of Stimulated emission cross-section (σemi = 7.56 × 10−22 cm2), gain band width parameter (σemi x τexp = 15.25 × 10−28 cm3) and fluorescence lifetime (τexp = 0.951 ms) for 4G5/2 → 6H5/2 transition of BPbBaLiSm10 glass strongly suggesting that the present investigated BPbBaLiSm10 glass may be potential candidate for development of visible lasers and photonics display (red colour) device applications.

Effect of gamma irradiation on some spectroscopic properties of phosphate glass containing samarium ions

Changes of FTIR, UV–Visible spectra, photoluminescence with varying Sm content in phosphate glass containing sodium, lead and aluminum were studied. Refractive index values have been measured and their values were listed to be between ~ 1.5–1.7. Furthermore the effect of subjecting this glass to gamma rays was also investigated. The results showed that glass containing 1%Sm had the highest NBOs according to FTIR, UV-Visble results. The optical energy band gap and Urbach values supported this assumption. The presence of Sm3+ which can be reduced to Sm2+ in addition to the NBOs produced due to the addition of Sm ions in the glass matrix, causing a reduction of gamma rays effect. This may give a clue to the ability of using this glass as an immobilizer or shielded for gamma rays or as a burial for high energy radioactive materials.

Waveguide laser potency of samarium doped BaSO4-TeO2-B2O3 glasses: Evaluation of structural and optical qualities

A series of samarium ions (Sm3+) doped barium-sulfur-telluro-borate glasses of composition (70-x)B2O3-15BaSO4-15TeO2-xSm2O3 (x ranged from 0.0 to 2.5 mol%) was prepared by melt-quenching method and examined via diverse analytical tools. Influence of changing Sm3+ doping contents on the structures and optical attributes of the proposed glasses was determined. The XRD pattern of as-quenched samples verified their glassy states. The FTIR spectra displayed the vibrational modes of tellurites and borates functional groups in the corresponding range of 460–850 cm−1 and 700–1650 cm−1. The EDX elemental maps confirmed the homogeneous distribution of the traced elements in the glass matrix. The UV–Vis–NIR absorption spectra of glasses exhibited nine distinct bands compatible with the transition from lower 6H5/2 state to the excited 6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6F1/2 states of Sm3+. The photoluminescence spectra showed four emission bands allotted to magnetic dipole 4G5/2 → 6H5/2 (moderate green at 562 nm), electric dipole dominated 4G5/2 → 6H7/2 (intense orange at 598 nm), electric dipole 4G5/2 → 6H9/2 (moderate red at 645 nm) and 4G5/2 → 6H11/2 (weak red at 703 nm) transitions in Sm3+, respectively. Glasses containing Sm2O3 contents above 1.0 mol% disclosed luminescence intensity quenching. Evaluated Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6 were discerned to range from 1.48 × 10−20–4.2 × 10−20 cm2, 2.31 × 10−20–4.31 × 10−20 cm2 and 1.26 × 10−20–1.99 × 0−20 cm2 respectively. Furthermore, the lifetime of the samples decreases with increase in Sm3+ contents as unraveled by decay curve analysis. The achieved excellent spectroscopic properties of the proposed glass composition suggested their effectiveness as visible laser for waveguide applications.

Oxy-fluorophosphate glass doped SmO3+ as solid state dosimeter via spectroscopic techniques

In the present work, collective studies on optical, structural and magnetic properties of 0.5% SmO3+ ions in new easily melting fluorophosphate glass of the basic composition 70P2O5–20AlF3–10NaF were carried out. The same combined spectral measurements (UV–Vis, FTIR, and ESR) were repeated after successive gamma irradiation. These collective spectral studies are expected to throw some insight on the effect of host fluorophosphate glass on these selected spectral properties of samarium ions together with identifying the effects of gamma irradiation on both the host fluorophosphate glass and on samarium ions and reaching to the resultant generated induced defects. The experimental results exhibit that, the slope of the UV–Vis line is sufficiently high in order to this tool is preferable to be elected as a suitable tool for the dosimetric purpose for this glass composition. The results in this manuscript propose that it is possible to use these techniques to determine if the glass sample may be used as solid-state dosimeters for gamma dose measurements in the range from 0.1 up to 15 kGy due to their linearity with the absorbed dose, color change, low fading for time periods up to 25 days and good response reproducibility.

The Schottky Effect in Bi0.95Sm0.05FeO3

The temperature dependence of the specific heat of the Bi0.95Sm0.05FeO3 multiferroic has been studied in the temperature range 130–780 K. The substitution of samarium ions for bismuth ions in the bismuth ferrite is found to lead to the appearance of additional specific heat component that is due to the manifestation of the Schottky effect for three-level states and multiplet structure of 4f electrons of samarium ions.

Study intra-4f transitions of Sm3+ ions under direct photoexcitation in TiO2

A systematic study of photoluminescence transitions of samarium ion (Sm3+) incorporated in titanium dioxide (TiO2) powder with anatase structure has been performed. Perceptible changes of luminescence under direct excitation as compared with indirect excitation of Sm3+ in titanium dioxide (TiO2:Sm3+) have been detected. Measurements of photoluminescence excitation spectra for all detected radiative transition of Sm3+ were accomplished. The values of asymmetry ratio were calculated for different excitation wavelengths. The dependence of luminescent intensity on Sm3+ doping concentration in TiO2 host was studied under direct and indirect excitation. Thus, evidences of the existence of the several Sm3+ sites in anatase TiO2 have been presented in this work.

Photodegradation of methylene blue over a new down-shifting luminescence catalyst

TiO\(_{2}\) nanotube arrays prepared by anodization technology are modified with a samarium ion (Sm\(^{3+})\) by a hydrothermal method for use in photodegradation of methylene blue (MB). The samarium ion as a down-shifting luminescence material can improve UV radiation harvesting to increase visible light utilization. The efficiency of the photocatalytic activity for the modified-TiO\(_{2}\) nanotube arrays in degradation of MB was investigated under UV–Vis light irradiation. The results show that Sm–TiO\(_{2}\) nanotubes can increase the photocatalytic efficiency of MB. When TiO\(_{2}\) nanotubes are modified by 0.02 M Sm\(^{3+}\), MB can be almost completely degraded when compared with bare TiO\(_{2}\) nanotubes. This indicates that TiO\(_{2}\) nanotubes structure, surface area and good UV radiation harvesting play important roles in the degradation of MB.

Oxygen-Sensitive Photoluminescence of Rare Earth Ions in TiO2 Thin Films

Some nanocrystalline TiO2 materials are notorious for their photoluminescence (PL), which exhibits a pronounced sensitivity to ambient oxygen and has a potential for optical gas sensing. Here, we utilized pulsed laser deposition to obtain thin (70 nm) anatase TiO2 films containing 1–2 atom % of either samarium (Sm) or neodymium (Nd) impurity ions. The highly porous nanostructure consisted of quite regular, interconnected nanopillars with a wall thickness of 15–20 nm, fully exposing the material to ambient environment. The PL intensity of both ions (induced by 355 nm pulsed laser) responded in a reversible manner to changes of oxygen volume fraction in dry O2/N2 flow. Sm3+:TiO2 worked effectively at room temperature, whereas Nd3+:TiO2 showed an improved relative response at 100–150 °C. Switching between pure nitrogen and oxygen atmospheres affected the PL intensities up to 6 times, with response time of 1 min to O2 and recovery time of 10 min in N2. The PL decay kinetics of Sm3+:TiO2 showed unambiguously t...