Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Tin-oxide nanoparticles deposited from a beam : what happens to the composition?

Tchaplyguine, M. LU ; Wright, C. ; Shavorskiy, A. LU ; Zhu, S. LU ; Mikkelä, M. H. LU ; Zhang, C. LU ; Björneholm, O. LU ; Mårsell, E. LU ; Mikkelsen, A. LU and Sorensen, S. LU , et al. (2019) In Physical chemistry chemical physics : PCCP 21(11). p.6287-6295
Abstract

The debate around the oxidation states occurring in laboratory-prepared tin-oxide samples has been for a long time an obstacle for an unambiguous assignment of characterization studies performed on such samples. In particular the changes in the Sn core-level energies caused by oxidation - i.e. the chemical shifts - as measured by photoelectron spectroscopy (PES) have been under discussion. The assignment problem is especially pronounced for nanoscale structures, which are important for photovoltaics, electronics, catalysis, and gas sensing. The reasons for the difficulties lie both in the natural properties of tin oxides, which can have substantial deficiencies of oxygen and tin in the lattice, and in the shortcomings of the fabrication... (More)

The debate around the oxidation states occurring in laboratory-prepared tin-oxide samples has been for a long time an obstacle for an unambiguous assignment of characterization studies performed on such samples. In particular the changes in the Sn core-level energies caused by oxidation - i.e. the chemical shifts - as measured by photoelectron spectroscopy (PES) have been under discussion. The assignment problem is especially pronounced for nanoscale structures, which are important for photovoltaics, electronics, catalysis, and gas sensing. The reasons for the difficulties lie both in the natural properties of tin oxides, which can have substantial deficiencies of oxygen and tin in the lattice, and in the shortcomings of the fabrication and PES-characterization procedures themselves. Our recent PES study on tin-oxide nanoparticles fabricated by vapour-aggregation gave a chemical shift two times larger than earlier reported for Sn(iv) oxide for the Sn 4d level. The implemented fabrication technique forms an in-vacuum beam of particles whose composition can be both controlled and characterized by PES. In the present work SnO and SnO2 nanoparticles fabricated this way were deposited from the beam and probed by PES directly, as well as after exposure to air. The deposited nanoparticle films were also imaged by TEM (Transmission Electron Microscopy). The effects of the deposition process and exposure to air on the chemical composition were studied. The PES study of deposited SnO2 nanoparticles in the Sn 4d and Sn 3d core-level regions revealed the same core level shift as for unsupported nanoparticles, indicating that the chemical composition is preserved in the deposition process. The TEM study demonstrated a crystalline structure of separate SnO2 particles with lattice constants close to the macroscopic Sn(iv)-oxide. The PES study on the particles exposed to air showed changes in the composition. For the film of initially SnO particles a higher intermediate oxide was created. For the SnO2 nanoparticle film a lower, but strong, intermediate oxide was observed, likely at the surface.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; ; ; and , et al. (More)
; ; ; ; ; ; ; ; ; ; and (Less)
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Physical chemistry chemical physics : PCCP
volume
21
issue
11
pages
9 pages
publisher
Royal Society of Chemistry
external identifiers
  • scopus:85062884224
  • pmid:30834904
ISSN
1463-9084
DOI
10.1039/c8cp06168h
language
English
LU publication?
yes
id
ff6c3a53-abfc-4b8d-981e-4e17d1fc5784
date added to LUP
2019-03-21 12:04:35
date last changed
2024-03-02 22:46:00
@article{ff6c3a53-abfc-4b8d-981e-4e17d1fc5784,
  abstract     = {{<p>The debate around the oxidation states occurring in laboratory-prepared tin-oxide samples has been for a long time an obstacle for an unambiguous assignment of characterization studies performed on such samples. In particular the changes in the Sn core-level energies caused by oxidation - i.e. the chemical shifts - as measured by photoelectron spectroscopy (PES) have been under discussion. The assignment problem is especially pronounced for nanoscale structures, which are important for photovoltaics, electronics, catalysis, and gas sensing. The reasons for the difficulties lie both in the natural properties of tin oxides, which can have substantial deficiencies of oxygen and tin in the lattice, and in the shortcomings of the fabrication and PES-characterization procedures themselves. Our recent PES study on tin-oxide nanoparticles fabricated by vapour-aggregation gave a chemical shift two times larger than earlier reported for Sn(iv) oxide for the Sn 4d level. The implemented fabrication technique forms an in-vacuum beam of particles whose composition can be both controlled and characterized by PES. In the present work SnO and SnO2 nanoparticles fabricated this way were deposited from the beam and probed by PES directly, as well as after exposure to air. The deposited nanoparticle films were also imaged by TEM (Transmission Electron Microscopy). The effects of the deposition process and exposure to air on the chemical composition were studied. The PES study of deposited SnO2 nanoparticles in the Sn 4d and Sn 3d core-level regions revealed the same core level shift as for unsupported nanoparticles, indicating that the chemical composition is preserved in the deposition process. The TEM study demonstrated a crystalline structure of separate SnO2 particles with lattice constants close to the macroscopic Sn(iv)-oxide. The PES study on the particles exposed to air showed changes in the composition. For the film of initially SnO particles a higher intermediate oxide was created. For the SnO2 nanoparticle film a lower, but strong, intermediate oxide was observed, likely at the surface.</p>}},
  author       = {{Tchaplyguine, M. and Wright, C. and Shavorskiy, A. and Zhu, S. and Mikkelä, M. H. and Zhang, C. and Björneholm, O. and Mårsell, E. and Mikkelsen, A. and Sorensen, S. and Hetherington, C. J.D. and Wallenberg, L. R.}},
  issn         = {{1463-9084}},
  language     = {{eng}},
  number       = {{11}},
  pages        = {{6287--6295}},
  publisher    = {{Royal Society of Chemistry}},
  series       = {{Physical chemistry chemical physics : PCCP}},
  title        = {{Tin-oxide nanoparticles deposited from a beam : what happens to the composition?}},
  url          = {{http://dx.doi.org/10.1039/c8cp06168h}},
  doi          = {{10.1039/c8cp06168h}},
  volume       = {{21}},
  year         = {{2019}},
}