Collaborative Research: NSF/DOE Thermoelectrics Partnership: High Performance Thermoelectric Waste Heat Recovery System Based on Zintl Phase Materials with Embedded Nanoparticles

1048801/1048799 Shakouri/Kauzlaric智能优点：基于大量无毒的锌相硅化镁合金，将开发新型热电材料。提出了一种合成方法，该方法自然地将纳米颗粒嵌入到硅化镁合金基质中，以最小的聚集提供均匀的混合。使用合适浓度和直径的嵌入纳米粒子，中长波声子的散射将降低导热系数。通过控制纳米粒子相对于基质的异质结能带偏移量和势垒，通过热载流子的选择性散射来提高功率因数。初步输运计算表明，在800K时可以实现ZT1.8。将对材料的热电性能进行广泛的表征，结果将与NASA喷气推进实验室和BSST的合作者一起进行标记。广泛的影响：这项提议寻求提供对废热回收有重大影响的基础知识。得益于对合金材料中表面生长的纳米颗粒所实现的电子和声子传输的仔细优化，以及专注于可伸缩块体材料的合成和放电等离子烧结，该计划旨在开发一种低成本、高性能的热电材料。具有化学和工程背景的合作个人之间的密切合作将为从事该项目的研究生提供一个很好的学习机会。学生将在国内和国际会议上展示他们的研究，并将培养对材料开发复杂性的认识。PIs有参与代表性不足的少数族裔外联方案的历史，监督少数族裔学生和受训人员，并参加广泛的活动。

1048801 / 1048799Shakouri / KauzlarichIntellectual Merit: Novel thermoelectric materials will be developed based on abundant and non-toxic Zintl phase magnesium silicide alloys. A synthesis method is proposed that naturally provides embedded nanoparticles within a magnesium silicide alloy matrix, providing uniform mixing with minimal aggregation. With the use of embedded nanoparticles of appropriate concentration and diameter, thermal conductivity will be reduced by scattering of mid-long-wavelength phonons. Controlling the heterostructure band offset and the potential barrier of nanoparticles with respect to the matrix, the power factor will be increased by selective scattering of hot carriers. Preliminary transport calculations show that ZT1.8 at 800K could be achieved. Extensive characterization of the material thermoelectric properties will be performed and the results will be benched marked with collaborators at NASA JPL and BSST.Broader Impact: This proposal seeks to provide fundamental knowledge which can have a major impact on waste heat recovery. Benefiting from the careful optimization of the electron and phonon transport achieved in eptiaxially grown nanoparticle in alloy material and focusing on scalable bulk material synthesis and spark plasma sintering, the plan is to develop a low cost, high performance thermoelectric material. The close collaboration between co-PIs with background in chemistry and engineering will provide a great learning opportunity for graduate students working on the project. Students will present their research at national and international meetings and will develop an appreciation for the complexity of materials development. The PIs have a history of participation in underrepresented minority outreach programs, supervising minority students and trainees, and participating in a broad array of activities.