p-Type to n-Type Conversion through the “Bypass” Phase Transition in the Zintl-Phase Thermoelectric Materials

2021 ◽  
Author(s):  
Seongbeom Yeon ◽  
Seungeun Shin ◽  
Hongil Jo ◽  
Nguyen Le Thi ◽  
Dohyun Moon ◽  
...  
Keyword(s):  
Phase Transition ◽  
Thermoelectric Materials ◽  
Type Conversion ◽  
Zintl Phase ◽  
P Type

Significantly enhanced thermoelectric figure of merit of p-type Mg3Sb2-based Zintl phase compounds via nanostructuring and employing high energy mechanical milling coupled with spark plasma sintering

2015 ◽  
Vol 3 (20) ◽  
pp. 10777-10786 ◽  
Author(s):  
A. Bhardwaj ◽  
N. S. Chauhan ◽  
D. K. Misra
Keyword(s):  
Thermoelectric Materials ◽  
Mechanical Milling ◽  
Figure Of Merit ◽  
High Energy ◽  
Thermoelectric Figure Of Merit ◽  
Zintl Phase ◽  
Thermoelectric Figure ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
P Type

Several nanostructuring methods have been demonstrated to produce a variety of nanostructured materials, and these methods are well recognized as effective paradigms for improving the performance of thermoelectric materials.

p‐Type Plastic Inorganic Thermoelectric Materials

2021 ◽  
pp. 2100883
Author(s):  
Zhiqiang Gao ◽  
Qingyu Yang ◽  
Pengfei Qiu ◽  
Tian‐Ran Wei ◽  
Shiqi Yang ◽  
...  
Keyword(s):  
Thermoelectric Materials ◽  
P Type

scholarly journals The origin of the lattice thermal conductivity enhancement at the ferroelectric phase transition in GeTe

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Đorđe Dangić ◽  
Olle Hellman ◽  
Stephen Fahy ◽  
Ivana Savić
Keyword(s):  
Phase Transition ◽  
Thermal Conductivity ◽  
Phase Transitions ◽  
Thermoelectric Materials ◽  
Ferroelectric Phase Transition ◽  
Lattice Thermal Conductivity ◽  
Ferroelectric Phase ◽  
Structural Phase ◽  
High Symmetry ◽  
Structural Phase Transitions

AbstractThe proximity to structural phase transitions in IV-VI thermoelectric materials is one of the main reasons for their large phonon anharmonicity and intrinsically low lattice thermal conductivity κ. However, the κ of GeTe increases at the ferroelectric phase transition near 700 K. Using first-principles calculations with the temperature dependent effective potential method, we show that this rise in κ is the consequence of negative thermal expansion in the rhombohedral phase and increase in the phonon lifetimes in the high-symmetry phase. Strong anharmonicity near the phase transition induces non-Lorentzian shapes of the phonon power spectra. To account for these effects, we implement a method of calculating κ based on the Green-Kubo approach and find that the Boltzmann transport equation underestimates κ near the phase transition. Our findings elucidate the influence of structural phase transitions on κ and provide guidance for design of better thermoelectric materials.

Fabrication of Bi-Te Based Thermoelectric Semiconductors by Using Hybrid Powders

2005 ◽  
Vol 297-300 ◽  
pp. 875-880
Author(s):  
Cheol Ho Lim ◽  
Ki Tae Kim ◽  
Yong Hwan Kim ◽  
Dong Choul Cho ◽  
Young Sup Lee ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Single Crystals ◽  
Thermoelectric Properties ◽  
Thermoelectric Materials ◽  
Figure Of Merit ◽  
Bending Strength ◽  
Mixing Ratio ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
P Type

P-type Bi0.5Sb1.5Te3 compounds doped with 3wt% Te were fabricated by spark plasma sintering and their mechanical and thermoelectric properties were investigated. The sintered compounds with the bending strength of more than 50MPa and the figure-of-merit 2.9×10-3/K were obtained by controlling the mixing ratio of large powders (PL) and small powders (PS). Compared with the conventionally prepared single crystal thermoelectric materials, the bending strength was increased up to more than three times and the figure-of-merit Z was similar those of single crystals. It is expected that the mechanical properties could be improved by using hybrid powders without degradation of thermoelectric properties.

1-2-2 Layered Zintl-Phase Thermoelectric Materials

2019 ◽  
pp. 159-175
Author(s):  
Jing Shuai ◽  
Shan Li ◽  
Chen Chen ◽  
Xiaofang Li ◽  
Jun Mao ◽  
...  
Keyword(s):  
Thermoelectric Materials ◽  
Zintl Phase

scholarly journals Effect of Microwave Processing and Glass Inclusions on Thermoelectric Properties of P-Type Bismuth Antimony Telluride Alloys for Wearable Applications

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4524
Author(s):  
Amin Nozariasbmarz ◽  
Daryoosh Vashaee
Keyword(s):  
Seebeck Coefficient ◽  
Thermoelectric Materials ◽  
Room Temperature ◽  
Electronic Devices ◽  
Microwave Processing ◽  
Glass Inclusion ◽  
Wearable Electronic ◽  
P Type ◽  
Wearable Electronic Devices ◽  
Body Heat

Depending on the application of bismuth telluride thermoelectric materials in cooling, waste heat recovery, or wearable electronics, their material properties, and geometrical dimensions should be designed to optimize their performance. Recently, thermoelectric materials have gained a lot of interest in wearable electronic devices for body heat harvesting and cooling purposes. For efficient wearable electronic devices, thermoelectric materials with optimum properties, i.e., low thermal conductivity, high Seebeck coefficient, and high thermoelectric figure-of-merit (zT) at room temperature, are demanded. In this paper, we investigate the effect of glass inclusion, microwave processing, and annealing on the synthesis of high-performance p-type (BixSb1−x)2Te3 nanocomposites, optimized specially for body heat harvesting and body cooling applications. Our results show that glass inclusion could enhance the room temperature Seebeck coefficient by more than 10% while maintaining zT the same. Moreover, the combination of microwave radiation and post-annealing enables a 25% enhancement of zT at room temperature. A thermoelectric generator wristband, made of the developed materials, generates 300 μW power and 323 mV voltage when connected to the human body. Consequently, MW processing provides a new and effective way of synthesizing p-type (BixSb1−x)2Te3 alloys with optimum transport properties.

scholarly journals Prediction of 10-fold coordinated TiO2 and SiO2 structures at multimegabar pressures

2015 ◽  
Vol 112 (22) ◽  
pp. 6898-6901 ◽  
Author(s):  
Matthew J. Lyle ◽  
Chris J. Pickard ◽  
Richard J. Needs
Keyword(s):  
Phase Transition ◽  
Phase Transitions ◽  
Electronic Properties ◽  
First Principles ◽  
Pressure Range ◽  
Extrasolar Planets ◽  
Equations Of State ◽  
Space Group ◽  
P Type ◽  
Pressure Phase

We predict by first-principles methods a phase transition in TiO2 at 6.5 Mbar from the Fe2P-type polymorph to a ten-coordinated structure with space group I4/mmm. This is the first report, to our knowledge, of the pressure-induced phase transition to the I4/mmm structure among all dioxide compounds. The I4/mmm structure was found to be up to 3.3% denser across all pressures investigated. Significant differences were found in the electronic properties of the two structures, and the metallization of TiO2 was calculated to occur concomitantly with the phase transition to I4/mmm. The implications of our findings were extended to SiO2, and an analogous Fe2P-type to I4/mmm transition was found to occur at 10 TPa. This is consistent with the lower-pressure phase transitions of TiO2, which are well-established models for the phase transitions in other AX2 compounds, including SiO2. As in TiO2, the transition to I4/mmm corresponds to the metallization of SiO2. This transformation is in the pressure range reached in the interiors of recently discovered extrasolar planets and calls for a reformulation of the equations of state used to model them.

Structure Design for High Performance n-Type Polymer Thermoelectric Materials

2021 ◽  
Author(s):  
Qi Zhang ◽  
Hengda Sun ◽  
Meifang Zhu
Keyword(s):  
Conjugated Polymers ◽  
Thermoelectric Materials ◽  
High Performance ◽  
Waste Heat ◽  
Building Blocks ◽  
Structure Design ◽  
Potential Candidate ◽  
Polymer Backbone ◽  
P Type ◽  
Polymer Thermoelectric

Abstract Organic thermoelectric (OTE) materials have been regarded as a potential candidate to harvest waste heat from complex, low temperature surfaces of objects and convert it into electricity. Recently, n-type conjugated polymers as organic thermoelectric materials have aroused intensive research in order to improve their performance to match up with their p-type counterpart. In this review, we discuss aspects that affect the performance of n-type OTEs, and further focus on the effect of planarity of backbone on doping efficiency and eventually the TE performance. We then summarize strategies such as implementing rigid n-type polymer backbone or modifying conventional polymer building blocks for more planar conformation. In the outlook part, we conclude forementioned devotions and point out new possibility that may promote the future development of this field.

scholarly journals Substitution Versus Full-Heusler Segregation in TiCoSb

Metals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 935 ◽  
Author(s):  
Maryana Asaad ◽  
Jim Buckman ◽  
Jan-Willem Bos
Keyword(s):  
Powder Metallurgy ◽  
Power Factor ◽  
Thermoelectric Materials ◽  
Room Temperature ◽  
The Difference ◽  
P Type ◽  
Full Heusler ◽  
Thermal Conductivities

Half-Heuslers (HHs) are promising thermoelectric materials with great compositional flexibility. Here, we extend work on the p-type doping of TiCoSb using abundant elements. Ti0.7V0.3Co0.85Fe0.15Sb0.7Sn0.3 samples with nominal 17.85 p-type electron count were investigated. Samples prepared using powder metallurgy have negative Seebeck values, S ≤ −120 µV K−1, while arc-melted compositions are compensated semiconductors with S = −45 to +30 µV K−1. The difference in thermoelectric response is caused by variations in the degree of segregation of V(Co0.6Fe0.4)2Sn full-Heusler and Sn phases, which selectively absorb V, Fe, and Sn. The segregated microstructure leads to reduced lattice thermal conductivities, κlat = 4.5−7 W m−1 K−1 near room temperature. The largest power factor, S2/ρ = 0.4 mW m−1 K−2 and ZT = 0.06, is observed for the n-type samples at 800 K. This works extends knowledge regarding suitable p-type dopants for TiCoSb.

Sign in / Sign up

Export Citation Format

Share Document