Affordable Access

deepdyve-link
Publisher Website

Photoexcitation of PbS nanosheets leads to highly mobile charge carriers and stable excitons.

Authors
  • Lauth, Jannika1
  • Failla, Michele2
  • Klein, Eugen3
  • Klinke, Christian4
  • Kinge, Sachin5
  • Siebbeles, Laurens D A2
  • 1 Institute of Physical Chemistry and Electrochemistry, Leibniz Universität Hannover, Callinstr. 3A, D-30167 Hannover, Germany. [email protected] and Delft University of Technology, Van der Maasweg 9, NL-2629 HZ Delft, The Netherlands and Cluster of Excellence PhoenixD (Photonics, Optics, and Engineering - Innovation Across Disciplines), Hannover, Germany. , (Germany)
  • 2 Delft University of Technology, Van der Maasweg 9, NL-2629 HZ Delft, The Netherlands. , (Netherlands)
  • 3 Institute of Physical Chemistry, Universität Hamburg, Grindelallee 117, D-20146, Germany. , (Germany)
  • 4 Institute of Physical Chemistry, Universität Hamburg, Grindelallee 117, D-20146, Germany and Chemistry Department, Swansea University, SA2 8PP, UK and Institute of Physics, Universität Rostock, Albert-Einstein-Straße 23, D-18059 Rostock, Germany. , (Germany)
  • 5 Toyota Motor Europe, Materials Research & Development, B-1930 Zaventem, Belgium. , (Belgium)
Type
Published Article
Journal
Nanoscale
Publisher
The Royal Society of Chemistry
Publication Date
Nov 28, 2019
Volume
11
Issue
44
Pages
21569–21576
Identifiers
DOI: 10.1039/c9nr07927k
PMID: 31688863
Source
Medline
Language
English
License
Unknown

Abstract

Solution-processable two-dimensional (2D) semiconductors with chemically tunable thickness and associated tunable band gaps are highly promising materials for ultrathin optoelectronics. Here, the properties of free charge carriers and excitons in 2D PbS nanosheets of different thickness are investigated by means of optical pump-terahertz probe spectroscopy. By analyzing the frequency-dependent THz response, a large quantum yield of excitons is found. The scattering time of free charge carriers increases with nanosheet thickness, which is ascribed to reduced effects of surface defects and ligands in thicker nanosheets. The data discussed provide values for the DC mobility in the range 550-1000 cm2 V-1 s-1 for PbS nanosheets with thicknesses ranging from 4 to 16 nm. Results underpin the suitability of colloidal 2D PbS nanosheets for optoelectronic applications.

Report this publication

Statistics

Seen <100 times