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

PI：Guney，DurduProposal编号：1235750机构：密歇根理工大学标题：提高氢化非晶硅光伏器件的太阳能转换效率采用等离子体完美元吸收太阳能光伏(PV)能源转换在技术上是可行的、可持续的解决方案，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)是一种廉价且容易获得的富含地球的太阳能电池材料，它将彻底改变我们生产清洁可持续能源的能力。用a-Si：H制成的光伏电池在所有商业光伏设备中具有最快的能量回收时间，因此对应对气候变化最有用。遗憾的是，a-Si：H的光致电子性能退化限制了它们的整体效率。该项目设想，超材料范例将允许比传统光学增强在理论上更有效地管理来自太阳的光，以便进行光伏转换。例如，太阳光照射到金属表面时，当它与金属中自由电子的集体振荡相互作用时，会沿着金属表面产生波。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？完美的吸波材料？(等离子完美准吸收材料)，以提高太阳能光伏设备的效率。完美的准吸收材料可以设计成具有宽带、偏振无关和广角光学吸收特性。这些关键特征在大多数太阳能电池设计的光学增强方案中缺失，是最大限度地提高太阳能电池效率所必需的。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太阳能电池板对太阳光的时间和空间响应尤为重要。在这个项目中，将优化等离子完美的准吸收材料，以实现最大的太阳能转换效率。利用广角接收，在整个太阳光谱上进行与偏振无关的操作，将获得高的转换效率。这种吸收体将与a-Si：H光伏器件集成在一起，并展示如何将光吸收聚焦到所需的半导体区域，以显著提高整体转换效率。此外，使用这些吸收材料制造超薄太阳能电池是可能的。光学增强将通过减小电池的厚度来直接降低电池中的Staebler-Wronski效应的影响。这将通过两种方式降低a-Si：H光伏的电平成本：1)由于更薄的I层的更高的吞吐量而降低了初始成本；2)由于增强的光捕获而提高了能量转换效率。这项建议中的概念也可以外推到超高效率/高灵敏度的光电探测器/传感器，可以通过太赫兹通过紫外线频率进行调节。此外，该项目将在学术和工业合作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.