Journal ArticleDOI
Structural stability enables high thermoelectric performance in room temperature Ag2Se
Reads0
Chats0
TLDR
In this paper, the authors reveal the coexistence of a metastable and the main orthorhombic crystal structure in stoichiometric Ag2Se, and the formation of the metastable structure was found to be detrimental to the transport properties.Abstract:
Ag2Se is considered as an attractive candidate for use in room-temperature thermoelectric applications owing to its unique transport properties, such as glass-like thermal conductivity and good electrical conductivity. However, understanding the correlation between composition (Ag/Se ratio), defect structure, and transport properties is an important prerequisite to optimize its figure of merit (ZT). Using in-depth microscopic analysis, this study reveals the coexistence of a metastable and the main orthorhombic crystal structure in stoichiometric Ag2Se. The formation of the metastable structure was found to be detrimental to the transport properties of bulk Ag2Se. We were able to successfully inhibit its formation and stabilize the main orthorhombic structure via small anion (Se and S) excess. The compositions Ag2SeChy (y ≤ 0.01; Ch = Se, S) yielded 40–70% rise in carrier mobility with a value of 2510 cm2 V−1 s−1 at 300 K and extremely low lattice-thermal-conductivity (0.2–0.1 W m−1 K−1 over 300–375 K). This combination of transport properties yielded a room-temperature power factor of 3.2 mW m−1 K−2 and a nearly flat ZT value of ∼1.0 over the 300–375 K temperature range. Additionally, a record-high conversion efficiency (ηmax) of 3.7% was theoretically obtained for single-leg Ag2Se for a small temperature gradient of ∼80 K.read more
Citations
More filters
Journal ArticleDOI
Na Doping in PbTe: Solubility, Band Convergence, Phase Boundary Mapping, and Thermoelectric Properties
Priyanka Jood,James P. Male,Shashwat Anand,Yoshitaka Matsushita,Yoshiki Takagiwa,Mercouri G. Kanatzidis,G. Jeffrey Snyder,Michihiro Ohta +7 more
TL;DR: A phase diagram approach is applied to explain the origins of increased solubility from excess Na doping and offer strategies for repeatable synthesis of high zT Na-doped materials.
Journal ArticleDOI
Hierarchical structures advance thermoelectric properties of porous n-type β-Ag2Se
Jie Chen,Qiang Sun,Deyu Bao,Taoyi Liu,Wei-Di Liu,Can Liu,Jun Tang,Dali Zhou,Lei Yang,Zhigang Chen +9 more
TL;DR: An energy- and time-efficient wet mechanical alloying and spark plasma sintering method is developed to prepare porous β-Ag2Se with hierarchical structures including high- density pores, a metastable phase, nanosized grains, semi-coherent grain boundaries, high-density dislocations, and localized strains, suggesting that β- Ag2Se can be a competitive candidate for room-temperature thermoelectric applications.
Journal ArticleDOI
High performance wearable thermoelectric generators using Ag2Se films with large carrier mobility
Shuaihang Hou,Yijie Liu,Li Yin,Chen Chen,Zuoxu Wu,Jian Wang,Yi Luo,Wenhua Xue,Xingjun Liu,Qian Zhang,Feng Cao +10 more
TL;DR: In this paper, a 4-leg flexible thermoelectric generator composed of the Ag1.8Se (x = 1.6, 1.8, 2.0, and 2.2) films was successfully deposited on the polyimide substrate by thermal evaporation.
Journal ArticleDOI
Biomimetic Approach to Facilitate the High Filler Content in Free-Standing and Flexible Thermoelectric Polymer Composite Films Based on PVDF and Ag2Se Nanowires.
TL;DR: This work carves a path to fabricate high-performance free-standing flexible n-type TE composite films as well as other functional polymer composites requiring high inorganic filler loading.
Journal ArticleDOI
Investigation on Low-Temperature Thermoelectric Properties of Ag2Se Polycrystal Fabricated by Using Zone-Melting Method.
Min Jin,Jiasheng Liang,Pengfei Qiu,Hui Huang,Zhongmou Yue,Lina Zhou,Rongbin Li,Lidong Chen,Xun Shi +8 more
TL;DR: In this paper, the electrical and thermal transport properties of zone-melted Ag2Se were systematically investigated and compared with other typical low-temperature thermoelectric materials, such as Mg3Bi2, Bi2Te3, and BiSb.
References
More filters
Journal ArticleDOI
Complex thermoelectric materials.
TL;DR: A new era of complex thermoelectric materials is approaching because of modern synthesis and characterization techniques, particularly for nanoscale materials, and the strategies used to improve the thermopower and reduce the thermal conductivity are reviewed.
Journal ArticleDOI
Cooling, heating, generating power, and recovering waste heat with thermoelectric systems.
TL;DR: Thermoelectric materials are solid-state energy converters whose combination of thermal, electrical, and semiconductor properties allows them to be used to convert waste heat into electricity or electrical power directly into cooling and heating.
Journal ArticleDOI
High-Thermoelectric Performance of Nanostructured Bismuth Antimony Telluride Bulk Alloys
Bed Poudel,Qing Hao,Yi Ma,Yucheng Lan,Austin J. Minnich,Bo Yu,Xiao Yan,Dezhi Wang,Andrew Muto,Daryoosh Vashaee,Xiaoyuan Chen,Jun-Ming Liu,Mildred S. Dresselhaus,Gang Chen,Zhifeng Ren +14 more
TL;DR: Electrical transport measurements, coupled with microstructure studies and modeling, show that the ZT improvement is the result of low thermal conductivity caused by the increased phonon scattering by grain boundaries and defects, which makes these materials useful for cooling and power generation.
Journal Article
High Thermoelectric Performance of Nanostructured Bismuth Antimony Telluride Bulk Alloys.
Bed Poudel,Qing Hao,Yi Ma,Austin J. Minnich,Andrew Muto,Yucheng Lan,Bo Yu,Xiao Yan,Dezhi Wang,Daryoosh Vashaee,X.Y. Chen,Dresselhaus,Gang Chen,Zhifeng Ren +13 more
BookDOI
CRC Handbook of Thermoelectrics
TL;DR: In this article, Rowe et al. proposed a method for reducing the thermal conductivity of a thermoelectric generator by reducing the carrier concentration of the generator, which was shown to improve the generator's performance.