Dielectric spectroscopy of silver nanoparticle embedded soda glass

Abstract

Silver-soda glass nanocomposites have been synthesized by using ion exchange technique followed by thermal annealing. Ultraviolet-visible absorption spectroscopy and transmission electron microscopy of the ion exchanged and annealed samples confirmed the presence of silver nanoparticles embedded inside the glass matrix. The size of silver nanoparticles has been found to increase with annealing temperature. The frequency response of the dielectric constant (ε′) and dielectric loss (tan δ) has been studied in both the soda glass and the silver nanoparticle embedded soda glass samples. The dielectric constant increases from 0.9 to 1.89 in the frequency range from 900 kHz to 70 MHz with increasing silver nanoparticle size, which in turn is enhanced as a result of increasing annealing temperature. Possible Coulomb blockade effects have been discussed to explain this novel dielectric behavior.

Synthesis of Silver Polymer Nanocomposites and Their Antibacterial Activity

“…The mean free path of electrons is about 27 nm at room temperature for bulk silver [4]. Amine hydrazine was used as a reducing agent.…”

Effect of heat treatment on optical, dielectric and mechanical properties of silver nanoparticle embedded CaO CaF2P2O5 glass

“…According to coulomb blockade theory, well dispersed silver nanoparticle inside the glass matrix as showed in Fig. 2(a), act as tunneling barriers which inhibit the electrons through the coulomb island leading to increased resistivity of the composite material [29]. This results in enhancing the insulating properties of the glass samples.…”

Sm3+-doped fluorophosphate glass: Formation of Ag nanoparticles via Ag+/K+ ion exchange and their effects on optical and dielectric properties

“…In microscopic view, the Ag NPs will increase the insulating behavior of the glass by preventing charge carriers from moving according to a particular electric field and they can be regarded as several tunneling knots. Coulomb blockade is one of the significant phenomena caused by NPs, which provides awareness regarding to the scheming of inimitable nanocomposites by means of insulating materials [21]. It is perceived from Fig.…”

“…In the case of bulk silver, the mean free path of electrons is about 27 nm at room temperature [21]. The above expression is effective only for the particle size less than the mean free path of electrons [21]. For PAgSm glass, the values for DE 1/2 and the particle size of Ag were obtained as 0.57 eV and 20 nm, respectively.…”

“…The NPs exist in PAgSm glass were developed by migration and aggregation of silver atoms in the glass at the time of Ag + /K + ion exchange process. By assuming the free particle behavior of the conduction electrons, diameter (d) of the silver NPs can be calculated using the expression [21] d…”