A new thermoelectric material Ag8SnS6, with ultra-low thermal conductivity in thin film shape, is prepared on indium tin oxide coated g/ass （ITO） substrates using a chemical process via the electrodeposition techniq...A new thermoelectric material Ag8SnS6, with ultra-low thermal conductivity in thin film shape, is prepared on indium tin oxide coated g/ass （ITO） substrates using a chemical process via the electrodeposition technique. The structural, thermal and electrical properties are studied and presented in detail, which demonstrate that the material is of semiconductor type, orthorhombic structure, with a band gap in the order of 1.56eV and a free carrier concentration of 1.46 × 10^17 cm-3. The thermal conductivity, thermal diffusivity, thermal conduction mode, Seebeck coefficient and electrical conductivity are determined using the photo-thermal deflection technique combined with the Boltzmann transport theory and Cahill＇s model, showing that the AgsSnS6 material has a low thermal conductivity of 3.8 Wm - 1K- 1, high electrical conductivity of 2.4 × 10^5 Sm- 1, Seebeck coefficient of -180μVK-1 and a power factor of 6.9mWK-2m-1, implying that it is more efficient than those obtained in recently experimental investigations for thermoelectric devices.展开更多
The(GeTe)_(x)(AgSbTe_(2))_(100-x)alloys,also called TAGS-x in short,have long been demonstrated as a promising candidate for thermoelectric applications with successful services as the p-type leg in radioisotope therm...The(GeTe)_(x)(AgSbTe_(2))_(100-x)alloys,also called TAGS-x in short,have long been demonstrated as a promising candidate for thermoelectric applications with successful services as the p-type leg in radioisotope thermoelectric generators for space missions.This largely stems from the complex band structure for a superior electronic performance and strong anharmonicity for a low lattice thermal conductivity.Utilization of the proven strategies including carrier concentration optimization,band and defects engineering,an extraordinary thermoelectric figure of merit,zT,has been achieved in TAGS-based alloys.Here,crystal structure,band structure,microstructure,synthesis techniques and thermoelectric transport properties of TAGS-based alloys,as well as successful strategies for manipulating the thermoelectric performance,are surveyed with opportunities for further advancements.These strategies involved are believed to be in principle applicable for advancing many other thermoelectrics.展开更多
The thermoelectric properties of Sr0.61Ba0.39Nb2O6-δ ceramics, reduced in different conditions, are investigated in the temperature range from 323 K to 1073 K. The electrical transport behaviors of the samples are do...The thermoelectric properties of Sr0.61Ba0.39Nb2O6-δ ceramics, reduced in different conditions, are investigated in the temperature range from 323 K to 1073 K. The electrical transport behaviors of the samples are dominated by the thermal-activated polaron hopping in the low temperature range, the Fermi glass behavior in the middle temperature range, and the Anderson localized behavior in the high temperature range. The thermal conductivity presents a plateau at high- temperatures, indicating a glass-like thermal conduction behavior. Both the thermoelectric power factor and the thermal conductivity increase with the increase of the degree of oxygen-reduction. Taking these two factors into account, the oxygen-reduction can still contribute to promoting the thermoelectric figure of merit. The highest ZT value is obtained to be -0.19 at 1073 K in the heaviest oxygen reduced sample.展开更多
The electrical properties and thermoelectric（TE） properties of monolayer In–VA are investigated theoretically by combining first-principles method with Boltzmann transport theory. The ultralow intrinsic thermal con...The electrical properties and thermoelectric（TE） properties of monolayer In–VA are investigated theoretically by combining first-principles method with Boltzmann transport theory. The ultralow intrinsic thermal conductivities of 2.64 W·m^（-1）·K^（-1）（InP）, 1.31 W·m^（-1）·K^（-1）（InAs）, 0.87 W·m^（-1）·K^（-1）（InSb）, and 0.62 W·m^（-1） K^（-1）（InBi） evaluated at room temperature are close to typical thermal conductivity values of good TE materials（κ 〈 2 W·m^（-1）·K^（-1））. The maximal ZT values of 0.779, 0.583, 0.696, 0.727, and 0.373 for InN, InP, InAs, InSb, and InBi at p-type level are calculated at 900 K,which makes In–VA potential TE material working at medium-high temperature.展开更多
基金Supported by the Scientific Research Deanship of University of Dammam under Grant No 2014264
文摘A new thermoelectric material Ag8SnS6, with ultra-low thermal conductivity in thin film shape, is prepared on indium tin oxide coated g/ass （ITO） substrates using a chemical process via the electrodeposition technique. The structural, thermal and electrical properties are studied and presented in detail, which demonstrate that the material is of semiconductor type, orthorhombic structure, with a band gap in the order of 1.56eV and a free carrier concentration of 1.46 × 10^17 cm-3. The thermal conductivity, thermal diffusivity, thermal conduction mode, Seebeck coefficient and electrical conductivity are determined using the photo-thermal deflection technique combined with the Boltzmann transport theory and Cahill＇s model, showing that the AgsSnS6 material has a low thermal conductivity of 3.8 Wm - 1K- 1, high electrical conductivity of 2.4 × 10^5 Sm- 1, Seebeck coefficient of -180μVK-1 and a power factor of 6.9mWK-2m-1, implying that it is more efficient than those obtained in recently experimental investigations for thermoelectric devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.T2125008,92163203,and 52022068)the Innovation Program of Shanghai Municipal Education Commission,the Hefei National Laboratory for Physical Sciences at the Microscale(Grant No.KF2020007)+2 种基金the Shanghai Natural Science Foundation(Grant No.19ZR1459900)Taiyuan University of Science and Technology Scientific Research Initial Funding(No.20222002)the project supported by State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology,No.2022-KF-32)。
文摘The(GeTe)_(x)(AgSbTe_(2))_(100-x)alloys,also called TAGS-x in short,have long been demonstrated as a promising candidate for thermoelectric applications with successful services as the p-type leg in radioisotope thermoelectric generators for space missions.This largely stems from the complex band structure for a superior electronic performance and strong anharmonicity for a low lattice thermal conductivity.Utilization of the proven strategies including carrier concentration optimization,band and defects engineering,an extraordinary thermoelectric figure of merit,zT,has been achieved in TAGS-based alloys.Here,crystal structure,band structure,microstructure,synthesis techniques and thermoelectric transport properties of TAGS-based alloys,as well as successful strategies for manipulating the thermoelectric performance,are surveyed with opportunities for further advancements.These strategies involved are believed to be in principle applicable for advancing many other thermoelectrics.
基金Project supported by the National Basic Research Program of China(Grant No.2013CB632506)the National Natural Science Foundation of China(Grant Nos.51202132 and 51002087)
文摘The thermoelectric properties of Sr0.61Ba0.39Nb2O6-δ ceramics, reduced in different conditions, are investigated in the temperature range from 323 K to 1073 K. The electrical transport behaviors of the samples are dominated by the thermal-activated polaron hopping in the low temperature range, the Fermi glass behavior in the middle temperature range, and the Anderson localized behavior in the high temperature range. The thermal conductivity presents a plateau at high- temperatures, indicating a glass-like thermal conduction behavior. Both the thermoelectric power factor and the thermal conductivity increase with the increase of the degree of oxygen-reduction. Taking these two factors into account, the oxygen-reduction can still contribute to promoting the thermoelectric figure of merit. The highest ZT value is obtained to be -0.19 at 1073 K in the heaviest oxygen reduced sample.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61675032 and 11604019)the National Basic Research Program of China(Grant No.2014CB643900)
文摘The electrical properties and thermoelectric（TE） properties of monolayer In–VA are investigated theoretically by combining first-principles method with Boltzmann transport theory. The ultralow intrinsic thermal conductivities of 2.64 W·m^（-1）·K^（-1）（InP）, 1.31 W·m^（-1）·K^（-1）（InAs）, 0.87 W·m^（-1）·K^（-1）（InSb）, and 0.62 W·m^（-1） K^（-1）（InBi） evaluated at room temperature are close to typical thermal conductivity values of good TE materials（κ 〈 2 W·m^（-1）·K^（-1））. The maximal ZT values of 0.779, 0.583, 0.696, 0.727, and 0.373 for InN, InP, InAs, InSb, and InBi at p-type level are calculated at 900 K,which makes In–VA potential TE material working at medium-high temperature.
