Crystal structure and phase transition of thermoelectric SnSe

Sist, Mattia; Zhang, Jiawei; Iversen, Bo B.

doi:10.1107/s2052520616003334

Cited by 82 publications

(80 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…High temperature β-SnSe (~800 K < T < 1134 K) has an orthogonal structure with lattice parameters of a = 4.31 Å, b = 11.71 Å, and c = 4.42 Å and a space group of Cmcm (#63) for [98]. and Se atoms [71].…”

Section: α-Snse and β-Snsementioning

confidence: 99%

High-performance SnSe thermoelectric materials: Progress and future challenge

Chen

Zhao

Zou

2018

Progress in Materials Science

457

410

View full text Add to dashboard Cite

Thermoelectric materials offer an alternative opportunity to tackle the energy crisis and environmental problems by enabling the direct solid-state energy conversion. As a promising candidate with full potentials for the next generation thermoelectrics, tin selenide (SnSe) and its associated thermoelectric materials have been attracted extensive attentions due to their ultralow thermal conductivity and high electrical transport performance (power factor). To provide a thorough overview of recent advances in SnSe-based thermoelectric materials that have been revealed as promising thermoelectric materials since 2014, here, we first focus on the inherent relationship between the structural characteristics and the supreme thermoelectric performance of SnSe, including the thermodynamics, crystal structures, and electronic structures. The effects of phonon scattering, pressure or strain, and oxidation behavior on the thermoelectric performance of SnSe are discussed in detail. Besides, we summarize the current theoretical calculations to predict and understand the thermoelectric performance of SnSe, and provide a comprehensive summary on the current synthesis, characterization, and thermoelectric performance of both SnSe crystals and polycrystals, and their associated materials. In the end, we point out the controversies, challenges and strategies toward future enhancements of the SnSe thermoelectric materials.

show abstract

Section: α-Snse and β-Snsementioning

confidence: 99%

High-performance SnSe thermoelectric materials: Progress and future challenge

Chen

Zhao

Zou

2018

Progress in Materials Science

457

410

View full text Add to dashboard Cite

show abstract

“…To evaluate the influence of Sn vacancies on the thermoelectric performance of SnSe, the main temperature‐dependent properties for Sn 0.998 Se, Sn 0.992 Se, and Sn 0.981 Se along ⊥ direction (perpendicular to sintering pressure) are compared,22,24 including σ, S , S 2 σ, p , μ, κ, κ l , and ZT, respectively. Figure shows the results, in which the green dashed lines stand for theoretical phase transition temperature at ≈800 K 86,236,303–305. Figure 8a shows temperature‐dependent σ.…”

Section: Vacancy Engineeringmentioning

confidence: 99%

“…To evaluate the influence of Sn vacancies on the thermoelectric performance of SnSe, the main temperature-dependent properties for Sn 0.998 Se, Sn 0.992 Se, and Sn 0.981 Se along ⊥ direction (perpendicular to sintering pressure) are compared, [22,24] including σ, S, S 2 σ, p, μ, κ, κ l , and ZT, respectively. Figure 8 shows the results, in which the green dashed lines stand for theoretical phase transition temperature at ≈800 K. [86,236,[303][304][305] Figure 8a shows temperature-dependent σ. Compared with Sn 0.998 Se fabricated through traditional melting routes, Sn 0.981 Se fabricated through solvothermal route has significantly higher σ, derived from extra holes caused by the Sn vacancies, and in turn contributing to higher p. [3,25] Figure 8b shows temperature-dependent S, in which peak S values can be achieved at the bipolar-effect temperature T*.…”

Section: Electrical Transportationmentioning

confidence: 99%

High‐Performance Thermoelectric SnSe: Aqueous Synthesis, Innovations, and Challenges

2020

View full text Add to dashboard Cite

Tin selenide (SnSe) is one of the most promising candidates to realize environmentally friendly, cost‐effective, and high‐performance thermoelectrics, derived from its outstanding electrical transport properties by appropriate bandgaps and intrinsic low lattice thermal conductivity from its anharmonic layered structure. Advanced aqueous synthesis possesses various unique advantages including convenient morphology control, exceptional high doping solubility, and distinctive vacancy engineering. Considering that there is an urgent demand for a comprehensive survey on the aqueous synthesis technique applied to thermoelectric SnSe, herein, a thorough overview of aqueous synthesis, characterization, and thermoelectric performance in SnSe is provided. New insights into the aqueous synthesis‐based strategies for improving the performance are provided, including vacancy synergy, crystallization design, solubility breakthrough, and local lattice imperfection engineering, and an attempt to build the inherent links between the aqueous synthesis‐induced structural characteristics and the excellent thermoelectric performance is presented. Furthermore, the significant advantages and potentials of an aqueous synthesis route for fabricating SnSe‐based 2D thermoelectric generators, including nanorods, nanobelts, and nanosheets, are also discussed. Finally, the controversy, strategy, and outlook toward future enhancement of SnSe‐based thermoelectric materials are also provided. This Review guides the design of thermoelectric SnSe with high performance and provides new perspectives as a reference for other thermoelectric systems.

show abstract

“…Figure 7e shows the plots of κ l as a function of 1000/T for pellets, and all the plots show a linear relationship, indicating that the phonon scattering is dominated by Umklapp phonon scattering. [90,91] Considered that SnSe has ultralow κ l resulted from the strong bonding anharmonicity [38,91] caused by the long-range resonant network of Se p-bonds coupled to active Sn 5s orbitals, [92][93][94][95][96] as well as the observed crystal defects such as the lattice distortions, dislocations, crystal bent, and grain boundaries or interfaces, [24,97] such low κ l values are reasonable. Figure 7f shows the calculated κ l /κ ratio for our pellets, in which κ l contributes 55% of κ in the entire temperature range, indicating that phonon transport is significant for κ.…”

Section: Thermoelectric Performancementioning

confidence: 99%

Realizing High Thermoelectric Performance in n‐Type Highly Distorted Sb‐Doped SnSe Microplates via Tuning High Electron Concentration and Inducing Intensive Crystal Defects

Shi

Zheng

Liu

et al. 2018

Advanced Energy Materials

128

View full text Add to dashboard Cite

figure of merit (ZT) is defined as ZT = S 2 σT/κ = S 2 σT/(κ e +κ l ), where S, σ, κ, κ e , κ l , and T are the Seebeck coefficient, the electrical conductivity, the total thermal conductivity, the electrical thermal conductivity, the lattice thermal conductivity, and the absolute temperature, respectively. [3,5] A high powder factor (S 2 σ) and a low κ are required to achieve a high ZT value. [6][7][8] So far, significant efforts have been devoted to enhancing S 2 σ and/or reduce κ. [9] For the strategies of achieving high S 2 σ, resonant state doping, [10][11][12] band converging, [13][14][15][16] minority carrier blocking, [17,18] and quantum confinement [19][20][21] were designed and developed. For reducing κ, the strategies of nanostructuring, [22][23][24][25] hierarchical architecturing, [26][27][28] and nanoprecipitate inducing [29][30][31] were successfully adopted.Tin selenide (SnSe) is a typical semiconductor with a narrow bandgap of ≈0.9 eV, [32][33][34] making it a good candidate with great potentials for applications in low-cost thermoelectrics. [35][36][37] A remarkable high peak ZT of ≈2.6 at 923 K was reported in the p-type SnSe single crystals, [38] and a relative high ZT of ≈2.2 at 773 K was also achieved from the n-type Bi-doped SnSe single crystals, [39] both along their b-axes. Such high ZT values come from their ultralow κ (both <0.3 W m −1 K −1 at 773 K). [38,39] However, suffered from their poor mechanical properties, rigid crystal growth conditions, and high production cost, SnSe single crystals are difficult to be employed in practical thermoelectric devices, and the techniques used for growing single crystals are limited for repeatable and industrial scale-up. [40] To overcome these challenges, polycrystalline SnSe has become a research topic. To synthesize polycrystalline SnSe, various methods have been explored, such as melting, [40][41][42] arc-melting, [43,44] mechanical alloying, [45][46][47] solid state reaction, [48][49][50] and hydrothermal, [51][52][53] or solvothermal methods. [54,55] To achieve a high ZT, texturing and doping have been two key approaches to enhance S 2 σ and/or reduce κ, from which the ZT values have been improved from 0.1 to ≈1.7 (p-type), although such ZT values are still much lower than their single crystal counterparts due to their relatively high κ and low S 2 σ. [52,[56][57][58][59][60] Considering the requirement of both p-type and n-type thermoelectric materials for composing the thermoelectric In this study, a record high figure of merit (ZT) of ≈1.1 at 773 K is reported in n-type highly distorted Sb-doped SnSe microplates via a facile solvothermal method. The pellets sintered from the Sb-doped SnSe microplates show a high power factor of ≈2.4 µW cm −1 K −2 and an ultralow thermal conductivity of ≈0.17 W m −1 K −1 at 773 K, leading a record high ZT. Such a high power factor is attributed to a high electron concentration of 3.94 × 10 19 cm −3 via Sb-enabled electron doping, and the ultralow thermal conductivity derives from the enhanced phonon scatter...

show abstract

Crystal structure and phase transition of thermoelectric SnSe

Cited by 82 publications

References 40 publications

High-performance SnSe thermoelectric materials: Progress and future challenge

High-performance SnSe thermoelectric materials: Progress and future challenge

High‐Performance Thermoelectric SnSe: Aqueous Synthesis, Innovations, and Challenges

Realizing High Thermoelectric Performance in n‐Type Highly Distorted Sb‐Doped SnSe Microplates via Tuning High Electron Concentration and Inducing Intensive Crystal Defects

Contact Info

Product

Resources

About