Intrinsically Low Lattice Thermal Conductivity and Anisotropic Thermoelectric Performance in In‐doped GeSb2Te4 Single Crystals

Layer‐structured GeSb2Te4 is a promising thermoelectric candidate, while its anisotropy of thermal and electrical transport properties is still not clear. In this study, Ge1–xInxSb2Te4 single crystals are grown by Bridgman method, and their anisotropic thermoelectric properties are systematically investigated. Lower electrical conductivity and higher Seebeck coefficient are observed in the c‐axis due to the higher effective mass in this direction. Intrinsically low lattice thermal conductivity is also observed in the c‐axis due to the weak chemical bonding and the strong lattice anharmonicity proved by density functional theory calculation. Indium doping introduces an impurity band in the bandgap of GeSb2Te4 and leads to the locally distorted density of states near the Fermi level, which contributes to enhanced Seebeck coefficient and improved power factor. Ultimately, a peak zT value of 1 at 673 K and an average zT value of 0.68 within 323–773 K are obtained in Ge0.93In0.07Sb2Te4 along the c‐axis direction, which are 54% and 79% higher than that of the pristine GeSb2Te4 single crystal, respectively. This study clarified the origin of intrinsic low lattice thermal conductivity and anisotropy transport properties in GeSb2Te4, and shed light on the performance optimization of other layered thermoelectric materials.

[1]  Terry L. Hendricks,et al.  Keynote Review of Latest Advances in Thermoelectric Generation Materials, Devices, and Technologies 2022 , 2022, Energies.

[2]  Yongxin Qin,et al.  High thermoelectric performance realized through manipulating layered phonon-electron decoupling , 2022, Science.

[3]  Xiaoyuan Zhou,et al.  Phase Modulation Enabled High Thermoelectric Performance in Polycrystalline GeSe0.75Te0.25 , 2022, Advanced Functional Materials.

[4]  G. J. Snyder,et al.  Key properties of inorganic thermoelectric materials—tables (version 1) , 2022, Journal of Physics: Energy.

[5]  Shaoting Lin,et al.  High-performance, flexible thermoelectric generator based on bulk materials , 2022 .

[6]  Huaizhou Zhao,et al.  Next-generation thermoelectric cooling modules based on high-performance Mg3(Bi,Sb)2 material , 2021, Joule.

[7]  Xiaoyuan Zhou,et al.  Realizing Enhanced Thermoelectric Performance and Hardness in Icosahedral Cu5 FeS4- x Sex with High-Density Twin Boundaries. , 2021, Small.

[8]  Xiaoyuan Zhou,et al.  Constructing n-Type Ag2Se/CNTs Composites Toward Synergistically Enhanced Thermoelectric and Mechanical Performance , 2021, Acta Materialia.

[9]  M. Kanatzidis,et al.  High-performance thermoelectrics and challenges for practical devices , 2021, Nature Materials.

[10]  Xiaoyuan Zhou,et al.  Realizing Cd and Ag codoping in p-type Mg3Sb2 toward high thermoelectric performance , 2021, Journal of Magnesium and Alloys.

[11]  Xiaoyuan Zhou,et al.  Melt-spun Sn1−−Sb Mn Te with unique multiscale microstructures approaching exceptional average thermoelectric zT , 2021 .

[12]  Xiaoyuan Zhou,et al.  Atomic‐Scale Visualization and Quantification of Configurational Entropy in Relation to Thermal Conductivity: A Proof‐of‐Principle Study in t‐GeSb2Te4 , 2021, Advanced science.

[13]  S. Pennycook,et al.  Coherent Sb/CuTe Core/Shell Nanostructure with Large Strain Contrast Boosting the Thermoelectric Performance of n‐Type PbTe , 2020, Advanced Functional Materials.

[14]  Zihang Liu,et al.  High Power Factor and Enhanced Thermoelectric Performance in Sc and Bi Codoped GeTe: Insights into the Hidden Role of Rhombohedral Distortion Degree , 2020, Advanced Energy Materials.

[15]  Y. S. Zhang,et al.  Realizing high thermoelectricity in polycrystalline tin sulfide via manipulating fermi surface anisotropy and phonon dispersion , 2020 .

[16]  Jiong Yang,et al.  Anion-site-modulated thermoelectric properties in Ge2Sb2Te5-based compounds , 2020, Rare Metals.

[17]  Xiaoyuan Zhou,et al.  High Thermoelectric Performance in Sulfide‐Type Argyrodites Compound Ag8Sn(S1−xSex)6 Enabled by Ultralow Lattice Thermal Conductivity and Extended Cubic Phase Regime , 2020, Advanced Functional Materials.

[18]  J. Shuai,et al.  Manipulating the Ge Vacancies and Ge Precipitates through Cr Doping for Realizing the High-Performance GeTe Thermoelectric Material. , 2020, Small.

[19]  Xinxin Yang,et al.  Effective Mass Enhancement and Thermal Conductivity Reduction for Improving the Thermoelectric Properties of Pseudo‐Binary Ge2Sb2Te5 , 2019, Annalen der Physik.

[20]  Xiaolong Du,et al.  Enhanced Thermoelectric Performance and Service Stability of Cu2Se Via Tailoring Chemical Compositions at Multiple Atomic Positions , 2019, Advanced Functional Materials.

[21]  Haijun Wu,et al.  High thermoelectric performance in low-cost SnS0.91Se0.09 crystals , 2019, Science.

[22]  Jiong Yang,et al.  Largely enhanced Seebeck coefficient and thermoelectric performance by the distortion of electronic density of states in Ge2Sb2Te5. , 2019, ACS applied materials & interfaces.

[23]  Yue Chen,et al.  Dilute Cu2Te-alloying enables extraordinary performance of r-GeTe thermoelectrics , 2019, Materials Today Physics.

[24]  Lidong Chen,et al.  Quasi-two-dimensional GeSbTe compounds as promising thermoelectric materials with anisotropic transport properties , 2019, Applied Physics Letters.

[25]  Y. Wang,et al.  Strong Phonon-Phonon Interactions Securing Extraordinary Thermoelectric Ge1- xSb xTe with Zn-Alloying-Induced Band Alignment. , 2019, Journal of the American Chemical Society.

[26]  Gang Chen,et al.  Routes for high-performance thermoelectric materials , 2018, Materials Today.

[27]  C. Uher,et al.  Sodium‐Doped Tin Sulfide Single Crystal: A Nontoxic Earth‐Abundant Material with High Thermoelectric Performance , 2018 .

[28]  Yue Chen,et al.  3D charge and 2D phonon transports leading to high out-of-plane ZT in n-type SnSe crystals , 2018, Science.

[29]  M. Dargusch,et al.  Realizing zT of 2.3 in Ge1−x−ySbxInyTe via Reducing the Phase‐Transition Temperature and Introducing Resonant Energy Doping , 2018, Advanced materials.

[30]  M. Kanatzidis,et al.  Rhombohedral to Cubic Conversion of GeTe via MnTe Alloying Leads to Ultralow Thermal Conductivity, Electronic Band Convergence, and High Thermoelectric Performance. , 2018, Journal of the American Chemical Society.

[31]  C. Uher,et al.  Intrinsically low thermal conductivity from a quasi-one-dimensional crystal structure and enhanced electrical conductivity network via Pb doping in SbCrSe3 , 2017 .

[32]  Heng Wang,et al.  Ultrahigh power factor and thermoelectric performance in hole-doped single-crystal SnSe , 2016, Science.

[33]  A. Pöppl,et al.  Doping GeSb2Te4 with Cr3+: Structure and Temperature-Dependent Physical Properties† , 2015 .

[34]  Jihui Yang,et al.  Conductivity-limiting bipolar thermal conductivity in semiconductors , 2015, Scientific Reports.

[35]  T. Seetawan,et al.  Electronic Structure of Ge-Sb-Te System Calculated by DV-Xα Method , 2014 .

[36]  M. Kanatzidis,et al.  Ultralow thermal conductivity and high thermoelectric figure of merit in SnSe crystals , 2014, Nature.

[37]  B. Liao,et al.  High thermoelectric performance by resonant dopant indium in nanostructured SnTe , 2013, Proceedings of the National Academy of Sciences.

[38]  V. Ozoliņš,et al.  High Performance Thermoelectricity in Earth‐Abundant Compounds Based on Natural Mineral Tetrahedrites , 2013 .

[39]  Lei Yang,et al.  Nanostructured thermoelectric materials: current research and future challenge , 2012 .

[40]  M. Kanatzidis,et al.  High-performance bulk thermoelectrics with all-scale hierarchical architectures , 2012, Nature.

[41]  Volker L. Deringer,et al.  Crystal orbital Hamilton population (COHP) analysis as projected from plane-wave basis sets. , 2011, The journal of physical chemistry. A.

[42]  Heng Wang,et al.  Convergence of electronic bands for high performance bulk thermoelectrics , 2011, Nature.

[43]  G. Kotliar,et al.  Peierls distortion as a route to high thermoelectric performance in In4Se3-δ crystals , 2009, Nature.

[44]  G. J. Snyder,et al.  Enhancement of Thermoelectric Efficiency in PbTe by Distortion of the Electronic Density of States , 2008, Science.

[45]  G. J. Snyder,et al.  Complex thermoelectric materials. , 2008, Nature materials.

[46]  R. Ahuja,et al.  Structure of the Ge-Sb-Te phase-change materials studied by theory and experiment , 2007 .

[47]  S. Dong,et al.  Microstructures and thermoelectric properties of GeSbTe based layered compounds , 2007 .

[48]  G. Kresse,et al.  Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set , 1996 .