Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 21
·5562-5571
·
IF 7.779
Fudong Zhang,Xia Qi,Mingkai He,Fengshan Zheng,Lei Jin,Zhanhui Peng,Xiaolian Chao,Zupei Yang,Di Wu
Previous studies have revealed that both Bi doping and Bi2Te3 alloying are successful strategies to optimize the thermoelectric performance of SnTe; however, detailed and thorough investigations on exactly how they differ in modulating the band structure and microstructure were seldom given. Through a systematic comparison between Bi-doped and Bi2Te3-alloyed SnTe, we find in this work that despite the fact that they both contribute to the valence band convergence of SnTe, Bi2Te3 alloying induces little effect on the hole concentration unlike the typical n-type feature of Bi-doping; moreover, Bi2Te3 alloying tends to produce dense dislocation arrays at micron-scale grain boundaries which differs significantly from the substitutional point defect character upon Bi-doping. It was then found that Bi2Te3 alloying exhibits a relatively higher quality factor (B ∼ μw/κlat) at higher temperatures than Bi-doping. Subsequent Ge-doping in Bi2Te3-alloyed samples results in further valence band convergence and hole concentration optimization and eventually results in a maximum figure of merit ZT of 1.4 at 873 K in the composition of (Sn0.88Ge0.12Te)0.97-(BiTe1.5)0.03.
研究领域:
材料科学
·
热电材料
✓ 已验证
DOI
高影响因子
Nature Communications
·
2019
·Vol. 10
·期 1
·1-9
·
IF 11.878
Ren Guang-Kun,Wang Shanyu,Zhou Zhifang,Li Xin,Yang Jiong,Zhang Wenqing,Lin Yuan-Hua,Yang Jihui,Nan Ce-Wen
BiCuSeO oxyselenides are promising thermoelectric materials, yet further thermoelectric figure of merit ZT improvement is largely limited by the inferior electrical transport properties. The established literature on these materials shows only one power factor maximum upon carrier concentration optimization, which is typical for most thermoelectric semiconductors. Surprisingly, we found three power factor maxima when doping Bi with Pb. Based on our first-principles calculations, numerical modeling, and experimental investigation, we attribute the three maxima to the Fermi energy optimization, band convergence, and compositing effect due to in situ formed PbSe precipitates. Consequently, three ZT peaks of 0.9, 1.1, and 1.3 at 873 K are achieved for 4, 10, and 14 at.% Pb-doped samples, respectively, revealing the significance of complex electronic structure and multiple roles of Pb in BiCuSeO. The results establish an accurate band structure characterization for BiCuSeO and identify the role of band convergence and nanoprecipitation as the driving mechanism for high ZT.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
Nanoscale
·
2020
·Vol. 12
·期 10
·5857-5865
·
IF 6.895
Wenqi Lu,Tiantian He,Shuang Li,Xinru Zuo,Yao Zheng,Xunuo Lou,Jian Zhang,Di Li,Jizi Liu,Guodong Tang
SnTe is considered as a promising alternative to the conventional high-performance thermoelectric material PbTe, which inspired the thermoelectric community for a while. Here, we design a green, facile and low-energy-intensity hydrothermal route without involving any toxic or unstable chemicals to fabricate SnTe-based thermoelectric materials. Ultralow lattice thermal conductivity and enhanced thermoelectric performance are achieved via the combination of band engineering and nanostructuring. Enhanced Seebeck coefficient and power factor are induced by converging the band structure and creating resonant levels due to Pb and In doping. More importantly, due to the reduced grain sizes, nanoparticles, and dual-atom point defect scattering, ultralow lattice thermal conductivity was obtained in the bulk samples fabricated by the hydrothermal route. Benefiting from the enhanced power factor and significantly reduced thermal conductivity, the peak ZT is enhanced to ∼0.7 in In/Pb codoped SnTe, a 60% improvement over pure SnTe.
研究领域:
材料科学
·
能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2021
·
IF 8.067
Ximeng Dong,Wenlin Cui,Wei-Di Liu,Shuqi Zheng,Lei Gao,Luo Yue,Yue Wu,Boyi Wang,Zipei Zhang,Liqiang Chen,Zhi-Gang Chen
As an eco-friendly thermoelectric material, SnTe has attracted extensive attention. In this study, we use a stepwise strategy to enhance the thermoelectric performance of SnTe. Firstly, AgCl is doped into SnTe to realize band convergence and enlarge the band gap of AgCl-doped SnTe. AgCl-doping also induces dense point defects , strengthens the phonon scattering, and reduces the lattice thermal conductivity . Secondly, Sb is alloyed into AgCl-doped SnTe to further optimize the carrier concentration and simultaneously reduce the lattice thermal conductivity , leading to improved thermoelectric dimensionless figure of merit, ZT . Finally, (Sn 0.81 Sb 0.19 Te) 0.93 (AgCl) 0.07 has approached the ZT value as high as ∼0.87 at 773 K, which is 272 % higher than that of pristine SnTe. This study indicates that stepwise AgCl-doping and Sb-alloying can significantly improve thermoelectric performance of SnTe due to synergistic band engineering, carrier concentration optimization and defect engineering.
研究领域:
材料科学
·
热电学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-8
·
IF 14.919
Jiang Binbin,Yu Yong,Chen Hongyi,Cui Juan,Liu Xixi,Xie Lin,He Jiaqing
We demonstrate that the thermoelectric properties of p-type chalcogenides can be effectively improved by band convergence and hierarchical structure based on a high-entropy-stabilized matrix. The band convergence is due to the decreased light and heavy band energy offsets by alloying Cd for an enhanced Seebeck coefficient and electric transport property. Moreover, the hierarchical structure manipulated by entropy engineering introduces all-scale scattering sources for heat-carrying phonons resulting in a very low lattice thermal conductivity. Consequently, a peak zT of 2.0 at 900 K for p-type chalcogenides and a high experimental conversion efficiency of 12% at Δ T = 506 K for the fabricated segmented modules are achieved. This work provides an entropy strategy to form all-scale hierarchical structures employing high-entropy-stabilized matrix. This work will promote real applications of low-cost thermoelectric materials.
研究领域:
材料科学
·
热电学
·
物理学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Shaoqing Lu,Zhengyi Zhu,Weite Meng,Jian Wang,Lulu Huang,Mengyao Li,Aziz Genç,Siqi Huo,Khak Ho Lim,Andreu Cabot,Yucheng Wu,Yu Zhang,Min Hong,Jian Yan,Yu Liu
Thermoelectric (TE) materials, capable of directly converting heat into electricity, offer a promising route for sustainable energy recovery. However, practical deployment is limited by the difficulty in simultaneously optimizing electrical and thermal transport properties. In this study, a synergistic microstructure-composition co-design strategy for enhancing the performance of PbTe-based TEs via Na 2 S-assisted solid-state synthesis is presented. The thermal decomposition of Na 2 S not only introduces hierarchical porosity but also facilitates initial Na doping, enabling the concurrent optimization of phonon scattering, carrier concentration, and band convergence. The optimized composition, Pb 0.97 Na 0.03 Te-1.0%Na 2 S, exhibits refined grains, dispersed Na 2 Te nanoprecipitates, and a high density of dislocations, leading to ultralow lattice thermal conductivity (≈0.50 W m −1 K −1 at 750 K) while preserving excellent electrical transport. A peak TE figure of merit zT ≈2.2 at 823 K and a high average zT ≈1.9 across 623–823 K are achieved. To validate the device-level applicability, single-leg TE modules are fabricated, achieving a high conversion efficiency of 13.4% at Δ T = 395 K, which is among the best reported for a PbTe-based system. Furthermore, a unicouple module integrated with n-type skutterudite reaches a record power density of 2.2 W cm −2 at Δ T = 375 K. This study highlights a scalable pathway for advancing mid-temperature TE materials and devices through structural and compositional engineering.
研究领域:
材料科学
·
热电学
·
固态化学
·
能量转换
·
纳米材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）