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

• 作者: Yunpeng ZHENG Mingchu ZOU Wenyu ZHANG Di YI Jinle LAN Ce-Wen NAN Yuan-Hua LIN
• 来源期刊: 先进陶瓷（英文版）
• 年，卷（期）: 2021,（2）
• 所属期刊栏目: Rapid Communication
• 页码范围: 377-384
• 页数: 8页
• 语种: 英文

摘要

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 SrTiO3-based thermoelectric ceramics via high-entropy strategy for the first time, and optimized electrical conductivity by defect engineering. In high-entropy (Ca0.2Sr0.2Ba0.2Pb0.2La0.2)TiO3 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·K2) 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.