Two kinds of nanocomposite ultrathin
films, i.e., (Ag@keratin/PDDA)n and (keratin/PDDA) n+Ag(0)
nanoparticles (NP), have been fabricated by layer-by-layer (LbL) deposition and
in situ deoxidization method, respectively. The assembling process was monitored by means of UV-Vis
spectroscopy. Scanning electron microscope (SEM) was used to observe the surface
morphology and thickness of the multilayer films. The distribution of silver NP
within the two LbL films were evaluated by transmission electron microscope
(TEM) measurement. It was found that (Ag@keratin/PDDA)n films present
superior fluorescent properties that that of (keratin/PDDA) n+Ag(0)
NP. TEM results suggest that the fusion of the small silver clusters (which is fluorescent)
is hindered in the direct LbL assembly, while larger Ag NP are formed by the in
situ preparation. The corrosion-resistance
of the Ag@keratin/PDDA multilayer films
against the acid and basic etching solution is also tested.