Nanostructure engineering of infrared-bandgap nanomaterials based solar cells

多结太阳能电池，特别是串联式和三结式太阳能电池，是将太阳能转化为电能的有效途径，因为它们构成的半导体材料具有从可见光到红外(IR)的带隙，并且能够收集太阳能的全光谱。溶液处理的胶体量子点(CQD)是纳米粒子，其直径决定了这些材料吸收太阳的广谱颜色中的哪一种，是多结光伏中光吸收层的候选材料。我们将开发高效率、低成本的串联和跳跃结太阳能电池，以溶液处理的PbS量子点作为红外采集器。在拟议的研究计划中，我们将开发高效的红外带隙CQD太阳能电池。具体地说，我们的目标是通过纳米结构工程在亚微米厚的CQD薄膜中捕获光，从而在红外区域具有80%的外量子效率。我们将通过建模和实验进一步建立物理模型来评估CQD太阳能电池的性能提升，并将我们的纳米结构光伏研究扩展到CQD太阳能电池之外，以实现对再发射光的光管理，以打破Shockley-Queisser限制。所提出的工作为利用红外带隙纳米材料实现高红外光电转换提供了工程解决方案，这将使多结太阳能电池能够实现全太阳光谱采集。与智能电网技术相结合管理电力供应，PBS CQD和可见带隙材料将使低成本、高效率的多结太阳能电池作为能源得到大规模采用，这对加拿大和世界的未来至关重要。

Multi-junction photovoltaics, particularly tandem and triple-junction solar cells, are efficient approaches to convert solar energy into electricity, since their constitute semiconductor materials have bandgaps from visible down to infrared (IR) regions and are capable of collecting full-spectrum of solar energy. Solution-processed colloidal quantum dots (CQDs), nanoparticles whose diameter determines which of the sun's broad spectrum of colours these materials absorb, are candidates for light-absorbing layers in multi-junction photovoltaics. We will develop high-efficiency, low-cost tandem and trip-junction solar cells with solution-processed PbS CQDs as IR harvesters.In the proposed research program, we will develop high-efficiency infrared-bandgap CQD solar cells. Specifically, we are targeting a device having external quantum efficiency of 80% in infrared region by trapping light in sub-micron thick CQD films through nanostructure engineering. We will further develop a physics model to evaluate the performance enhancement in CQD solar cells through modeling and experiment, and extend our research on nanostructured photovoltaics beyond CQD solar cells to achieve light management of reemitted light for breaking the Shockley-Queisser limit.The proposed works provide engineering solutions to achieve high infrared photon-to-electricity conversion by infrared-bandgap nanomaterials, which will enable the multi-junction solar cells for full solar spectrum harvesting. Integrated with smart-grid technology to manage electricity supplies, PbS CQDs and visible-bandgap materials will enable large-scale adoption of low-cost, high-efficiency multi-junction solar cells as energy source, which is critical to Canada and the world's future.