Characterization of TiO ₂ ‐Based Sensor Materials Using Immittafice Spectroscopy

Abstract

The ac electrical data, monitored in the frequency range 5 Hz f 13 MHz, are used to establish the microstructure–property response of titania‐based composite polycrystalline sensor materials. These electrical data, when analyzed utilizing the lumped parameter/complex plane analysis, reveal several contributions from simultaneously operating mechanisms to the terminal admittance of the grain boundary. The nature of the electrically conducting paths, consisting of the lumped series–parallel network in the microstructure, is suggested via an equivalent circuit representation incorporating the underlying mechanisms in a systematic manner.