Microstructure and Thermoelectric Properties of Thin Foils of Bismuth Telluride Alloys

1998 ◽  
Vol 545 ◽  
Author(s):  
E. Koukharenko ◽  
N. Frety ◽  
V. G. Shepelevich ◽  
J. C. Tedenac
Keyword(s):  
Physical Properties ◽  
Thermoelectric Properties ◽  
Bismuth Telluride ◽  
Polycrystalline Materials ◽  
The Past ◽  
Thin Foils ◽  
Ultrarapid Quenching

AbstractUltrarapid quenching processes have been extensively studied during the past few years. particularly for glasses. In the case of polycrystalline materials, the problem is slightly different. In this case, the microstructures obtained by this process are very different from those obtained by normal cooling and they induce new physical properties.

scholarly journals Direct measurement of the thermoelectric properties of electrochemically deposited Bi2Te3 thin films

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jose Recatala-Gomez ◽  
Pawan Kumar ◽  
Ady Suwardi ◽  
Anas Abutaha ◽  
Iris Nandhakumar ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermoelectric Properties ◽  
Bismuth Telluride ◽  
Indium Tin Oxide ◽  
Seed Layer ◽  
Room Temperature ◽  
Low Cost ◽  
Temperature Dependent ◽  
Temperature Heat ◽  
Electrochemically Deposited

Abstract The best known thermoelectric material for near room temperature heat-to-electricity conversion is bismuth telluride. Amongst the possible fabrication techniques, electrodeposition has attracted attention due to its simplicity and low cost. However, the measurement of the thermoelectric properties of electrodeposited films is challenging because of the conducting seed layer underneath the film. Here, we develop a method to directly measure the thermoelectric properties of electrodeposited bismuth telluride thin films, grown on indium tin oxide. Using this technique, the temperature dependent thermoelectric properties (Seebeck coefficient and electrical conductivity) of electrodeposited thin films have been measured down to 100 K. A parallel resistor model is employed to discern the signal of the film from the signal of the seed layer and the data are carefully analysed and contextualized with literature. Our analysis demonstrates that the thermoelectric properties of electrodeposited films can be accurately evaluated without inflicting any damage to the films.

Tailoring bismuth telluride nanostructures using a scalable sintering process and their thermoelectric properties

CrystEngComm ◽  
2014 ◽  
Vol 16 (34) ◽  
pp. 7956-7962 ◽  
Author(s):  
P. Anandan ◽  
M. Omprakash ◽  
M. Azhagurajan ◽  
M. Arivanandhan ◽  
D. Rajan Babu ◽  
...  
Keyword(s):  
Thermoelectric Properties ◽  
Bismuth Telluride ◽  
Sintering Process

The size and phase of bismuth telluride nanocrystals were tailored using a sintering process, to enhance their thermoelectric properties.

scholarly journals The properties of early-type stars in the Magellanic Clouds

2008 ◽  
Vol 4 (S256) ◽  
pp. 325-336
Author(s):  
Christopher J. Evans
Keyword(s):  
Physical Properties ◽  
Mass Loss ◽  
Temperature Scale ◽  
Massive Stars ◽  
Magellanic Clouds ◽  
Early Type ◽  
The Past ◽  
The Galaxy ◽  
Stellar Temperature ◽  
Early Type Stars

AbstractThe past decade has witnessed impressive progress in our understanding of the physical properties of massive stars in the Magellanic Clouds, and how they compare to their cousins in the Galaxy. I summarise new results in this field, including evidence for reduced mass-loss rates and faster stellar rotational velocities in the Clouds, and their present-day compositions. I also discuss the stellar temperature scale, emphasizing its dependence on metallicity across the entire upper-part of the Hertzsprung-Russell diagram.

LOW TEMPERATURE THERMOELECTRIC PROPERTIES AND AGING PHENOMENA OF NANOSTRUCTURED p-TYPE Bi2-XSbXTe3 (x = 1.46, 1.48, 1.52 AND 1.55)

2013 ◽  
Vol 06 (05) ◽  
pp. 1340008 ◽  
Author(s):  
DALE HITCHCOCK ◽  
YEN-LIANG LIU ◽  
YUFEI LIU ◽  
TERRY M. TRITT ◽  
JIAN HE ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Low Temperature ◽  
Thermoelectric Properties ◽  
Optimal Composition ◽  
Ambient Conditions ◽  
Bulk Materials ◽  
The Past ◽  
Aging Phenomena ◽  
P Type ◽  
Cold Pressed

Over the past decade the widely used p-type ( Bi 2-x Sb x) Te 3 bulk thermoelectric materials have been subject to various nanostructuring processes for higher thermoelectric performance. However, these nanostructuring processing were conducted on compositions optimized for bulk materials (x ~ 1.52–1.55). This leads to the question of whether the optimal composition for bulk materials is the same for their nanoscale counterparts. In this work we hydrothermally grew Bi 2-x Sb x Te 3 nanopowders (nominally, x = 1.46, 1.48, 1.52 and 1.55) and measured their thermoelectric properties on cold-pressed vacuum-sintered pellets (74–78% of the theoretical density) below 300 K. The measurements were conducted 18 months apart to probe the aging phenomena, with the samples stored in ambient conditions. We have found that (i) the peak of thermopower shifts to lower temperatures upon nanostructuring but it shifts back to higher temperatures upon aging; (ii) the electrical conductivity degrades by a factor of 1.5–2.3 upon aging while the temperature dependence is largely retained; and (iii) the ZT of freshly made samples is sensitive to the x value, a maximum ZT ~ 1.25(~ 0.62) at ~ 270 K (~ 255 K) was attained in the freshly made sample x = 1.55(x = 1.46), respectively; while the ZT of aged samples is significantly lowered by a factor of 2–4 but lesser x-dependent. These observations have been discussed in the context of charge buildup and compensation at grain boundaries.

scholarly journals Kekasaran Permukaan Resin Komposit Nanofilled dan Nanohybrid Setelah Paparan Asap Rokok Kretek

2019 ◽  
Vol 8 (1) ◽  
pp. 30
Author(s):  
Johanna Chandra ◽  
Laksmiari Setyowati ◽  
Setyabudi Setyabudi
Keyword(s):  
Surface Roughness ◽  
Physical Properties ◽  
Cigarette Smoke ◽  
Public Health Problem ◽  
Composite Resins ◽  
Dental Composites ◽  
Distilled Water ◽  
Control Groups ◽  
The Past ◽  
Nanohybrid Composite

Background: Cigarette smoking is a public health problem that may influence physical properties of dental composites. Surface roughness is one of the physical properties of restorative materials that can influence their success. The use of nanofilled and nanohybrid composites in dentistry has substantially increased over the past few years. Purpose: The purpose of this study was to evaluate the surface roughness of nanofilled and nanohybrid composite resins exposed to kretek cigarette smoke. Methods: Twelve cylindrical specimens were prepared of each material and divided into two groups (n=6). For the control groups, the specimens were immersed in distilled water for 24 hours at 37oC and the water was renewed daily. For the experimental groups, the specimens were exposed daily to kretek cigarette smoke, then washed and stored in distilled water at 37oC. After 21 days, specimens were measured using a Surface Roughness Tester and the data was statistically analyzed. Result: Independent-T Test revealed that there were statistically significant differences in the surface roughness between control and experimental groups both nanofilled and nanohybrid, and between experimental groups nanofilled and nanohybrid. Conclusion: The exposure to kretek cigarette smoke can significantly increase the surface roughness of nanohybrid composites more than nanofilled composites.

scholarly journals Coated Metal Powders for Laser Powder Bed Fusion (L-PBF) Processing: A Review

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1831
Author(s):  
Robert Bidulsky ◽  
Federico Simone Gobber ◽  
Jana Bidulska ◽  
Marta Ceroni ◽  
Tibor Kvackaj ◽  
...  
Keyword(s):  
Physical Properties ◽  
Powder Bed Fusion ◽  
Metal Powders ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
The Past ◽  
Coated Metal ◽  
Mechanical And Physical Properties ◽  
Interesting Approach ◽  
Coating Methods

In the last years, functionalized powders are becoming of increasing interest in additive manufacturing (particularly in laser powder bed fusion processing, L-PBF), due to their improved flowability and enhanced processability, particularly in terms of laser absorbance. Functionalized powders may also provide higher final mechanical or physical properties in the manufactured parts, like an increased hardness, a higher tensile strength, and density levels close to theoretical. Coatings represent a possible interesting approach for powders’ functionalizing. Different coating methods have been studied in the past years, either mechanical or non-mechanical. This work aims to present an overview of the currently obtained coated powders, analyzing in detail the processes adopted for their production, the processability of the coated systems, and the mechanical and physical properties of the final parts obtained by using L-PBF for the powders processing.

Sign in / Sign up

Export Citation Format

Share Document