Electrical engineering

Physics

Seebeck coefficient

Engineering

Ceramic

Composite material

Materials science

Thermoelectric materials

Condensed matter physics

Electrical resistivity and conductivity

Thermal conductivity

Thermoelectric effect

Thermodynamics

Journal of Advanced Ceramics

Oxide-based ceramics could be promising thermoelectric materials because of their thermal and chemical stability at high temperature. However, their mediocre electrical conductivity or high thermal conductivity is still a challenge for the use in commercial devices. Here, we report significantly suppressed thermal conductivity in SrTiO 3 -based thermoelectric ceramics via high-entropy strategy for the first time, and optimized electrical conductivity by defect engineering. In high-entropy (Ca 0.2 Sr 0.2 Ba 0.2 Pb 0.2 La 0.2 )TiO 3 bulks, the minimum thermal conductivity can be 1.17 W/(m·K) at 923 K, which should be ascribed to the large lattice distortion and the huge mass fluctuation effect. The power factor can reach about 295 μW/(m·K 2 ) by inducing oxygen vacancies. Finally, the ZT value of 0.2 can be realized at 873 K in this bulk sample. This approach proposed a new concept of high entropy into thermoelectric oxides, which could be generalized for designing high-performance thermoelectric oxides with low thermal conductivity.

Electrical and thermal transport behaviours of high-entropy perovskite thermoelectric oxides