Processing Nanocrystalline Thermoelectric Oxides for High Efficiency Energy Harvesting

这项拨款为开发一种加工技术提供资金，用于制造纳米晶体热电氧化物，以实现高效的能量收集；废热可以被捕获并转化为电能。该工艺将提供一种可行的制造技术，具有经济和可扩展的潜力。热电氧化物材料将被电纺成纳米纤维，然后通过烧结成具有纳米晶体结构的高密度高效体热电氧化物。由此产生的晶粒尺寸预计在几十纳米的范围内，这将大大降低材料的导热性，同时提高热电性能（即转换效率）。对热电纳米纤维和大块纳米晶体氧化物的结构和性能进行详细和系统的表征，以研究热电氧化物的加工-结构-性能关系。热电材料将热量直接转化为电能，有望以环保的方式收集能源循环中损失的大量废热。如果成功，本研究结果将导致热电性能和转换效率提高的热电氧化物材料，并将为废热的高效能量收集奠定基础。本项目开发的制造技术也可以应用于其他纳米晶体材料的加工，具有广泛的应用前景。该项目将培养研究生和本科生。另外，还计划通过“教师研究体验（RET）”、高中生暑期实习、小学科学示范等，向K-12学校开展拓展活动。

This grant provides funding for the development of a processing technique to manufacture nanocrystalline thermoelectric oxides for high efficiency energy harvesting; waste heat can be captured and converted to electricity. This process will provide a viable manufacturing technique that has the potential to be both economical and scalable. Thermo-electric oxide material will be electrospun into nanofibers which will then be consolidated via sintering into high-density high-efficiency bulk thermoelectric oxides with nanocrystalline structure. The resulting grain size is expected to be in the range of tens of nanometers which should substantially reduce the thermal conductivity of the material and at the same time improve the thermoelectric figure-of-merit (i.e conversion efficiency). Detailed and systematic characterization of the resulting structure and properties of thermoelectric nanofibers and bulk nanocrystalline oxides will also be carried out to investigate the processing-structure-property relationship of thermoelectric oxides. Thermoelectric materials that convert heat directly into electricity is promising in harvesting a vast amount of waste heat lost in energy cycle in an environment friendly manner. If successful, the results of this research will lead to thermoelectric oxide materials with improved thermoelectric figure-of-merit and conversion efficiency, and will lay a foundation for high efficiency energy harvesting of waste heat. The manufacturing technique developed in this project can also be applied to process other nanocrystalline materials for a wide range of applications. The project will train graduate and undergraduate students. It will also offer outreach activities to K-12 schools though the Research Experience for Teachers program (RET), summer internship for high school students, and science demos at elementary schools.