Strong enhancement of phonon scattering through nanoscale grains in lead sulfide thermoelectrics
Haijun Wu,Haijun Wu,Jesús Carrete,Zhiyun Zhang,Yongquan Qu,Xuetao Shen,Zhao Wang,Li-Dong Zhao,Jiaqing He +8 more
Reads0
Chats0
TLDR
In this article, the effect of nanograins on the reduction in lattice thermal conductivity can surpass that of nanoprecipitates at the intermediate temperature range, while simultaneously suppressing bipolar effect.Abstract:
We present nanocrystalline PbS, which was prepared using a solvothermal method followed by spark plasma sintering, as a promising thermoelectric material The effects of grains with different length scales on phonon scattering of PbS samples, and therefore on the thermal conductivity of these samples, were studied using transmission electron microscopy and theoretical calculations We found that a high density of nanoscale grain boundaries dramatically lowered the thermal conductivity by effectively scattering long-wavelength phonons The thermal conductivity at room temperature was reduced from 25 W m−1 K−1 for ingot-PbS (grain size >200 μm) to 23 W m−1 K−1 for micro-PbS (grain size >04 μm); remarkably, thermal conductivity was reduced to 085 W m−1 K−1 for nano-PbS (grain size ∼30 nm) Considering the full phonon spectrum of the material, a theoretical model based on a combination of first-principles calculations and semiempirical phonon scattering rates was proposed to explain this effective enhancement The results show that the high density of nanoscale grains could cause effective phonon scattering of almost 61% These findings shed light on developing high-performance thermoelectrics via nanograins at the intermediate temperature range Thermoelectric materials that transform waste heat generated by equipment or buildings into electricity are emerging as an important green energy technology Currently, researchers are trying to improve thermoelectric substances by embedding within them nanoscale precipitates that allow these materials to capture more heat An international team led by Jiaqing He from the South University of Science and Technology of China has now discovered a way to improve this process by systematically introducing nanoscale crystal structure defects, or ‘nanograins’, into lead sulfide (PbS) particles Their approach tripled the thermoelectric performance of this low-cost mineral from its bulk state without introducing charge-disrupting centers commonly associated with nanoscale precipitates Detailed analysis revealed that the densely packed nanograins trap heat by scattering solid-state vibrations, or phonons, while simultaneously suppressing ‘bipolar’ interactions between charge carriers that can diminish thermoelectric power We report here on the effects of grains of PbS with different length scales on thermal conductivity reduction and bipolar effect ‘suppression’ through macro-properties/microstructure analysis We found that nanograins can achieve the above goals simultaneously Combining experimental results and theoretical calculations, we found that the effect of nanograins on the reduction in lattice thermal conductivity can surpass that of nanoprecipitates Improved properties corresponding to the lowest lattice thermal conductivity in a PbQ (Q=Te, Se, S) system (05 W m K−1 at 923 K) and the highest ZT value in PbQ nanocrystalline materials were achieved by the nanograin methodread more
Citations
More filters
Journal ArticleDOI
Tuning Multiscale Microstructures to Enhance Thermoelectric Performance of n‐Type Bismuth‐Telluride‐Based Solid Solutions
Lipeng Hu,Haijun Wu,Haijun Wu,Tiejun Zhu,Chenguang Fu,Jiaqing He,Jiaqing He,Pingjun Ying,Xinbing Zhao +8 more
TL;DR: In this paper, a high figure of merit zT of 1.2 at 357 K for n-type bismuth-telluride-based thermoelectric (TE) materials through directly hot deforming the commercial zone melted (ZM) ingots is reported.
Journal ArticleDOI
Origin of the high performance in GeTe-based thermoelectric materials upon Bi2Te3 doping.
Di Wu,Li-Dong Zhao,Shiqiang Hao,Qike Jiang,Fengshan Zheng,Jeff W. Doak,Haijun Wu,Hang Chi,Yaniv Gelbstein,Ctirad Uher,Chris Wolverton,Mercouri G. Kanatzidis,Jiaqing He +12 more
TL;DR: It is shown that a remarkably high ZT of ∼1.9 can be achieved at 773 K in Ge0.87Pb0.13Te upon the introduction of 3 mol % Bi2Te3.
Journal ArticleDOI
Enhanced Thermoelectric Properties in the Counter-Doped SnTe System with Strained Endotaxial SrTe
Li-Dong Zhao,Xiao Zhang,Haijun Wu,Haijun Wu,Gangjian Tan,Yanling Pei,Yu Xiao,Cheng Chang,Di Wu,Hang Chi,Lei Zheng,Shengkai Gong,Ctirad Uher,Jiaqing He,Mercouri G. Kanatzidis +14 more
TL;DR: enhanced thermoelectric performance in SnTe, where significantly improved electrical transport properties and reduced thermal conductivity were achieved simultaneously are reported, suggesting that SnTe is a robust candidate for medium-temperature thermoelectedric applications.
Journal ArticleDOI
Principles of photothermal gas-phase heterogeneous CO2 catalysis
TL;DR: In this article, a critical appraisal of the concepts and principles underpinning the theory and practice of photothermal CO2 catalysis is provided, and the goal is to gain an appreciation of the scientific, technological, economic, and environmental challenges inevitably confronted by those pursuing the development of photiorient refineries.
Journal ArticleDOI
Synergistically optimized electrical and thermal transport properties of SnTe via alloying high-solubility MnTe
Haijun Wu,Haijun Wu,Haijun Wu,Cheng Chang,Dan Feng,Yu Xiao,Xiao Zhang,Yanling Pei,Lei Zheng,Di Wu,Shengkai Gong,Yue Chen,Jiaqing He,Mercouri G. Kanatzidis,Li-Dong Zhao +14 more
TL;DR: In this paper, the authors show that the addition of Mn (0-50%) induces multiple effects on the band structure and microstructure of SnTe, including tuning the Fermi level and promoting the convergence of the two valence bands, concurrently enhancing the Seebeck coefficient.
References
More filters
Journal ArticleDOI
Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set.
Georg Kresse,Jürgen Furthmüller +1 more
TL;DR: An efficient scheme for calculating the Kohn-Sham ground state of metallic systems using pseudopotentials and a plane-wave basis set is presented and the application of Pulay's DIIS method to the iterative diagonalization of large matrices will be discussed.
Journal ArticleDOI
Projector augmented-wave method
TL;DR: An approach for electronic structure calculations is described that generalizes both the pseudopotential method and the linear augmented-plane-wave (LAPW) method in a natural way and can be used to treat first-row and transition-metal elements with affordable effort and provides access to the full wave function.
Journal ArticleDOI
Self-interaction correction to density-functional approximations for many-electron systems
John P. Perdew,Alex Zunger +1 more
TL;DR: In this paper, the self-interaction correction (SIC) of any density functional for the ground-state energy is discussed. But the exact density functional is strictly selfinteraction-free (i.e., orbitals demonstrably do not selfinteract), but many approximations to it, including the local spin-density (LSD) approximation for exchange and correlation, are not.
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.