About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Engineering Ceramics: Microstructure-Property-Performance Relations and Applications
|
| Presentation Title |
Thermoelectric Oxide Ceramics Outperforming Single Crystals and with Synergistic Integration of Intergranular Segregation and Intragranular Nano-Inclusions |
| Author(s) |
Cesar-Octavio Romo-De-La-Cruz, Geoffroy Gauneau, Yun Chen, Xueyan Song |
| On-Site Speaker (Planned) |
Cesar-Octavio Romo-De-La-Cruz |
| Abstract Scope |
Thermoelectric technology could be one of the key enablers for decarbonization and energy sustainability. Thermoelectric material's readiness for generating clean energy from waste heat can be accelerated with high-performance oxide, such as Ca3Co4O9-δ. When the thermoelectric conversion efficiency dimensionless figure of merit ZT has a value of 1, it corresponds to 10% efficiency and is acceptable for applications. Single crystal Ca3Co4O9+δ shows outstanding ZT=0.87 at 973K, yet pristine polycrystalline ceramics achieve ZT<0.3. The addition of nanoinclusion in thermoelectric materials is viable for increasing energy conversion efficiencies. Nonetheless, Ca3Co4O9+δ possesses high solubility of various dopants and annihilates Ca3Co4O9+δ lattice integrity and performance. In this work, thermodynamic stable nanoprecipitates were identified and subsequently employed as nanoinclusions in Ca3Co4O9+δBix. The designed oxide ceramics with the synergistic integration of the intragranular substitution, intergranular dopants segregation, and nanoinclusion possess the peaking ZT=1.25 at 1073K, significantly outperforming single crystals over a wide range of temperatures. |