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A novel phosphate glass of the P 2 O 5 -SnCl 2 -Fe 2 O 3 system was synthesized using the melt-cooling technique. The effect of substituting SnO for SnCl 2 on the properties of the glass was systematically explored. The material was analyzed using X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), and a thermal expansion test. The thermal expansion coefficient (TEC) analysis revealed that the glass transition temperature initially rises and subsequently falls with increasing SnO content. The incorporation of Sn and Fe ions not only reduces the characteristic temperature of the glass but also enhances its chemical stability, presenting significant potential for applications in low-temperature sealing technologies. [ABSTRACT FROM AUTHOR]

All available thermodynamic properties and phase diagram data of the Sn-O system at 1 atm total pressure were critically evaluated and optimized to obtain a set of thermodynamic functions of all stable phases. The discrepancies among available experimental phase diagram data were resolved. In addition, new experiments were attempted to determine the melting temperature of SnO 2 using sealed Pt capsules. It was confirmed that the melting temperature of SnO 2 is higher than 1700 °C, which was taken into account in the present optimization. The Gibbs energies of the liquid solution of SnO-SnO 2 and all solid compounds were obtained. A new phase diagram at 1 atm total pressure was constructed from the optimized Gibbs energy functions of all phases. [ABSTRACT FROM AUTHOR]

Abstract Cl-doped SnO photocatalysts were synthesized by mechanical alloying (MA) from SnCl 2 and NH 4 HCO 3. The effects of MA time on the structural characterization and photocatalytic activity of SnO powders were studied. Cl-doped SnO nanoparticles can be obtained by MA treatment after 1 h, but MA time considerably affected the crystalline size, microstrain, and photocatalytic properties of the samples. The crystalline size and specific surface area of the SnO samples gradually decreased and their microstrain increased with prolonged MA time. The peak intensity of the photoluminescence spectra of the Cl-doped SnO samples remarkably increased with prolonged MA time. Moreover, the MA samples had good photocatalytic properties. The photodegradation rate of methyl orange dye in 30 min over Cl-doped SnO nanoparticles obtained by MA for 2, 4, and 8 h was approximately 99%. Aging treatment of the SnO samples remarkably affected their phase composition, which can enhance the transformation of SnO to SnO 2. The SnO 2 transformation degree significantly increased with prolonged MA time through aging treatment, which also slightly deteriorated the degradation efficiency of the samples. [ABSTRACT FROM AUTHOR]

Abstract Recently, Tin Monoxide (SnO) has attained a considerable interest due to its striking electronic, optical, thermoelectric and gas sensing properties in various advanced technological applications. In this study, we focus on the first principles calculations to examine the structural, electronic and optical properties of the pristine, 1S, 2S, and 3S doped SnO. The plane-wave ultra-soft pseudopotential method is used under the GGA-PBE exchange-correlation energy with supercell approach. Bandgap reduces with the increase in the concentration of doping from 0.460 eV to 0.330 eV, 0.064 eV for 1S, 2S respectively and shows metallic behavior for 3S doped SnO. Formation and cohesive energies decrease in order of Sn 15 S 1 O 16 < Sn 14 S 2 O 16 < Sn 13 S 3 O 16, which shows that the most suitable and favorable configuration is of Sn 15 S 1 O 16. The static dielectric constant ε 1 (0) and refractive index n (0) are 7.71, 7.82, 8.48, 9.42 eV and 2.76, 2.80, 2.91, 3.07 respectively, which are showing increasing trends. The absorption spectrum and optical conductivity curves of S doping show a significant blueshift towards ultraviolet spectrum. The optical properties and bandgap narrowing effect suggest that the sulfur-doped SnO can be a promising new semiconductor in the field of optoelectronics. [ABSTRACT FROM AUTHOR]

Abstract Atomic layer deposition (ALD) of SnO and SnO 2 thin films was successfully demonstrated over a wide temperature range of 70–300 °C using a divalent Sn-precursor, bis(N- ethoxy-2,2-dimethyl propanamido)tin (Sn(edpa) 2). The regulated growth of the SnO 2 and SnO films was realized by employing O 2 -plasma and H 2 O, respectively. Pure SnO 2 and SnO films were deposited with negligible C and N contents at all the growth temperatures, and the films exhibited polycrystalline and amorphous structures, respectively. The SnO 2 films presented a high transmittance of > 85% in the wavelength range of 400–700 nm and an indirect band gap of 3.6–4.0 eV; meanwhile, the SnO films exhibited a lower transmittance of > 60% and an indirect band gap of 2.9–3.0 eV. The SnO 2 films exhibited n-type semiconducting characteristics with carrier concentrations of 8.5 × 1016–1.2 × 1020 cm−3 and Hall mobilities of 2–26 cm2/V s. By employing an alternate ALD growth of SnO and SnO 2 films, SnO 2 /SnO multilayer structures were successfully fabricated at 120 °C. The in-situ quadrupole mass spectrometry analysis performed during ALD revealed that the oxidation of chemisorbed Sn-precursor occurs dominantly during the Sn(edpa) 2 /O 2 -plasma ALD process, resulting in the production of combustion by-products, whereas the Sn(edpa) 2 /H 2 O ALD process was governed by a ligand exchange reaction with the maintenance of the original oxidation state of Sn2+. [ABSTRACT FROM AUTHOR]

Abstract SnO samples were prepared from SnCl 2 and NH 4 HCO 3 by microwave–hydrothermal method. The effects of temperature on the composition, microstructure, and photocatalytic properties of SnO were studied. Results showed that samples synthesized at 50–90 °C for 10 min were composed of SnO and tiny SnO 2 particles. All SnO samples displayed good photocatalytic activities. The sample synthesized at 60 °C was composed of numerous porous microspheres, which were 5–10 µm in size and assembled by SnO nanosheets. In general, the SnO samples possessed excellent visible photocatalytic properties and can degrade 87.5% of methyl orange within 80 min. [ABSTRACT FROM AUTHOR]

Abstract SnO microspheres were synthesized by a simple one-step ultrasonic reaction method. SnO materials were annealed at 150–250 °C to enhance their photocatalytic performance by adjusting their phase composition and lattice distortion. Effects of annealed temperature on the phase composition, microstructure and photocatalytic performance of SnO materials were investigated in detail. The results reveal that the annealing treatment considerably affected phase composition, absorption in the visible light zone, and the photocatalytic activity of the SnO materials. At increased temperature, SnO 2 content in the products gradually increased. At 250 °C, SnO materials were transformed to SnO 2. Correspondingly, the photocatalytic activity of the samples improved gradually with increasing temperature. The excellent photocatalytic efficiency of 98.3% within 40 min for the SnO microspheres annealed at 225 °C was achieved under the visible-light irradiation. The enhancement of the photocatalytic activity of this sample can be ascribed to lattice distortion of SnO combined with increased SnO 2 content. [ABSTRACT FROM AUTHOR]

We fabricated tin oxide nanowires (NWs) on Au/Si 3 N 4 /Si(001) substrates using thermal chemical vapor deposition (CVD) in a hydrogen reduction atmosphere. Unlike typical thermal CVD conditions, a mixture of H 2 and Ar gas was used as the carrier gas, and a catalyst powder such as graphite was not used. The hydrogen gas maintained the reducing atmosphere and easily vaporized the SnO 2 powder without a catalyst, to supply vapors of Sn and O. This process enables vapor-liquid-solid (VLS) growth of SnO 2 NWs at temperatures below 600 °C. The formation of a eutectic AuSn alloy that acts as a liquid seed during the VLS process contributes to lowering the growth temperature. X-ray diffraction and transmission electron microscopy analysis show that SnO 2 NWs and SnO NWs coexist in the as-prepared sample. The oxygen-deficient atmosphere results in nucleation and growth of SnO NWs. [ABSTRACT FROM AUTHOR]

SnO/Graphitic-C 3 N 4 (g-C 3 N 4 ) photocatalysts were prepared by a simple solid phase grinding-assisted ultrasonic synthesis technology. Results showed that SnO/g-C 3 N 4 composites with moderate g-C 3 N 4 exhibit nanosheet morphology. An intimate interface boundary exists between the g-C 3 N 4 and SnO phases in the composites. The composites possess excellent photocatalytic activity. SnO/g-C 3 N 4 exhibits optimum photocatalytic property (7.66%) and highest photoactivity, which could degrade 98% of methyl orange under visible-light irradiation within 80 min. [ABSTRACT FROM AUTHOR]

High temperature solid state is reported the most common synthesis technique for Ca 2 SnO 4 ceramics, nevertheless it requires high thermal treatment temperature and long synthesis time. Our previous studies indicated that Ca 2 SnO 4 was much easier to form if SnO 2 and CaCO 3 were roasted under CO-CO 2 atmosphere at relatively low temperatures. In this study, the reaction mechanism between SnO 2 and CaCO 3 under 15 vol% CO/(CO+CO 2 ) atmosphere and air atmosphere were firstly investigated by using XRD, SEM, XPS, etc. In addition, the Eu-doped Ca 2 SnO 4 was synthesized by low-temperature solid state reaction under CO-CO 2 atmosphere. The results indicated that the crystal structure and photoluminescence properties of the products were similar to those of samples synthesized under air atmosphere, whereas the synthetic temperature was reduced by more than 300 °C. [ABSTRACT FROM AUTHOR]

We investigated rf-sputtered SnO x thin films after thermal oxidation in ambient air at 245 °C (below the temperature for the disproportionation reaction 2SnO→Sn+SnO 2 ) using an infrared rapid heating furnace. The most significant changes occur during the initial 2.5 min of thermal annealing. The amorphous as-deposited film rapidly crystallized with metallic Sn and SnO phases as identified by XRD after thermal annealing. Both EPMA and XPS indicate decreasing [Sn]/[O] ratios after the initial 2.5 min of annealing, suggesting the occurrence of an oxidation process that is hindered for longer annealing durations. The lower [Sn]/[O] ratio identified by XPS than by EPMA suggests more severe oxidation at the surface. Thermal oxidation improves the transmittance and increases the band gap from 1.80 to 2.79 eV. The annealed films exhibit resistivity of ~16 Ω cm, hall mobility of ~0.6 cm 2 V −1 s −1 , and carrier concentration of ~7×10 17 cm −3 . Both Hall and Seebeck coefficient measurements confirm p-type conductivity for all annealed films. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, single-crystalline SnO2 nanowires have been successfully prepared by a carbothermal reduction process employing SnO as the starting material and CuO as the catalyst. Their morphologies, purity and sizes of the products were characterized by transmission electron microscopy (TEM), selected area electron diffraction, X-ray diffraction, field emission scanning electron microscopy (FESEM) and Raman spectroscopy, respectively. The FESEM images reveal wire-like and rod-shaped nanowires of about 100–800μm in length and 30–200nm in the transverse dimensions. The three observed Raman peaks at 474, 634 and 774cm−1 indicate the typical rutile phase of the SnO2 which is in agreement with the X-ray diffraction results. The influence of some reaction parameters, including the temperature and the reaction duration, on the forming, morphology and particle size of SnO2 crystallize is discussed. [Copyright &y& Elsevier]