摘要
The freeze-casting method shows great potential for environmentally friendly and industrial scale-up application in thermoelectric materials due to low cost, low toxicity, and pore control. The porous Ca3Co4O9 ceramics with anisotropic thermoelectric performance were fabricated by the freeze-casting method. High porosities, hierarchical pores, and three-dimensional (3D) networks significantly contributed to the suppressed thermal conductivity. An ultralow total thermal conductivity of 0.21 W/(m·K) was obtained. The optimized freeze-casting conditions gave rise to a Seebeck coefficient of 232.3 µV/K. In addition, the ZT value of 0.39 was obtained at 800°C due to the manipulation of hierarchically connected pores and small portions of isolated hexagonal pores. This work provides a new route to form the 3D pores network in oxide thermoelectric ceramics, leading to a decrease in thermal conductivity and optimized thermoelectric performance parallel to the freeze-casting direction.
源语言 | 英语 |
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页(从-至) | 6130-6137 |
页数 | 8 |
期刊 | Journal of the American Ceramic Society |
卷 | 107 |
期 | 9 |
DOI | |
出版状态 | 已出版 - 9月 2024 |