CAREER: Investigating Process-Structure-Property Correlations of Nitrides and Oxides for High Temperature Thermoelectric Applications

该学院早期职业发展（CAREER）计划拨款提供资金，用于研究具有多个长度尺度结构的纳米结构体氮化物和氧化物的新加工机制，用于高温热电发电。潜在的假设是，多个长度尺度的纳米结构可以通过工艺工程来控制，因此可以作为一种有效的方法来调整热电性能，通过解耦的电气和热性能。为了验证这一假设，一个综合的实验和理论研究被用来检查处理相关的参数，包括原子尺度，纳米尺度和微米尺度的结构和它们相应的热电性能的影响。氮化镓和氧化锌是这项工作的模型系统，因为它们有前途的热电性能和在高温下的机械和化学稳定性。如果成功，该计划将使一类新的具有成本效益，热稳定和无毒的热电材料在高温下回收浪费的能量。工业过程中产生的废热总量为1500万亿BTU/年，其中温度通常超过1000 K。由于目前技术的工作温度限制在800 K以下，因此一种在1000 K以下仍保持稳定的新型热电材料将为回收这种浪费的能量做出关键贡献。从这个项目中获得的科学可以更广泛地转化为热电，光伏和激光设备的进一步发展。这个职业项目的教育贡献包括在能源相关的课程中创建跨学科教育和研究模块，加强代表性不足的学生对科学和工程的参与，并与K-12学生进行外联，以追求科学和工程职业。

This Faculty Early Career Development (CAREER) Program grant provides funding to investigate new processing mechanisms of nanostructuring bulk nitrides and oxides with multiple length-scale structures for high temperature thermoelectric power generation. The underlying hypothesis is that multiple length-scale nanostructures can be controlled by process engineering and thus be used as an effective method to tune thermoelectric properties by decoupling electrical and thermal properties. To test this hypothesis, an integrated experimental and theoretical study is used to examine the processing-related parameters including atomic-scale, nanoscale, and micro-scale structures and their corresponding effects on thermoelectric properties. Gallium nitride and zinc oxide are the model systems for this work due to their promising thermoelectric properties and mechanical and chemical stability at high temperatures. If successful, this program will enable a new class of cost-effective, thermally stable and nontoxic thermoelectric materials for wasted energy recovery at high temperatures. A total of 1500 trillion BTU/year of waste heat is generated from industrial processes where temperatures typically exceed 1000K. A new class of thermoelectric materials that are robust up to 1000K will make a key contribution to recover this wasted energy since the operational temperature of current technology is limited to below 800K. The science gained from this project can be transformed more broadly into the further development of thermoelectric, photovoltaic, and laser devices. The educational contributions of this CAREER project include creating interdisciplinary education and research modules within energy-related curriculums, enhancing underrepresented students' participation in science and engineering, and outreach to K-12 students to pursue a career in science and engineering.