Minimum Lattice Thermal Conductivity Research Articles

Vacancy Suppression and Resonant Level Rendering Extraordinary Power Factor in Sn0.99In0.01Te/Tourmaline Composite.

SnTe, as a potential medium-temperature thermoelectric material, reaches a maximum power factor (PF)usually above 750K, which is not conducive to continuous high-power output in practical applications. In this study, PF is maintained at high values between 18.5 and 25µWcm-1K-2 for Sn0.99In0.01Te-xwt% tourmaline samples within the temperature range of 323 to 873K, driving the highest PFeng of 1.2Wm-1K-1 and PFave of 22.5µWcm-1K-2, over 2.5 times that of pristine SnTe. Such an extraordinary PF is attributed to the synergy of resonant levels and Sn vacancy suppression. Specifically, the Seebeck coefficient increases dramatically, reaching 88µVK-1 at room temperature. Meanwhile, by Sn vacancy suppression, carrier concentration, and mobility are optimized to ≈1019cm-3 and 740cm2V-1s-1, respectively. With the tourmaline compositing, Sn vacancies are further suppressed and the thermal conductivity simultaneously decreases, with the minimum lattice thermal conductivity of 0.9W m-1 K-1. Finally, the zT value ≈0.8 is obtained in the Sn0.99In0.01Te sample. The peak of the power output density reaches 0.89W cm-2 at a temperature difference of 600K. Such SnTe alloys with high and "temperature-independent" PF will offer an option for realizing high output power in thermoelectric devices.

Preparation of High-Performance Mn-Doped SnTe Materials at High Pressure and High Temperature.

SnTe is an environmentally friendly medium-temperature thermoelectric material, but its inherent low power factor (PF) and high lattice thermal conductivity severely limit its application. In this study, based on the fact that Mn doping can induce band convergence, the high-pressure and high-temperature (HPHT) synthesis method was used to optimize the sample preparation and shorten the synthesis cycle to 30 min. The results show that the Sn0.93Mn0.10Te sample achieves the maximum PF value of 34.00 μW cm-1 K-2 at 775 K and PFave value of 21.36 μW cm-1 K-2 between 300-875 K. Microstructure analysis shows that the high-pressure synthesis method introduces abundant grain boundaries, various grain sizes, multiple defects, and pore structures into the sample. These microscopic crystal structures can effectively scatter phonons and lower the lattice thermal conductivity. The modification of these micromorphologies results in the Sn0.92Mn0.11Te sample attaining a minimum lattice thermal conductivity of 0.45 W m-1 K-1 at 625 K. The thermoelectric figure of merit (zT) of sample Sn0.92Mn0.11Te reaches a maximum value of 1.1 at 775 K, and the zTave reaches 0.63 in the range of 300-875 K. This study indicates that the synergistic effect of Mn element doping and microstructure modification can effectively optimize the thermoelectric transport performance of SnTe materials.

Study of the Lattice Thermal Conductivity of Janus In2Ge2S6 and In2Ge2S3Se3 Bilayers

In this paper, we investigate the lattice thermal conductivity of Janus In2Ge2S6 and In2Ge2S3Se3 bilayers by solving the phonon Boltzmann transport equation using first-principles calculations. We found that this is mainly due to the fact that the frequencies at which larger gaps appear in the intermediate and high frequency optical branches of In2Ge2S3Se3 are smaller than those of In2Ge2S6, which shifts the phonon dispersion curve of In2Ge2S3Se3 downward, which makes the overall phonon group velocity of In2Ge2S3Se3 material smaller than that of In2Ge2Se6 material, and also due to the fact that In2Ge2S3Se3 soft bending in the finite layer thickness coupling and the tight connection of the in-plane acoustic modes, resulting in increased phonon-phonon scattering processes, shorter phonon relaxation times, and larger Grüneisen parameters indicating a stronger anharmonic In2Ge2S3Se3 structure, all these factors combined lead to a lattice thermal conductivity of In2Ge2S3Se3 smaller than the lattice thermal conductivity of In2Ge2S6. At a temperature of 1000 K, the In2Ge2S3Se3 structure has a minimum lattice thermal conductivity of about 0.22 W/mK, and In2Ge2S6 has a minimum lattice thermal conductivity of about 0.4 W/mK. Our results suggest that Janus In2Ge2S6 and In2Ge2S3Se3 bilayers are potential for future thermal management of nanoelectronic devices and thermoelectric devices. two-dimensional materials.

First-principles study on the lattice thermal conductivity of Janus In2Ge2Te3Se3 and In2Ge2Se6 bilayers：Candidate materials for thermoelectric devices in high-temperature conditions

Improvement of existing material properties is necessary for high-efficiency thermoelectric power conversion, but novel thermoelectric materials must also be predicted and synthesized. Here we solve the phonon Boltzmann transport equation using first-principles computations to examine the lattice thermal conductivity of Janus In2Ge2Te3Se3 and In2Ge2Se6 bilayers. Results show that the frequencies at which larger gaps appear in the intermediate and high-frequency optical branches of In2Ge2Te3Se3 are lower than those of In2Ge2Se6. As a result, the phonon dispersion curve of In2Ge2Te3Se3 shifts downward. Since Te atoms are heavier than Se atoms, compared to In2Ge2Se6, In2Ge2Te3Se3 has a lower overall phonon group velocity. Furthermore, the tight coupling of the in-plane acoustic modes and the soft bending of In2Ge2Te3Se3 in the finite layer thickness coupling result in an increase in the phonon-phonon scattering, a reduction in the phonon relaxation time, and a larger Grüneisen parameter, indicating that In2Ge2Te3Se3 is more anharmonic. At a temperature of 1000 K, the sum of all these parameters results in a minimum lattice thermal conductivity of 0.05 W/mK for In2Ge2Te3Se3 and 0.24 W/mK for In2Ge2Se6. This study sheds light on the Janus In2Ge2Te3Se3 and In2Ge2Se6 bilayer thermal transport capabilities, it may open the door for achieving thermal conductivity control in applications such as thermal management and thermoelectric devices.

Enhancing the Thermoelectric Properties via Modulation of Defects in P‐Type MNiSn‐Based (M = Hf, Zr, Ti) Half‐Heusler Materials

AbstractThe thermoelectric figure‐of‐merit (zT) of p‐type MNiSn (M = Ti, Zr, or Hf) half‐Heusler compounds is lower than their n‐type counterparts due to the presence of a donor in‐gap state caused by Ni occupying tetrahedral interstitials. While ZrNiSn and TiNiSn, have been extensively studied, HfNiSn remains unexplored. Herein, this study reports an improved thermoelectric property in p‐type HfNi1−xCoxSn. By doping 5 at% Co at the Ni sites, the Seebeck coefficient becomes reaching a peak value exceeding 200 µV K−1 that breaks the record of previous reports. A maximum power factor of ≈2.2 mW m−1 K−2 at 973 K is achieved by optimizing the carrier concentration. The enhanced p‐type transport is ascribed to the reduced content of Ni defects, supported by first principle calculations and diffraction pattern refinement. Concomitantly, Co doping also softens the lattice and scatters phonons, resulting in a minimum lattice thermal conductivity of ≈1.8 W m−1 K−1. This leads to a peak zT of 0.55 at 973 K is realized, surpassing the best performing p‐type MNiSn by 100%. This approach offers a new method to manipulate the intrinsic atomic disorder in half‐Heusler materials, facilitating further optimization of their electronic and thermal properties.

A novel valence-balanced double half-Heusler Ti2Zr2Hf2NbVFe5Ni3Sb8 alloy by high entropy engineering

The lattice thermal conductivity of stable 18-electron Ti2FeNiSb2 compound is remarkably lower than that of the traditional ternary half-Heusler alloy, and it is considered a promising thermoelectric material. Owing to the distinctive performance of high entropy alloys, we designed a novel valence-balanced double half-Heusler Ti2Zr2Hf2NbVFe5Ni3Sb8 alloy with high entropy sublattice. The experimental results showed that enhanced electrical transport properties and reduced thermal conductivity of the alloy were achieved. The thermal conductivity at room temperature was two fifths of that of reported Ti2FeNiSb2 and the maximum power factor improved three times. The ultralow theoretical minimum lattice thermal conductivity was estimated to be less than 0.2 W m−1K−1, showing the possibility for further reduction. Phonon spectrum calculation showed that the high entropy strategy was valid for scattering phonons and limiting lattice thermal conductivity. A peak ZT ∼0.027 at 823 K was achieved, which is almost five times that of the Ti2FeNiSb2. This work demonstrates the effectiveness of the high entropy strategy in double half-Heusler compounds and the potential of the new concept of HE-DHH compounds as high-performance thermoelectric materials.

Thermoelectric properties of Tsai-type Au–(Al, Ga, In)–Gd approximants

In this work, the thermoelectric properties of Tsai-type Au–(Al, Ga, In)–Gd approximant crystals (ACs) are investigated over a temperature range of 300–773 K. The changes in lattice constants and effective speed of sound suggest a weaker chemical bonding caused by a replacement of Al by heavier Ga or In atoms. Based on electrical conductivity measurements, Au–Al–Gd shows the deepest pseudogap in spectrum conductivity at the Fermi level, followed by Au–Ga–Gd and Au–In–Gd ACs. The lattice thermal conductivity at 300 K is as low as 0.71–0.81 W m−1 K−1 and asymptotically approaches a minimum lattice thermal conductivity of 0.52–0.59 W m−1 K−1 as calculated using the Cahill model. As a result, the highest power factor and dimensionless figure of merit reach ∼120 µW m−1 K−2 and ∼0.008 at ∼700 K for the Au–In–Gd system. Our systematic approach of weakening the chemical bonding nature by heavy atom substitution promises a better thermoelectric performance of Tsai-type ACs.

A unified understanding of minimum lattice thermal conductivity

We propose a first-principles model of minimum lattice thermal conductivity ([Formula: see text]) based on a unified theoretical treatment of thermal transport in crystals and glasses. We apply this model to thousands of inorganic compounds and find a universal behavior of [Formula: see text] in crystals in the high-temperature limit: The isotropically averaged [Formula: see text] is independent of structural complexity and bounded within a range from ∼0.1 to ∼2.6 W/(m K), in striking contrast to the conventional phonon gas model which predicts no lower bound. We unveil the underlying physics by showing that for a given parent compound, [Formula: see text] is bounded from below by a value that is approximately insensitive to disorder, but the relative importance of different heat transport channels (phonon gas versus diffuson) depends strongly on the degree of disorder. Moreover, we propose that the diffuson-dominated [Formula: see text] in complex and disordered compounds might be effectively approximated by the phonon gas model for an ordered compound by averaging out disorder and applying phonon unfolding. With these insights, we further bridge the knowledge gap between our model and the well-known Cahill-Watson-Pohl (CWP) model, rationalizing the successes and limitations of the CWP model in the absence of heat transfer mediated by diffusons. Finally, we construct graph network and random forest machine learning models to extend our predictions to all compounds within the Inorganic Crystal Structure Database (ICSD), which were validated against thermoelectric materials possessing experimentally measured ultralow κL. Our work offers a unified understanding of [Formula: see text], which can guide the rational engineering of materials to achieve [Formula: see text].

Boosting Thermoelectric Performance in Epitaxial GeTe Film/Si by Domain Engineering and Point Defect Control

This study demonstrates a simultaneous realization of ultralow thermal conductivity and high thermoelectric power factor in epitaxial GeTe thin films/Si substrates by a combination of the interface introduction by domain engineering and the suppression of Ge vacancy generation by point defect control. We formed epitaxial Te-poor GeTe thin films having low-angle grain boundaries with a misorientation angle close to 0° or twin interfaces with a misorientation angle close to 180°. The control of interfaces and point defects gave rise to ultralow lattice thermal conductivity of ∼0.7 ± 0.2 W m-1 K-1. This value was the same in the order of magnitude as the theoretical minimum lattice thermal conductivity of ∼0.5 W m-1 K-1 calculated by the Cahill-Pohl model. At the same time, the GeTe thin films exhibited a high thermoelectric power factor because of the suppression of Ge vacancy generation and a small contribution of grain boundary carrier scattering. The outstanding combined technique of domain engineering and point defect control can be a great approach for developing high-performance thermoelectric films.

From phonons to the thermal properties of complex thermoelectric crystals: The case of type-I clathrates

Exploiting the structural complexity of crystals at the scale of their unit cell is a well-established strategy in the search for efficient materials for energy conversion, which aims at disentangling and separately engineering heat and charge transport. This route has resulted in the discovery of clathrates with exceptionally low lattice thermal conductivity but essentially unaffected and tunable electronic properties. Although their thermal conductivity behaves similarly to the one of glasses, its origin is fundamentally different. Indeed, phonons with long lifetime were observed over the whole Brillouin zone, thus excluding an interpretation in terms of a reduced mean free path. However, the energy–momentum phase space which contains these heat carrying phonons is capped by a dense spectrum of diffusive modes. The thermal properties of clathrates can therefore be split in two parts: a narrow low energy regime that contains propagative modes which dominate the thermal transport, and a broad high energy range consisting of diffusive modes that dominate the heat capacity. Based on this understanding, a simple phenomenological model, based on a basic description in terms of Debye and Einstein modes, is derived that allows for a meaningful interpretation of experimental data, by providing a connection to the underlying microscopic origin. Finally, the criteria for determining the minimum lattice thermal conductivity are redefined and strategies for decreasing the lattice conductivity are proposed.

Exploration of the structural, vibrational, electronic, mechanical and thermal properties of Ru4Al3B2 and Ru9Al3B8: a DFT study.

The structural, dynamical, electro-optical, mechanical, and thermal characteristics of the newly synthesized intermetallic compounds Ru4Al3B2 and Ru9Al3B8 have been studied under ambient and elevated pressure through density functional theory (DFT). The obtained lattice parameters of the compounds are consistent with the experimental values. The metallic character of these compounds is established by the band structure and density of states (DOS). The electronic charge density distribution and bond analysis imply that Ru4Al3B2 and Ru9Al3B8 have mainly both ionic and covalent bonding. The non-negative phonon dispersion frequency of the compounds reaffirms their dynamical stability. Both compounds are tough as well as have high melting points, and hence, can be applied in harsh conditions. Mechanical properties are significantly improved under pressure. Thermal barrier coating (TBC) is a possible field of application for both compounds. The different thermal properties such as the Debye temperature (ΘD), Grüneisen parameter (γ), melting temperature (Tm), minimum thermal conductivity (Kmin) and lattice thermal conductivity (κph) of these compounds have been studied to figure out the suitable application areas in thermally demanding situations. The pressure and temperature dependent bulk modulus (B) and other thermodynamic properties have also been analyzed, which suggested that the present compounds are strong candidates for device applications at high temperature and pressure. Owing to their high optical absorptivity and reflectivity in the UV region, they are also candidates for UV-based applications. Furthermore, they also have applicability in the fields of electronics, aviation, energy storage, and supercapacitor devices for their superior electronic, thermal and mechanical properties.

Approaching the minimum lattice thermal conductivity in TiCoSb half-Heusler alloys by intensified point-defect phonon scattering

Enhanced point defect phonons scattering through huge isovalent substitution substantially reduces the lattice thermal conductivity of half-Heusler alloys.

Thermoelectric properties and the effect of biaxial strain and external electric fields on the electronics of novel 2D Lace-like O-Pd2Q3 (Q= S, Se) monolayers

Inspired by the experimental synthesis of the novel 2D O-Pd2Se3 monolayer, we performed density functional theory calculations to reveal detailed investigations of the electronics, and thermal properties of 2D O-Pd2Q3 (Q= S, Se) monolayers. The O-Pd2S3 and Pd2Se3 are semiconductors with indirect band gaps of 0.43 eV and 0.33 eV, respectively. Through strain engineering, the bulk modulus B (N/m) and young's modulus Y (N/m) are also determined to acquire a deep understanding of the elasticity of the monolayers. We find that the bandgaps tend to increase with increasing tensile biaxial strain (+ε%), and decrease with increasing compressive biaxial strain (-ε%). In particular, the O-Pd2Se3 monolayer starts to manifest a metallic feature at -5%. More importantly, we note that at room temperature, and under biaxial strain, O-Pd2S3 (O-Pd2Se3) has a high electron (hole) carrier mobility up to ∼ 766 cm2 V−1 s−1 (∼ 106 cm2 V−1 s−1). We have also tuned the band gaps of the monolayers via the application of an external electric field, along the z-direction. We find that, in the [-2.5, +2.5] V/Å range, such external electric fields reduce the bandgaps in both monolayers, transforming Pd2Se3 into a metal at a strength of ± 2.5 V/Å. Additionally, we have perceived that the thermoelectric (TE) properties of these materials exhibit an anisotropic behavior at ambient and higher temperatures. At 300K, the O- Pd2Se3 monolayers show a large thermal electronic conductivity and a power factor of about 18 (16) times that of O-Pd2S3 along the x (y) directions. At temperatures higher than 600K, these properties become more dominant in O-Pd2S3. The acquired power factor of O-Pd2S3 (O-Pd2Se3) is much higher than that of the 1T phase of PdS2 (1T PdSe2 and penta-PdSe2). By just knowing the group velocities of the three acoustical modes, we were able to determine the minimum lattice thermal conductivity, which is 0.207 W/(m.K) for both systems. If properly exploited, these characteristics make the O-Pd2Q3 monolayers excellent candidates for the fabrication of novel ultrathin electronic and TE nanodevices at ambient and higher temperatures.

First-principles investigation of mechanical properties, elastic anisotropy, and ultralow lattice thermal conductivities of ductile Mg–Bi alloys

The crystal structures, mechanical properties, anisotropic properties, and lattice thermal conductivities of Mg–Bi alloys have been investigated by particle swarm optimization structure prediction method and first-principles calculations. Apart from the well-known stoichiometry of Mg3Bi2, the novel stable stoichiometry of Mg4Bi, as well as several metastable stoichiometries (i.e., Mg3Bi, Mg2Bi, and MgBi) are predicted. Meanwhile, the calculated phonon dispersion curves and elastic constants show that the above five Mg–Bi alloys are dynamically and mechanically stable, respectively. Moreover, the calculated mechanical properties indicate that the studied Mg–Bi alloys with various stoichiometries behave ductility. Simultaneously, they exhibit obvious anisotropic characters and the degree of anisotropy follows the order of MgBi > Mg2Bi > Mg3Bi > Mg4Bi > Mg3Bi2. More importantly, the minimum lattice thermal conductivities of MgBi and Mg2Bi are smaller than that of the well-known Mg3Bi2. The adsorption of O atom on the Mg3Bi (001) surface is more sensitive compared with other four Mg–Bi (001) surfaces.

Effect of bismuth doping and SiC nanodispersion on the thermoelectric properties of solution-processed PbTe

Thermoelectric materials are promising as they found numerous applications in electrical power generation and solid-state cooling. In the last decade, Lead Telluride (PbTe) has emerged as a potential thermoelectric candidate for electrical power generation in the medium temperature range. In the present work, we demonstrate nearly 78% enhancement in thermoelectric figure of merit (zT) of nanostructured PbTe compound through doping with bismuth and dispersing 50 nm SiC nanoparticles. Bismuth doping induces n-type conduction and improves the electrical conductivity, while the SiC nanoinclusions modulate the Seebeck coefficient by carrier energy filtering, in addition to suppressing the lattice thermal conductivity. The significant phonon scattering at multi-scale scattering centers resulted in a minimum lattice thermal conductivity (κL) of 0.69 W/m-K in Bi0.02-Pb0.98Te-8% SiC nanocomposite sample. Finally, the reduced lattice thermal conductivity in conjunction with moderate electrical conductivity and high Seebeck coefficient leads to a zTmax value of 0.32 at 590 K in the sample with 6% SiC content. Hence, the partial substitution of the host atom and the presence of a secondary phase can be another promising strategy to enhance the thermoelectric performance.

N-type (Zr,Ti)NiSn half Heusler materials via mechanical alloying: Structure, Sb-doping and thermoelectric properties

Mechanical alloying has been applied, as an advantageous scalable method, to synthesize Ti1-xZrxNiSn half Heusler materials. This is the first time a synthesis of single phase n-type Ti1-xZrxNiSn half Heusler solid solutions is reported by this technique, along with structural studies and thermoelectric properties. The application of mechanical alloying was successful, as all compositions ranging between x = 0.4–0.8 were in general single phase materials. The lattice thermal conductivity of the series was lower compared to the same compositions prepared by arc melting. Ti0.4Zr0.6NiSn exhibited the minimum lattice thermal conductivity of the series and was selected for doping studies with Sb, with the scope to enhance the thermoelectric performance via the power factor modification. Thermoelectric property measurements resulted in a maximum figure of merit of 0.71 at 762K for Ti0.4Zr0.6NiSn doped with 1.5% Sb.

Multiband transport enables thermoelectric enhancements in the SrMg2Bi2 compound

A small energy offset (ΔE < 0.2 eV) between Γ(pxy) and Γ(pz) band orbitals in AB2X2 Zintl compounds enables the realization of band alignment for an increased band degeneracy as well as an enhanced electronic performance. The SrMg2Bi2 Zintl compound has been theoretically illustrated to have a small ΔE, suggesting an approximately inherent convergence of two band orbitals. Therefore, this work is devoted to the revelation of the thermoelectric potential of the SrMg2Bi2 Zintl compound in a broad Hall carrier concentration of 0.3–5 × 1019 cm−3 by Ag-doping at the Sr site. The electrical transport properties can be well predicted by the single parabolic band model with acoustic phonon scattering, which reveals a multi-band transporting behavior in the heavily doped samples due to Fermi level deepening, leading to a significant zT-enhancement. In terms of the model, a peak zT of up to 1.0 is achievable by assuming the amorphous minimum lattice thermal conductivity, which demonstrates this compound as a promising thermoelectric material.

Discovery of high thermoelectric performance of WS2-WSe2 nanoribbons with superlattice and Janus structures

Transition metal dichalcogenide monolayers have shown enormous potential in thermoelectric application in recent years. We now focus on the thermoelectric properties of WS2-WSe2 nanoribbons with superlattice (SL) and Janus (JA) structures using first-principles calculations. The WS2, WSe2, SL, and JA nanoribbons with the ribbon width from 5 to 7 have high structural stabilities. All nanoribbon electronic structures are semiconductors and the ribbon width will modify bandgaps. It can be also observed that WS2, SL, and JA nanoribbons with a ribbon width of 5 have the largest carrier mobilities (up to ~500–1400 cm2 V−1 s−1) and relaxation times (up to ~400–600 fs). We further calculate the electronic transport coefficients and discover that the SL and JA nanoribbons with a ribbon width of 5 exhibit the largest power factors as high as ~80 mW m−1 K−2. Afterwards, the minimum lattice thermal conductivities of SL and JA nanoribbons are 0.53 W m−1 K−1 and 0.61 W m−1 K−1, which are suppressed owing to the declining phonon group velocity and phonon lifetime. The maximum ZT values of SL and JA nanoribbons can reach 5.47 and 4.13. This investigation provides a solid evidence for the application of WS2-WSe2 nanoribbons as promising thermoelectric materials.

Electronic, elastic, and thermal properties, fracture toughness, and damage tolerance of TM5Si3B (TM = V and Nb) MAB phases

The first-principles calculations are employed herein to predict the electronic, elastic, and thermal properties, fracture toughness, and damage tolerance of TM5Si3B (TM = V and Nb) MAB phases. According to formation enthalpy, phonon dispersion and single-crystal elastic constants, V5Si3B and Nb5Si3B are thermodynamically, dynamically, and mechanically stable. Pugh's ratio, Cauchy pressure, hardness, fracture toughness, and elastic anisotropic indexes are calculated, and V5Si3B and Nb5Si3B are brittle, tolerant to damage, and elastic anisotropic. The possible cleavage plane and slip systems are the (0001) plane and < 11¯00 > |{112¯0} and < 112¯0 > |{0001}, respectively, which is determined by the strong TMII-Si, TM-B, and TMI-Si bonds parallel to the (0001) plane. Finally, lattice thermal conductivity, minimum lattice thermal conductivity, and dependence of heat capacity on temperature are predicted.

HPHT synthesis and enhanced thermoelectric transport properties of double-doped Co4Sb11TexSn1-x skutterudites

The high-pressure and high-temperature (HPHT) technique was employed to prepare skutterudite-based polycrystalline materials Co4Sb11TexSn1-x (x = 0.5, 0.6, 0.7). The thermoelectric properties, as well as electrical transport properties near room temperature, were researched systematically. The results indicated that the Sn and Te co-doped specimens yielded an impressive depression in lattice thermal conductivity (κL) based on the point-defect scattering. The κL exhibited a positive Te doping level dependence. Therefore, a minimum lattice thermal conductivity was 1.41 Wm−1K−1 for Co4Sb11Te0.7Sn0.3. Consequently, the thermoelectric dimensionless figure of merit, ZT, was remarkably enhanced from 300 to 725 K. The maximum ZT was 1.13 for Co4Sb11Te0.7Sn0.3 at 711 K, which is better than that of pure Co4Sb12. This value is nearly improved one order of magnitude and rivals the state-of-the-art single-filled n-type skutterudite compounds. Compared to the traditional synthesized method, high pressure and high-temperature techniques can fundamentally reduce the reaction duration from several days to less than an hour and provide a different route for the synthesis of thermoelectric materials.