Collaborative Research: Exploration of Near-Field Thermophotovoltaic Energy Conversion for Efficient Thermal Energy Recycling

CBET-1236239/1236052 PIs：Park/Cho热光伏（TPV）系统是一种很有前途的能量转换装置，其从红外热辐射产生电力。然而，其低功率吞吐量和低转换效率限制了其在实际应用中的使用。解决这些问题的一种解决方案是利用近场热辐射，其可以超过黑体热辐射几个数量级。然而，由于在保持发射器和接收器之间的平行纳米间隙的困难，近场热辐射的实验研究已被限制到简单的球形或点状发射器的几何形状。因此，该建议的目的是实验研究近场热辐射的平面结构之间的亚微米真空间隙和它的贡献的近场TPV能量转换。本研究的创新点在于：（1）微制造悬浮式热辐射器（加热器），以实现均匀的温度和最小的传导热损失：（2）真空封装的微加热器与膜片，使热辐射作为加热器和膜片之间唯一的热传递机制;以及（3）通过随外部压力改变隔膜曲率来精确控制加热器和隔膜之间的真空间隙。该项目将提供在真空间隙距离为几百纳米的两个平行板之间的近场辐射热传递的定量测量。此外，还将系统地分析近场TPV能量转换装置的优点，并提供近场TPV能量转换装置的功率输出和转换效率的测量方法。这项研究的理论方面将提高我们的热发射电磁波和纳米结构之间的近场相互作用的基本理解，通过表面等离子体共振，散射，衍射和光子本地化。拟议研究的成功将提高对纳米TPV能量转换的科学和技术理解，同时促进教学，培训和学习。PI将付出相当大的努力，让研究生和本科生，特别是那些来自代表性不足的群体，参与尖端的纳米技术研究。他们将获得微/纳米纤维，微/纳米器件的热和电特性以及近场辐射传热测量方面的实践经验。拟议研究的结果将纳入课程，如URI的微/纳米级能源运输，并通过热流体中心（http：//www.example.com）和技术期刊向公众传播。www.thermalfluidscentral.org

CBET-1236239/1236052PIs: Park/Cho A thermophotovoltaic (TPV) system is a promising energy conversion device that generates the electric power from the infrared thermal radiation. However, its low power throughput and poor conversion efficiency restricts the usage in practical applications. One solution for resolving these issues is to utilize near-field thermal radiation, which can exceed the blackbody thermal radiation by several orders of magnitude. However, due to difficulties in maintaining the parallel nanoscale gap between the emitter and the receiver, experimental investigations of near-field thermal radiation have been limited to simple spherical or point-like emitter geometries. This proposal thus aims to experimentally investigate near-field thermal radiation between planar structures within a submicron vacuum gap and its contribution to the near-field TPV energy conversion. The innovative aspects of the proposed research are (1) to microfabricate a suspended thermal emitter (heater) to achieve a uniform temperature and minimize conduction heat loss; (2) to vacuum-package the microheater with a diaphragm to allow thermal radiation as the only heat transfer mechanism between the heater and the diaphragm; and (3) to precisely control the vacuum gap between the heater and the diaphragm by changing the diaphragm curvature with the external pressure. This project will provide the quantitative measurement of the near-field radiative heat transfer between two parallel plates at vacuum gap distances of a few hundred nanometers. In addition, the advantage of near-field TPV energy conversion device will be systematically examined, which also will provide the measurements of the power throughput and conversion efficiency of the near-field TPV device. The theoretical aspect of this research will improve our fundamental understanding of near-field interactions between thermally emitted electromagnetic waves and nanostructures via surface plasmon resonance, scattering, diffraction, and photon localization. The success of the proposed research will enhance scientific and technological understanding of the nanoscale TPV energy conversion while promoting teaching, training, and learning. The PIs will put forth considerable efforts to involve graduate and undergraduate students, especially those from underrepresented group, in cutting-edge nanotechnology research. They will gain hands-on experiences in micro/nanofabrication, thermal and electrical characterization of micro/nanodevices, and near-field radiative heat transfer measurements. The outcome of the proposed research will be incorporated into courses, such as Micro/Nanoscale Energy Transport at URI, and disseminated to the public through Thermal-Fluids Central (http://www.thermalfluidscentral.org) and technical journals.