Surface chemistry of arenethiolate-capped PbS quantum dots and application as colloidally stable photovoltaic ink

Abstract

Suitable post-synthesis surface modification of lead-chalcogenide quantum dots (QDs) is crucial to enable their integration in photovoltaic devices. We have developed a solution-phase ligand exchange strategy that exploits arenethiolate anions to replace the pristine oleate ligands on PbS QDs, while preserving the long-term colloidal stability of QDs and allowing their solution-based processability into photoconductive thin-films. Complete QD surface modification is demonstrated by IR spectroscopy analysis, whereas UV-Vis-NIR Absorption Spectroscopy provides quantitative evaluation of stoichiometry and thermodynamic stability of the resulting system. Arenethiolate ligands permit to reduce the inter-particle distance in PbS QD solids, leading to a drastic improvement of the photoinduced charge transport properties. Therefore, smooth dense-packed thin-films of arenethiolate-capped PbS QDs obtained via a single solution-processing step are integrated in heterojunction solar cells: such devices generate remarkable photocurrent densities (14 mA cm(-2)) and overall efficiencies (1.85%), which are outstanding for a single PbS QD layer. Solution-phase surface modification of QDs thus represents an effective intermediate step towards low-cost processing for all-inorganic and hybrid organic/inorganic QD-based photovoltaics. (c) 2013 Elsevier B.V. All rights reserved.


Tutti gli autori

  • C. Giansante , L. Carbone , C. Giannini , D. Altamura , Z. Ameer , G. Maruccio , A. Loiudice , M. R. Belviso , P. D. Cozzoli , A. Rizzo , G. Gigli

Titolo volume/Rivista

THIN SOLID FILMS


Anno di pubblicazione

2014

ISSN

0040-6090

ISBN

Non Disponibile


Numero di citazioni Wos

7

Ultimo Aggiornamento Citazioni

28/04/2018


Numero di citazioni Scopus

6

Ultimo Aggiornamento Citazioni

28/04/2018


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile