Synthesis of ZnO based nanopowders via a non-hydrolytic sol gel technique and their densification behaviour and varistor properties

Abstract

Hexagonal nanocrystalline varistor grade ZnO particles with size 50 nm and the specific surface area of 8 m2/g have been prepared by non-aqueous gelation technique involving diethylene glycol and triethanolamine. The as-prepared varistor nanopowders were analyzed with the support of XRD, TG/DTA, FTIR, TMA, SEM and TEM. Varistor discs were fabricated by pressing and their densification was studied at 850, 950, 1050 and 1150°C. The evolution of varistor microstructures, extent of grain growth and the influence of microstructure on the I-V properties were explored and presented.