title: Singlet exciton fission-sensitized infrared quantum dot solar cells.
abstract: We demonstrate an organic/inorganic hybrid photovoltaic device architecture that uses singlet exciton fission to permit the collection of two electrons per absorbed high-energy photon while simultaneously harvesting low-energy photons. In this solar cell, infrared photons are absorbed using lead sulfide (PbS) nanocrystals. Visible photons are absorbed in pentacene to create singlet excitons, which undergo rapid exciton fission to produce pairs of triplets. Crucially, we identify that these triplet excitons can be ionized at an organic/inorganic heterointerface. We report internal quantum efficiencies exceeding 50% and power conversion efficiencies approaching 1%. These findings suggest an alternative route to circumvent the Shockley-Queisser limit on the power conversion efficiency of single-junction solar cells.
authors.affiliation: Cavendish Laboratory, J.J. Thomson Avenue, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: Bruno
authors.initials: B
authors.lastname: Ehrler
authors.forename: Mark W B
authors.initials: MW
authors.lastname: Wilson
authors.forename: Akshay
authors.initials: A
authors.lastname: Rao
authors.forename: Richard H
authors.initials: RH
authors.lastname: Friend
authors.forename: Neil C
authors.initials: NC
authors.lastname: Greenham
mesh_terms: D011211:Electric Power Supplies; D007854:Lead / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology; D010777:Photochemistry; D017785:Photons; D045663:Quantum Dots; D012993:Solar Energy; D013440:Sulfides / Q000737:chemistry
chemical_list: D013440:Sulfides; C018391:lead sulfide; D007854:Lead