Detection of Pb2+traces in dispersion of Cs4PbBr6 nanocrystals by in situ liquid cell transmission electron microscopy
Dang, Zhiya ; Manna, Liberato and Baranov, Dmitry LU
(2021)
In Nanoscale
13(4).
p.2317-2323
- Abstract
The Cs4PbBr6 nanocrystals are often used as a starting material for the preparation of green-emitting CsPbBr3 perovskite nanocrystals by means of chemical and physical transformations. Herein, we probe the Cs4PbBr6 nanocrystals dispersed in a solvent by liquid cell transmission electron microscopy (LCTEM). The nanocrystal dispersion in toluene is placed between two electron-transparent membranes separated by a gold spacer in a liquid cell and studied in a high angular annular dark-field scanning TEM mode with a fixed electron dose rate. We observe the spontaneous nucleation and growth of round and dendrite-shaped nanoparticles under electron beam illumination in the areas of solution where no Cs4PbBr6 nanocrystals are seen. These... (More)
The Cs4PbBr6 nanocrystals are often used as a starting material for the preparation of green-emitting CsPbBr3 perovskite nanocrystals by means of chemical and physical transformations. Herein, we probe the Cs4PbBr6 nanocrystals dispersed in a solvent by liquid cell transmission electron microscopy (LCTEM). The nanocrystal dispersion in toluene is placed between two electron-transparent membranes separated by a gold spacer in a liquid cell and studied in a high angular annular dark-field scanning TEM mode with a fixed electron dose rate. We observe the spontaneous nucleation and growth of round and dendrite-shaped nanoparticles under electron beam illumination in the areas of solution where no Cs4PbBr6 nanocrystals are seen. These newly-formed nanoparticles show high contrast and contain Pb as the only heavy element, suggesting that they are made from metallic lead and indicating Pb2+-containing species in solution as their precursor. Also, a small amount of Au0 nanoparticles are formed, most likely due to the dissolution of the gold spacer by free Br-containing species in the nanocrystal dispersion and a subsequent reduction of the leached species under the electron beam. The analysis of the UV-Vis absorption spectra of Cs4PbBr6 nanocrystals and the supernatant isolated from the synthesis points to mixed lead(ii) oleate/bromide species as the likely residue, corroborating LCTEM results. The identification of the residual precursors in Cs4PbBr6 nanocrystal samples after the post-synthetic isolation is an important task because the residues may alter the subsequent reactivity of the nanocrystals.
(Less)
- author
- Dang, Zhiya
; Manna, Liberato
and Baranov, Dmitry
LU
- publishing date
- 2021
- type
- Contribution to journal
- publication status
- published
- in
- Nanoscale
- volume
- 13
- issue
- 4
- pages
- 7 pages
- publisher
- Royal Society of Chemistry
- external identifiers
-
- pmid:33459324
- scopus:85100826909
- ISSN
- 2040-3364
- DOI
- 10.1039/d0nr08584g
- language
- English
- LU publication?
- no
- additional info
- Publisher Copyright: © The Royal Society of Chemistry.
- id
- 0ef1533e-106e-4da8-8836-a7669d499ff9
- date added to LUP
- 2023-01-17 11:54:33
- date last changed
- 2024-03-21 08:14:46
@article{0ef1533e-106e-4da8-8836-a7669d499ff9,
abstract = {{<p>The Cs4PbBr6 nanocrystals are often used as a starting material for the preparation of green-emitting CsPbBr3 perovskite nanocrystals by means of chemical and physical transformations. Herein, we probe the Cs4PbBr6 nanocrystals dispersed in a solvent by liquid cell transmission electron microscopy (LCTEM). The nanocrystal dispersion in toluene is placed between two electron-transparent membranes separated by a gold spacer in a liquid cell and studied in a high angular annular dark-field scanning TEM mode with a fixed electron dose rate. We observe the spontaneous nucleation and growth of round and dendrite-shaped nanoparticles under electron beam illumination in the areas of solution where no Cs4PbBr6 nanocrystals are seen. These newly-formed nanoparticles show high contrast and contain Pb as the only heavy element, suggesting that they are made from metallic lead and indicating Pb2+-containing species in solution as their precursor. Also, a small amount of Au0 nanoparticles are formed, most likely due to the dissolution of the gold spacer by free Br-containing species in the nanocrystal dispersion and a subsequent reduction of the leached species under the electron beam. The analysis of the UV-Vis absorption spectra of Cs4PbBr6 nanocrystals and the supernatant isolated from the synthesis points to mixed lead(ii) oleate/bromide species as the likely residue, corroborating LCTEM results. The identification of the residual precursors in Cs4PbBr6 nanocrystal samples after the post-synthetic isolation is an important task because the residues may alter the subsequent reactivity of the nanocrystals.</p>}},
author = {{Dang, Zhiya and Manna, Liberato and Baranov, Dmitry}},
issn = {{2040-3364}},
language = {{eng}},
number = {{4}},
pages = {{2317--2323}},
publisher = {{Royal Society of Chemistry}},
series = {{Nanoscale}},
title = {{Detection of Pb<sup>2+</sup>traces in dispersion of Cs<sub>4</sub>PbBr<sub>6</sub> nanocrystals by <i>in situ</i> liquid cell transmission electron microscopy}},
url = {{http://dx.doi.org/10.1039/d0nr08584g}},
doi = {{10.1039/d0nr08584g}},
volume = {{13}},
year = {{2021}},
}