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Title: Inorganic-ligand exchanging time effect in PbS quantum dot solar cell

Abstract

We investigate time-dependent inorganic ligand exchanging effect and photovoltaic performance of lead sulfide (PbS) nanocrystal films. With optimal processing time, volume shrinkage induced by residual oleic acid of the PbS colloidal quantum dot (CQD) was minimized and a crack-free film was obtained with improved flatness. Furthermore, sufficient surface passivation significantly increased the packing density by replacing from long oleic acid to a short iodide molecule. It thus facilities exciton dissociation via enhanced charge carrier transport in PbS CQD films, resulting in the improved power conversion efficiency from 3.39% to 6.62%. We also found that excess iodine ions on the PbS surface rather hinder high photovoltaic performance of the CQD solar cell.

Authors:
; ; ; ; ;  [1];  [2]
  1. Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ (United Kingdom)
  2. Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA (United Kingdom)
Publication Date:
OSTI Identifier:
22594363
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CHARGE CARRIERS; CRACKS; FILMS; IODIDES; IODINE; IODINE IONS; ION EXCHANGE; LEAD SULFIDES; LIGANDS; MOLECULES; OLEIC ACID; PHOTOVOLTAIC EFFECT; QUANTUM DOTS; SOLAR CELLS; SURFACES; TIME DEPENDENCE

Citation Formats

Kim, Byung-Sung, Hong, John, Hou, Bo, Cho, Yuljae, Sohn, Jung Inn, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk, Cha, SeungNam, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk, and Kim, Jong Min. Inorganic-ligand exchanging time effect in PbS quantum dot solar cell. United States: N. p., 2016. Web. doi:10.1063/1.4960645.
Kim, Byung-Sung, Hong, John, Hou, Bo, Cho, Yuljae, Sohn, Jung Inn, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk, Cha, SeungNam, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk, & Kim, Jong Min. Inorganic-ligand exchanging time effect in PbS quantum dot solar cell. United States. doi:10.1063/1.4960645.
Kim, Byung-Sung, Hong, John, Hou, Bo, Cho, Yuljae, Sohn, Jung Inn, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk, Cha, SeungNam, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk, and Kim, Jong Min. 2016. "Inorganic-ligand exchanging time effect in PbS quantum dot solar cell". United States. doi:10.1063/1.4960645.
@article{osti_22594363,
title = {Inorganic-ligand exchanging time effect in PbS quantum dot solar cell},
author = {Kim, Byung-Sung and Hong, John and Hou, Bo and Cho, Yuljae and Sohn, Jung Inn, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk and Cha, SeungNam, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk and Kim, Jong Min},
abstractNote = {We investigate time-dependent inorganic ligand exchanging effect and photovoltaic performance of lead sulfide (PbS) nanocrystal films. With optimal processing time, volume shrinkage induced by residual oleic acid of the PbS colloidal quantum dot (CQD) was minimized and a crack-free film was obtained with improved flatness. Furthermore, sufficient surface passivation significantly increased the packing density by replacing from long oleic acid to a short iodide molecule. It thus facilities exciton dissociation via enhanced charge carrier transport in PbS CQD films, resulting in the improved power conversion efficiency from 3.39% to 6.62%. We also found that excess iodine ions on the PbS surface rather hinder high photovoltaic performance of the CQD solar cell.},
doi = {10.1063/1.4960645},
journal = {Applied Physics Letters},
number = 6,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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