Mapping the origins of luminescence in ZnO nanowires by STEM-CL
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
In semiconductor nanowires, understanding both the sources of luminescence (excitonic recombination, defects, etc.) and the distribution of luminescent centers (be they uniformly distributed, or concentrated at structural defects or at the surface) is important for synthesis and applications. We develop scanning transmission electron microscopy-cathodoluminescence (STEM-CL) measurements, allowing the structure and cathodoluminescence (CL) of single ZnO nanowires to be mapped at high resolution. Using a CL pixel resolution of 10 nm, variations of the CL spectra within such nanowires in the direction perpendicular to the nanowire growth axis are identified for the first time. By comparing the local CL spectra with the bulk photoluminescence spectra, the CL spectral features are assigned to internal and surface defect structures. Hyperspectral CL maps are deconvolved to enable characteristic spectral features to be spatially correlated with structural features within single nanowires. We have used these maps to show that the spatial distribution of these defects correlates well with regions that show an increased rate of nonradiative transitions.
Date Issued
2019-02-07
Date Acceptance
2019-01-06
Citation
Journal of Physical Chemistry Letters, 2019, 10 (3), pp.386-392
ISSN
1948-7185
Publisher
American Chemical Society
Start Page
386
End Page
392
Journal / Book Title
Journal of Physical Chemistry Letters
Volume
10
Issue
3
Copyright Statement
© 2019 American Chemical Society. This is an open access article published under a Creative Commons Attribution (CC-BY - https://creativecommons.org/licenses/by/4.0/) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/30614706
Grant Number
EP/K035274/1
Subjects
03 Chemical Sciences
02 Physical Sciences
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2019-01-07