Thin-Film Architectures with High Spectral Selectivity for Thermophotovoltaic Cells
Thin-Film Architectures with High Spectral Selectivity for Thermophotovoltaic Cells
复制标题
用于热光伏电池的具有高光谱选择性的薄膜结构
DOI：
10.1021/acsphotonics.8b00508
复制
发表时间：
2018-07-01
期刊：
影响因子：
7
通讯作者：
Lenert, Andrej
中科院分区：
文献类型：
--
作者：
Burger, Tobias;Fan, Dejiu;Lenert, Andrej
热光伏（TPV）系统是一种很有前途的高温热分布式转换技术。为了获得较高的转换效率，必须抑制热发射器和光伏电池之间的亚带隙辐射输运。这可以通过使用频谱选择单元将子带隙辐射回收回发射器来实现。然而，传统的TPV电池具有有限的亚带隙反射率。在这里，我们展示了基于in0.53 ga0.47 as的薄膜结构具有高光谱选择性，包括创纪录的高平均亚带隙反射率（96%）。选择性是通过高质量的材料制成的短光路实现的，材料采用外延提升、高反射率背表面和优化的干涉。此外，我们使用平行板TPV模型来评估特定结构特征对性能的影响，并优化单元结构。我们发现，InGaAs和Au背表面之间的介电间隔层是一个重要的特征，它使预测的TPV效率超过50%（输出功率为2.1 W/cm(2)），显著高于当前的TPV器件。这项工作为高效率、低成本TPV发电机的设计提供了指导。
Thermophotovoltaic (TPV) systems are a promising technology for distributed conversion of high-temperature heat to electricity. To achieve high conversion efficiency, the transport of sub-bandgap radiation between the thermal emitter and PV cell should be suppressed. This can be achieved by recycling sub-bandgap radiation back to the emitter using a spectrally selective cell. However, conventional TPV cells exhibit limited sub-bandgap reflectance. Here we demonstrate thin-film In0.53Ga0.47As-based structures with high spectral selectivity, including record-high average sub-bandgap reflectance (96%). Selectivity is enabled by short optical paths through a high-quality material fabricated using epitaxial lift-off, high-reflectance back surfaces, and optimized interference. In addition, we use a parallel-plate TPV model to evaluate the impact of specific structural features on performance and to optimize the cell architecture. We show that a dielectric spacer between InGaAs and the Au back surface is an important feature that enables a predicted TPV efficiency above 50% (with a power output of 2.1 W/cm(2)), significantly higher than current TPV devices. This work provides guidelines for the design of high-efficiency, low-cost TPV generators.