Properties Of Sm Research Articles

Study on the properties of Sm3+-Doped CaTbAl3O7 phosphors

New single phase and adjustable emission phosphors have attracted a lot of attention because of the good luminous properties. In this work, Sm3+ doped CaTbAl3O7 phosphors are prepared in air by solid-state method. The crystal structure, concentration dependent spectra, lifetimes, and luminescence properties are investigated. Because of the 4f8 → 4f75d1 and 4f → 4f transitions of Tb3+ ion, host (CaTbAl3O7) shows an excitation spectrum in the range of 220–520 nm under monitored at 544 nm and emits yellow-green light under excitation 248, 284, and 368 nm due to the 5D4 → 7FJ (J = 0, 1, 2, 3, 4, 5, and 6) transitions of Tb3+ ion. CaTbAl3O7:Sm3+ under monitored 598 nm contains the excitation spectral peaks of both CaTbAl3O7 and Sm3+ ion. With excitation at 368 nm, CaTbAl3O7:Sm3+ glows orange-red light, its PL spectrum has both host (CaTbAl3O7) and Sm3+ ion contributing, and the chromaticity coordinates are about (0.5499, 0.4351). Under excitation 402 nm, the red-orange emission of CaTbAl3O7:Sm3+ is only the contribution of Sm3+ ion and the chromaticity coordinates are about (0.5823, 0.4168). The energy transfer process from Tb3+ in host (CaTbAl3O7) to Sm3+ ions can be confirmed via the spectral properties. We explain the luminous mechanism of CaTbAl3O7:Sm3+ by the energy level diagrams of Tb3+ and Sm3+.

Synthesis and Properties of Sm3+/Gd3+ Co-Doped B2O3–GeO2–Bi2O3 Glass Composition

Synthesis and Properties of Sm3+/Gd3+ Co-Doped B2O3–GeO2–Bi2O3 Glass Composition

Optical and Photoluminescence (PL) Properties of Sm3+ Doped Tellurite Glasses as a Laser Material

Optical and Photoluminescence (PL) Properties of Sm3+ Doped Tellurite Glasses as a Laser Material

Synthesis, spectroscopic and DFT studies of 5-methyl-1H-pyrazole-3-carbohydrazide N-glycoside as potential anti-diabetic and antioxidant agent

A novel pyrazole-carbohydrazide N-glycoside derivative (SM1) was prepared by condensation of D-glucose with 1H-pyrazole-3-carbohydrazide. The structure of SM1 was identified by FT-IR, 1H-NMR, 13C-NMR, UV–Vis and mass spectrometry. Structures and properties of SM1 in gas phase, methanol and aqueous solution were predicted by using hybrid B3LYP method with the 6–31G* and 6–311++G** basis sets. Considerable correlations were observed among the experimental spectra and the corresponding theoretical ones. Both levels of calculations evidence that the glucose moiety modify the dihedral angles and that the C=O and the N-NH group of pyrazole ring are in a cis position. A high negative solvation energy of SM1 in water is observed (-196.36 kJ/mol). Both methods show changes in volumes with the size of basis sets and with the permittivity of solvent while the dipole moments follow approximately a same tendency. NBO and AIM studies predict high stabilities of SM1 with both methods supported probably by low separations MK charges on N7 and O13 atoms while the low reactivity of SM1 could be explained by the low electrophilicity index ω. Complete vibrational assignments of all vibration modes of SM1 are reported together with the scaled harmonic force constants. Compound SM1 was tested in vitro for their α-glucosidase and α-amylase inhibitory activity and the postprandial glucose level after administration of this compound was measured by using oral starch tolerance test (OSTT). The in vitro antioxidant activities of SM1 were determined by DPPH, ABTS, and H2O2 radical scavenging methods and the total reducing power Fe3+-Fe2+ transformation (FRAP). The results shown that SM1 exhibited a potent α-glucosidase inhibition with IC50 value of 59.75 ± 0.80 µM, compared to acarbose (IC50 = 72.58 ± 0.68 µM). The result of OSTT showed that SM1 caused the reduction of blood glucose by 42% at 60 min in diabetic mice, which also showed its significant hypoglycemic effect. Moreover, the results of antioxidant activities showed that the title compound has potent antioxidant and radical scavenger.

Insights into structural and spectroscopic characterization of Sm3+ doped orange rich red emitting CsMgPO4 phosphors

In the present study, Sm3+ activated inorganic orthophosphate CsMgPO4 (CSMP) phosphors were prepared by adopting a solid-state reaction method. The structural phase purity and morphological features were studied by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM), respectively. The molecular structure and vibrational modes were substantiated with the Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy characterization. The optical bandgap of the host and Sm3+ doped phosphors was deduced from the diffused reflectance (DR) spectra with a typical value of 5.72 eV and a small variation is observed with increasing concentrations. A systematic study of photoluminescence (PL) properties of Sm3+ doped CSMP phosphors was carried out. From the room temperature excitation and emission spectra, it is found that the phosphor emits in the orange rich red light under the suitable excitation of 402 nm in the UV region and concentration quenching occurs at x = 0.02 doping level. The emission peaks observed at around 562, 598 and 644 nm confirm the characteristic Sm3+ 4f-4f transitions. The temperature-dependent photoluminescence (TD-PL) of the x = 0.02 (optimum doping) is recorded from 30 to 210 °C, showing good thermal stability even at 150 °C. The thermal quenching mechanisms are discussed based on the configuration coordinate model of excitation and emission. The prepared phosphors are found to exhibit near thermal stability compared to the commercially available red phosphors. PL decay time and quantum efficiency were measured. The colour coordinates are found to lie in the orangish-red region of the colour space. Thus the prepared phosphors CSMP:x Sm3+ can be useful as a red component in designing UV excitable chip-based phosphor-converted white LED applications.

Reinforced Optical Properties of Sm3+ Complexes with β-Hydroxyketone Ligand by Using Methylated Auxiliary Ligands

Solution precipitation method was used to synthesize two avant-grade ternary complexes of Sm3+ ion with 2-hydroxy-4,6-dimethoxy-acetophenone (HDMA) as prime ligand and 5,6-dimethyl-1,10-phenathroline (dmphen) as auxillary ligand. Characterization of these complexes was accomplished by means of elemental analysis, 1H NMR, FT-IR and photoluminescence spectroscopy. Emission spectra recorded at ambient temperature, displayed sharp emission bands at 564, 600 and 646 nm attributed to 4G5/2→6Hj (j = 5/2, 7/2, 9/2) f-f transitions of metal ion. The decent decay time of luminescence and superior colour purity reported in complexes. The correlated colour temperature of these complexes established them as warm light source. The quantum yield was also evaluated for both complexes. HDMA alone could sensitize Sm3+ ion proficiently but the inclusion of auxillary ligands neocuproine (neo) or 5,6-dimethyl-1,10-phenathroline (dmphen) resulted in reinforced optical properties. The results of emission spectra illustrated that these ternary complexes can be one of the most promising substances for fabrication of display devices.

Physical and Structural Properties of Sm3+ Doped Phosphate Glasses

: In this research, the glasses were made with composition (70-x) P2O5 - 10Bi2O3 - 10Na2O - 10Gd2O3 - xSm2O3 (with x = 0; 0.05; 0,1; 0, 5; 1.0; 3.0 mol%). Molar volume, polar radius and inter nuclear distance decreases with increasing concentration Sm3+ in phosphate glass. However the refractive index, susceptibility of the oxide ion, polarizability (α) and reflection loss does not change in value. XRD diffraction shows that the patterns shape of the glasses spectrum are found no sharp peaks along the diffraction angle observation area (2θ). This shows that the concentration of Sm3+ ions does not affect the diffraction pattern of Sm: phosphate glass. The strongest FTIR spectrum is archieved PBNaG: Sm5 galss with wavenumber 871 cm−1.

The Luminescence Properties of Sm3+ or Tb3+ —doped Lu3Ga2Al3O12 Phosphors for X-ray Imaging

Sm3+ or Tb3+ -doped Lu3Ga2Al3O12 phosphors were synthesized by using a solid-state reaction method with Lutetium oxide, gallium oxide and aluminum oxide as host materials, samarium oxide and terbium oxide as doping materials. The mixed powders were sintered at 1500 °C for 5 hours by using a horizontal furnace. In this study, the structures of Sm3+ or Tb3+ -doped Lu3Ga2Al3O12 phosphors were observed using an XRD (X-ray diffraction). The emission spectrum of Sm3+ -doped Lu3Ga2Al3O12 phosphor shows 550–650 nm in wavelength due to 4Gj to 6Hj. The measurement of emission spectrum of Tb3+ -doped Lu3Ga2Al3O12 phosphor was confirmed to 450 to 650 nm wavelength due to 5Dj to 7Fj. These phosphors have a sharp emission spectrum due to their physical properties of f-f transition. The Lu3Ga2Al3O12 has a high effective Z-number (Zeff = 57) which is sensitive to X-ray or γ-ray. Therefore Sm3+ or Tb3+ -doped Lu3Ga2Al3O12 phosphors can be applied for diagnostic X-ray imaging in the medical field.

Microstructures and Properties of Sm2(Zr0.7Ce0.3)2O7/8YSZ Double-Ceramic-Layer Thermal Barrier Coatings Deposited by Atmospheric Plasma Spraying

The properties of Sm2(Zr0.7Ce0.3)2O7 (SZ7C3) as a novel thermal barrier coating (TBC) candidate have been evaluated. There is no evidence for a phase transformation for SZ7C3 from room temperature to 1600 °C. SZ7C3 exhibits a higher sintering resistance than the conventional yttria-stabilized zirconia (YSZ). The Vickers hardness for the SZ7C3 bulk is ca. 9.6 GPa, and the fracture toughness lies in a range of 1.5-2.5 MPa m1/2. Single SZ7C3 coatings and SZ7C3/8YSZ double-ceramic-layer (DCL) coatings were prepared by plasma spraying. The thermal conductivities of SZ7C3 coatings range from 0.4 to 0.6 W m−1 K−1 (significantly lower than those of 8YSZ). SZ7C3 coatings also exhibit moderate thermal expansion coefficients (TECs), near 10.8 × 10−6 K−1 at 1200 °C. The values of thermal expansion coefficients and fracture toughness are higher than those of La2(Zr0.7Ce0.3)2O7 (LZ7C3), which has been proposed as a promising high-temperature (> 1250 °C) TBC candidate material. The thermal cycling lifetime of SZ7C3/8YSZ DCL coating is much longer than that of LZ7C3/8YSZ TBC as demonstrated by the furnace thermal cycling tests, further confirming that SZ7C3 coatings have great potential as high-temperature TBCs for use in the next generation of advanced engines.

A Comparative study of TeO2 concentration on zinc barium boro-tellurite glass doped with Sm3+

Abstract Properties of Sm3+ doped zinc barium boro-tellurite glass (ZBBT glass) with the formula 10TeO2-35B2O3-30BaO-24ZnO-1Sm2O3 and 35TeO2-10B2O3-30BaO-24ZnO-1Sm2O3 prepared by conventional melt quenching technique and their physical, optical and photoluminescence properties were investigated. The physical properties have been measured using a densitometer kit based on Archimedes’ principle. The result of the measurement shows that ZBBT glass with the higher TeO2 concentration have higher value in density and molar volume, but it has the lower value in the lifetime. The UV-VIS-NIR absorption spectra were recorded at room temperature in the wavelength range of 200-2,500 nm. From the measurement, it is known that glass with 10 mol% of TeO2 have a higher absorbance value compared to 35 mol% of TeO2. Seven luminescence bands in excitation spectra represent the transitions from the ground state 6H5/2 to various excited states. Furthermore, the emission spectra were observed under 403 nm light from the xenon flash lamps, four luminescence bands were observed at 562 nm (4G5/2→6H5/2), 598 nm (4G5/2→6H7/2), 645 nm (4G5/2→6H9/2) and 706 nm (4G5/2→6H11/2), intense reddish orange emission was found at 598 nm.

Laser absorption properties of Sm2(C2O4)3∙10H2O prepared by coprecipitation method

Sm2(C2O4)3∙10H2O was prepared by coprecipitation method with Na3Cit as chelating agent. The microstructures were studied using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). The 1060 nm laser absorption properties were characterized by spectrophotometer. The results showed that the composition and morphology of Sm2(C2O4)3∙10H2O could be tuned by varying the molar ratio of Na3Cit to Sm3+ and the aging time. Then, the 1060 nm laser absorption properties were optimized. The spectral reflectivity at 1060 nm was low to 0.831 when the molar ratio of Na3Cit to Sm3+ was 1.2 and the aging time was 24 h. The as-prepared Sm2(C2O4)3∙10H2O can be applied as an effective laser absorber.

High pressure effect on structural and spectroscopic properties of Sm3+-doped alkali silicate glasses

ABSTRACTStructural and spectroscopic properties of Sm3+-doped alkali silicate glasses were investigated after densification at 7.7 GPa in a large volume high pressure apparatus. The glass composition was 33M2O + 66SiO2 + 1Sm2O3, where M = Li, Na or K. Raman and infrared spectroscopy revealed small changes in the vibrational modes dependent on the alkali ion. Irreversible changes were observed in the optical absorption spectra of Sm3+ ions. The Judd–Ofelt parameters were calculated to evaluate the effect of pressure on the local field. For lithium silicate, Ω2 parameter increased, suggesting the densification increased the local asymmetry of the Sm3+ environment. For sodium silicate, this parameter decreased considerably, suggesting the opposite effect on the local field, while for potassium silicate, it remained practically unchanged. The changes induced by high pressure are probably due to the irreversible changes in the distances and bond angles between the rare earth ion and the ligands.

Controlling the Synthesis and Optical Properties of Sm3+-Doped NaREF4 (RE = Y and Gd) and LnF3 (Ln = Y, La, and Gd)

Controlling the Synthesis and Optical Properties of Sm3⁺-Doped NaREF₄ (RE = Y and Gd) and LnF₃ (Ln = Y, La, and Gd)

Magnetic and magnetocaloric properties of the first-order phase transition in Sm0.5+x Sr0.5−x MnO3 compounds

In this work, we present a detailed study on the magnetic and the magnetocaloric properties of Sm0.5+xSr0.5−xMnO3 compounds with x = 0 − 0.1, which were prepared by using a solid-state reaction method. The x-dependent magnetic, as well as magnetocaloric, properties, including the magnetic phase transition, have been studied. The increase in Sm/Sr ratio plays an important role in controlling the Curie temperature (TC). We point out that all the samples undergo a first-order phase transition and exhibit a giant magnetocaloric effect. The magnetic entropy change (ΔSm) of samples was calculated based on isothermal M(H, T) data. The maximum value of ΔSm (denoted as |ΔSmax|) at around TC is found to be 2.6 − 8.9 J·kg −1·K −1 for ΔH = 30 kOe and depends on the value of x. We have also used the universal master curve method for the temperature dependences of ΔSm curves measured at different ΔH values, ΔSm(T,ΔH), to distinguish the magnetic order in the samples. Interestingly, none of the ΔSm(T,ΔH) curves for the samples follow the universal master curve, ΔSm(T,ΔH)/ΔSmax versus θ = (T −TC)/(Tr−TC). As a consequence, a breakdown in the universal behavior of ΔSm(T,ΔH)/ΔSmax versus θ curve is another feature confirming a first-order phase-transition nature.

Spectroscopic and emission properties of Sm3+ doped lead fluoroborate glasses containing alkaline earth metal oxides for efficient visible lasers

Spectroscopic and emission properties of Sm3+ doped lead fluoroborate glasses containing alkaline earth metal oxides for efficient visible lasers

Dielectric properties and relaxation behavior of Sm substituted SrTiO3 ceramics sintered in nitrogen atmosphere

SrTiO3, Sm0.02Sr0.97TiO3, and Sr0.99TiO3 ceramics were prepared by a solid-state reaction method. The structural analysis show that all ceramics are cubic perovskite structure, and the A-site substitution of Sr2+ and Sr vacancies have some impact on the lattice parameters of Sm0.02Sr0.97TiO3, and Sr0.99TiO3 ceramics. Compared with the Sr0.99TiO3 ceramics sintered in N2, of which the dielectric constant was 305 (at 1 kHz and room temperature) and dielectric loss less than 0.007, the dielectric properties of Sm0.02Sr0.97TiO3 ceramics sintered in nitrogen (N2) perform a giant permittivity (>104) as well as a very low tanδ (mostly <0.04) over a broad temperature range from 25 to 200 °C. It could be proved that the Sr vacancies have no contribution to the giant permittivity of the Sm0.02Sr0.97TiO3 ceramics sintered in N2. Based on the relaxation behaviors, X-ray photoelectron spectroscopy (XPS) Spectrum and complex-impedance analysis of ceramics sintered in N2, the giant permittivity and low dielectric loss of the ceramics sintered in N2 were due to the donor doping and the oxygen vacancies.

The Preparation and Physical Characteristic of Sm&lt;sup&gt;3+&lt;/sup&gt; Doped Borotellurite Glass

Borotellurite glasses were generally applied in rare earth optical materials due to their excellent physical properties. Samarium doped borotellurite glasses have been identified as one of the potential candidate for optical applications. Therefore, the aim of this study is to identify the physical properties of Sm3+ doped borotellurite glasses by mean of their density, molar volume, microhardness and X-ray diffraction. In this study, the Sm3+ doped borotellurite glasses of the system (70-x)TeO2-20B2O3-10ZnO-xSm2O3 as the samarium trioxide varies from (x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) have been prepared by melt-quenching method. The amorphous nature of the prepared glass samples have been confirmed through XRD spectral analysis. The values of density are found to vary from 4.541g/cm3 to 4.837g/cm3 as well as the values of molar volume as it varies from 29.118cm3/mol to 28.314cm3/mol with the increase of Sm3+ content. The physical properties corresponding to compositional changes have been analysed and the result are reported and presented.

English

English

Mechanical properties of Sm3+ doped zinc fluoroborate glass

Oxyfluoride glass system based on 30ZnF2-20TeO2-(50 − x)B2O3−xSm2O3, (where x = 0, 0.5, 1.0, 1.5, 2.0, 2.5 mol %) were prepared. The density of each glass was measured and the molar volume was calculated. The model developed by Makishima and Mackenzie (M-M) gave reasonable estimation for different constants of elasticity (Young’s modulus, bulk modulus, shear modulus, Poisson’s ratio). Vickers indentation tests were performed on the series of glass samples. These connections were used to relate the conventional Hardness. Fracture toughness, dissociation energy and packing density were also investigated. The relationship between machinability and brittleness of glass materials were studied. Exposition of the M-M model proved to be good for the constants of elasticity of oxyfluoride glasses.

Optical behaviour of samarium doped potassium yttrium double phosphates

Among a wide variety of solid state materials, alkali lanthanide double phosphates are the subject of extensive spectroscopic investigations for their application as laser active materials. The edge of absorption in this compound is at rather high energies, which makes them suitable as efficient host for luminescent materials.Spectroscopic properties of Sm3+-doped K3Y(PO4)2 are reported basing on the high resolution absorption and emission spectra for various temperatures mainly at 4, 10, and 293K from UV to IR range. The effects of concentration and temperature on intensities and shape of the observed bands were studied. Radiative transition probabilities were calculated from absorption spectra and Judd–Ofelt parameters evaluated. The excited state dynamics will be discussed based on the decay time measurement.