N-type Ba0.2Co4Sb11.5Te0.5: Optimization of thermoelectric properties by different pressures

2019 ◽  
Vol 33 (03) ◽  
pp. 1950027 ◽  
Author(s):  
Jiaxiang Chen ◽  
Xiaopeng Jia ◽  
Yuewen Zhang ◽  
Haiqiang Liu ◽  
Baomin Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Seebeck Coefficient ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Absolute Value ◽  
X Ray ◽  
Coefficient Increase ◽  
Maximum Power Factor ◽  
Scanning Electron

The polycrystalline skutterudite [Formula: see text] were successfully synthesized from 1.5 GPa to 3.5 GPa by the high pressure and high temperature (HPHT) method. Negative Seebeck coefficient confirmed the n-type conductivity of all samples. The phase compositions of samples were investigated by X-ray diffraction (XRD) and the microstructures were observed by scanning electron microscopy (SEM). It was found that the grains appeared smaller and the grain boundaries became more abundant when pressures were higher. We measured the electrical properties from room temperature to 723 K. Both the electrical resistivity and absolute value of Seebeck coefficient increase with the increasing synthetic pressure. At 723 K, the maximum power factor of [Formula: see text] was obtained for the sample synthesized under 3 GPa. The maximum ZT value of 0.61 was reached by [Formula: see text] synthesized under 3 GPa and measured at 723 K.

Influence of Inorganic Ion on the Synthesis of Hollow Calcium Carbonate

2006 ◽  
Vol 11-12 ◽  
pp. 677-680 ◽  
Author(s):  
Gunawan Hadiko ◽  
Yong Sheng Han ◽  
Masayoshi Fuji ◽  
Minoru Takahashi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Carbonate ◽  
Room Temperature ◽  
Hollow Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inorganic Ion ◽  
Potential Component ◽  
Scanning Electron

Hollow calcium carbonate (CaCO3) particles were synthesized by bubbling CO2 in the solution of calcium chloride (CaCl2) with the presence of ammonia at room temperature. Hollow calcium carbonate is a potential component to be used as pharmaceuticals, agrochemicals, and catalysis. This paper investigated the effect of additive on the hollow structure. In this study was used vanadate ion as additive agent. Physical characteristics of precipitate were evaluated using scanning electron microscopy (SEM) and X-ray diffraction (XRD).

THE BULK NANOCRYSTALLINE ZN PRODUCED BY MECHANICAL ATTRITION

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1548-1552
Author(s):  
X. K. ZHU ◽  
K. Y. ZHAO ◽  
C. J. LI ◽  
J. M. TAO ◽  
T. L. CHAN ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Microstructural Evolution ◽  
Tensile Testing ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mechanical Attrition ◽  
Bulk Nanocrystalline ◽  
Scanning Electron

The purpose of experiment was to produce bulk nanocrystalline Zn by mechanical attrition. The bulk nanocrystalline Zn produced by mechanical attrition was studied. The microstructural evolution during cryomilling and subsequent room temperature milling was characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). In this paper, Nanocrystalline Zn was produced by insitu consolidation of Zn elemental powder using mechanical attrition at liquid nitrogen and room temperature. For the samples studied, the longest elongation of 65% and highest stress of 200 MPa is obtained in nanocrystalline Zn during tensile testing at the condition of strain rate (10-3 sec-1) and 20°C which is equal to 0.43 Tm (Tm is the melting temperature of pure Zn ).

scholarly journals Fabrication and magnetic properties of hierarchical nickel microwires with nanothorns

2010 ◽  
Vol 8 (2) ◽  
pp. 434-439 ◽  
Author(s):  
Junhao Zhang ◽  
Ling Yang ◽  
Xiaofang Cheng ◽  
Jinmeng Zhang ◽  
Fucai Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Magnetic Properties ◽  
Room Temperature ◽  
Cooperative Effect ◽  
Magnetic Interactions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

AbstractHierarchical nickel microwires with nanothorns were fabricated through a reduction of nickelous salt with hydrazine in diethanolamine. The product was characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). The growth mechanism of the nickel microwires with nanothorns is proposed, based on the evolution of the structures and morphologies, which could be ascribed to the cooperative effect of the complexant of diethanolamine and inherent magnetic interactions. Magnetic properties of the product were measured at room temperature and compared with other shaped counterparts.

Effect of Selenium on Structure and Electrical Property for Bi0.4Sb1.6Se3xTe3(1-x) Novel Hexagonal Rods

2013 ◽  
Vol 756 ◽  
pp. 80-84
Author(s):  
Arej Kadhim ◽  
Arshad Hmood ◽  
Abu Hassan Haslan
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Rhombohedral Phase ◽  
Orthorhombic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Power Factor ◽  
Microscopy Images ◽  
Scanning Electron

Novel hexagonal rods of Bi0.4Sb1.6Se3xTe3(1-x) (0.0≤x≤1.0) were synthesized successfully through solid-state microwave synthesis. These hexagonal rods were explored using field emission scanning electron microscopy images. The X-ray diffraction results indicate that the powders (0.0≤x≤0.8) can be indexed as the rhombohedral phase, whereas the sample with x=1.0 has an orthorhombic phase structure. The electrical conductivity gradually decreases as Se increased, resulting in an increase in the Seebeck coefficient. Ascribing to the increased Seebeck coefficient for the sample with x=0.8, the maximum power factor is 7.47 mW/mK2 at 373 K.

Influence of Titanium Sol on the Sintering Behaviour, Microstructure and Properties of Al2O3-SiO2 Ceramic Cores

2013 ◽  
Vol 745-746 ◽  
pp. 507-511
Author(s):  
Jun Chen ◽  
Yue Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Flexural Strength ◽  
Room Temperature ◽  
Formation Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mullite Phase ◽  
Sintering Behaviour ◽  
Scanning Electron

A series of Al2O3-SiO2 ceramic cores with titanium sol sintered at 1350, 1450, 1500 and 1550for 2h, respectively, were prepared, and the phase and microstructure were characterized by X-ray Diffraction and Scanning Electron Microscopy. The influence of titanium sol on the phase transformation, shrinkage rate and flexural strength at room temperature has been investigated. The mullite phase formation temperature decreased by at least 150with the addition of 1wt% to 5wt% TiO2. Additionally, the titania additive promoted the combination of Al2O3 and SiO2, producing mullite phase which reduced the shrinkage and improved the flexural strength.

scholarly journals STUDY ON CATALYTIC ACTIVITY OF TIO2/SIO2, IN THE OXIDATION OF STYRENE

2009 ◽  
Vol 12 (3) ◽  
pp. 77-84
Author(s):  
Thao Tien Nguyen ◽  
Ngoan Thi Nguyen ◽  
Long Van Dang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Catalytic Activity ◽  
Ir Spectroscopy ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mild Conditions ◽  
Scanning Electron

All TiO2/SiO2 samples were prepared by the impregnation of Ti(i-PrO)4 in isopropanol at room temperature followed drying and calcination. The solids were characterized by several techniques including X- ray diffraction (XRD), IR spectroscopy, Scanning Electron Microscopy (SEM). No reflection lines of TiO2 are detected at a low content of TiO2 (< 7%), but are more visible at a higher concentration. The catalysts are tested in the liquid oxidation of styrene under mild conditions, producing mainly benzaldehyde. The effects of variables on the catalytic activity are also investigated.

Preparation of TI-Ba-Ca-Cu Superconducting Oxide Films by Spray Pyrolysis Technique

1991 ◽  
Vol 226 ◽  
Author(s):  
H.S. Koo ◽  
T.L. Kuo ◽  
D.H. Kuo ◽  
R.J. Lin ◽  
W.H. Lee ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Spray Pyrolysis ◽  
Room Temperature ◽  
Spray Pyrolysis Technique ◽  
Superconducting Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zero Resistance ◽  
Scanning Electron

AbstractSuperconducting TI-Ba-Ca-Cu-O(TBCCO) films with zero resistance temperatures above 100K have been prepared on (001)MgO single-crystal substrates by the combination techniques of spray pyrolysis and Tl-diffusion. The as-sprayed Ba-Ca-Cu-O films and the sintered TBCCO superconducting bulks were wrapped in Au foil and heated in oxygen at temperatures ranging from 890 to 920°C and cooled to room temperature by furnace cooling. Highly c-axis oriented superconducting films were obtained and their average thicknesses were about 5-10 μm. The characteristics of TBCCO films by X-ray diffraction, scanning electron microscopy and electrical property are discussed.

Preparation and Photocatalytic Properties of Bi2WO6 with Different Morphologies

2013 ◽  
Vol 779-780 ◽  
pp. 390-393
Author(s):  
Ying Chen ◽  
Xu Wang ◽  
Hua Song ◽  
Hua Lin Song
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Photocatalytic Activity ◽  
Catalytic Activity ◽  
Room Temperature ◽  
Great Influence ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphology And Structure ◽  
Scanning Electron

Bismuth tungstate (Bi2WO6) microcrystalline with different surfactant were successfully prepared by a facile hydrothermal route.The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and BrunauerEmmettTeller surface area (BTE) in detail. The photocatalytic activity of the samples was also evaluated using the degradation of Rh B at room temperature under visible light irradiation. It was found that the surfactant played important roles in the formation process of controlling the morphology and structure of the catalyst and also had a great influence on the catalytic activity. SDS and CTAB effectively improved the catalytic activity and PVP was good at controlling morphologies.

scholarly journals INFLUENCE OF THE ANNEALING TEMPERATURE ON STRUCTURE PROPERTIES AND PHOTOACTIVITY OF TITANIA COATING ON PHOSPHATE SURFACE

2010 ◽  
Vol 13 (1) ◽  
pp. 10-16
Author(s):  
Linh Thi Truc Nguyen ◽  
Tri Huu Nguyen ◽  
Dzung Van Nguyen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Methylene Blue ◽  
Room Temperature ◽  
Annealing Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Titania Coating ◽  
Scanning Electron ◽  
Structure Properties

The titania coating on phosphate surface was made by the painting method in air and at room temperature. The coatings were dried at 25°c and sintered at 15(TC, 25(FC, 350”C, 45ƠJC, 550°C for 30 minutes. X-ray diffraction, scanning electron microscopy and the cutting method (TCVN 2097-1993) were used to characterize the coatings. The results showed that the coating annealed at 350TC had the high photoactivity in the photodegradation of methylene blue.

Structural and Thermoelectric Properties of Bi0.4Sb1.6Se3xTe3(1-X) Quaternary Compound

2012 ◽  
Vol 620 ◽  
pp. 55-59
Author(s):  
Arej Kadhim ◽  
Arshad Hmood ◽  
Abu Hassan Haslan
Keyword(s):  
Electron Microscopy ◽  
Seebeck Coefficient ◽  
Rhombohedral Phase ◽  
Orthorhombic Phase ◽  
X Ray Diffraction ◽  
Quaternary Compound ◽  
X Ray ◽  
Maximum Power Factor ◽  
Microscopy Images ◽  
Scanning Electron

Novel hexagonal rods of Bi0.4Sb1.6Se3xTe3(1-x) (0.0x1.0) were synthesized successfully through solid-state microwave synthesis. These hexagonal rods were explored using field emission scanning electron microscopy images. The X-ray diffraction results indicate that the powders (0.0x0.8) can be indexed as the rhombohedral phase, whereas the sample with x=1.0 has an orthorhombic phase structure. The electrical conductivity gradually decreases as Se increased, resulting in an increase in the Seebeck coefficient. Ascribing to the increased Seebeck coefficient for the sample with x=0.8, the maximum power factor is 7.47 mW/mK2 at 373 K.

Sign in / Sign up

Export Citation Format

Share Document