Citation:
S. Suryajaya, A. Nabok, F. Davis, A. Hassan, S.P.J. Higson, J. Evans-Freeman, Optical and AFM study of electrostatically assembled films of CdS and ZnS colloid nanoparticles, Applied Surface Science, Volume 254, Issue 15, 30 May 2008, Pages 4891-4898
Abstract:
CdS and ZnS semiconducting colloid nanoparticles coated with the organic shell,
containing either SO3− or NH2+ groups, were prepared using the aqueous phase
synthesis. The multilayer films of CdS (or ZnS) were deposited onto glass,
quartz and silicon substrates using the technique of electrostatic self-
assembly. The films produced were characterized with UV–vis spectroscopy,
spectroscopic ellipsometry and atomic force microscopy. A substantial blue shift
of the main absorption band with respect to the bulk materials was found for
both CdS and ZnS films. The Efros equation in the effective mass approximation
(EMA) theoretical model allowed the evaluation of the nanoparticle radius of 1.8
nm, which corresponds well to the ellipsometry results. AFM shows the formation
of larger aggregates of nanoparticles on solid surfa
