Increasing Solar Energy Conversion Efficiency in Hydrogenated Amorphous Silicon Photovoltaic Devices with Plasmonic Perfect Meta-Absorbers

题目：利用等离子体完美元吸收剂提高氢化非晶硅光伏器件的太阳能转换效率太阳能光伏（PV）能量转换是一种技术上可行且可持续的解决方案，可以满足社会的能源需求，但必须进一步降低成本才能广泛采用。氢化非晶硅（a-Si:H）是一种廉价且易于获得的太阳能电池材料，它将彻底改变我们生产清洁可持续能源的能力。用a-Si:H制成的光伏电池在任何商用光伏设备中具有最快的能量回报时间，因此对应对气候变化最有用。不幸的是，光引起的a-Si:H的电子性能退化限制了它们的整体效率。该项目设想，与传统的光学增强技术相比，超材料模式将允许更有效地管理来自太阳的光进行光伏转换。例如，当太阳光与金属中自由电子的集体振荡相互作用时，照射在金属表面上的太阳光会沿着表面产生波。这些表面波被称为表面等离子体激元，可以用来制造等离子体超材料吗？完美的吸收?（等离子体完美元吸收器），以提高太阳能光伏装置的效率。完美的元吸收器可以设计成具有宽带、偏振无关和广角光学吸收特性。这些关键特性，缺乏大多数的光学增强方案的太阳能电池设计，是理想的要求，以最大限度地提高太阳能电池的效率。例如，广角接收对于提高曲面的太阳能转换效率以及最大化电池板对太阳光的时空响应尤为重要。在这个项目中，一个等离子体完美的元吸收器将被优化为最大的太阳能转换效率。高转换效率将来自于在整个太阳光谱上具有广角接收的偏振无关操作。该吸收器将与a-Si:H PV器件集成，并展示如何将光吸收聚焦到所需的半导体区域，以显着提高整体转换效率。此外，利用这些吸收剂制造超薄太阳能电池也将成为可能。光学增强可以减小细胞的厚度，从而直接减小细胞中的斯泰布勒-朗斯基效应。这将通过两种方式降低a-Si:H光伏的平均电力成本：1)由于更薄的i层带来更高的吞吐量而降低初始成本；2)由于增强的光捕获而提高能量转换效率。本提案中的概念也可以外推到超高效率/敏感的光电探测器/传感器，可在太赫兹至紫外线频率范围内调谐。此外，该项目将在学术和工业合作的环境中为两名研究生提供专业和智力培训。

PI: Guney, DurduProposal Number: 1235750Institution: Michigan Technological UniversityTitle: Increasing Solar Energy Conversion Efficiency in Hydrogenated Amorphous Silicon Photovoltaic Devices with Plasmonic Perfect Meta-AbsorbersSolar photovoltaic (PV) energy conversion is a technically viable and sustainable solution to society's energy needs, but the costs must be further reduced for widespread adoption. Hydrogenated amorphous silicon (a-Si:H) is an inexpensive and readily available earth abundant solar cell material, which stands to revolutionize our capability for generating clean sustainable energy. PV cells made with a-Si:H have the fastest energy payback time of any commercial PV device and are therefore the most useful for combating climate change. Unfortunately, the light induced degradation of the electronic properties of a-Si:H limits their overall efficiency. This project envisions that the metamaterial paradigm will allow for managing light from the sun for photovoltaic conversion more efficiently than is theoretically possible with traditional optical enhancement. For example, solar light impinging on a metal surface produces waves along the surface when it interacts with the collective oscillations of free electrons in the metal. These surface waves referred to as surface plasmon polaritons, can be exploited to make plasmonic metamaterial ?perfect absorbers? (plasmonic perfect meta-absorbers) to enhance the efficiency of solar PV devices. Perfectmeta-absorbers can be designed with broadband, polarization-independent, and wide-angle optical absorption features. These critical features, lacking in most optical enhancement schemes for solar cell designs, are ideally required to maximize the efficiency of solar cells. Wide-angle reception, for example, is particularly important to increase solar energy conversion efficiency for curved surfaces, and for maximized temporal and spatial response of the panels to solar light.In this project, a plasmonic perfect meta-absorber will be optimized for maximum solar energy conversion efficiency. High conversion efficiency will be derived from polarization-independentoperation over the entire solar spectrum with a wide-angle reception. This absorber will be integrated with a-Si:H PV device and shown how to focus the optical absorption to the desired semiconducting regions to significantly enhance the overall conversion efficiency. Additionally, it will be possible to make ultra-thin solar cells using these absorbers.The optical enhancement will directly reduce the effects of Staebler-Wronski Effect in the cells by allowing their thicknesses to be decreased. This will result in the reduction in the levelized cost of electricity of a-Si:H PV by two means: 1) reduction in initial cost because of higher throughput from thinner i-layers and 2) improved energy conversion efficiency from enhanced light capturing. The concept in this proposal can be also extrapolated to ultra-high efficient/sensitive photodetectors/sensors tunable over THz through UV frequencies. Additionally, this project will provide professional and intellectual training for two graduate students in an academic and industrial collaborative environment.