Colloidal quantum dot photovoltaics: The effect of polydispersity

Handle URI:
http://hdl.handle.net/10754/562089
Title:
Colloidal quantum dot photovoltaics: The effect of polydispersity
Authors:
Zhitomirsky, David; Kramer, Illan J.; Labelle, André J.; Fischer, Armin H.; Debnath, Ratan K.; Pan, Jun; Bakr, Osman M. ( 0000-0002-3428-1002 ) ; Sargent, E. H.
Abstract:
The size-effect tunability of colloidal quantum dots enables facile engineering of the bandgap at the time of nanoparticle synthesis. The dependence of effective bandgap on nanoparticle size also presents a challenge if the size dispersion, hence bandgap variability, is not well-controlled within a given quantum dot solid. The impact of this polydispersity is well-studied in luminescent devices as well as in unipolar electronic transport; however, the requirements on monodispersity have yet to be quantified in photovoltaics. Here we carry out a series of combined experimental and model-based studies aimed at clarifying, and quantifying, the importance of quantum dot monodispersity in photovoltaics. We successfully predict, using a simple model, the dependence of both open-circuit voltage and photoluminescence behavior on the density of small-bandgap (large-diameter) quantum dot inclusions. The model requires inclusion of trap states to explain the experimental data quantitatively. We then explore using this same experimentally tested model the implications of a broadened quantum dot population on device performance. We report that present-day colloidal quantum dot photovoltaic devices with typical inhomogeneous linewidths of 100-150 meV are dominated by surface traps, and it is for this reason that they see marginal benefit from reduction in polydispersity. Upon eliminating surface traps, achieving inhomogeneous broadening of 50 meV or less will lead to device performance that sees very little deleterious impact from polydispersity. © 2012 American Chemical Society.
KAUST Department:
Physical Sciences and Engineering (PSE) Division; Solar and Photovoltaic Engineering Research Center (SPERC); Materials Science and Engineering Program; Functional Nanomaterials Lab (FuNL)
Publisher:
American Chemical Society
Journal:
Nano Letters
Issue Date:
8-Feb-2012
DOI:
10.1021/nl2041589
PubMed ID:
22257205
Type:
Article
ISSN:
15306984
Sponsors:
This publication is based in part on work supported by Award No. KUS-11-009-21 made by King Abdullah University of Science and Technology (KAUST), by the Ontario Research Fund Research Excellence Program, by the Natural Sciences and Engineering Research Council (NSERC) of Canada, and by Angstrom Engineering and Innovative Technology. D.Z., I.J.K., and R.D. acknowledge the financial support through the NSERC CGS D Scholarship, the Ontario Graduate Scholarship and the MITACS Elevate Strategic Fellowship, respectively. The authors would also like to acknowledge the technical assistance and scientific guidance of L. Brzozowski, E. Palmiano, R. Wolowiec, D. Kopilovic, and S. Hoogland.
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Materials Science and Engineering Program; Solar and Photovoltaic Engineering Research Center (SPERC)

Full metadata record

DC FieldValue Language
dc.contributor.authorZhitomirsky, Daviden
dc.contributor.authorKramer, Illan J.en
dc.contributor.authorLabelle, André J.en
dc.contributor.authorFischer, Armin H.en
dc.contributor.authorDebnath, Ratan K.en
dc.contributor.authorPan, Junen
dc.contributor.authorBakr, Osman M.en
dc.contributor.authorSargent, E. H.en
dc.date.accessioned2015-08-03T09:44:32Zen
dc.date.available2015-08-03T09:44:32Zen
dc.date.issued2012-02-08en
dc.identifier.issn15306984en
dc.identifier.pmid22257205en
dc.identifier.doi10.1021/nl2041589en
dc.identifier.urihttp://hdl.handle.net/10754/562089en
dc.description.abstractThe size-effect tunability of colloidal quantum dots enables facile engineering of the bandgap at the time of nanoparticle synthesis. The dependence of effective bandgap on nanoparticle size also presents a challenge if the size dispersion, hence bandgap variability, is not well-controlled within a given quantum dot solid. The impact of this polydispersity is well-studied in luminescent devices as well as in unipolar electronic transport; however, the requirements on monodispersity have yet to be quantified in photovoltaics. Here we carry out a series of combined experimental and model-based studies aimed at clarifying, and quantifying, the importance of quantum dot monodispersity in photovoltaics. We successfully predict, using a simple model, the dependence of both open-circuit voltage and photoluminescence behavior on the density of small-bandgap (large-diameter) quantum dot inclusions. The model requires inclusion of trap states to explain the experimental data quantitatively. We then explore using this same experimentally tested model the implications of a broadened quantum dot population on device performance. We report that present-day colloidal quantum dot photovoltaic devices with typical inhomogeneous linewidths of 100-150 meV are dominated by surface traps, and it is for this reason that they see marginal benefit from reduction in polydispersity. Upon eliminating surface traps, achieving inhomogeneous broadening of 50 meV or less will lead to device performance that sees very little deleterious impact from polydispersity. © 2012 American Chemical Society.en
dc.description.sponsorshipThis publication is based in part on work supported by Award No. KUS-11-009-21 made by King Abdullah University of Science and Technology (KAUST), by the Ontario Research Fund Research Excellence Program, by the Natural Sciences and Engineering Research Council (NSERC) of Canada, and by Angstrom Engineering and Innovative Technology. D.Z., I.J.K., and R.D. acknowledge the financial support through the NSERC CGS D Scholarship, the Ontario Graduate Scholarship and the MITACS Elevate Strategic Fellowship, respectively. The authors would also like to acknowledge the technical assistance and scientific guidance of L. Brzozowski, E. Palmiano, R. Wolowiec, D. Kopilovic, and S. Hoogland.en
dc.publisherAmerican Chemical Societyen
dc.subjectbandgap engineeringen
dc.subjectcolloidal quantum doten
dc.subjectEnergy landscapingen
dc.subjectphotovoltaicsen
dc.subjectpolydispersityen
dc.subjectsolar cellen
dc.titleColloidal quantum dot photovoltaics: The effect of polydispersityen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.contributor.departmentSolar and Photovoltaic Engineering Research Center (SPERC)en
dc.contributor.departmentMaterials Science and Engineering Programen
dc.contributor.departmentFunctional Nanomaterials Lab (FuNL)en
dc.identifier.journalNano Lettersen
dc.contributor.institutionUniv Toronto, Dept Elect & Comp Engn, Toronto, ON M5S 3G4, Canadaen
kaust.authorPan, Junen
kaust.authorBakr, Osman M.en

Related articles on PubMed

All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.