Hot carrier dynamics in perovskite nanocrystal solids: role of the cold carriers, nanoconfinement and the surface
File(s)ColdcarrierspsktNCs_v13.docx (1.27 MB)
Accepted version
Author(s)
Type
Journal Article
Abstract
Carrier cooling is of widespread interest in the field of semiconductor science. It is linked to carrier-carrier and carrier-phonon coupling, and has profound implications for the photovoltaic performance of materials. Recent transient optical studies have shown that a high carrier density in lead-halide perovskites (LHPs) can reduce the cooling rate through a “phonon bottleneck”. However, the role of carrier-carrier interactions, and the material properties that control cooling in LHPs, are still disputed. To address these factors, we utilize ultrafast “pump-push-probe” spectroscopy on LHP nanocrystal (NC) films. We find that the addition of cold carriers to LHP NCs increases the cooling rate, competing with the phonon bottleneck. By comparing different NCs and bulk samples, we deduce that the cooling behavior is intrinsic to the LHP composition, and independent of the NC size or surface. This can be contrasted with other colloidal nanomaterials, where confinement and trapping considerably influence the cooling dynamics.
Date Issued
2020-03-06
Date Acceptance
2020-03-05
Citation
Nano Letters, 2020, 20 (4), pp.2271-2278
ISSN
1530-6984
Publisher
American Chemical Society (ACS)
Start Page
2271
End Page
2278
Journal / Book Title
Nano Letters
Volume
20
Issue
4
Copyright Statement
© 2020 American Chemical Society. This document is the Accepted Manuscript version of a Published Work that appeared in final form in Nano Letters, after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.nanolett.9b04491
Identifier
https://pubs.acs.org/doi/10.1021/acs.nanolett.9b04491
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Multidisciplinary
Chemistry, Physical
Nanoscience & Nanotechnology
Materials Science, Multidisciplinary
Physics, Applied
Physics, Condensed Matter
Chemistry
Science & Technology - Other Topics
Materials Science
Physics
Perovskite nanocrystals
carrier cooling
electron-phonon coupling
ultrafast spectroscopy
LEAD HALIDE PEROVSKITES
PHONON BOTTLENECK
QUANTUM DOTS
RELAXATION DYNAMICS
CHARGE-CARRIERS
HYBRID
SPECTROSCOPY
ENERGY
RECOMBINATION
TRANSITIONS
Perovskite nanocrystals
carrier cooling
electron−phonon coupling
ultrafast spectroscopy
Nanoscience & Nanotechnology
Publication Status
Published
Article Number
acs.nanolett.9b04491
Date Publish Online
2020-03-06