Effect of surface capping molecules on the electronic structure of CdSe nanocrystal film

Hyun Ju Choi, Jun Kyu Yang, Hyung-Ho Park

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The optical band gap and the valence band of CdSe nanocrystals were investigated with respect to surface capping molecules by using photoluminescence and synchrotron photoemission spectroscopy. The optical band gap was shown to be mainly dependent on the size of the molecule controlling the inter-particle distance; the valence band, however, mainly depended on the chemical bonding nature of the molecule. UV in air and anneal under ultra high vacuum (UHV) were carried out to control the surface capping pyridine content on CdSe nanocrystal films. With UV treated film, a great reduction in the pyridine content was found, but extra oxygen was absorbed onto the naked CdSe surface. The surface absorbed oxygen exerted a strong influence on the electronic structure of CdSe nanocrystal films. This extra oxygen was successfully removed though UHV-anneal, and it was possible to distinguish the effect of oxygen from the effect of surface capping pyridine on the electronic structure of CdSe nanocrystal film. A quantitative relationship between the valence band maximum of CdSe nanocrystal films and the content of surface-absorbed oxygen could be given.

Original languageEnglish
Pages (from-to)207-210
Number of pages4
JournalThin Solid Films
Volume494
Issue number1-2
DOIs
Publication statusPublished - 2006 Jan 3

Fingerprint

Nanocrystals
Electronic structure
nanocrystals
electronic structure
Molecules
Oxygen
Valence bands
Pyridine
oxygen
molecules
pyridines
Optical band gaps
Ultrahigh vacuum
valence
ultrahigh vacuum
Photoelectron spectroscopy
Synchrotrons
Photoluminescence
synchrotrons
photoelectric emission

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Materials Chemistry

Cite this

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Effect of surface capping molecules on the electronic structure of CdSe nanocrystal film. / Choi, Hyun Ju; Yang, Jun Kyu; Park, Hyung-Ho.

In: Thin Solid Films, Vol. 494, No. 1-2, 03.01.2006, p. 207-210.

Research output: Contribution to journalArticle

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