NSF/DOE Thermoelectrics Partnership: INORGANIC-ORGANIC HYBRID THERMOELECTRICS

NSF/DOE 热电合作伙伴关系：无机-有机混合热电学

• 批准号: 1048702
• 负责人: Sreeram Vaddiraju
• 金额: $ 42.7万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1048702&HistoricalAwards=false
• 关键词: NSF; DOE; Thermoelectrics; Partnership; INORGANIC

1048702VaddirajuIntellectual Merit: The proposal uses solid-state thermoelectric modules to convert automobile waste heat directly into clean electricity without contributing additional greenhouse gas emissions. Suitable thermoelectric devices require: 1) high conversion efficiencies, 2) optimized form factor, 3) high stability, and 4) tunability for optimized system design. For widespread use of thermoelectric modules in automobiles, a zT3 is needed, which is not possible with the current state-of-the-art devices. Recent theoretical predictions indicate that one-dimensional nanostructures (nanowires) are useful for the fabrication of highly efficient thermoelectric modules. Fabrication of thermoelectric devices and modules with zT3 performance requires answering two overarching questions: Q1) what are the sizes and chemical compositions of inorganic nanowires required for achieving zT3 performance? Q2) how can these nanowires be integrated on a large-scale into thermoelectric devices and modules? This proposal?s hypothesis is that thermoelectric devices with zT3 can be fabricated through an ?out-of-the-box? approach that utilizes organic and inorganic materials in unison, performed through homogeneous ?molecular wiring? of inorganic nanowires either to each other or though heterogeneous ?wiring? to organic semiconductor thin films. These two approaches are expected to solve the elusive problem of large-scale integration of nanomaterials while also providing the necessary flexibility for judicious selection of both the chemical components for high thermoelectric performance. The final goal of demonstrating zT3 performance in large ( 1inch2) inorganic-organic hybrid TE devices will be realized by: 1) Using well-known chemical vapor deposition techniques, modified to this application, to synthesize both inorganic nanowires and organic thin films, followed by assembling them using ?molecular wiring? into cells of various sizes ranging from a few nm2 to a few cm2. 2) Systematically studying the effect of inorganic nanowire size and organic conducting polymer thin film chemistry and thickness on their individual thermoelectric performance, and also on their performance when used in unison as ?molecular wired? inorganic-organic hybrids.A second advantage offered by the proposed ?molecular wired? assemblies is enhanced stability against air and moisture-assisted degradation and also against high temperature degradation. This is owed to the saturation of all dangling bonds in the hybrids, leaving no room for both oxygen/moisture adsorption and reaction. This complete saturation of dangling bonds is also expected to make the hybrids stable at very high temperatures. A large temperature difference, as high as 800oC, is available for electricity generation in automobiles. Hence, systematic investigation of the thermoelectric performance of the hybrids over a wide temperature range of 25-800oC will be performed to evaluate the temperature range over which stable zT3 performance could be realized in them.Finally, assembling individual TE devices into modules requires a metal that exhibits low resistance to charge transfer when brought into contact with the TE cells. Hence, the last aspect of the proposed study is to determine the type of the metal required for assembling individual TE devices into TE modules without lowering their performance.Systematic studies of the contact resistance of metal-hybrid junctions will be performed by varying the material of the metal in contact with the hybrids (using transfer length method). The type of the metal required for assembling individual TE devices into modules exhibiting zT3 performance will be deduced.Broader Impact: The educational impact of the proposed work will be the training of high school, undergraduate and graduate students through various avenues. 1) The PI, in collaboration with Mr. Berkan kaya, Assistant Principal at Harmony Science Academy, proposes to train high school students from Harmony Science Academy in Houston, TX and teach them techniques of nanomaterials synthesis and characterization. Small projects aimed at fabrication of energy conversion devices will be designed and the results of their work will be presented at various science fairs and competitions, such as ?International Sustainable World (Engineering, Environment, Energy) (www.isweeep.org). 2) The PI is also a volunteer for the NASA?s Motivating Undergraduates in Science and Technology (http://mustmentor.org) project. Through this avenue, the PI proposes to recruit undergraduate students and train them on the techniques for the fabrication of thermoelectrics and further motivate them to pursue graduate education. 3) Training of graduate students will include development of a new class useful for students across many disciplines. This class tentatively scheduled to be offered in spring 2011 is entitled ?Nanomaterials for Energy Conversion?.

1048702VADDIRAJUINTELLECTUAL FEARIT：该提案使用固态热电模块直接将汽车废物转换为清洁电力，而无需促进其他温室气体排放。合适的热电设备需要：1）高转换效率，2）优化的外形效果，3）高稳定性和4）可调性的可调性，以优化系统设计。为了在汽车中广泛使用热电模块，需要ZT3，而当前最新设备是不可能的。最近的理论预测表明，一维纳米结构（纳米线）对于制造高效的热电模块有用。具有ZT3性能的热电设备和模块的制造需要回答两个总体问题：Q1）实现ZT3性能所需的无机纳米线的尺寸和化学组成是什么？ Q2）如何将这些纳米线集成到热电设备和模块中？ 该建议假设是否可以通过开箱即用的盒子来制造带有ZT3的热电设备？通过均匀的分子布线执行的一致使用有机和无机材料的方法？彼此的无机纳米线或虽然接线？到有机半导体薄膜。预计这两种方法将解决纳米材料大规模整合的难以捉摸的问题，同时还为明智地选择这两种化学成分的高热电性能提供了必要的灵活性。在大型（1inch2）无机杂化型设备中证明ZT3性能的最终目标将通过：1）使用众所周知的化学蒸气沉积技术，对本应用进行了修改，以合成无机的纳米线和有机薄膜，然后使用它们使用？分子连接？进入从几个NM2到几个CM2的各种尺寸的细胞中。 2）系统地研究无机纳米线尺寸和有机导电聚合物薄膜化学和厚度对单个热电性能的影响，以及在Unison中用作分子有线时的性能吗？拟议的“分子有线”提供的无机有机杂种。组件对空气和水分辅助降解以及高温降解的稳定性增强。这是由于杂种中所有悬挂键的饱和度，因此没有留出氧气/水分吸附和反应的空间。悬挂键的完全饱和预计还可以使杂种在非常高的温度下稳定。汽车的发电量高达800oC，高达800oC。因此，将对在25-800oC的较宽温度范围内进行热电性能进行系统研究，以评估可以在其中实现稳定的ZT3性能的温度范围。在这些温度范围内可以在其中实现稳定的ZT3性能。在这些温度范围内，将单个TE设备组装到模块中，需要将单个TE设备组装到模块中，需要在接触Te Cells接触的金属中表现出低电阻传递时的电阻转移。因此，拟议的研究的最后一个方面是确定将单个TE设备组装到TE模块中所需的金属的类型，而无需降低其性能。系统研究金属混合物连接的接触电阻将通过与杂化长度接触（使用传递长度方法）来改变金属的材料。将推导将单个TE设备组装成ZT3性能的模块中所需的金属类型。Broader的影响：拟议工作的教育影响将是对高中，本科生和研究生的培训。 1）PI与Harmony Science Academy的助理校长Berkan Kaya先生合作，建议培训来自德克萨斯州休斯敦和谐科学学院的高中生，并教给他们纳米材料的合成和表征技术。将设计旨在制造能源转换设备的小型项目，其工作结果将在各种科学博览会和竞争中呈现，例如国际可持续世界（工程，环境，能源）（www.isweeep.org）。 2）PI也是NASA的科学技术激励大学（http://mustmentor.org）项目的志愿者。通过这条途径，PI提议招募本科生，并培训他们制造热电学的技术，并进一步激励他们接受研究生教育。 3）对研究生的培训将包括开发一个对许多学科的学生有用的新课程。该课程定于2011年春季提供的纳米材料用于能量转换吗？