CAREER: Control of Charge Carrier Dynamics in Complex Thermoelectric Semiconductors

这个项目的目标是揭示和控制复杂结构半导体中的电荷传输，最终生产出下一代热电材料。先进热电材料的发展可能会通过太阳能热电发电机、热电联产和余热回收对国家的能源组合产生相当大的影响。更广泛地说，这个项目将使我们深入了解复杂半导体中的电荷传输对其他应用(如透明导体、光伏材料、电力电子)的影响。这些研究工作将通过数据驱动的主动学习模块融入课堂。社区学院的学生将通过这个项目的暑期研究从事固态材料化学和物理。技术摘要在热电材料中，载流子输运的能量依赖性对决定热电势起着关键作用。此外，固态化学和半导体中电荷传输之间的相互作用特别丰富，因为即使是稀释的化学扰动也会对电子性质产生深远的影响。因此，理解和控制依赖于能量的电荷输运是一个巨大的挑战。在这个项目中，目标是将结构确定和第一性原理计算方面的最新进展与单晶生长和先进的输运测量相结合，通过仔细整合这些测量对电荷输运产生深刻的洞察。在固态和材料化学计划的支持下，这一理解将揭示电荷载流子输运的能量依赖性以及相关的结构微扰，这些微扰可以显著改变这些性质。

Non-Technical AbstractThe objective of this project is to reveal and control charge transport in structurally complex semiconductors to ultimately yield the next generation of thermoelectric materials. The development of advanced thermoelectric materials could have a considerable impact on the nation's energy portfolio through solar thermoelectric generators, cogeneration, and waste heat recovery. More broadly, this program will lead to a deep understanding of charge transport in complex semiconductors that impacts other applications (e.g. transparent conductors, photovoltaic materials, power electronics). These research efforts will be integrated into the classroom through data-driven active learning modules. Community college students will be engaged in solid state materials chemistry and physics through summer research on this project. Technical AbstractIn thermoelectric materials, the energy-dependence of charge carrier transport plays a key role in determining the thermopower. Further, the interplay between solid state chemistry and charge transport in semiconductors is particularly rich due to the profound effects that even dilute chemical perturbations exert on electronic properties. There is thus a grand challenge to understand and control the energy dependence charge transport. In this project, the goal is to combine recent advances in structural determination and first principles calculations, in concert with single crystal growth and advanced transport measurements, to yield deep insight into charge transport through the careful integration of these measurements. With the support of the Solid State and Materials Chemistry program, this understanding will reveal the energy-dependence of charge carrier transport and the associated structural perturbations which can dramatically alter these properties.