1. Extremely low thermal conductivity of β−Ga2O3 with porous structure.
- Author
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Wu, H. J., Ning, S. T., Qi, N., Ren, F., Chen, Z. Q., Su, X. L., and Tang, X. F.
- Subjects
THERMAL conductivity ,THERMOELECTRIC conversion ,CHARGE carrier mobility ,THERMAL stability ,THERMOELECTRIC materials ,LOW temperatures - Abstract
Due to the ultrawide bandgap (4.9 eV), high carrier mobility (300 cm 2 V − 1 s − 1 ), and high thermal stability, β − Ga 2 O 3 can be a potential candidate for high-temperature thermoelectric materials. However, the intrinsically high thermal conductivity may hinder its application for thermoelectric conversion. In this work, porous β − Ga 2 O 3 was prepared by the solvothermal method together with spark plasma sintering technology. Positron lifetime measurement and N 2 adsorption confirm the introduction of pores by adding sucrose in the sample preparation. The sucrose-derived β − Ga 2 O 3 sintered at a relatively low temperature of 600 ° C remains highly porous, which results in an extremely low thermal conductivity of 0.45 W m − 1 K − 1 at room temperature, and it further decreases to 0.29 W m − 1 K − 1 at 600 ° C. This is the lowest thermal conductivity for β − Ga 2 O 3 reported so far. Our work provides an avenue to reduce the thermal conductivity for β − Ga 2 O 3 and is believed to be widely applicable to many other thermoelectric materials. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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