Sol-gel synthesis and characterization of the Ag2O-SiO2 system

Binary silver silicate (SS) (XAg2O + (1-X) SiO2; X = 0.1-0.9 in steps of 0. 1) system was synthesized through sol-gel route for various compositions co ntaining SiO2 (F = SiO2) and modifier (M = Ag2O) oxides. All the synthesize d SS xerogel compositions were characterized by XRD, FTIR, EDS, WDS, SEM an d impedance spectroscopy techniques. The XRD spectrum showed mixed (amorpho us and crystalline) phases. The formation of the SiO2 network, and presence of SI-OH and NO3 were confirmed by FTIR. Chemical compositions of each ele ment in the SS system were estimated from the EDS and WDS measurements. The SEM micrographs showed that the SS compounds have two phases and the assum ption was further supported by EDS, XRD, and IR results. Electrical conduct ivity of the SS system was estimated from the impedance data and was found to be on the order of 10(-3) cm(-1) Ohm(-1). The role of the observed high ionic conductivity in the SS system is explained using the existing theoret ical models. (C) 2000 Elsevier Science S.A. All rights reserved.