Synthesis and Characterization of Sm1-xZrxFe1-yMgyO3 (x, y = 0.5, 0.7, 0.9) as Possible Electrolytes for SOFCs

The novel perovskite oxide series of Sm1-xZrxFe1-yMgyO3 (x,y = 0.5, 0.7, 0.9) were synthesized by solid state reaction method. X-ray diffraction (XRD), Rietveld refinement, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and conductivity analysis were carried out. XRD patterns of sintered materials revealed the shifted Bragg reflection to higher angle for the higher content of Zr and Mg. This is related to the ionic size of the dopant elements. Rietveld refinement showed that all compounds crystallized in cubic space group of Fm-3m. SEM images showed that the grains were well defined with highly dense surfaces makes it potential as an electrolyte material in solid oxide fuel cells (SOFCs) or gases sensors. Impedance spectroscopy at 550-800 °C shows that conductivity is higher at higher temperature. Sm0.5Zr0.5Fe0.5Mg0.5O3 shows the highest conductivity of 5.451 × 10-3 S cm-1 at 800 °C. It was observed that 50% molar ratio of Mg and Zr doping performed highest conductivity.

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Studies on Highly Dense Pure YIG Polycrystalline Ceramics Fabricated by Tape-casting Method

10.21203/rs.3.rs-57431/v1 ◽

2020 ◽

Author(s):

Chong Zhao ◽

Yingkui Li ◽

Xiaofei Shen ◽

Zhijun Cao ◽

Zhiquan Cao ◽

...

Keyword(s):

Tape Casting ◽

Solid State Reaction Method ◽

Grain Structure ◽

Casting Method ◽

Forming Process ◽

Sem Images ◽

Polycrystalline Ceramics ◽

Pure Phase ◽

One Step ◽

Xrd Patterns

Abstract Pure phase Y3Fe5O12 (YIG) ceramics was successfully produced by tape-casting forming process and one-step solid-state reaction method. With the sintering temperature above 1100 ºC, the pure phase YIG ceramics was synthesized with no YIP or Fe2O3 phase in XRD patterns. YIG ceramic sintering at 1400 ºC for 10 h showed a clear grain structure with an obvious grain boundary, and no pores were observed in the SEM images. YIG ceramics in this paper has a high relative density which was 99.8% and the saturation magnetization was 28.2 emu/g at room temperature. The hysteresis loss at temperatures of 230-360 K was smaller than 10 mJ/kg. The tan Se was nearly zero at 6~7 GHz and 11~12 GHz, showing that it can be used as a good material for microwave applications. In addition, the low values of tan and tan indicates that it may have a good electromagnetic wave absorption ability.

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Morphology and Structure of Ni/Zr0.84Sc0.16O1.92 Electrode Material Synthesized via Glycine-Nitrate Combustion Method for Solid Oxide Electrochemical Cell

Applied Sciences ◽

10.3390/app9020264 ◽

2019 ◽

Vol 9 (2) ◽

pp. 264 ◽

Cited By ~ 6

Author(s):

Renz Garcia ◽

Rinlee Cervera

Keyword(s):

Electrode Material ◽

Electrochemical Impedance ◽

Combustion Method ◽

Submicron Particles ◽

Total Conductivity ◽

Sem Images ◽

Conducting Phase ◽

Ion Conducting ◽

Xrd Patterns ◽

Glycine Nitrate Combustion

Nickel oxide and Sc-doped ZrO2 electrode material with a 1:1 wt % composition of NiO and Zr0.84Sc0.16O1.92 was synthesized via a single-step glycine-nitrate combustion method. Different glycine to nitrate (g/n) molar ratios of 0.27, 0.54, and 1.1 were used to investigate its effect on the structural, morphological, and electrical properties of the heat-treated samples. X-ray diffraction (XRD) patterns of the as-sintered samples for all the g/n ratios were indexed to cubic phases of NiO and ScSZ. Upon reduction at 700 °C, NiO was fully reduced to Ni. In-situ XRD patterns showed that the composite Ni/Zr0.84Sc0.16O1.92 electrode material retains its cubic structure at intermediate temperatures from 500 °C to 800 °C. High magnification scanning electron microscopy (SEM) images revealed that nanoparticles of Ni are also formed and situated at the surfaces of ScSZ grains, apart from agglomerated submicron particles of Ni. SEM and electron-dispersive spectroscopy mapping revealed interconnected grains of ScSZ oxide-ion conducting phase. From the calculated conductivity based on electrochemical impedance spectroscopy results, the 0.27 g/n ratio showed an order of magnitude-higher total conductivity among the other prepared samples.

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DC-Bias Dependent Impedance and UV-Vis Diffuse Reflectance Spectroscopy of The Un-Doped and Nb-Doped Ba0.97La0.02TiO3 Ceramics

10.21203/rs.3.rs-228887/v1 ◽

2021 ◽

Author(s):

Marwa Jebli ◽

Nejeh Hamadoui ◽

chaker rayssi ◽

Jemai Dhahri ◽

Mouna Ben Henda ◽

...

Keyword(s):

Electrical Properties ◽

Impedance Spectroscopy ◽

Low Voltage ◽

Electrochemical Impedance ◽

Diffuse Reflectance Spectroscopy ◽

Complex Impedance ◽

Perovskite Oxide ◽

Generation Process ◽

Mobility Of Charge Carriers ◽

Dc Bias

Abstract This report typically discusses the Voltage-Stability (V-S) of the electrical properties of a new perovskite oxide, Ba0.97La0.02Ti1-xNb4x/5O3 (noted BLT, BLT0.9Nb0.08) ceramics which have been meticulously studied. The ceramics typically exhibited a low rise in the real and imaginary parts of the complex impedance on the application of small field levels (up to 5 V). These accurate data, at a low voltage threshold, properly designate a hole-generation process which becomes active. These values considered using AC impedance spectroscopy, nonetheless, were relatively decreased with increasing Nb concentration, as well as increased by this application of a DC bias. For each sample, the complex impedance plot displayed a single impedance semicircle, identified over the high and low frequencies. The equivalent circuit configuration was typically fitted using the Electrochemical Impedance Spectroscopy (EIS) spectra analyzer. Importantly, the electrical properties of our both compounds deduced from the complex electric modulus show a conduction process due to the short-range mobility of charge carriers. An excellent addition of Niobium to some considerable extent can inhibit the grain growth. Conspicuously, the substitution of Nb5+ ions for Ti4+ on B sites leads to the noticeable increase of a band gap. These findings supplied critical insights into the electric mechanisms in BT-based ceramics.

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Synthesis of LiNi0.85Co0.14Al0.01O2 Cathode Material and its Performance in an NCA/Graphite Full-Battery

Energies ◽

10.3390/en12101886 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1886 ◽

Cited By ~ 19

Author(s):

Cornelius Satria Yudha ◽

Soraya Ulfa Muzayanha ◽

Hendri Widiyandari ◽

Ferry Iskandar ◽

Wahyudi Sutopo ◽

...

Keyword(s):

Cathode Material ◽

Solid State Reaction Method ◽

Electrochemical Performances ◽

Sem Images ◽

Voltage Range ◽

Reaction Method ◽

Artificial Graphite ◽

Synthesis Routes ◽

Xrd Patterns ◽

Co Precipitation

Nickel-rich cathode material, NCA (85:14:1), is successfully synthesized using two different, simple and economical batch methods, i.e., hydroxide co-precipitation (NCA-CP) and the hydroxides solid state reaction method (NCA-SS), followed by heat treatments. Based on the FTIR spectra, all precursor samples exhibit two functional groups of hydroxide and carbonate. The XRD patterns of NCA-CP and NCA-SS show a hexagonal layered structure (space group: R_3m), with no impurities detected. Based on the SEM images, the micro-sized particles exhibit a sphere-like shape with aggregates. The electrochemical performances of the samples were tested in a 18650-type full-cell battery using artificial graphite as the counter anode at the voltage range of 2.7–4.25 V. All samples have similar characteristics and electrochemical performances that are comparable to the commercial NCA battery, despite going through different synthesis routes. In conclusion, the overall results are considered good and have the potential to be adapted for commercialization.

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Rietveld refinement, morphology and optical properties of (Ba1−xSrx)MoO4crystals

Journal of Applied Crystallography ◽

10.1107/s0021889813020335 ◽

2013 ◽

Vol 46 (5) ◽

pp. 1434-1446 ◽

Cited By ~ 32

Author(s):

I. C. Nogueira ◽

L. S. Cavalcante ◽

P. F. S. Pereira ◽

M. M. de Jesus ◽

J. M. Rivas Mercury ◽

...

Keyword(s):

Optical Properties ◽

Fourier Transform ◽

Rietveld Refinement ◽

Structural Refinement ◽

X Ray Diffraction ◽

Sem Images ◽

Ft Ir ◽

Xrd Patterns ◽

Co Precipitation ◽

Ft Raman

In this article, the structural refinement, morphology and optical properties of barium strontium molybdate [(Ba1−xSrx)MoO4withx= 0, 0.25, 0.50, 0.75 and 1] crystals, synthesized by the co-precipitation (drop-by-drop) method, are reported. The crystals obtained were structurally characterized by X-ray diffraction (XRD), Rietveld refinement, and Fourier transform–Raman (FT–Raman) and Fourier transform–infrared (FT–IR) spectroscopies. The shapes of the crystals were observed by means of field-emission scanning electron microscopy (FE-SEM). The optical properties were investigated using ultraviolet–visible (UV–Vis) absorption spectroscopy and photoluminescence (PL) measurements. XRD patterns, Rietveld refinement, and FT–Raman and FT–IR spectra showed that all of the crystals are monophasic with a scheelite-type tetragonal structure. The refined lattice parameters and atomic positions were employed to model the [BaO8], [SrO8] and [MoO4] clusters in the tetragonal lattices. The FE-SEM images indicate that increasedxcontent produces a decrease in the crystal size and modifications in the crystal shape. UV–Vis spectra indicated a decrease in the optical band gap with an increase inxin the (Ba1−xSrx)MoO4crystals. Finally, a decrease in the intensity of PL emission is apparent with an increase inxup to 0.75 in the (Ba1−xSrx)MoO4crystal lattice when excited by a wavelength of 350 nm, probably associated with the degree of structural order–disorder.

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Synthesis and Characterization of Flower-Sphere MoS2

Materials Science Forum ◽

10.4028/www.scientific.net/msf.695.429 ◽

2011 ◽

Vol 695 ◽

pp. 429-432 ◽

Cited By ~ 2

Author(s):

Jun Zhou ◽

Xin Zhe Lan ◽

Ping Ren ◽

Qiu Li Zhang ◽

Yong Hui Song ◽

...

Keyword(s):

Particle Size ◽

Hydrothermal Systems ◽

Molar Ratio ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Xrd Patterns ◽

Scanning Electron

The flower-sphere molybdenum disulfide has been synthesized by reaction of Na2MoO4 and CS(NH2)2 with NH2OH·HCl or H2C2O4 as reductant. The microstructure and chemical composition of the product were characterized by means of X-ray diffraction and scanning electron microscope. XRD patterns showed that the molar ratio of Mo to S had a great effect on the purity of the product. When the molar ratio of Mo to S was 1:5, the product was nearly pure MoS2. SEM images showed that the particle size increased as the molar ratio of Mo to S reduced. The MoS2 microspheres had rough surfaces and were constructed with sheet-like structures in the two systems. But the product from the system of NH2OH·HCl as reductant has the bigger particle size, clearer petal-sheets, coarser surface and weaker agglomeration than that from the system H2C2O4 as reductant. The possible chemical reactions in hydrothermal systems were preliminarily discussed.

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Electronic Conductivity of NaCl-KCl Equimolar Melt Containing Eu(III) and Eu(II) Complexes by Electrochemical Impedance Spectroscopy

Zeitschrift für Naturforschung A ◽

10.1515/zna-2006-0906 ◽

2006 ◽

Vol 61 (9) ◽

pp. 486-490 ◽

Cited By ~ 2

Author(s):

Sergey A. Kuznetsov ◽

Marcelle Gaune-Escard

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Ionic Conductivity ◽

Impedance Spectroscopy ◽

Electrode Potential ◽

Electrochemical Impedance ◽

Electronic Conductivity ◽

Molar Ratio ◽

Electrolyte Resistance

The electronic conductivity of molten equimolar NaCl-KCl containing Eu(III) and Eu(II) complexes was studied by electrochemical impedance spectroscopy. The ratio between electronic and electrolyte resistance as a function of the electrode potential was determined. The electronic conductivity was found to be maximal when the amounts of Eu(III) and Eu(II) are about equal. The electronic conductivity of this melt does not exceed 2.3% of the ionic conductivity. Deviation from the molar ratio Eu(III)/Eu(II) = 1 led to a considerable diminution of the electronic conductivity.

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Effect of Neutron Irradiation on Electrical Properties of Bi2Sr2CaCu2 (Bi-2212) Phase Superconductor

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.280.21 ◽

2018 ◽

Vol 280 ◽

pp. 21-25

Author(s):

Nasri A. Hamid ◽

Z.A. Mohiju ◽

Y. Abdullah

Keyword(s):

Electrical Properties ◽

Critical Current ◽

Neutron Irradiation ◽

Flux Pinning ◽

Solid State Reaction Method ◽

Molar Ratio ◽

Conventional Solid State Reaction ◽

Pinning Centers ◽

Xrd Patterns ◽

Phase Superconductor

The effect of neutron irradiation on superconducting properties of Bi2Sr2CaCu2 (Bi-2212) phase superconductor was studied. TRIGA MARK II research reactor with neutron flux of 2.00 × 1011 /cm2s was used as the neutron source. Results between non-irradiated and irradiated samples have been analyzed from the aspects of microstructure and electrical properties. In this work, the bulk samples were prepared using the conventional solid-state reaction method. Molar ratio of Bi2O3, Sr2CO3, CaCO3 and CuO were mixed according to its ratio into composition of Bi:Sr:Ca:Cu = 2:2:1:2. The samples were sintered at 840°C during the sample preparation process. Some of the fully synthesized samples were irradiated with neutron irradiation. Neutron irradiation has been proved to promote better flux pinning properties by introducing larger defects in various superconductor ceramics. Enhanced flux pinning centers in the superconductor is responsible in enhancing the critical current, Ic and critical current density, Jc of the irradiated samples. The samples were characterized through X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The transition temperature, Tc and the Jc were measured by using a cryogenic four-point probe system. The XRD patterns for the non-irradiated and irradiated samples show well-defined peaks of which could be indexed on the basis of the Bi-2212 phase structure. XRD patterns also indicate that irradiation did not affect the Bi-2212 superconducting phase. However, the enhancement of Jc was observed in the neutron irradiated sample and this indicates the effectiveness of .neutron irradiation in creating defects that acted as effective flux pinning centers for vortices.

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Study on Electrical conductivity and Activation Energy of doped Ceria nanostructures

Electrochemical Energy Technology ◽

10.1515/eetech-2017-0004 ◽

2018 ◽

Vol 3 (1) ◽

pp. 49-53 ◽

Cited By ~ 2

Author(s):

N. S. Chitra Priya ◽

K. Sandhya ◽

Deepthi N. Rajendran

Keyword(s):

Activation Energy ◽

Nanocrystalline Materials ◽

Arrhenius Plot ◽

Fluorite Structure ◽

Solid State Reaction Method ◽

Crystalline Solid ◽

Doped Ceria ◽

Sem Images ◽

Nano Crystalline ◽

Xrd Patterns

Abstract Ce0.8Gd0.2O2−δ (GDC) and Ce0.8Sm0.2O2−δ (SDC) nanocrystalline materials are prepared by a solid state reaction method. The synthesized nano crystalline solid solutions have cubic fluorite structure as evident from XRD patterns. The materials are qualitatively analyzed by FTIR. The morphology, size and shape of grains etc. are identified from the SEM images. The grain size of GDC is smaller than that of SDC. The better morphology is obtained for GDC. Hence, this is electrically characterized. The activation energy is calculated from the slope of Arrhenius plot (showing variation of conductivity with temperature).

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