الفهرس 
Surface plasmons resonanceOnly 14 pages are availabe for public view
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Abstract
Ag NPs solution was prepared by applying the chemical reduction method from aqueous
solutions of silver nitrate (AgNO3) and sodium borohydride (NaBH4) in appropriate concentrations
in double-distilled water. Au NPs were prepared by Turkevich method. TEM is used to determine
the radius size of the prepared NPs. The overall sizes of prepared Ag NPs and Au NPs are about
14 ±2 nm and 23±2, respectively. The theoretical calculated sizes calculated using Mie’s theory
are almost 16 nm and 23 nm for Ag NPs and Au NPs, respectively.
The absorption and fluorescence spectra for the Cu334 & SRB dyes depend on the dye
concentration and the type of host material. The fluorescence intensity could be tuned by adding
various amounts of M-NPs to the dyes. The distance between the molecule of dye and the surface
M-NP plays an important role to influence the fluorescence intensity of the dye. The space-distance
of dye molecules and NPs control their coupling and overlapping of the plasmon band of NPs and
the absorption band of dye molecules. Consequently, the space distance controls the magnitude of
enhancement/quenching fluorescence of laser dyes.
The photostability of laser dyes was improved by its complexation with M-NPs in the case
of the pumped by the pulsed waves. The photo-degradation of complex dye happened at a fast rate
in the case of the pumped by CW waves. Also, the photo-degradation of dye molecule was faster
in the case of laser dyes dissolved in ILs compared to MeOH.
The photophysical behaviors of organic dyes hybrid with M-NPs in green solvents give a
new methodology and findings may also be of general relevance for the study of the interactions
of organic compounds to surfaces of metallic nanostructured that are essential in the construction
of electro-optical molecular devices. Specifically, the electronic-plasmon coupling occurring at the
excited states might be modulated by external biases, therefore, leading to possible molecular
electronic applications. Through this study, we confirmed the utilizing of green solvents as
alternative to conventional organic solvents in a new applied field, this idea gave a great advantage
of benign solvent for clean industrial technology that focuses on significant environmental
interests. The choice of suitable ILs is critical. Moreover, the selection of NPs that are additive to
laser dye is according to matching between SPR of NPs and the absorption spectrum of laser dye.