title: Enhanced open-circuit voltage in visible quantum dot photovoltaics by engineering of carrier-collecting electrodes.
abstract: Colloidal quantum dots (CQDs) enable multijunction solar cells using a single material programmed using the quantum size effect. Here we report the systematic engineering of 1.6 eV PbS CQD solar cells, optimal as the front cell responsible for visible-wavelength harvesting in tandem photovoltaics. We rationally optimize each of the device's collecting electrodes-the heterointerface with electron-accepting TiO(2) and the deep-work-function hole-collecting MoO(3) for ohmic contact-for maximum efficiency. We report an open-circuit voltage of 0.70 V, the highest observed in a colloidal quantum dot solar cell operating at room temperature. We report an AM1.5 solar power conversion efficiency of 3.5%, the highest observed in >1.5 eV bandgap CQD PV device.
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
authors.forename: Xihua
authors.initials: X
authors.lastname: Wang
authors.forename: Ghada I
authors.initials: GI
authors.lastname: Koleilat
authors.forename: Armin
authors.initials: A
authors.lastname: Fischer
authors.forename: Jiang
authors.initials: J
authors.lastname: Tang
authors.forename: Ratan
authors.initials: R
authors.lastname: Debnath
authors.forename: Larissa
authors.initials: L
authors.lastname: Levina
authors.forename: Edward H
authors.initials: EH
authors.lastname: Sargent