Vacancy engineering in rock-salt type (IV-VI)x(V-VI) materials for high thermoelectric performance

Min, Yuho; Kim, Minkyung; Hwang, Geon‐Tae; Ahn, Cheol‐Woo; Choi, Jong‐Jin; Hahn, Byung‐Dong; Yoon, Woon‐Ha; Moon, Geon Dae; Park, Chee-Sung; Park, Cheol‐Hee

doi:10.1016/j.nanoen.2020.105198

Cited by 18 publications

(11 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The true density of each sample was measured using a gas pycnometer based on gas replacement method. The theoretical density of the current study samples was calculated as ∼6.04 g/ cm 3 based on the mass ratio (80:0.25) and density (6.05 g/cm 3 , 3.95 g/cm 3 ) of 3YSZ and Al 2 O 3 . As the heat treatment temperature increased from 1200 to 1400 °C, the density of the samples increased as well (5.79 g/cm 3 , 5.95 g/cm 3 , and 5.99 g/cm 3 ), corresponding to the relative densities of 95.9%, 98.5%, and 99.2% (Figure 8a).…”

Section: Resultsmentioning

confidence: 99%

“…In particular, they can persist in an isolated form, which facilitates further processing for desired properties. For instance, heat treatment is essential for the synthesis or enhancement of desired properties exhibited by various nanoparticles, especially ceramic materials. − However, this process can result in the formation of hard agglomerates that cannot be easily separated. Thus, the formation of supraparticles is an alternative approach to avoid random agglomerations and improve their functional properties as isolated architectures.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Supraparticle Engineering for Highly Dense Microspheres: Yttria-Stabilized Zirconia with Adjustable Micromechanical Properties

et al. 2021

Self Cite

View full text Add to dashboard Cite

Various supraparticles have been extensively studied owing to their excellent catalytic properties that are attributed to their inherent porous structure; however, their mechanical properties have not garnered attention owing to their less dense structure. We demonstrate a rational approach for fabricating assembled supraparticles and, subsequently, highly dense microspheres. In addition, 3 mol % yttria-stabilized zirconia (3YSZ) and alumina particles were selected as building blocks and assembled into higher-order architectures using a droplet-based template method (spray drying) for validation with proof-of-concept. Moreover, structural features such as density, size, sphericity, and morphology of supraparticles were controlled by adjusting the competing kinetics occurring between the assembly of building blocks and evaporation of the solvent in the droplets. The preparatory aqueous suspension and process parameters were optimized as well. A detailed understanding of the formation mechanism facilitated the yield of tailor-made supraparticles and, thereafter, highly dense microspheres (approximate relative density = 99%) with excellent sphericity (>98%) via heat treatment. The microspheres displayed highest hardness (26.77 GPa) and superior elastic modulus (210.19 GPa) compared with the mechanical properties of the 3YSZ samples reported to date. Ultimately, the proposed supraparticle engineering provided insight for controlling the structural features and resultant micromechanical properties, which widely extends the applicability of supraparticle-based functional materials for practical purposes that require materials with high density and excellent mechanical properties.

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

Supraparticle Engineering for Highly Dense Microspheres: Yttria-Stabilized Zirconia with Adjustable Micromechanical Properties

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…These methods usually bring about a changed effective mass, band crossing, and additional channels for phonon scattering, and the synergistic effects can further enhance the peak zT to 1.85 at 823K [37]. In addition to controlling the electron transport, the introduction of crystal imperfections [38,39] and the inducement of soft modes [40] in SnTe can result in poor thermal conductivity. To date, there have been relatively few studies on n-type SnTe.…”

Section: Introductionmentioning

confidence: 99%

Simultaneous enhancement in electrical conductivity and Seebeck coefficient by single- to double-valley transition in a Dirac-like band

Liu

Yu²,

Zhou

et al. 2022

Preprint

View full text Add to dashboard Cite

Recently, n-type SnTe has been shown to be a promising thermoelectric material. It possesses a unique single- to double-valley transition in the conduction band when a compressive strain is applied. Through a tight-binding analysis, it is shown that the variation of the band structure is attributed to the strain-induced delocalization of both the Sn-5s orbitals and Te-5p orbitals with different angular momenta. This effect can largely increase the electron density of states near the band edge and thus keep the Fermi level of the compressed SnTe closer to it, where the electrons have lower scattering rates. The strain-induced double valleys lead to simultaneous increases in the electrical conductivity and the Seebeck coefficient and thereby nearly four times enhancement of the power factor at the doping concentration of 5×1019 cm–3. This work suggests a feasible concept that can be employed to promote the power factor of a Dirac semiconductor via manipulating the valley degeneracy in the conduction band minimum.

show abstract

“…These methods usually bring about a changed effective mass, band crossing, and additional channels for phonon scattering, and the synergistic effects can further enhance the peak zT to 1.85 at 823 K 37 . In addition to controlling the electron transport, the introduction of crystal imperfections 38,39 and the inducement of soft modes 40 in SnTe can result in poor thermal conductivity. To date, there have been relatively few studies on n-type SnTe.…”

Section: Introductionmentioning

confidence: 99%

Simultaneous enhancement in electrical conductivity and Seebeck coefficient by single- to double-valley transition in a Dirac-like band

et al. 2022

View full text Add to dashboard Cite

SnTe possesses a single- to double-valley transition in the conduction band minimum when a compressive strain is applied. Through a tight-binding analysis, it is shown that the variation of the band structure is attributed to the strain-induced delocalization of both the Sn-5s orbitals and Te-5p orbitals with different angular momenta. This effect can largely increase the electron density of states near the band edge and thus keep the Fermi level of the compressed SnTe closer to it, where the electrons have lower scattering rates. The strain-induced double valleys lead to simultaneous increases in the electrical conductivity and the Seebeck coefficient and thereby nearly four times the enhancement of the power factor at the doping concentration of 5×1019 cm–3. This work suggests a feasible concept that can be employed to promote the power factor of a Dirac semiconductor via manipulating the valley degeneracy in the conduction band minimum.

show abstract

Vacancy engineering in rock-salt type (IV-VI)x(V-VI) materials for high thermoelectric performance

Cited by 18 publications

References 53 publications

Supraparticle Engineering for Highly Dense Microspheres: Yttria-Stabilized Zirconia with Adjustable Micromechanical Properties

Supraparticle Engineering for Highly Dense Microspheres: Yttria-Stabilized Zirconia with Adjustable Micromechanical Properties

Simultaneous enhancement in electrical conductivity and Seebeck coefficient by single- to double-valley transition in a Dirac-like band

Simultaneous enhancement in electrical conductivity and Seebeck coefficient by single- to double-valley transition in a Dirac-like band

Contact Info

Product

Resources

About