Ultrahigh electrical conductivities and low lattice thermal conductivities of La, Dy, and Nb Co-doped SrTiO3 thermoelectric materials with complex structures
Autor: | Xue Jiang, Huijun Kang, Xiong Yang, Daquan Liu, Xiaoying Zhang, Yanxia Wang, Tongmin Wang |
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Rok vydání: | 2020 |
Předmět: |
Materials science
Polymers and Plastics Mechanical Engineering Doping Metals and Alloys Sintering 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Microstructure Thermoelectric materials 01 natural sciences 0104 chemical sciences chemistry.chemical_compound chemistry Mechanics of Materials Thermoelectric effect Thermal Materials Chemistry Ceramics and Composites Strontium titanate Composite material 0210 nano-technology Ball mill |
Zdroj: | Journal of Materials Science & Technology. 52:172-179 |
ISSN: | 1005-0302 |
Popis: | Microstructural modifications and appropriate element doping are necessary to simultaneously enhance the electrical conductivities and reduce the lattice thermal conductivities of thermoelectric materials. Herein, we propose a strategy of multielement doping combined with a burial sintering process to promote thermoelectric properties. Three-element doped Sr0.9La0.05Dy0.05Ti1−xNbxO3 (x = 0, 0.05, 0.10, 0.15, and 0.20) powders were synthesized by high-energy ball milling, and corresponding bulk samples were prepared by carbon burial sintering. In the bulk samples, we obtained the desired microstructures composed of shell-vesicular architectures with dense dislocations and second phase particles. These materials had ultrahigh electrical conductivities (∼5300 S cm−1 at 300 K), low lattice thermal conductivities (∼1.6 W m−1 K−1 from 700 to 1100 K when x = 0.2) and low total thermal conductivities (minimum value of 2.95 W m−1 K−1 when x = 0.05 at 1100 K). The maximum zT values were 0.28 when x = 0.05 and 0.27 when x = 0.2 at 1100 K. This strategy provides a possible direction for improving the thermoelectric properties of SrTiO3 based materials. |
Databáze: | OpenAIRE |
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