Super Large Sn1- xSe Single Crystals with Excellent Thermoelectric Performance.

SnSe single crystals have drawn extensive attention for their ultralow thermal conductivity and outstanding thermoelectric performance. Here, we report super large Sn1- xSe single crystals with excellent thermoelectric properties, fabricated via an advanced horizontal Bridgman technique with great yield and high reproducibility. The obtained single crystals have a super large size of ∼70 × 50 × 15 mm with a considerable weight of 148 g, which leads to a record-high mass density of >6.1 g cm-3. Extensive chemical characterization demonstrates that ∼0.3% Sn vacancies are present, which results in a large concentration of holes, ∼1.2 × 1019 cm-3, and an enhanced power factor of ∼6.1 μW cm-1 K-2 at 793 K. Simultaneously, the Sn-vacancy-induced lattice distortions result in a low thermal conductivity of ∼0.39 W m-1 K-1 at 793 K, leading to a competitive ZT of ∼1.24. This work demonstrates that large-size off-stoichiometric SnSe single crystals hold promise to achieve high thermoelectric performance.

[1]  Qiang Sun,et al.  High Thermoelectric Performance in p‐type Polycrystalline Cd‐doped SnSe Achieved by a Combination of Cation Vacancies and Localized Lattice Engineering , 2019, Advanced Energy Materials.

[2]  J. Zou,et al.  High Thermoelectric Performance in Sintered Octahedron-Shaped Sn(CdIn) xTe1+2 x Microcrystals. , 2018, ACS applied materials & interfaces.

[3]  J. Zou,et al.  Polycrystalline SnSe with Extraordinary Thermoelectric Property via Nanoporous Design. , 2018, ACS nano.

[4]  J. Zou,et al.  Enhancing thermoelectric performance of (Cu1-xAgx)2Se via CuAgSe secondary phase and porous design , 2018, Sustainable Materials and Technologies.

[5]  Yongsheng Zhang,et al.  Realizing High Thermoelectric Performance below Phase Transition Temperature in Polycrystalline SnSe via Lattice Anharmonicity Strengthening and Strain Engineering. , 2018, ACS applied materials & interfaces.

[6]  J. Zou,et al.  High-performance SnSe thermoelectric materials: Progress and future challenge , 2018, Progress in Materials Science.

[7]  J. Zou,et al.  Eco‐Friendly Higher Manganese Silicide Thermoelectric Materials: Progress and Future Challenges , 2018 .

[8]  J. Zou,et al.  Realizing High Thermoelectric Performance in n‐Type Highly Distorted Sb‐Doped SnSe Microplates via Tuning High Electron Concentration and Inducing Intensive Crystal Defects , 2018 .

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

[10]  C. Uher,et al.  Low temperature thermoelectric properties of p-type doped single-crystalline SnSe , 2018 .

[11]  Li-dong Zhao,et al.  Anharmoncity and low thermal conductivity in thermoelectrics , 2018 .

[12]  Jun Jiang,et al.  Charge Transport in Thermoelectric SnSe Single Crystals , 2018 .

[13]  Matthew S. Dargusch,et al.  High Performance Thermoelectric Materials: Progress and Their Applications , 2018 .

[14]  Jingfeng Li,et al.  Achieving High Thermoelectric Figure of Merit in Polycrystalline SnSe via Introducing Sn Vacancies. , 2018, Journal of the American Chemical Society.

[15]  G. J. Snyder,et al.  Significant enhancement of figure-of-merit in carbon-reinforced Cu2Se nanocrystalline solids , 2017 .

[16]  J. Zou,et al.  Eco‐Friendly SnTe Thermoelectric Materials: Progress and Future Challenges , 2017 .

[17]  Jihui Yang,et al.  Solid‐State Explosive Reaction for Nanoporous Bulk Thermoelectric Materials , 2017, Advanced materials.

[18]  Libo Zhang,et al.  The effect of Sm doping on the transport and thermoelectric properties of SnSe , 2017 .

[19]  J. Heremans,et al.  Compromise and Synergy in High‐Efficiency Thermoelectric Materials , 2017, Advanced materials.

[20]  Jun Jiang,et al.  Growth and characterization of large size undoped p-type SnSe single crystal by Horizontal Bridgman method , 2017 .

[21]  Taehoon Kim,et al.  Origin of p-type characteristics in a SnSe single crystal , 2017 .

[22]  Jun Jiang,et al.  Single crystal growth of Sn0.97Ag0.03Se by a novel horizontal Bridgman method and its thermoelectric properties , 2017 .

[23]  J. Vaney,et al.  Reinvestigation of the thermal properties of single-crystalline SnSe , 2017 .

[24]  J. E. Lee,et al.  Achieving ZT=2.2 with Bi-doped n-type SnSe single crystals , 2016, Nature Communications.

[25]  Hui Sun,et al.  The intrinsic thermal conductivity of SnSe , 2016, Nature.

[26]  S. Rhim,et al.  A microscopic study investigating the structure of SnSe surfaces , 2016 .

[27]  Lei Yang,et al.  n-Type Bi2Te3-xSex Nanoplates with Enhanced Thermoelectric Efficiency Driven by Wide-Frequency Phonon Scatterings and Synergistic Carrier Scatterings. , 2016, ACS nano.

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

[29]  Guangbiao Zhang,et al.  Outstanding thermoelectric performances for both p- and n-type SnSe from first-principles study , 2015 .

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

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

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

[33]  M. Dresselhaus,et al.  New Directions for Low‐Dimensional Thermoelectric Materials , 2007 .

[34]  J. Zou,et al.  Achieving high Figure of Merit in p-type polycrystalline Sn0.98Se via self-doping and anisotropy-strengthening , 2018 .