title: The dominant role of exciton quenching in PbS quantum-dot-based photovoltaic devices.
abstract: We present a quantitative measurement of the number of trapped carriers combined with a measurement of exciton quenching to assess limiting mechanisms for current losses in PbS-quantum-dot-based photovoltaic devices. We use photocurrent intensity dependence and short-wave infrared transient photoluminescence and correlate these with device performance. We find that the effective density of trapped carriers ranges from 1 in 10 to 1 in 10,000 quantum dots, depending on ligand treatment, and that nonradiative exciton quenching, as opposed to recombination with trapped carriers, is likely the limiting mechanism in these devices.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Darcy D
authors.initials: DD
authors.lastname: Wanger
authors.forename: Raoul E
authors.initials: RE
authors.lastname: Correa
authors.forename: Eric A
authors.initials: EA
authors.lastname: Dauler
authors.forename: Moungi G
authors.initials: MG
authors.lastname: Bawendi
mesh_terms: D007854:Lead / Q000737:chemistry*; D049449:Luminescence; D036103:Nanotechnology; D009930:Organic Chemicals / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry*; D012666:Semiconductors; D013440:Sulfides / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D009930:Organic Chemicals; D013440:Sulfides; C057718:6-(Dimethylamino)-2-((1E,3E)-4-(4-(dimethylamino)phenyl)-1,3-butadien-1-yl)-1-ethylquinolinium perchlorate; C018391:lead sulfide; D007854:Lead