Thermoradiative Energy Conversion Devices Based on Narrow Bandgap Antimonide Semiconductors

热辐射（TR）电池中的能量转换将作为废热产生或热源能量收集的新方法进行探索。TR电池可以直接耦合到热源上，并提供了一种具有吸引力的热能转换方式，具有较小的尺寸、重量和复杂性。高性能TR电池的成功将提供一种变革性的能量转换设备技术，为工业过程、空间动力系统和微系统中的热能收集提供简化的废热转换系统。虽然TR电池的能量转换预测是乐观的（功率密度为100 W/m2，电池温度为500K时转换效率为20%），但缺乏实验证明。这项工作旨在弥合理论预测和实验演示之间的差距，通过识别和详细研究现实的TR能量转换材料，设计和实现TR电池器件架构，并通过克服限制功率转换效率的损耗机制的策略来证明TR能量转换概念。以物理为基础的建模和实验材料及装置的研究活动将与与能量转换主题有关的教育和外联活动结合起来。该项目将探索窄带隙半导体材料的基础物理，这将决定实际的TR电池功率转换效率。在目前缺乏实验知识的TR电池工作温度和载流子注入水平下，将详细研究俄歇和肖克利-里德-霍尔复合的基本辐射复合特性和限制非辐射损失机制。这些物理特性将用于优化TR电池器件架构的设计和制造，随后基于InAsSb和InSb的TR电池的后续实验制造和测试，以提供关于功率转换和限制损耗机制的关键反馈。将寻求克服损耗机制的策略，包括抑制ii型多量子阱或超晶格中的俄热复合，pBn等势垒集成架构以减少肖克利-里德-霍尔复合，以及光子设计以最大限度地提高光提取效率。将根据这项工作的研究活动，如TR细胞计算器，开发可供公众使用的在线教育材料。活动将包括参加旨在扩大妇女和代表性不足群体参与科学和工程的地方外联活动。本科生暑期研究项目将在每年的项目中提供给来自以本科生为主的地区机构的学生。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Energy conversion in thermoradiative (TR) cells will be explored as a new approach for wasteheat generation or energy harvesting from thermal sources. TR cells can be directly coupled to the heat source and offer an attractive means for thermal energy conversion with reduced size, weight, and complexity. Success of high-performance TR cells would provide a transformative energy conversion device technology that offers simplified systems for waste heat conversion for industrial processes, space power systems, and thermal energy harvesting in microsystems. While energy conversion projections have been optimistic for TR cells (power density 100 W/m2 and conversion efficiency 20 % for cell temperature of 500K), experimental demonstrations have been lacking. This work aims to bridge the gap between theoretical predictions and experimental demonstrations to prove the TR energy conversion concept through identification and detailed studies of realistic TR energy conversion materials, design and implementation of TR cell device architectures, and through strategies to overcome loss mechanisms that limit power conversion efficiency. Research activities on physics-based modeling and experimental materials and devices will be integrated with educational and outreach activities connected to the theme of energy conversion.This project will explore the underlying physics of narrow bandgap semiconductor materials that will determine practical TR cell power conversion efficiencies. The fundamental radiative recombination properties and limiting non-radiative loss mechanisms of Auger and Shockley-Read-Hall recombination will be studied in detail at TR cell operating temperatures and charge carrier injection levels, where there is currently a lack of experimental knowledge. The physical properties will be used to inform the design and fabrication of optimal TR cell device architectures, followed by subsequent experimental fabrication and testing of TR cells based on InAsSb and InSb to provide critical feedback on power conversion and limiting loss mechanisms. Strategies will be pursued to overcome loss mechanisms, including suppression of Auger recombination in type-II multiquantum wells or superlattices, barrier-integrated architectures such as pBn to reduce Shockley-Read-Hall recombination, and photonic design to maximize optical extraction efficiency. Public access online educational materials will be developed based on the research activities of this work, such as a TR cell calculator. Activities will include participation in local outreach activities aimed at broadening participation from women and underrepresented groups in science and engineering. Undergraduate summer research projects will be offered in each year of the program for students from regional institutions with primarily undergraduate programs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.