Role of Ag₂S Nanoparticles on the Dynamics of Silver Ions in Silver−Ultraphosphate Glass Nanocomposites

Abstract

Glass nanocomposites in the system xAg 2 S -(1x)(40Ag 2 O -60P 2 O 5 ) have been prepared by mixing the reagent grade Ag 2 S, AgNO 3 , and NH 4 H 2 PO 4 , preheating at 400 °C for 1 h, melting at 900-960 °C, and finally pressing the melts between aluminum plates to form transparent discs of 1 mm thickness. High resolution transmission electron micrographs (HR-TEM) help to find the constitution and composition of the glass nanocomposites. Ag 2 S nanoparticles of typically 10 nm in diameter dispersed in the nanocomposite matrices have been identified. The dynamics of silver ions in these nanocomposites has been studied in a wide frequency range and in a wide temperature range. It has been observed that as x increases from 0.05 to 0.2, the electrical conductivity increases by 1 to 2 orders of magnitude. The activation energy for the electrical conductivity is 0.6-0.5 eV. There is evidence for the involvement of some silver ions in the building up of nanophases. Evaluation of the Ag + -ion concentration from the electrical conductivity using the Nernst-Einstein relation shows that typically 10 21 cm -3 ions participate in the conduction, which is 10-20% of the Ag + -ion concentration, as evaluated from the chemical composition of the material prepared. The ac electrical conductivity data suggest many interesting properties for the nanocomposites from the point of view of its applications. Ag 2 S nanocrystals have also left a signature on the frequency exponent and the crossover frequency. Scaling of the conductivity spectra is observed to be independent of temperature but dependent on Ag 2 S content at high frequencies.

A new silver ion conducting SbI3–Ag4P2O7 nanocomposite solid electrolyte

“…Nanophase solid electrolyte has attracted a great deal of attention in the past decade. The synthesis of ultra fine particles is one of the most important challenges today and such materials exhibit significantly improved characteristics when compared to their coarse grain counterparts (Dutta and Ghosh 2009). A number of FIC materials based on Ag ?…”

Correlation of Structure and Electrical Conductivity of CdI2 Doped Silver Borophosphate Glass and Nanocomposite

“…The importance of ion conducting glasses stems from the interest due to their widespread application in solid state electrolytes. − Different physical and chemical properties of glasses can be tailored by adjusting their compositions. The composition of a glass can be varied in several ways such as by changing the ratio of network modifier to network former, by varying the amount and type of dopant species, etc.…”

Silver Ion Dynamics in Ag2S-Doped Silver Molybdate–Glass Nanocomposites: Correlation of Conductivity and Scaling with Structure

“…Although a lot of studies have been devoted to AgI-doped glasses 24À27 and glass nanocomposites, 23 the study of the ionic conductivity of the Ag 2 S-doped glasses and glass nanocomposite is rare. 28 In this work we focus our attention to study the relaxation dynamics in the Ag 2 S-doped silver molybdateÀglass nanocomposites with an attempt to correlate the ion dynamics to the structure. The relaxation behavior is observed to be highly non-Debye.…”

“…Thus, the microstructure of the glass nanocomposites plays a crucial role in determining the variation of the conductivity and relaxation dynamics with composition. Although a lot of studies have been devoted to AgI-doped glasses − and glass nanocomposites, the study of the ionic conductivity of the Ag 2 S-doped glasses and glass nanocomposite is rare …”