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Colloidal quantum dot solids for solution-processed solar cells

Abstract

Solution-processed photovoltaic technologies represent a promising way to reduce the cost and increase the efficiency of solar energy harvesting. Among these, colloidal semiconductor quantum dot photovoltaics have the advantage of a spectrally tuneable infrared bandgap, which enables use in multi-junction cells, as well as the benefit of generating and harvesting multiple charge carrier pairs per absorbed photon. Here we review recent progress in colloidal quantum dot photovoltaics, focusing on three fronts. First, we examine strategies to manage the abundant surfaces of quantum dots, strategies that have led to progress in the removal of electronic trap states. Second, we consider new device architectures that have improved device performance to certified efficiencies of 10.6%. Third, we focus on progress in solution-phase chemical processing, such as spray-coating and centrifugal casting, which has led to the demonstration of manufacturing-ready process technologies.

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Figure 1: Advantages of CQD solids.
Figure 2: Advances in purifying the bandgap of CQD solids.
Figure 3: Band edge control via ligands and stoichiometry.
Figure 4: Advanced materials processing techniques for the scalable manufacturing of CQD solids.

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Acknowledgements

This publication is based in part on work supported by Award KUS-11-009-21 made by King Abdullah University of Science and Technology; by the Ontario Research Fund Research Excellence Program; and by the Natural Sciences and Engineering Research Council of Canada.

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Correspondence to Edward H. Sargent.

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Yuan, M., Liu, M. & Sargent, E. Colloidal quantum dot solids for solution-processed solar cells. Nat Energy 1, 16016 (2016). https://doi.org/10.1038/nenergy.2016.16

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