Preparation and Electrical Properties of Ternary Compound (PbTe)1-x(SnTe)x with Nanocrystallines

2007 ◽  
Vol 280-283 ◽  
pp. 389-392
Author(s):  
J.L. Cui
Keyword(s):  
Reaction Time ◽  
Electrical Properties ◽  
Solvothermal Method ◽  
Similar Material ◽  
Vacuum Melting ◽  
Ternary Compounds ◽  
Grain Sizes ◽  
Pure Compounds ◽  
Maximum Power Factor ◽  
Synthesized Materials

Ternary compounds (PbTe)1-x(SnTe)x with nanocrystallines were synthesized at a temperature of 180oC by conventional solvothermal method. XRD analyses revealed that relatively pure compounds can be synthesized using ethylenediamine as a solvent only when a reaction time of at least 24h is applied. The XRD results are in agreement well with those from EMPA analysis. The grain sizes of the materials, ranging from 50~70nm, are slowly increased with reaction time. Measurements showed that the maximum power factor of about 6.0×10-4 W.m.K-2 for the synthesized materials are higher than that of similar material prepared by vacuum melting.

Effect of Ag addition in Sn on growth of SnTe compound during reaction between molten solder and tellurium

2010 ◽  
Vol 25 (2) ◽  
pp. 391-395 ◽  
Author(s):  
Chien-Neng Liao ◽  
Yen-Chun Huang
Keyword(s):  
Particle Size ◽  
Reaction Time ◽  
Electrical Properties ◽  
Bismuth Telluride ◽  
Molten Solder ◽  
Thermoelectric Modules ◽  
Ag Addition ◽  
Mean Particle Size ◽  
Mechanical And Electrical Properties ◽  
The Mean

SnTe is the most common compound formed at the bismuth telluride/metal soldered junction of thermoelectric modules. It affects the mechanical and electrical properties of the soldered junction. In the study we investigate the growth of SnTe compound during reaction between molten Sn–3.5Ag solder and tellurium at 250 °C. We found that the growth of SnTe is suppressed by Ag–Te bilayer compounds that block further reaction between liquid Sn and Te. With increasing reaction time, the SnTe morphology becomes rough as a result of coarsening of SnTe grains. The growth of SnTe grains follows the conservative ripening kinetics with the mean particle size proportional to one-third power of reaction time.

scholarly journals Effect of reaction parameters on WOx nanostructures by the solvothermal process

2021 ◽  
Vol 4 (3) ◽  
pp. 234-244
Author(s):  
Amelia Olivas Sarabia ◽  
Marlene N Cardoza-Contreras ◽  
Gonzalo Lastra Medina ◽  
Marcos Alan Cota Leal ◽  
Selene Sepúlveda Guzmán
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Photoelectron Spectroscopy ◽  
Solvothermal Method ◽  
Ultra Violet ◽  
Oxidation States ◽  
X Ray Diffraction ◽  
Reaction Parameters ◽  
X Ray ◽  
Xrd Patterns

In this work, nanowires and nanorods of WOx have been synthesized by the solvothermal method. The effect of reaction time and acetic acid as solvent were studied. X-ray diffraction (XRD) patterns showed the monoclinic WO2.72, WO2.79, and orthorhombic WO3 crystalline structures. Scanning Electron Microscopy (SEM) and High-Resolution Transmission Electronic Microscopy (HRTEM) images presented nanostructures such as nanowires and nanorods at different sizes. Band gap energies were supplied by Ultra Violet visible (UV-vis) absorption spectra. The Photoluminescence (PL) spectra exhibited three emission peaks in the blue zone at 440, 460, and 484 nm. X-ray Photoelectron Spectroscopy (XPS) was used to calculate W6+, W5+, and W4+ oxidation states. The results showed that increasing the reaction time from 10 h to 24 h affected the crystalline structure from monoclinic to orthorhombic. Moreover, with the addition of acetic acid as solvent, the crystal structure is not affected but stabilizes the monoclinic phase in the course of time.

Effect of Sulfur Precursors on Crystallographic, Optical, and Electrical Properties of Cu2SnS3 Nanoparticles

2021 ◽  
Author(s):  
Mohamed Samir Abdel-Latif ◽  
Abdallah Rezk ◽  
Ahmed Abdel-Moniem ◽  
Amr Hessein
Keyword(s):  
Electrical Properties ◽  
Crystallite Size ◽  
Solvothermal Method ◽  
Hall Effect Measurement ◽  
Sulfur Source ◽  
Optical And Electrical Properties ◽  
Secondary Phases ◽  
Bulk Carrier ◽  
Noticeable Effect ◽  
P Type

Abstract In this study, the synthesis of Cu2SnS3 (CTS) nanoparticles by solvothermal method using different sulfur precursors is reported. The influence of sulfur precursors on the structure, optical and electrical properties of prepared CTS material is investigated. The sulfur precursor sources have showed a noticeable effect on crystallite size, secondary phases, and resulted CTS nanoparticles structure. Among the four sulfur precursor sources used in this study, thiourea is the only sulfur source that produces CTS with a cubic structure and without the need for thermal treatment. Whereas after sulfurization at 580 ºC, all the four samples attained CTS nanoparticles with diverse properties. Changing the sulfur precursors have clear effects on crystallite size and optical bandgap prepared samples as they ranged from 11.21 to 21.23 nm and from 1.4 to 1.7 eV, respectively. Additionally, Hall effect measurement revealed that all CTS samples are p-type semiconductors with bulk carrier concentrations in 1018 order, which is suitable for various optoelectronic applications such as photovoltaics and photodetectors.

Research on Thermal Stress of Slab Heating Process Based on Transient Non-Linear Analysis

2011 ◽  
Vol 311-313 ◽  
pp. 936-939
Author(s):  
Xiao Hang Wan ◽  
Zhao Wei Dong ◽  
Shu Jun Li ◽  
Sheng Yong Liu
Keyword(s):  
Electrical Properties ◽  
Linear Analysis ◽  
Heating Process ◽  
Deposition Method ◽  
Vertical Deposition ◽  
Grain Sizes ◽  
Vapor Phase Deposition ◽  
Structural And Electrical Properties ◽  
Vertical Deposition Method ◽  
Seed Layers

Polycrystalline α-HgI2 films have been grown through combining vertical deposition method with hot wall vapor phase deposition (HWPVD) method. The influence of the α-HgI2 seed layers on the structural and electrical properties of the polycrystalline α-HgI2 films was investigated. It is found that the α-HgI2 seed layers play an important role in reducing the grain sizes, increasing the density improving the crystallographic orientation and electrical properties of the polycrystalline α-HgI2 films.

Microstructure and Electrical Properties of Calcium Copper Titanate Ceramics

2007 ◽  
Vol 561-565 ◽  
pp. 551-555 ◽  
Author(s):  
Lai Jun Liu ◽  
Hui Qing Fan
Keyword(s):  
Electrical Properties ◽  
Dielectric Permittivity ◽  
High Frequency ◽  
Low Frequency ◽  
Wide Frequency Range ◽  
Frequency Range ◽  
Cell Parameters ◽  
Grain Sizes ◽  
Calcium Copper Titanate ◽  
Titanate Ceramics

The effect of stoichiometry, i.e. Ca/Cu ratios (CaCu3xTi4O12, x = 0.8, 0.9, 1.0, 1.1 and 1.2) on the microstructure and electrical properties was investigated. The grain sizes of CaCu3xTi4O12 composition increased sharply with the increase of copper, from ~1 μm with x = 0.8 to ~50 μm with x = 1.2. The real part of dielectric permittivity changed dramatically, the pellet with x = 1.0 had the highest dielectric permittivity ~160, 000 at 1 kHz. Furthermore, the dielectric permittivity of all pellets was impressively large values (between 10, 000 to 1, 000,000 at 100 Hz) and was nearly constant over a wide frequency range between 100 Hz to ~100 MHz. However, the dielectric permittivity of CaCu3xTi4O12 composition is not consistent with the amount of copper and cell parameters and grain sizes. Impedance spectroscopy exhibited that the CaCu3xTi4O12 composition had two semicircle at least at high frequency (~ 107 Hz) and low frequency (<100 Hz), respectively. The grain and grain boundary of the compositions had different impedance and relaxation behavior.

scholarly journals RESPIRATION AND GEOTROPISM IN VICIA FABA. I

1929 ◽  
Vol 12 (5) ◽  
pp. 641-667 ◽  
Author(s):  
A. E. Navez
Keyword(s):  
Experimental Data ◽  
Reaction Time ◽  
Vicia Faba ◽  
Temperature Characteristic ◽  
Oxidative Process ◽  
Similar Material ◽  
Oxidative Processes ◽  
Time Relation

In this paper there are given the results of a study of the relation of respiration to temperature, in seedlings of Vicia faba, and of the onset of geotropic response. It is shown that with due care and very accurate control of temperature constancy, one can get constant excretion of CO2 even over fairly long periods. The treatment of the experimental data shows that the Q10 ratio is of course a valueless "constant," as it is variable; but that the figure obtained for µ, the temperature characteristic (critical thermal increment), 16,250, is perfectly consistent with the values previously obtained for µ in respiratory oxidative processes in similar material. New data on the reaction time for the root of Vicia faba seedlings excited geotropically are given also. The study of the dependence of this time relation on temperature shows µ = 16,110, agreeing quantitatively with the value deduced previously from the relevant data of earlier investigators (Crozier, 1924). This points to the importance of some respiratory oxidative process as the agency controlling the onset of geotropic curvature.

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