title: Folded-light-path colloidal quantum dot solar cells.
abstract: Colloidal quantum dot photovoltaics combine low-cost solution processing with quantum size-effect tuning to match absorption to the solar spectrum. Rapid advances have led to certified solar power conversion efficiencies of over 7%. Nevertheless, these devices remain held back by a compromise in the choice of quantum dot film thickness, balancing on the one hand the need to maximize photon absorption, mandating a thicker film, and, on the other, the need for efficient carrier extraction, a consideration that limits film thickness. Here we report an architecture that breaks this compromise by folding the path of light propagating in the colloidal quantum dot solid. Using this method, we achieve a substantial increase in short-circuit current, ultimately leading to improved power conversion efficiency.
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
authors.forename: Ghada I
authors.initials: GI
authors.lastname: Koleilat
authors.forename: Illan J
authors.initials: IJ
authors.lastname: Kramer
authors.forename: Chris T O
authors.initials: CT
authors.lastname: Wong
authors.forename: Susanna M
authors.initials: SM
authors.lastname: Thon
authors.forename: André J
authors.initials: AJ
authors.lastname: Labelle
authors.forename: Sjoerd
authors.initials: S
authors.lastname: Hoogland
authors.forename: Edward H
authors.initials: EH
authors.lastname: Sargent