Influence of powder size on thermoelectric properties of p-type 25%Bi2Te375%Sb2Te3 alloys fabricated using gas-atomization and spark-plasma sintering

Dharmaiah, Peyala; Kim, Hyo-Seob; Lee, Chulhee; Hong, Soon‐Jik

doi:10.1016/j.jallcom.2016.05.340

Cited by 50 publications

(28 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The mechanical strength of thermoelectric materials is important for preparation TE modules. The maximum Vickers hardness of 102 Hv was obtained for the EG-pH10 sintered sample, which is significantly higher or comparable to several reported results [14,20]. The obtained high hardness in the bulk sample was due to the presence of fine grains and increased amount of grain boundaries [20].…”

Section: Resultssupporting

confidence: 85%

Effect of Surfactant Addition on Bi2Te3 Nanostructures Synthesized by Hydrothermal Method

Dharmaiah

Lee

Madavali

et al. 2017

Archives of Metallurgy and Materials

Self Cite

View full text Add to dashboard Cite

In the present work, we have prepared Bi 2 Te 3 nanostructures with different morphologies such as nano-spherical, nanoplates and nanoflakes obtained using various surfactant additions (EG, PVP, and EDTA) by a hydrothermal method. The shape of the nanoparticles can be controlled by addition of surfactants. The samples were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that the minority BiOCl phase disappears after maintained pH at 10 with EG as surfactant. SEM bulk microstructure reveals that the sample consists of fine and coarse grains. Temperature dependence of thermoelectric properties of the nanostructured bulk sample was investigated in the range of 300-450K. The presence of nanograins in the bulk sample exhibits a reduction of thermal conductivity and less effect on electrical conductivity. As a result, a figure of merit of the sintered bulk sample reached 0.2 at 400 K. A maximum micro Vickers hardness of 102 Hv was obtained for the nanostructured sample, which was higher than the other reported results.

show abstract

Section: Resultssupporting

confidence: 85%

Effect of Surfactant Addition on Bi2Te3 Nanostructures Synthesized by Hydrothermal Method

Dharmaiah

Lee

Madavali

et al. 2017

Archives of Metallurgy and Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…In this report, the grain size increased with increasing powder size and, as a result, electrical conductivity was increased, due to increasing carrier mobility values. We obtained a maximum ZT of 1.2 with a 32-75 µm specimen due to the high power factor and reasonable thermal conductivity [20]. However, it is necessary to maintain an inert atmosphere in the gas atomization process, and the use of nitrogen and argon gasses is expensive.…”

Section: Introductionmentioning

confidence: 99%

Development of High-Performance Thermoelectric Materials by Microstructure Control of P-Type BiSbTe Based Alloys Fabricated by Water Atomization

et al. 2021

Self Cite

View full text Add to dashboard Cite

Developing inexpensive and rapid fabrication methods for high efficiency thermoelectric alloys is a crucial challenge for the thermoelectric industry, especially for energy conversion applications. Here, we fabricated large amounts of p-type Cu0.07Bi0.5Sb1.5Te3 alloys, using water atomization to control its microstructure and improve thermoelectric performance by optimizing its initial powder size. All the water atomized powders were sieved with different aperture sizes, of 32–75 μm, 75–125 μm, 125–200 μm, and <200 μm, and subsequently consolidated using hot pressing at 490 °C. The grain sizes were found to increase with increasing powder particle size, which also increased carrier mobility due to improved carrier transport. The maximum electrical conductivity of 1457.33 Ω−1 cm−1 was obtained for the 125–200 μm samples due to their large grain sizes and subsequent high mobility. The Seebeck coefficient slightly increased with decreasing particle size due to scattering of carriers at fine grain boundaries. The higher power factor values of 4.20, 4.22 × 10−3 W/mk2 were, respectively, obtained for large powder specimens, such as 125–200 μm and 75–125 μm, due to their higher electrical conductivity. In addition, thermal conductivity increased with increasing particle size due to the improvement in carriers and phonons transport. The 75–125 μm powder specimen exhibited a relatively high thermoelectric figure of merit, ZT of 1.257 due to this higher electric conductivity.

show abstract

“…Considering the difference of T m , T g ( Figure a) and thermal expansion coefficients (TEC) (Figure b) among materials as well as the construction of fiber preform (see the Supporting Information for details), we categorize typical functional materials in three distinct groups: high temperature group (cladding: silica; core: Si, Ge, Au, and Cu), medium temperature group (cladding: borosilicate; core: Bi 2 Te 3 ), and low temperature group (cladding: polymer; core: Se and chalcogenide glass). These fiber core materials cover most commonly used materials in photonics, electronics, optoelectronics, and thermoelectronics . Note the drawing temperatures of these groups range from 400 to 2400 K, and the viscosity ratios between the fiber core and fiber cladding vary from 10 −3 to 10 −12 .…”

Section: Resultsmentioning

confidence: 99%

Laser‐Induced In‐Fiber Fluid Dynamical Instabilities for Precise and Scalable Fabrication of Spherical Particles

Zhang

et al. 2017

Adv Funct Materials

View full text Add to dashboard Cite

Scalable fabrication of spherical particles at both the micro-and nanoscales is of significant importance for applications spanning optical devices, electronics, targeted drug delivery, biodevices, sensors, and cosmetics. However, current top-down and bottom-up fabrication methods are unable to provide the full spectrum of uniformly sized, well-ordered, and high-quality spheres due to their inherent restrictions. Here, a generic, scalable, and precisely controllable fabrication method is demonstrated for generating spherical particles in a full range of diameters from microscale to nanoscale. This method begins with a macroscopic composite multimaterial solid-state preform drawn into a fiber that defines precisely the initial conditions for the process. It is then followed by CO 2 laser heating to enable the transformation from a continuous fiber core into a series of homogeneous spheres via Plateau-Rayleigh capillary instability inside the fiber. This physical breakup method applies to a wide range of functional materials with different melting temperatures from 400 to 2400 K and 10 orders of difference in fiber core/cladding viscosity ratio. Furthermore, an ordered array of silicon-based whispering-gallery mode resonators with the Q factor as high as 7.1 × 10 5 is achieved, owing to the process induced ultrasmooth surface and highly crystalline nature.

show abstract

Influence of powder size on thermoelectric properties of p-type 25%Bi2Te375%Sb2Te3 alloys fabricated using gas-atomization and spark-plasma sintering

Cited by 50 publications

References 35 publications

Effect of Surfactant Addition on Bi2Te3 Nanostructures Synthesized by Hydrothermal Method

Effect of Surfactant Addition on Bi2Te3 Nanostructures Synthesized by Hydrothermal Method

Development of High-Performance Thermoelectric Materials by Microstructure Control of P-Type BiSbTe Based Alloys Fabricated by Water Atomization

Laser‐Induced In‐Fiber Fluid Dynamical Instabilities for Precise and Scalable Fabrication of Spherical Particles

Contact Info

Product

Resources

About