Hydrazine reduces more homogenously without producing
potentially hazardous chemicals. Formation of silver nanoparticles
in the micellar cores was directly seen by a color change of the
solution from colorless to brownish red. Nanoparticle formation
was also confirmed by UV/vis spectra of solutions before and after.
Fig. 2 shows that, for all ratios, the surface plasmon band is seen at
440–449 nm without any absorption shift. The values for all ratios
are summarized in Table 1. It is well known that the absorption
maximum of Ag nanoparticles depends on the particle size. Thus,
the sizes of Ag nanoparticles for all ratios should be almost the
same within the experimental limits, since there is no shift in
absorption maxima obtained from the synthesized silver nanoparticles
for all ratios. On the other hand, the absorbances increase
regularly with increasing Ag:copolymer ratios which is due to
the fact that the nanoparticle concentration is directly related to
precursor ratio. Representative photos showing the color change
after reduction in 5:1 silver:copolymer ratio can be seen in Fig. 2.