Intrinsic non-stoichiometry and anomalous transport properties of layered oxysulfide LaOPbBiS3

2021 ◽  
Author(s):  
Céline Roux-Byl ◽  
David Berardan
Keyword(s):  
Electron Microscopy ◽  
Low Temperature ◽  
Transport Properties ◽  
Anomalous Transport ◽  
Fluorine Doping ◽  
X Ray Diffraction ◽  
X Ray

We report on the intrinsic non-stoichiometry and the influence of fluorine doping on the low temperature transport properties of layered oxysulfide LaOPbBiS3. From X-ray diffraction coupled to electron microscopy studies,...

Magnesium Nitrate as Additive for Synthesis of Mg(OH)2 Nanoparticles

2012 ◽  
Vol 198-199 ◽  
pp. 99-102
Author(s):  
Qing Gang Kong ◽  
Hai Yan Qian
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Low Temperature ◽  
Magnesium Nitrate ◽  
Crystal Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Size And Morphology ◽  
Scanning Electron

Magnesium nitrate was used as additive for synthesis of Mg(OH)2 (MH) nanoparticles at low temperature (70°C). Mg(OH)2 nanoparticles have platelet-like structure and approximately 40-60nm in thicknesses. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were applied to characterize the crystal phase. The supersaturation degree of solution effects the size and morphology of MH nanoparticles.

SiO2ZrO2 Thin Films as Low Temperature NO2 and O3 Sensors

2015 ◽  
Vol 1088 ◽  
pp. 81-85 ◽  
Author(s):  
T.N. Myasoedova ◽  
Victor V. Petrov ◽  
Nina K. Plugotarenko ◽  
Dmitriy V. Sergeenko ◽  
Galina Yalovega ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Scanning Electron Microscopy ◽  
Low Temperature ◽  
Annealing Temperature ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Operating Temperatures ◽  
Scanning Electron

Thin SiO2ZrO2films were prepared, up to 0.2 μm thick, by means of the sol–gel technology and characterized by a Scanning electron microscopy and X-ray diffraction. It is shown the presence of monoclinic, cubic and tetragonal phases of ZrO2in the SiO2matrix. The crystallites sizes depend on the annealing temperature of the film and amount to 35 and 56 nm for the films annealed at 773 and 973 K, respectively. The films resistance is rather sensitive to the presence of NO2and O3impurity in air at lower operating temperatures in the range of 30-60°C.

MOCVD ZnS:Mn Films: Grain Size Distribution and Crystal Structure as a Function of the Growth Parameters

2001 ◽  
Vol 672 ◽  
Author(s):  
Kathleen A. Dunn ◽  
Katharine Dovidenko ◽  
Anna W. Topol ◽  
Serge R. Oktyabrsky ◽  
Alain E. Kaloyeros
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Grain Size ◽  
Low Temperature ◽  
Film Thickness ◽  
Growth Parameters ◽  
X Ray Diffraction ◽  
Direction Parallel ◽  
X Ray ◽  
Average Grain Size

ABSTRACTZinc sulfide doped with manganese is extensively used for thin film electroluminescent device applications. In order to assess the key material and process challenges, ZnS:Mn layers were fabricated by metalorganic chemical vapor deposition in the 250°-500°C range on an AlTiO/InSnO/glass stack. The microstructure of the ZnS:Mn films was examined by Transmission Electron Microscopy (TEM) as part of a larger study which fully characterizes these films by a variety of structural and chemical characterization techniques, including Rutherford Backscattering, Secondary Ion Mass Spectroscopy, Atomic Force Microscopy, Scanning Electron Microscopy and X-ray Diffraction. For all the growth conditions, the films were found to be polycrystalline having predominantly 2H hexagonal ZnS structure. The ZnS grains are found to grow columnar as the film thickness increases, also widening in the direction parallel to the substrate surface and reaching the 100 - 200 nm average lateral size at the 650 nm film thickness. The presence of the 8H ZnS polytype was detected in the low-temperature ZnS:Mn films by TEM selected area electron diffraction and confirmed by X-ray diffraction analysis. Dark field TEM imaging correlated this 8H ring with very small (∼2.5 nm) grains present throughout the low temperature film with a slightly higher density at the film/substrate interface. The 700°C post-deposition annealing was found to initiate a solid state transformation to the cubic (3C) ZnS crystal structure, and resulted in an average grain size of ∼250 nm at the surface of the annealed film.

Low-temperature instability of Ti2SnC: A combined transmission electron microscopy, differential scanning calorimetry, and x-ray diffraction investigations

2009 ◽  
Vol 24 (1) ◽  
pp. 39-49 ◽  
Author(s):  
J. Zhang ◽  
B. Liu ◽  
J.Y. Wang ◽  
Y.C. Zhou
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Differential Scanning Calorimetry ◽  
Low Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Temperature Instability ◽  
X Ray ◽  
Transmission Electron ◽  
Ceramic Microstructure

Transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and x-ray diffraction (XRD) investigations were conducted on the hot-pressed Ti2SnC bulk ceramic. Microstructure features of bulk Ti2SnC ceramic were characterized by using TEM, and a needle-shaped β-Sn precipitation was observed inside Ti2SnC grains with the orientation relationship: (0001) Ti2SnC // (200) Sn and Ti2SnC // [001] Sn. With the combination of DSC and XRD analyses, the precipitation of metallic Sn was demonstrated to be a thermal stress-induced process during the cooling procedure. The reheating temperature, even as low as 400 °C, could trigger the precipitation of Sn from Ti2SnC, which indicated the low-temperature instability of Ti2SnC. A substoichiometry Ti2SnxC formed after depletion of Sn from ternary Ti2SnC phase. Under electron beam irradiation, metallic Sn was observed diffusing back into Ti2SnxC. Furthermore, a new Ti7SnC6 phase with the lattice constants of a = 0.32 and c = 4.1 nm was identified and added in the Ti-Sn-C ternary system.

LOW TEMPERATURE HYDROTHERMAL SYNTHESIS OF BISMUTH SODIUM TITANATE NANOPOWDERS

2005 ◽  
Vol 04 (04) ◽  
pp. 637-641 ◽  
Author(s):  
PUSIT POOKMANEE ◽  
SUKON PHANICHPHANT
Keyword(s):  
Electron Microscopy ◽  
Low Temperature ◽  
Sodium Titanate ◽  
Bismuth Sodium Titanate ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
X Ray ◽  
Calcination Step ◽  
Bismuth Sodium ◽  
Scanning Electron

Nanopowders bismuth sodium titanate ( Bi 0.5 Na 0.5 TiO 3, BNT ) were synthesized by the hydrothermal route at low temperature in the range of 150-200°C with different holding periods of 5-20 h. Bismuth nitrate, sodium nitrate and titanium (IV) isopropoxide were used as the starting materials. The phase structure was examined using X-ray diffraction (XRD). The morphology of the formed nanopowders was investigated by scanning electron microscopy (SEM). Rhombohedral BNT nanopowders was obtained without calcination step. The spherical nanopowders were agglomerated. The average sizes of particle size were about 50-200 nm.

The Effect of Low-Temperature Glow Discharge Nitriding of Duplex Stainless Steel on Absorption and Desorption of Hydrogen

2011 ◽  
Vol 183 ◽  
pp. 71-80 ◽  
Author(s):  
Bartosz Gołębiowski ◽  
Tadeusz Zakroczymski ◽  
Wiesław Świątnicki
Keyword(s):  
Electron Microscopy ◽  
Stainless Steel ◽  
Low Temperature ◽  
Glow Discharge ◽  
Hydrogen Absorption ◽  
Nitrided Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron ◽  
Absorption Of Hydrogen

The effect of the nitrided layers produced on ferritic-austenitic stainless steel to hydrogen absorption and desorption was studied. The layers were formed during low-temperature glow discharge nitriding process. The microstructure of steel after nitriding and cathodic hydrogen charging was investigated by means of X-ray diffraction and by scanning electron microscopy (SEM). One of the objectives was to determine the quantity of hydrogen absorbed by the steel samples with and without the nitrided layer. To determine the quantity of the diffusible and trapped hydrogen, the electrochemical permeation and desorption methods were used. The influence of the nitrided layer on the entry, absorption and desorption of hydrogen was determined. The results revealed that the nitrided layer hinders absorption of hydrogen into and desorption of hydrogen from the membrane.

Preparation of Size Controllable BaTiO3 Nanoparticles in Microemulsion at Low Temperature

2014 ◽  
Vol 1004-1005 ◽  
pp. 63-68 ◽  
Author(s):  
Zhao Deng ◽  
Ying Dai ◽  
Hua Xiao ◽  
Meng Jun Zhou
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Low Temperature ◽  
Atmospheric Pressure ◽  
Tetrabutyl Titanate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Transmission Electron ◽  
Barium Titanate Nanoparticles

Size controllable Barium titanate nanoparticles were synthesized in microemulsion consisting of water, OP-10, hexanol and cyclohexane under atmospheric pressure and low temperature, with Ba (OH)2·8H2O and tetrabutyl titanate used as starting reactants. Products were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX). The results show that 65°C is the proper temperature for the synthesis. The particle size can be controlled by varying the reactants’ concentration, ω value (molar ratios of water to surfactant) and aging time.

Effects of Plasma Nitriding on Low Temperature Salt-Bath Chromizing of W18Cr4V Steel

2011 ◽  
Vol 213 ◽  
pp. 543-547
Author(s):  
Jin Ling Ye ◽  
Feng Ye
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Low Temperature ◽  
Plasma Nitriding ◽  
Xrd Analysis ◽  
Salt Bath ◽  
Chromium Concentration ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

Effects of plasma nitriding on low temperature salt-bath chromizing of W18Cr4V steel is studied .The chromizing process is investigated by means of optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffraction (XRD). Results show that the specimens are chromized successfully by low temperature salt-bath subjected to plasma nitriding. A chromized layer with average 3.3μm in thickness and 1200HV-1300HV in microhardness is formed on the substrate by chromizing at 610°C for 6h. XRD analysis show that the chromized layer is composed of Cr23C6, CrN, Cr/Fe, (Cr, Fe)7C3 , (Cr, Fe)2N and the surface chromium concentration reaches 77.67%.

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