Dielectric properties of nanophase Ag2HgI4 and Ag2HgI4-Al2O3 nanocomposites

Abstract

The dielectric properties of nanophase Ag2HgI4 and Ag2HgI4-Al2O3 nanocomposites at different frequencies have been studied over a temperature range covering the stability range of β phase of Ag2HgI4 and beyond the β to α phase transition temperature. ε′, tan δ, and σa.c of nanophase Ag2HgI4 and Ag2HgI4-Al2O3 nanocomposites were found to be larger than the reported values for polycrystalline pellets of Ag2HgI4. The dielectric properties of the nanocomposites were found to be a function of the wt.% of nano alumina. The observed changes are attributed to the grain boundary properties of nanophase materials and to the microsize space charge effects.