Y-type cadmium arachidate LB films were exposed to H2S gas for differe
nt durations. UV-VIS absorption spectra reveal an absorption edge at 4
55-460 nm in a 30 min H2S exposed him which does not change appreciabl
y on further exposure, The blue shifted absorption edge is attributed
to the formation of 30 Angstrom CdS nanoparticles. The H2S exposed fil
ms exhibit two types of layered structures, that is, the original bila
yer spacing of 55.2 Angstrom as well as an additional bilayer spacing
of 44 Angstrom. The XRD peak intensities corresponding to the new bila
yer spacing (44 Angstrom) increase up to 6 h of H2S exposure accompani
ed by an increase in bandgap absorption. These results suggest that Cd
S nanoparticles are formed within domains having tilted arachidate mol
ecules distributed throughout the film without completely destroying t
he original layered structure of the LB film. Copyright (C) 1996 Elsev
ier Science Ltd