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THE EFFECT OF ULTRASOUND ON THE SYNTHESIS OF SILVER NANOPARTICLES
MILORAD ANĐELKOVIĆ
Kapetana Radiše Lukića Street, 62. 17530 Surdulica

narrower size distribution from those synthesized without
systems
all
Introduction ultrasound assistance. However, in AgNPs/PMAA)
and
(AgNPs/PVA,
AgNPs/PVP
synthesized with ultrasound assistance agglomeration has
Since the usage of silver nanoparticles (AgNPs) mainly been observed after 60 mintes of sonification.
depends on their properties (their size, shape, interaction
between nanoparticle and stabilizator, surrounding
medium, as well as sythesis route) (Liu et al. 2003) there is
a huge interest on developing methods for controlled
synthesis of nanoparticles.

Figure 3. Colloid UV-Vis spectrum of AgNPs/PVP with
and without ultrasound assistance, as well as the colours of
colloids

Figure 1. Shematic review of synthesis of AgNPs/PMAA It is assumed that during first 60 minutes reduction species
+
from solution additionally reduced Ag , while dispersing
Collective quantized oscilations of conduction electrons separated formed particles and prevent agglomeration.
which absorb light frequency which is the same as their The results also indicated that the smallest nanoparticles
own frequency (Kreibig et al. 1995), that is called - were obtainted from sythetisis routes with equimolar
+
Surface Plasmon Resonance (Figure 2), is the main reason quantity of Ag and monomer unit of a polymer, whereas
of their applications in optics and electronics. in cases of lower concentrations of monomer unit than
+
Ag , results showed that is unable to monitor the effect of
ultrasound on AgNPs size, because of uncontroled
agglomeration, braking and reforming of AgNPs. The
same results were obtained when larger amount of
monomeric units wes used, then destabilization by cross-
linking occured. It is occured when particles “comes closer
to each other“ as a resoult of bonding for same polymer
chain, and can cause agglomeration that way. Higher
viscosity also affected destabilization of those systems, as
a result of unability of Brownian motion
Figure 2. Surface plasmon resonance
Conclusion
Methods of operation
The results showed that AgNPs synthesized with
Silver nanoparticles were synthesized simultaneously by ultrasound assistance had smaller radius and narrower size
chemical reduction (NaBH 4 ) and stabilizations with distribution from those synthesized without ultrasound
polymers (PVA, PVP, PMAA). Synthesis were performed assistance. The results indicated that the larger amount of
both in and out of the ultrasonic bath (operating at 35 Hz monomeric units wes used the larger nanoparticles were
2
and power of 2.5 W/cm ). The position of absorption obtained, probably because of destabilization by cross-
maxima was experimentaly determined by UV-Vis linking, due to unability of Brownian motion in a system
spectrophotometry. The size of nanoparticles was of higher viscosity. In this research the effect of ultrasound
established by interpolation of theoretically obtained on size and size distribution of AgNPs was examined via
dependence of the nanoparticle diameter on the position of spectroscophotometry, therefore in the future, it would be
absorption maxima. For theoretical simulations MiePlot more precise to examine AgNPS size by using
v.3.4 software, which bases calculations on Mie theory, microscopic techniques (TEM, SEM, AFM).
was used.
Literature
Results

[1] Kreibig U., Vollmer M. 1995. Optical properties of
metal clusters. Germany: Springer Berlin Heidelberg
The results showed that AgNPs synthesized with [2] Liu T., Shao H., Li X. 2003. Synthesis of Fe–Al
ultrasound assistance mainly had smaller radius and nanoparticles by hydrogen plasma–metal reaction. Journal
of Physics: Condensed Matter, 15 (17): 2507