U. Winkler et al., Detailed investigation of CdS nanoparticle surfaces by high-resolution photoelectron spectroscopy, CHEM P LETT, 306(1-2), 1999, pp. 95-102
Direct and detailed information about the surface of differently sized CdS
nanoparticles has been obtained from high-resolution X-ray photoelectron sp
ectroscopy using tunable synchrotron radiation. We identify up to four dist
inct components in the S 2p core level spectra. Two of them are assigned to
bulk and surface S-species of the nanoparticles, the latter arising from a
surface core level shift due to their S-termination. The remaining S 2p co
mponents stem from S-atoms of the stabilizer thiol group bound to Cd and to
S-S-bonds formed by thiol groups which are attached to surface S-atoms. In
the latter case, the oxidation of the nanoparticle surface is drastically
reduced. (C) 1999 Elsevier Science B.V. All rights reserved.